United States 

Environmental Protection AgencyOffi ce of Research  and DevelopmentFort Meade, MD 20755-5350Offi cial BusinessPenalty for Private Use$300EPA/903/B-05/001June 2005

PRESORTED STANDARD

POSTAGE & FEES PAID

EPA

PERMIT No. G-35

Please make all necessary changes on the below label,detach or copy, and return to the address in the upper left-hand corner.If you do not wish to receive these reports, CHECK HERE ;detach, or copy this cover, and return to the address in the upper left-hand corner.

EPA/903/B-05/001 An Introduction to Mid-Atlantic Seasonal Pools
PA

WV

VA

MD

DEDC

NJ

MID-ATLANTIC STATES
EPA/903/B-05/001

June 2005

An Introduction to 

Mid-Atlantic Seasonal Pools

Prepared for:

U.S. Environmental Protection Agency

Mid-Atlantic Integrated Assessment

701 Mapes Road

Fort Meade, MD 20755-5350

by:

Lesley J. Brown1

Robin E. Jung 2

1 Perot Systems Government Services

701 Mapes Road

Fort Meade, MD 20755-5350

2 USGS Patuxent Wildlife Research Center

12100 Beech Forest Road

Laurel, MD 20708-4038

Printed on chlorine free 100% recycled paper with 

100% post-consumer fiber using vegetable-based ink.
ii An Introduction to Mid-Atlantic Seasonal Pools

NOTICE

The U. S. Environmental Protection Agency (U.S. EPA) Offi ce of Research and Development 

(ORD), National Health and Environmental Effects Research Laboratory (NHEERL) and the 

U. S. Geological Survey (USGS) Patuxent Wildlife Research Center, Amphibian Research and 

Monitoring Initiative jointly funded the preparation of this manual through Student Services 

Contract, Purchase Order Number 4D-5647-TTTX. Technical editing and graphics support 

were funded by the U.S. EPA ORD, NHEERL through Interagency Agreement DW13939208-

01 with the U. S. Department of Commerce. U.S. EPA Region 3, Environmental Assessment 

and Innovation Division, Environmental Programs Branch provided funding for printing. The 

report was subjected to U.S. EPA’s peer and administrative reviews and has received approval 

for publication as an U.S. EPA document. This product has also cleared the USGS policy 

review. Mention of trade names or commercial products does not constitute endorsement or 

recommendation for use. The recommendations expressed in the manual are solely those of 

the authors and do not necessarily refl ect those of the sponsoring agencies.

The appropriate citation for this report is: 

Brown, L.J. and R.E. Jung. 2005. An Introduction to Mid-Atlantic Seasonal Pools, EPA/903/B05/001. U.S. Environmental Protection Agency, Mid-Atlantic Integrated Assessment, Ft. 

Meade, Maryland.

ABSTRACT

Seasonal pools, also known as vernal ponds, provide important ecological services to the 

mid-Atlantic region. This publication serves as an introduction to seasonal pool ecology 

and management; it also provides tools for exploring seasonal pools, including a full-color 

fi eld guide to wildlife. Seasonal pools are defi ned as having four distinctive features: surface 

water isolation, periodic drying, small size and shallow depth, and support of a characteristic 

biological community. Seasonal pools experience regular drying that excludes populations 

of predatory fi sh. Thus, pools in the mid-Atlantic region provide critical breeding habitat for 

amphibian and invertebrate species (e.g., spotted salamander (Ambystoma maculatum), wood 

frog (Rana sylvatica), and fairy shrimp (Order Anostraca)) that would be at increased risk of 

predation in more permanent waters. 

The distinctive features of seasonal pools also make them vulnerable to human disturbance. 

In the mid-Atlantic region, land-use changes pose the greatest challenges to seasonal pool 

conservation. Seasonal pools are threatened by direct loss (e.g., fi lling or draining of the pool) 

as well as by destruction and fragmentation of adjoining terrestrial habitat. Many of the species 

that depend on seasonal pools for breeding spend the majority of their lives in the surrounding 

lands that extend a radius of 1000 feet or more from the pools; these vital habitats are being 

transected by roads and converted to other land uses. Other threats to seasonal pools include 

biological introductions and removals, mosquito control practices, amphibian diseases, 

atmospheric deposition, and climate change. The authors recommend a three-pronged strategy 

for seasonal pool conservation and management in the mid-Atlantic region: education and 

research, inventory and monitoring of seasonal pools, and landscape-level planning and 

management. 

Key Words: seasonal pools; vernal ponds; wetlands; amphibian conservation; Mid-Atlantic; 

aquatic ecology
iii

ACKNOWLEDGEMENTS

The authors would like to thank Tina Schneider of Maryland-National Capital Park and 

Planning Commission, Patricia Bradley of U.S. Environmental Protection Agency (U.S. EPA) 

Offi ce of Research and Development (ORD), Eric Walbeck of Perot Systems Government 

Services (PSGS), Ronald Landy of U.S. EPA Region 3 and ORD, Wayne Davis of U.S. EPA 

Offi ce of Environmental Information, and Marshall Howe of U.S Geological Survey (USGS) 

Patuxent Wildlife Research Center (PWRC) for general support throughout the process, from 

the initial planning stages to publication.

Thorough reviews of Section 3 and Field Guide to Seasonal Pool Fauna were provided by 

Joseph C. Mitchell of the University of Richmond, Steven M. Roble of Virginia Department 

of Conservation and Recreation, Dave Golden of New Jersey Division of Fish and Wildlife, 

Thomas K. Pauley of Marshall University, Alvin Braswell of North Carolina State Museum of 

Natural Sciences Research Laboratory, and Butch Norden of Maryland Department of Natural 

Resources. Additional comments on Section 3 were provided by Robert T. Brooks of the U.S. 

Department of Agriculture Forest Service, Mick McLaughlin of Clemmys Environmental 

Services, and Jennifer Wykle of West Virginia Department of Natural Resources.

Many people were consulted; the authors particularly drew from the knowledge of Joseph 

Mitchell, Butch Norden, Michael Hayslett of Holiday Lake 4-H Educational Center, Amy 

Jacobs of Delaware Department of Natural Resources and Environmental Control, and Robert 

Cook of Cape Cod National Seashore, National Park Service.

Comments on the manual were generously provided by Evan Grant, Priya Nanjappa, Rebecca 

Chalmers, and Sandra Mattfeldt of USGS PWRC, Denise Clearwater of Maryland Department 

of the Environment, Tina Schneider, Patricia Bradley, Stafford Madison of U.S. EPA Region 1, 

and Naomi Detenbeck of the U.S. EPA Mid-Continent Ecology Division.

Special thanks go to the peer reviewers, who donated a great deal of personal time to improve 

the accuracy and usefulness of the manual: Brian McDonald of West Virginia Natural 

Heritage, Charles Bier of Western Pennsylvania Conservancy, William Sipple, retired U.S. EPA, 

of W.S. Sipple Wetland & Environmental Training & Consulting, and Aram Calhoun of the 

University of Maine. 

Juanita Soto-Smith of PSGS greatly assisted with desktop publishing and graphic design; Priya 

Nanjappa kindly prepared the amphibian species distribution maps for Field Guides 1 and 2; 

Kinard Boone of USGS PWRC assisted with several graphics. 

Many photographers contributed to this publication; their names are noted on the 

photographs. The authors especially thank Steven Roble, Solon Morse of Roger Tory Peterson 

Institute (RTPI), Leo Kenney of the Vernal Pool Association, Bryan S. Windmiller of Hyla 

Ecological Services, Alvin Braswell, John Bunnell of the Pinelands Commission, Tim Maret of 

Shippensburg University and the USGS PWRC Amphibian Research and Monitoring Initiative 

for their multiple donations. 

Any mistakes in interpretation or otherwise are the sole responsibility of the authors.

Acknowledgements
iv An Introduction to Mid-Atlantic Seasonal Pools

CONTENTS

Notice ....................................................................................................................... i

Abstract ................................................................................................................... ii

Acknowledgements ...............................................................................................iii

Section 1: Introduction to Seasonal Pools ........................................................... 1

 1.1: Introduction .................................................................................................................1

 1.2: Purpose and Scope ......................................................................................................2

 1.3: Defi nition of “Seasonal Pool” ......................................................................................3

Section 2: The Greater Seasonal Pool Ecosystem ............................................... 7

 2.1: Setting and Vegetation of Seasonal Pools ...................................................................7

 2.2: Life Zones of Seasonal Pools ..................................................................................... 10

 2.3: Life Histories of Seasonal Pool-Dependent Organisms .......................................... 14

Section 3: Introduction to Seasonal Pool Fauna ................................................17

 3.1: Introduction to Seasonal Pool Fauna ....................................................................... 17

 3.2: Indicator and Facultative Species ............................................................................. 17

 3.3: Salamanders in Seasonal Pools ................................................................................. 21

 3.4: Frogs and Toads in Seasonal Pools ...........................................................................23

 3.5: Reptiles, Birds, and Mammals in Seasonal Pools ....................................................24

 3.6: Invertebrates in Seasonal Pools ................................................................................26

Section 4: Conservation Challenges Facing Seasonal Pools .............................27

 4.1: Direct Loss of Seasonal Pools ....................................................................................27

 4.2: Terrestrial Habitat Loss and Fragmentation ............................................................27

 4.3: Other Conservation Challenges ............................................................................... 31

Section 5: Future Directions: Conservation 

of Seasonal Pools in the Mid-Atlantic Region ....................................................33

 5.1: Seasonal Pool Conservation in the Mid-Atlantic Region ........................................ 33

 5.2: Education and Research on Seasonal Pools .............................................................34

 5.3: Inventory of Seasonal Pools ......................................................................................34

 5.4: Landscape-Level Planning and Management ..........................................................35

Field Guide to Seasonal Pool Fauna .....................................................................37

Appendices ............................................................................................................69

 Appendix A: Techniques to Locate Seasonal Pools ........................................................69

 Appendix B: Techniques to Monitor Seasonal Pools ......................................................73

 Appendix C: Programs to Locate, Map, Monitor, and/or Protect

 Seasonal Pools in the Mid-Atlantic Region ..............................................77

 Appendix D: Sources of Additional Information on Seasonal Pools ............................ 81

Glossary ..................................................................................................................83

Literature Cited..................................................................................................... 85
v

Plate 1-1. Mid-Atlantic seasonal pool ......................................................................................... 1

Plate 1-2. Spotted salamander (Ambystoma maculatum) ........................................................ 1

Plate 1-3. A seasonal pool’s wet stage and dry stage ................................................................. 4 

Plate 1-4. Seasonal pools drying before metamorphosis ........................................................ 6

Plate 2-1. Seasonal forest pool ..................................................................................................... 7

Plate 2-2. Seasonal open-canopy pool ........................................................................................ 8

Plate 2-3. Seasonal scrub-shrub pool ......................................................................................... 8

Plate 2-4. Seasonal forested wetland pool ................................................................................. 9

Plate 2-5. Amplexus between a male and female 

 wood frog (Rana sylvatica) ......................................................................................... 11

Plate 2-6. Release of spotted salamander eggs ........................................................................ 11

Plate 2-7. Recognizing dry seasonal pools ............................................................................... 12

Plate 2-8. Spotted salamanders at pool edge ........................................................................... 12

Plate 3-1. Spermatophores of spotted salamanders ................................................................. 21

Plate 3-2. Egg mass, larva, and adult salamander .................................................................... 22

Plate 3-3. Egg masses, tadpoles, and adult frog ........................................................................ 23 

Plate 3-4. Turtles of seasonal pools ............................................................................................ 24

Plate 3-5. Deer in an open-canopy seasonal pool .................................................................... 25

Plate 3-6. Fairy shrimp in seasonal pools ................................................................................. 26

Plate 4-1. Aerial view of landscape fragmentation .................................................................. 27

Plate 4-2. Terrestrial habitat fragmentation ............................................................................. 28

Plate 4-3. Spotted salamander roadkill ..................................................................................... 29

Plate 4-4. Garbage fi lls this seasonal pool .................................................................................30

PLATES

Plates
vi An Introduction to Mid-Atlantic Seasonal Pools

FIGURES

Figure 1-1. 

Hydrograph of a seasonal pool ............................................................................................................. 4

Figure 2-1.

 Seasonal pool aerial view delineating three life zones .................................................................... 10

Figure 3-1.

Distribution of amphibian indicator species in mid-Atlantic seasonal pools ............................ 19

Figure 3-2.

Breeding phenologies of seasonal pool indicator species ............................................................... 20

BOXES

Box 1-1

Ecological services provided by seasonal pools ................................................................................. 1

Box 1-2

Defi nition of a seasonal pool ................................................................................................................ 3

Box 1-3 

Types of seasonal pools based on hydroperiod .................................................................................. 5

Box 2-1 

Example of regional seasonal pools: Delmarva bays ....................................................................... 9

Box 2-2

Recognizing dry seasonal pools ......................................................................................................... 12

Box 2-3 

Life history of pool-breeding amphibians ........................................................................................ 14

Box 3-1 

Indicator vs. facultative species in seasonal pools ........................................................................... 18

Box B-1

Practices for safely handling and reducing disturbance to amphibians ...................................... 74
1

Section 1: Introduction to Seasonal Pools 1

INTRODUCTION TO SEASONAL POOLS

1.1: Introduction 

Seasonal pools are dynamic habitats that have cycles 

of standing water (Plate 1-1). These unique pools 

fi ll with rainwater, surface runoff, snowmelt, or 

groundwater in the fall, winter, or spring and may 

completely dry out by the summer. Seasonal pools 

are referred to by a variety of names, including 

vernal pools, spring pools, ephemeral wetlands, 

autumnal pools, woodland ponds, and temporary 

ponds. Seasonal pools provide important ecological 

services to the mid-Atlantic region (Box 1-1). 

breeding are rare, threatened, or endangered in parts 

of their mid-Atlantic range, such as the eastern tiger 

salamander (Ambystoma tigrinum tigrinum) that is 

state-listed as endangered in Delaware, New Jersey, 

and Virginia. In the mid-Atlantic region, 26% of all 

state-listed threatened and endangered amphibians 

are dependent on seasonal pools.

Plate 1-2. Spotted salamander (Ambystoma 

maculatum). Spotted salamanders are characteristic 

members of seasonal pool biological communities of the 

mid-Atlantic region.

Seasonal pools’ periodic dry-downs exclude 

permanent populations of predatory fi sh. This 

reduced-predator environment provides critical 

breeding habitat for certain species of amphibians 

whose eggs and larvae would be at increased risk 

of predation in more permanent waters. In the 

mid-Atlantic region, seven species in the mole 

salamander family (Ambystoma spp.), the wood frog 

(Rana sylvatica), and the toad-like eastern spadefoot 

(Scaphiopus holbrookii) depend upon seasonal pools 

for their successful reproduction (Plate 1-2). The 

fairy shrimp (Eubranchipus spp., Streptocephalus 

sealii) and other invertebrates use seasonal pools 

for their complete life cycle (Belk, 1975). Some of 

the species that rely on seasonal pools for optimal 

Plate 1-1. Mid-Atlantic seasonal pool. This seasonal 

forest pool is located in south-central Pennsylvania. 

Important Breeding Habitat 

Supply essential breeding grounds for 

amphibians, including rare, threatened, or 

endangered species. 

Unique Invertebrate Community 

Support a diverse invertebrate fauna, 

including rare species.

Support of Aquatic and Terrestrial 

Food Webs Supply food (amphibian 

and invertebrate biomass) to wildlife 

including amphibians, turtles, snakes, 

birds, and mammals. Serve as “steppingstones” across the landscape for wetlandor aquatic-dependent organisms. 

Box 1-1

Ecological services provided by seasonal pools

Photo: Tim Maret

Photo: Steven M. Roble
2 An Introduction to Mid-Atlantic Seasonal Pools

Seasonal pools are inextricably linked to their 

surrounding terrestrial landscape and support 

aquatic and terrestrial food webs. Bordering and inpool vegetation provide organic material to seasonal 

pools. Bacteria, algae, and fungi colonize this 

vegetative matter, supplying food for invertebrates 

and developing tadpoles. Invertebrates and 

amphibian larvae are, in turn, prey for predatory 

invertebrates and larger-sized amphibian larvae. 

Amphibians and some insect species eventually 

metamorphose, leaving the pools and providing a 

major source of biomass (i.e., food for other wildlife) 

to the surrounding terrestrial habitat. 

Seasonal pools also serve as “stepping-stones” 

through the landscape for animals moving among 

wetlands. By providing feeding and watering 

opportunities, they support local and regional 

biodiversity. Developing amphibian larvae and 

invertebrates in the pools are important prey for 

visiting turtles, snakes, birds, and mammals. 

1.2: Purpose and Scope 

Seasonal pools support biological diversity by 

providing important habitat. However, the same 

qualities that make seasonal pools uniquely valuable 

to wildlife render them especially vulnerable to 

human disturbance. Their small size, surfi cial 

hydrologic isolation, lack of fi sh populations, and 

impermanent water make them less likely to attract 

attention for conservation. Also, they generally are 

not protected by state or federal regulations. Many 

seasonal pools may not meet the strict hydrologic, 

soil, and vegetation requirements to be classifi ed as 

wetlands at the federal or state level (see Cowardin 

et al., 1979) or may fall beneath the minimum 

size requirements to be protected under wetlands 

regulatory programs. 

The United States has lost more than half of its 

original acreage of wetlands due to draining, fi lling, 

dredging, fl ooding, and leveling associated with 

land development and agriculture (Dahl, 1990). 

Although seasonal pools are not comprehensively 

included in studies of wetland loss, partly because 

methods that inform these studies do not work as 

well for identifying relatively small seasonal pools, it 

is highly likely that seasonal pools have been lost at a 

rate equal to or exceeding that of the larger wetlands 

included in these studies. The smaller the wetland or 

pool, the less likely it is to fall under the jurisdiction 

of federal or state wetlands regulations and the 

easier it can be fi lled-in or drained. It is likely that 

pools continue to be lost at a rapid pace in the midAtlantic region. 

The purpose of this publication is to introduce 

readers to seasonal pool ecology and conservation 

in the mid-Atlantic region, which is comprised of 

Delaware (Del.), Maryland (Md.), New Jersey (N.J.), 

Pennsylvania (Pa.), Virginia (Va.), West Virginia (W. 

Va.), and the District of Columbia (D.C.). For many 

readers, seasonal pools will be a new subject area or 

serve as a new synthesis of ecological concepts. 

This publication presents a working defi nition for 

seasonal pools, describes landscape settings and 

vegetative communities of seasonal pools, and 

explores the seasonal pool ecosystem. Following 

an introduction to seasonal pools and their fauna, 

conservation challenges facing resource managers 

and land-use planners wanting to conserve seasonal 

pools are considered. The authors then put forward 

recommendations for future directions in the 

management of seasonal pool resources in the midAtlantic region. 

A pictorial Field Guide to mid-Atlantic seasonal pool 

amphibians, invertebrates, amphibian larvae, and 

amphibian egg masses is provided to aid readers in 

the fi eld. The Appendices present information on 

techniques and references for surveying seasonal 

pools. 
Section 1: Introduction to Seasonal Pools 3

Surfi cial Hydrologic Isolation No permanent surface water connections 

to other water bodies.

Periodic Drying Water levels generally fl uctuate by 

season; pools experience drying or 

lowered water levels on a regular basis 

(frequency ranges from every year to just 

drought years).

Small Size and Shallow Depth Small area and shallow depth compared 

to other productive aquatic habitats (such 

as lakes and types of wetlands).

Distinctive Biological Community Support animals that are adapted to 

seasonal pool drying; support the 

breeding of animals that reproduce 

optimally without fi sh populations; do 

not support permanent populations of 

predatory fi sh. 

Box 1-2

Defi nition of a seasonal pool

1.3: Defi nition of “Seasonal Pool” 

In the mid-Atlantic region and elsewhere, seasonal 

pools display tremendous diversity in terms 

of landscape setting, surrounding vegetative 

community, hydrological source (groundwater, 

surface runoff, rainfall, snowmelt), hydroperiod, and 

faunal communities, among other variables. The 

defi nition of a seasonal pool must be broad enough 

to encompass this variation. 

For the purposes of this publication, we defi ne 

seasonal pools based on four distinguishing features: 

surfi cial hydrologic isolation, periodic drying, small 

size and shallow depth, and distinctive biological 

community (Box 1-2; cf. Wiggins et al., 1980, 

Calhoun and Klemens, 2002; Zedler, 2003; Calhoun 

and deMaynadier, 2004; Colburn, 2004).

 

Surfi cial Hydrologic Isolation

Isolation from other surface waters is one 

of the defi ning characteristics of seasonal 

pools. The lack of permanent surface water 

connections protects pools from successful 

invasion by predatory fi sh. There is a range in 

the degree of isolation of pools, however. Some 

pools are completely surrounded by terrestrial 

environment with the nearest aquatic habitat a 

half-mile or farther away, while other pools may 

occur within a larger wetland complex.

Seasonal pools, despite being isolated from 

permanent surface water connections, are very 

much connected to the greater hydrology and 

ecology of the landscape. Isolated pools may 

receive their water from rainwater, surface water 

run-off, snowmelt, subsurface fl ow, groundwater, 

and possibly intermittent streams (Tiner, 

2003b; Whigham and Jordan, 2003; Winter and 

LaBaugh, 2003). Seasonal pools are connected 

biologically to both aquatic and terrestrial 

habitats by the movement of animals (Gibbons, 

2003; Leibowitz, 2003). 

Periodic Drying

Seasonal pools are water bodies that experience 

alternating periods of fi lling and drying. Pools 

in the Northeast, including the mid-Atlantic 

region, typically begin to fi ll with water in midautumn to early winter due to the onset of fall 

rains and decreased water uptake by plants (i.e., 

the rate of evapotranspiration by trees lessens 

due to leaf senescence) (Phillips and Shedlock, 

1993; Brooks, 2004). However, some seasonal 

pools may not begin fi lling until late winter or 

early spring. Most seasonal pools reach their 

maximum depth and size in the spring due 

to snowmelt and spring rains. As spring and 

summer progress with increasing temperatures 

and rates of evapotranspiration by trees and 

other vegetation, water levels decrease and pools 

may dry completely (Plate 1-3; Fig. 1-1; Brooks, 

2004). 
4 An Introduction to Mid-Atlantic Seasonal Pools

0

5

10

15

20

25

30

35

40

45

Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep

Water depth of pool 

(cm)

Precipitation may begin filling the 

pool in fall or early winter. 

Additionally, the loss of leaves from 

trees in the fall decreases the 

amount of water that is lost from the 

pool through evapotranspiration.

Pools reach their 

maximum depth in early 

to mid spring through the 

combination of spring 

rain, snowmelt, and 

groundwater inputs.

Pools begin decreasing in size and 

depth in late spring through early fall 

due to increased temperatures, 

decreased precipitation, and 

increased evapotranspiration. They 

may eventually dry out completely. 

Figure 1-1. Hydrograph of a seasonal pool.* The water depth of a seasonal pool is shown according 

to month of year. This hydrograph is meant to refl ect a typical seasonal pool; individual pools will 

have different depths and dates of fi lling and drying due to the characteristics of pool depressions and 

precipitation and temperature patterns. 

* Approximate water depths and dates were derived from Brooks (2004), Rowe and Dunson (1993), and datasets of the U.S. 

Geological Survey Amphibian Research and Monitoring Initiative - Northeast (USGS ARMI-NE, unpublished data).

Plate 1-3. A seasonal pool’s wet stage and dry stage. A seasonal pool in Rock Creek Park, D.C., is 

shown (A) in spring when the pool is full of water and (B) in fall when the pool has dried. 

Seasonal pools display considerable variation in 

hydroperiods (length of time that a pool is fi lled 

with water) and water levels (depth at which the 

pool is fi lled) across the landscape (Williams, 1987; 

Semlitsch, 2000). The hydroperiod is the most 

powerful abiotic factor determining the composition 

of a seasonal pool community (Wiggins et al., 

1980; Skelly, 1997; Morey, 1998). The differences 

between pools are due to regional climatic patterns 

and characteristics of each pool’s depression and 

watershed (Brooks and Hayashi, 2002; Winter and 

LaBaugh, 2003). In addition to these inter-pool 

differences, a seasonal pool has intra-pool hydrologic 

variability, with varying hydroperiods and water 

levels over time, depending upon the season and the 

weather conditions (Plate 1-3; Fig. 1-1; e.g., Rowe and 

Dunson, 1993; Semlitsch et al., 1996; DiMauro and 

Hunter, 2002). 

A B

Photos: USGS PWRC
Section 1: Introduction to Seasonal Pools 5

Ephemeral Pools 

Formed by intense periods of precipitation; 

hydroperiods less than two months. 

Annual Pools 

Dry annually in typical years; hydroperiods 

from 2 months to 12 months. 

Semipermanent Pools 

Undergo seasonal fl uctuations in water levels; 

do not dry annually; hydroperiods of greater 

than 12 months. 

The umbrella term, “seasonal pool,” that will be 

primarily used in this publication, may be further 

divided into three general types according to length 

of hydroperiod, which may provide insight into 

their respective biological communities: ephemeral 

pools, annual pools, and semipermanent pools (Box 

1-3). Due to differences in precipitation and weather 

from year to year, pools have different durations and 

timing of fl ooding from one year to the next. Thus, 

the designation of a pool type based on hydroperiod 

is for provisional descriptive purposes only. 

Pools with hydroperiods of less than two months 

during years of average rainfall are “ephemeral 

pools.” They are formed by intense periods of 

precipitation. Ephemeral pools may be especially 

valuable to species of clam shrimp (Class 

Branchiopoda) and other invertebrates as well as 

the reproduction of eastern spadefoots (Scaphiopus 

holbrookii).

Box 1-3

Types of seasonal pools based on hydroperiod

in water levels and dry in years of relatively low 

precipitation. Their surfi cial hydrologic isolation 

and periods of very shallow and anoxic waters still 

preclude permanent populations of predatory fi sh, 

thus they may support seasonal pool-dependent 

organisms. However, they may not support 

organisms that depend upon complete dry-downs, 

such as fairy shrimp. In addition, they may harbor 

higher populations of predators, such as aquatic 

salamanders and large-sized invertebrates (Semlitsch 

et al., 1996; Skelly, 1997; Semlitsch, 2003).

Small Size and Shallow Depth

Most seasonal pools are very small compared to 

ponds and lakes, which makes them more vulnerable 

to pressures from development but does not make 

them less valuable from a biological standpoint. 

Their relatively small area and shallow depth are 

what facilitates their dry periods or drawdowns 

(Brooks and Hayashi, 2002). Their shallow depth 

allows pools to warm rapidly, particularly important 

for amphibians breeding during late winter and early 

spring (Colburn, 2004). 

According to the New Jersey Division of Fish and 

Wildlife, most seasonal pools in New Jersey are less 

than 0.25 acres (1,012 m2

) in area (Tesauro, 2004). 

On the Delmarva Peninsula, seasonal pools are 

reported to be typically less than 0.4 acres (1,619 m2

) 

in size (Phillips and Shedlock, 1993). Many pools in 

the mid-Atlantic region are much smaller than these 

high-range fi gures suggest. In 2004, 134 seasonal 

pools of natural origin with standing water and 

containing wood frog and/or spotted/blue-spotted 

salamander egg masses were surveyed at National 

Parks and National Wildlife Refuges in the midAtlantic as part of the USGS ARMI-NE program. 

Pool area (maximum length x maximum width) 

averaged 0.09 acre (379 m2

) and ranged from 54 ft2

to 1.1 acres (5 to 4,350 m2

), with 78% of the pools 

less than 0.1 acre (400 m2

). Pool maximum depth 

averaged 15.4 inches (39 cm) and ranged from 2.8 

to 78.7 inches (7 to 200 cm), with 69% of the pools 

less than or equal to 15.7 inches (40 cm) maximum 

depth (USGS ARMI-NE, unpublished data). 

Pools that dry annually and have hydroperiods of 

2 months to 12 months are “annual pools.” The 

species composition of an annual pool community 

may be different depending upon the length of the 

hydroperiod. 

At the other end of the spectrum, pools that do not 

dry on an annual basis and have hydroperiods of 

greater than 12 months are “semipermanent pools.” 

They still undergo signifi cant seasonal fl uctuations 
6 An Introduction to Mid-Atlantic Seasonal Pools

Distinctive Biological Community

Seasonal pools of the mid-Atlantic region support 

characteristic communities of animals due to their 

unique hydrology and their lack of permanent 

populations of predatory fi sh. Many seasonal pool 

inhabitants lack defenses against predatory fi sh, 

and thus are primarily restricted to seasonal pools 

(Wilbur, 1980; Kats et al., 1988). For example, larvae 

of species of amphibians that breed in seasonal 

pools may lack the ability to detect and evade fi sh 

by using chemical cues and may be more palatable 

as prey to fi sh as compared to species of amphibians 

that typically breed in permanent waters (Kats 

et al., 1988). Fish predation may annihilate the 

entire brood of larvae of these species, resulting 

in complete reproductive failure (Ireland, 1989). 

However, not all species of fi sh pose direct risks to 

seasonal pool-breeding amphibians; for example, 

some fi sh species feed primarily on plankton 

(Hecnar and M’Closkey, 1997).

Seasonal pool species display structural, 

physiological, or behavioral adaptations to survive 

and/or reproduce in these temporary waters 

(Wiggins et al., 1980; Wilbur, 1980; Williams, 1987). 

Amphibians and some species of invertebrates 

metamorphose and leave the pool before it dries. 

Certain species of invertebrates lay eggs that survive 

the dry period; larvae or adults of some species may 

burrow into the pool bottom. However, when there 

is little rain in the spring, a pool can dry out too 

quickly, causing embryos and amphibian larvae to 

become desiccated and die (Plate 1-4; Shoop, 1974; 

Semlitsch et al., 1988; Rowe and Dunson, 1993; 

Skelly, 1997; Morey, 1998; DiMauro and Hunter, 

2002).

Seasonal pools provide optimal breeding habitat 

for nine species of amphibians across the region, 

including seven species of mole salamanders in 

the family Ambystomatidae as well as two anuran 

species: wood frog and eastern spadefoot (see 

Section 3 and the Field Guide for descriptions and 

photographs of these animals).

Certain invertebrate taxa are common among 

seasonal pool biological communities, including 

crustaceans, mites, and three insect groups (true 

bugs, beetles, and midges) (Williams, 1987; 

Brooks, 2000; Colburn, 2004). The fairy shrimp 

is a characteristic member of some seasonal pool 

biotic communities; seasonal pools are the primary 

habitats in which fairy shrimp species of the midAtlantic region occur. 

Depending on the weather, there may be years 

when little or no breeding activity occurs in a pool 

(Semlitsch et al., 1996). However, seemingly “empty” 

pools may still support tremendous biodiversity in 

years with favorable precipitation and temperature 

patterns. 

Seasonal pools may or may not be vegetated. 

Although in-pool vegetation is not essential for 

their role as important animal habitat, some 

seasonal pools may support rare or endemic species 

of vegetation, such as the Virginia sneezeweed 

(Helenium virginicum), a state-listed threatened 

plant endemic to sinkhole ponds of Virginia. More 

research is needed to catalog these pool-dependent 

species of fl ora.

Plate 1-4. Seasonal pools drying before metamorphosis. Seasonal pools may dry before metamorphoses 

of amphibians are complete. (A) A spotted salamander 

(Ambystoma maculatum) egg mass remains in a dry 

seasonal pool in Rock Creek Park, D.C. (B) Wood frog 

(Rana sylvatica) tadpoles are left behind when a pool 

dries up in Shenandoah National Park, Va. 

A

B

Photos: USGS PWRC
2

Section 2: The Greater Seasonal Pool Ecosystem 7

THE GREATER SEASONAL POOL ECOSYSTEM

The greater seasonal pool ecosystem is considerably 

larger than the seasonal pool itself. It extends 

outwards into the terrestrial landscape via biological 

connections and the watershed via hydrologic 

linkages. This section provides an overview of 

the variety of landscape settings and surrounding 

vegetative communities, explores the greater 

seasonal pool ecosystem, and examines the general 

life histories of seasonal pool-dependent fauna to 

elucidate the nature of their interactions with the 

seasonal pool ecosystem. 

2.1: Setting and Vegetation of 

Seasonal Pools

The mid-Atlantic region is a physiographically 

diverse area of the United States, encompassing 

the extremes of the low, fl at, sandy mid-Atlantic 

coastal plain to the greater than 5000 foot peaks 

of the southern Blue Ridge Mountains of Virginia. 

For example, Delmarva bays that are found on the 

Delmarva Peninsula coastal plain of Maryland 

and Delaware (Box 2-1) are very different 

physiographically as compared to the seasonal 

sinkhole ponds of the Shenandoah Valley of the Blue 

Ridge Mountains (Buhlmann et al., 1999). Seasonal 

pools of the mid-Atlantic refl ect physiographic 

diversity in their wide variety of landscape settings 

and surrounding vegetative communities. 

Seasonal pools can be found in three general 

landscape settings: surrounded by upland, wetland, 

or fl oodplain. Pools surrounded by upland are 

islands of aquatic habitat within a terrestrial 

landscape; pools surrounded by wetlands are part 

of a larger wetland complex; pools surrounded 

by fl oodplain are occasionally linked to a riverine 

system. 

Four basic classes of seasonal pools are described 

below (seasonal forest pools, seasonal open-canopy 

pools, seasonal scrub-shrub pools, and seasonal 

forested wetland pools) based on their surrounding 

vegetative community, with short lists of common, 

but certainly not inclusive, species of vegetation that 

may be found in or around these seasonal pools 

(species were selected by referring to Tiner and 

Burke, 1995; Rawinski, 1997; Buhlmann et al., 1999; 

Sipple 1999; Zankel and Olivero, 1999; Colburn, 

2004). Compositions of vegetative communities 

vary from site to site due to local environmental and 

historical conditions. Some pools may fall into more 

than one class or may not easily be placed into one. 

Additionally, vegetative communities are not static 

– they may change across the seasons and over the 

long-term (Tiner and Burke, 1995; Rawinski, 1997; 

Colburn, 2004).

Seasonal Forest Pools

Seasonal forest pools are isolated depressions 

surrounded by upland deciduous, mixed deciduousconiferous, or coniferous forest (Plate 2-1). These 

pools may or may not be clustered in the landscape. 

Trees that can tolerate seasonally-saturated soils, 

such as white oak (Quercus alba), chestnut oak 

(Quercus prinus), willow oak (Quercus phellos), 

pin oak (Quercus palustris), American elm (Ulmus 

americana), loblolly pine (Pinus taeda), sweet gum 

(Liquidambar styracifl ua), American beech (Fagus 

grandifolia), and sourwood (Oxydendrum arboreum), 

or trees with fl ood-resistant adaptations (e.g., 

buttresses, stilt roots) may be found around the 

edges of the pool depression; a few may be found in 

the pool itself, especially during high water levels. 

Seasonal forest pools are partially or completely 

Plate 2-1. Seasonal forest pool. This seasonal forest 

pool is located in western Virginia.

Photo: Lesley J. Brown
8 An Introduction to Mid-Atlantic Seasonal Pools

shaded by the overhanging tree canopy but there 

is little or no plant growth in the pool depression 

itself (Tiner and Burke, 1995; Rawinski, 1997; Sipple, 

1999; Colburn, 2004). 

Seasonal Open-Canopy Pools

Seasonal open-canopy pools have open canopies 

that allow full sunlight to reach the pool (Plate 2-2). 

The pools may be surrounded by upland, situated 

within a larger wetland matrix, or in a fl oodplain. 

They may be without vegetation or may be vegetated 

with non-woody plant species. Emergent plants that 

grow in these pools may include grasses (e.g., manna 

grasses (Glyceria spp.), panic grasses (Panicum spp.), 

giant plumegrass (Erianthus giganteus), rice cutgrass 

(Leersia oryzoides)), sedges and rushes (e.g., sedges 

(Carex spp.), creeping rush (Juncus repens), woolgrass 

bulrush (Scirpus cyperinus), three-way sedge 

(Dulichium arundinaceum)), and herbs (e.g., Virginia 

meadow beauty (Rhexia virginica), marsh St. John’swort (Triadenum virginicum), Virginia chain fern 

(Woodwardia virginica)). 

Seasonal Scrub-Shrub Pools

Seasonal scrub-shrub pools are dominated by 

shrubs or young trees less than 20 feet tall (6 m) 

growing in the seasonal pool depression (Plate 

2-3). Scrub-shrub pools may be surrounded by 

upland forest, part of a larger wetland system, or 

in a fl oodplain. Vegetation may include common 

greenbrier (Smilax rotundifolia), highbush blueberry 

(Vaccinium corymbosum), buttonbush (Cephalanthus 

occidentalis), fetterbush (Leucothoe racemosa), 

dangleberry (Gaylussacia frondosa), swamp azalea 

(Rhododendron viscosum), sweet pepperbush (Clethra 

alnifolia), winterberry (Ilex spp.), alders (Alnus spp.), 

and water willow (Decodon verticillatus). 

Plate 2-3. Seasonal scrub-shrub pool. This seasonal 

scrub-shrub pool is located at U.S. Department of 

Agriculture’s Beltsville Agricultural Research Center, 

Md.

Plate 2-2. Seasonal open-canopy pool. This 

seasonal open-canopy pool is located in south-central 

Pennsylvania.

Photo: USGS PWRC

Photo: Tim Maret
Section 2: The Greater Seasonal Pool Ecosystem 9

Seasonal Forested Wetland Pools

Seasonal forested wetland pools are dominated 

by fl ood-tolerant trees greater than 20 feet tall (6 

m) growing in the pool basin (Plate 2-4). Seasonal 

forested wetland pools may be surrounded by upland 

forest or may be situated within a larger wetland 

matrix, fl oodplain, or oxbow of a river. Trees may 

include sweet gum (Liquidambar styracifl ua), 

swamp black gum (Nyssa bifl ora), black gum (Nyssa 

sylvatica), laurel oak (Quercus laurifolia), overcup 

oak (Quercus lyrata), loblolly pine (Pinus taeda), 

red maple (Acer rubrum), willow oak (Quercus 

phellos), sourwood (Oxydendrum arboreum), water 

oak (Quercus nigra), pin oak (Quercus palustris), 

American elm (Ulmus americana), American holly 

(Ilex opaca), sweet bay (Magnolia virginiana), willows 

(Salix spp.), Atlantic white cedar (Chamaecyperis 

thyoides), and green ash (Fraxinus pennsylvanica). 

Plate 2-4. Seasonal forested wetland pool. A 

seasonally fl ooded swamp forest of sweetgum 

(Liquidambar styracifl ua), red maple (Acer rubrum), 

and swamp tupelo (Nyssa bifl ora). This pool is located 

in North Landing River Natural Area Preserve, City of 

Virginia Beach, Va.

Box 2-1

Example of regional seasonal pools: Delmarva bays 

Delmarva bays are an example of a type of seasonal 

pool that is specifi c to an area of the mid-Atlantic 

region. The Delmarva Peninsula is the projection of 

land into the Chesapeake Bay that encompasses the 

entire state of Delaware and portions of Maryland 

and Virginia. On the Delmarva Peninsula, the 

landscape is pockmarked with thousands of isolated 

depressional wetlands or pools. These depressions 

are known by many names, such as Delmarva bays, 

Delmarva potholes, and whale wallows (Sipple, 

1999). They are also sometimes categorized 

within the larger category of coastal plain ponds or 

equated with Carolina bays. ‘Bay’ refers to the trees 

that are often found in these habitats: sweet bay 

(Magnolia virginiana), red bay (Persea borbonia), 

and loblolly bay (Gordonia lasianthus) (Sipple, 

1999). The coastal plain’s relatively fl at topography 

favors the formation of seasonal pools, fed by 

both groundwater and high levels of precipitation 

experienced in this region (Tiner, 2003a). 

Delmarva bays are of variable shapes and sizes – 

elliptical, circular, or irregular with long-axes ranging 

in length from less than 305 ft to 3050 ft (100 m 

to 1 km) (Stolt and Rabenhorst, 1987). Their longaxes are often oriented from north to south. They 

generally have no standing water from midsummer 

to early winter. Delmarva bays may form seasonal 

open-canopy pools (known as ‘glades’) with Walter’s 

sedge (Carex walteriana), giant plumegrass, twigrush 

(Cladium mariscoides), and maidencane (Panicum 

hemitomon); seasonal scrub-shrub pools with 

buttonbush and water willow; and seasonal forested 

wetland pools with red maple, sweet gum, and oaks 

(Sipple, 1999). 

Delmarva bays are particularly abundant in the 

central area of the Delmarva Peninsula along the 

border between Maryland and Delaware, in Queen 

Anne’s County and Caroline County in Maryland 

and Kent County in Delaware (Stolt and Rabenhorst, 

1987). Delmarva bays’ abundance over the landscape 

makes them important for surface water storage and 

helps control local fl ooding. During wet seasons, they 

serve as storage for groundwater discharge; during 

dry seasons, they serve as sources of groundwater 

recharge (Phillips and Shedlock, 1993). Delmarva 

bays serve as important wildlife habitat, and support 

many of the species described in Section 3.

Photo: Gary P. Fleming
10 An Introduction to Mid-Atlantic Seasonal Pools

2.2: Life Zones of Seasonal Pools

The seasonal pool ecosystem can be thought of as 

being composed of three integrated components, 

or life zones: the seasonal pool depression, the 

seasonal pool envelope (100 ft (30.5 m) radius 

from pool edge), and the seasonal pool terrestrial 

habitat (1000 ft (305 m) radius from the pool 

edge) (Fig. 2-1; cf. Semlitsch, 1998; Calhoun 

and Klemens, 2002; Calhoun and deMaynadier, 

2004). Conceptualization of three discrete but 

Figure 2-1. Seasonal pool aerial view delineating three life zones.* The seasonal pool depression is the entire 

area that fi lls with water during highest water levels. The seasonal pool envelope is the area immediately surrounding 

the pool depression, extending 100 ft † (30.5 m) beyond the edge of the depression. The seasonal pool terrestrial 

habitat is the area surrounding the pool that extends 1000 ft ‡ (305 m) beyond the edge of the depression (inclusive 

of the seasonal pool envelope).

† This width is based on the management zone designed by Calhoun and Klemens (2002). 

‡ This width was determined so as to encompass the movements and habitats of pool-breeding salamanders (e.g., Semlitsch, 1998; Faccio, 2003) and to 

account for their high sensitivity to the amount of forest cover within this zone (e.g., Homan et al., 2004; Porej et al., 2004; Herrmann et al., 2005). However, 

characteristics of the landscape (e.g., forest cover, road densities) at greater distances from the pool beyond this life zone may also affect seasonal pool fauna 

(Homan et al., 2004; Porej et al., 2004; Herrmann et al., 2005). Additionally, juvenile wood frogs may migrate to other pools at distances signifi cantly beyond 

this life zone (average of 3750 ft (1140 m); Berven and Grudzien, 1990).

* Symbols used for diagram courtesy of the Integration and Application Network, University of Maryland Center for Environmental Science.

interdependent physical areas provides insight into 

the overall functioning of the greater ecosystem 

and allows tailored conservation strategies to be 

developed (e.g., Calhoun and Klemens, 2002; 

Calhoun and deMaynadier, 2004). All three zones 

provide essential services that contribute to the 

seasonal pool ecosystem. The three seasonal pool life 

zones and the more prominent activities that they 

host are briefl y described below. 
Section 2: The Greater Seasonal Pool Ecosystem 11

Seasonal Pool Depression

The seasonal pool depression (also known as the 

seasonal pool basin) is the area that fi lls with water 

during highest water levels (Fig. 2-1). If there is no 

standing water, other visual clues may indicate the 

pool depression (Box 2-2; Plate 2-7). The seasonal 

pool depression is the epicenter of the seasonal 

pool ecosystem in late winter and spring, hosting 

amphibian breeding, amphibian egg and larval 

development, invertebrate life cycles, and wildlife 

feeding. 

Amphibian Breeding. Mole salamanders 

(Ambystoma spp.) and wood frogs migrate 

to the seasonal pool depression from their 

overwintering terrestrial habitat from late winter 

to spring, with the exception of the marbled 

salamander (Ambystoma opacum), which 

migrates to the depression in the fall. The exact 

migration times or dates depends on the species, 

region, and weather. Courtship and mating takes 

place in the seasonal pool depression (Plate 2-5). 

attached to vegetation or woody debris below the 

water surface (Petranka, 1998). After hatching, 

salamander larvae and tadpoles develop in the 

pools. Salamander larvae eat zooplankton, 

invertebrates, and, for larger individuals, other 

amphibian larvae (Petranka, 1998); tadpoles 

primarily eat algae and detritus, although they 

may also eat smaller amphibian larvae and eggs. 

Plate 2-6. Release of spotted salamander eggs. 

These female salamanders are laying egg masses in the 

water of a seasonal pool.

Invertebrate Life Cycles. Seasonal pools provide 

habitat for a wide variety of invertebrate species. 

The soil at the bottom of seasonal pools may 

contain resting eggs from species of crustaceans, 

including fairy shrimp, clam shrimp, and seed 

shrimp, and arthropods, including caddisfl ies 

(Dodson and Frey, 1991; Hilsenhoff, 1991; Smith, 

2001). Adult amphibious snails, fi ngernail clams, 

and amphipods may also survive dry conditions 

or overwinter by burrowing into sediments and 

organic debris (Smith, 2001). 

Support of Terrestrial Food Webs. Invertebrates, 

amphibians, reptiles, birds, and mammals 

come to the pool depression to feed (Winfi eld 

et al., 1981; Brooks and Doyle, 2001; Kenney 

and Burne, 2001; Biebighauser, 2002; Colburn, 

2004). Amphibian egg masses, invertebrate and 

amphibian larvae, and emerging insects and 

amphibians provide a signifi cant food source 

for visiting predators. Seasonal pools serve 

as important feeding and watering sites for 

wetland- or aquatic-dependent animals traveling 

across the landscape. 

Plate 2-5. Amplexus between a male and female 

wood frog (Rana sylvatica). The male wood frog clasps 

the female wood frog from behind while mating. There 

are wood frog eggs on either side of the mating pair.

Amphibian Egg and Larval Development. 

Depending on the species, female pool-breeding 

amphibians lay their eggs singly, in strings, in 

sheets, or as discrete masses immediately or a 

few days after mating (Plate 2-6). Eggs and egg 

masses of seasonal pool-breeders are usually 

Photo: Steven M. Roble

Photo: Steven M. Roble
12 An Introduction to Mid-Atlantic Seasonal Pools

Seasonal Pool Envelope

The seasonal pool envelope is the terrestrial 

habitat immediately surrounding the pool; it is a 

management zone that extends approximately 100 

feet (30.5 m) from the pool edge (Fig. 2-1; Calhoun 

and Klemens, 2002; Calhoun and deMaynadier, 

2004). This area supports activities related to 

amphibian breeding, provides terrestrial habitat to 

juvenile and adult amphibians, and plays a large role 

in regulating water quality.

Amphibian Breeding. During the amphibian 

breeding season (from late winter to spring for 

most species), high densities of adult amphibians 

may occupy the seasonal pool envelope (Plate 

2-8; Calhoun and Klemens, 2002). They spend 

their days hidden in this area near the edge 

of the seasonal pool or in the pool itself, and 

their nights in the pool engaged in breeding 

activities. Male amphibians may arrive up to 

several days or weeks earlier than females and 

wait for females to arrive in this area (Bishop, 

1941; Shoop, 1960; Semlitsch, 1981). Marbled 

salamanders, unlike the other species in the mole 

salamander family, breed in the late summer or 

fall and may mate in the seasonal pool envelope. 

Male marbled salamanders often intercept 

females en route to the breeding pools, and 

initiate courtship in the pool envelope before the 

females reach the pool depression (Bishop, 1941; 

Krenz and Scott, 1994). 

Box 2-2

Recognizing dry seasonal pools*

If there is no standing water, other visual clues 

can be used to identify seasonal pools that fi ll 

with water in another season.

Characteristic Topography

 Depressions in otherwise fl at topography

 “Pit-and-mound” topography

Clues from Seasonal Pool Biota

 Fingernail clams and clam shells

 Caddisfl y cases

 Snails and snail shells

 Fairy shrimp eggs

Evidence of Water

 Stained or sediment-covered leaves

 Trees with fl ood-resistant adaptations (e.g., 

buttresses, stilt roots)

 Sphagnum moss, ferns

 Wetland plants growing in dry soil

 Wetland (hydric) soils

 Water stains on trees

Plate 2-7. Recognizing dry seasonal pools. Water 

stains at the base of trees presents evidence that this 

area fi lls with water. This seasonal pool is located at the 

Patuxent Research Refuge, Laurel, Maryland.

Plate 2-8. Spotted salamanders at pool edge. These 

salamanders are spending their daylight hours during 

the breeding season under a cover object in the mud at 

the margin of a seasonal pool. 

* Colburn, 1997; Tappan, 1997; Calhoun, 2003

Photo: USGS PWRC

Photo: USGS PWRC
Section 2: The Greater Seasonal Pool Ecosystem 13

Juvenile and Adult Amphibian Habitat. From 

summer to fall, the seasonal pool envelope 

is occupied by large numbers of recently 

metamorphosed juvenile frogs and salamanders. 

They may burrow into the mud near the pool 

edge or hide beneath rocks and logs to survive 

dry weather before making their emigration 

from the pools to their overwintering habitat 

(Richmond, 1947; Shoop, 1974). Wintering 

juvenile and adult wood frogs occur in greatest 

densities within 30 m of pools and are highly 

sensitive to disturbances in this area (Homan et 

al., 2004; Regosin et al., 2005).

Water Quality. The seasonal pool envelope plays 

a large role in regulating seasonal pool water 

quality. Soil buffers run-off and snowmelt before 

it enters the pool (Gascon and Planas, 1986). 

Vegetation (tree roots and ground cover) traps 

sediment before it enters the pool. Overhanging 

vegetation regulates pool temperature and 

supplies organic material to the pool depression; 

leaf litter serves as food for fungi, bacteria, and 

invertebrates (Colburn, 2004). Vegetation also 

infl uences a pool’s hydrologic regime – trees and 

shrubs withdraw water from the pools, especially 

in the spring and summer.

Seasonal Pool Terrestrial Habitat

Seasonal pool terrestrial habitat is the area that 

extends 1000 ft (305 m) from the edge of the 

seasonal pool depression (Fig. 2-1). The portion of 

this life zone that remains forested or unimpacted 

by human activities provides habitat to poolbreeding amphibians and other wildlife, serves as a 

terrestrial corridor between pools, and plays a role in 

regulating water quality. 

This management zone encompasses the habitat 

of over 95% of populations of pool-breeding 

salamanders (Semlitsch, 1998; Faccio, 2003), 

although this area is not suffi cient to encompass all 

movements of seasonal pool-breeding amphibians 

(e.g., juvenile wood frog migrations, Berven and 

Grudzien, 1990). Also, the seasonal pool biological 

community may be infl uenced by characteristics of 

the landscape (e.g., amount of forest cover, densities 

of roads) well beyond the seasonal pool terrestrial 

habitat zone (Homan et al., 2004; Porej et al., 2004). 

Amphibian and Other Wildlife Habitat.

Seasonal pool-breeding amphibians of the midAtlantic region spend approximately 90% of 

their juvenile and adult lives in the terrestrial 

landscape (Semlitsch, 1998), and exhibit seasonal 

variation in terrestrial habitat use. During the 

winter, wood frogs fi nd shelter and hibernate 

in upland forests; during their more active 

period, they forage and fi nd shelter in moist 

lowland forests (Hulse et al., 2001; Regosin et 

al., 2003b). Spotted salamanders may occur at 

uniform densities up to and exceeding 984 ft 

(300 m) away from seasonal pools (Homan et 

al., 2004). Seasonal pool-breeding amphibians 

play important roles in forest ecology, as prey for 

wildlife and as predators of invertebrates. In a 

given area of forest, they may comprise a higher 

biomass than the breeding birds and small 

mammals combined (Windmiller, 1996). Many 

other species of wildlife inhabit the seasonal 

pool terrestrial habitat, including snakes, turtles, 

birds, and terrestrial amphibians. They feed 

on the resources produced in the seasonal pool 

(Winfi eld et al., 1981; Brooks and Doyle, 2001; 

Kenney and Burne, 2001; Biebighauser, 2002; 

Colburn, 2004). 

Biological Corridor. The terrestrial forested 

habitat functions as a biological corridor, 

whereby animals can travel between pools. Poolbreeding amphibians and other animals may 

disperse from one pool to another. 

Water Quality. The water quality of the pool will 

be determined by the entire watershed, which 

will extend into the seasonal pool terrestrial 

habitat and possibly even farther, depending 

upon the characteristics of the watershed and the 

source of the water. 
14 An Introduction to Mid-Atlantic Seasonal Pools

2.3: Life Histories of Seasonal PoolDependent Organisms

Seasonal pool-dependent animals have developed 

behavioral (e.g., effective immigration and 

emigration strategies), physiological, or structural 

adaptations that allow them to survive and/or 

reproduce in the highly dynamic environment of 

seasonal pools (Wiggins et al., 1980; Williams, 

1987). Seasonal pool-dependent animals may be 

classifi ed into three general life history classes: 

migratory breeders, non-breeding migrants, and 

permanent residents (based on Colburn, 2004; 

builds upon and modifi es previous classifi cation 

systems of Wiggins et al., 1980; Williams, 1987). 

This classifi cation system is presented below, in the 

context of mid-Atlantic seasonal pools. 

Amphibian migratory breeders have biphasic 

life cycles, requiring both aquatic and terrestrial 

habitats (Semlitsch, 1998, 2003). Early stages 

of development are spent as eggs and larvae in 

seasonal pools. The transition from an aquatic to a 

terrestrial life stage occurs at metamorphosis, when 

amphibians emerge from their natal pools and enter 

the terrestrial habitat. 

As adults, they return to seasonal pools from their 

terrestrial habitats to breed. Once having bred in a 

particular pool, adult wood frogs have been found to 

be very faithful to their pools (Berven and Grudzien, 

1990). There is evidence that other pool-breeding 

amphibians exhibit similar levels of breeding pool 

fi delity (e.g., Ambystoma maculatum, Scott, 1994) 

returning to the same pools and following the same 

migration paths. Males arrive at breeding pools 

earlier and stay later than females (Bishop, 1941; 

Shoop, 1960; Semlitsch, 1981). 

Dispersal between local populations occurs when 

animals breed in pools other than their natal pools. 

Dispersal in wood frogs and other seasonal poolbreeding amphibians is age-specifi c, with juveniles 

accounting for most or all of the movements between 

ponds (Berven and Grudzien, 1990). Wood frogs 

Box 2-3

Life history of pool-breeding amphibians

Migratory Breeders

“Migratory breeders” are those animals that breed in 

seasonal pool depressions during the fl ooded phase 

and vacate pools during the dry phase (Colburn, 

2004). The most visible members of this life history 

grouping are pool-breeding amphibians (Box 2-3; 

see Section 3 for more information). 

Besides amphibians, some invertebrate species rely 

on this life history strategy as well. Limnephilid 

caddisfl y adults spend summers in caves and tree 

holes and return to the pools to breed (Colburn, 

2004). Certain species of predaceous diving beetles, 

backswimmers, and water boatman spend portions 

of their life cycles in permanent water bodies away 

from seasonal pools (Colburn, 2004).

may emigrate more than 3750 ft (1140 m) from their 

natal pools to breed as adults in other pools (Berven 

and Grudzien, 1990). 

The behavior and habitat requirements of the 

terrestrial stage of pool-breeding amphibians are 

not fully understood, primarily due to the logistical 

diffi culties in their study and the amphibians’ 

nocturnal and belowground habits (Petranka, 1998; 

Dodd and Smith, 2003; Semlitsch, 2003). Poolbreeding amphibians must keep their skin cool 

and moist. Thus microclimates play a large role in 

the suitability of a particular habitat for amphibians 

(Gibbs, 1998; Guerry and Hunter, 2002); mature 

forests provide appropriate microclimates (Semlitsch, 

1981; Petranka et al., 1994; deMaynadier and Hunter, 

1999; Rothermel and Semlitsch, 2002; Faccio, 2003). 

Mole salamanders require suffi cient belowground 

refugia, which provide protection from predators and 

freezing temperatures (Madison, 1997; Regosin et 

al., 2003a). Mole salamanders may emigrate more 

than 650 ft (200 m) from their breeding pools to their 

terrestrial habitat (Semlitsch, 1981; Madison, 1997). 

Females of pool-breeding amphibian populations 

are more likely to overwinter at greater distances 

away from pools compared to males (Regosin et al., 

2003a, b).
Section 2: The Greater Seasonal Pool Ecosystem 15

Non-Breeding Migrants

“Non-breeding migrants” are those animals that 

migrate to seasonal pools for feeding, rather than 

breeding, a behavioral adaptation used to exploit 

seasonal pool resources (Williams, 1987; Colburn, 

2004). This group may include species of predaceous 

diving beetles, turtles, snakes, birds, and mammals. 

Freshwater turtles that frequent seasonal pools 

generally feed on algae, terrestrial and aquatic plants, 

and invertebrates. Snakes that have aquatic or semiaquatic life histories, such as the ribbonsnake, may 

hunt for amphibians in the water of a seasonal pool. 

Birds and mammals use seasonal pools as sources of 

water and food (see Section 3). 

Permanent Residents

“Permanent residents” are those animals that do not 

spend signifi cant amounts of time away from the 

seasonal pool (Colburn, 2004). Permanent residents 

are those with unique physiological and behavioral 

adaptations to withstand drying and extreme 

temperature changes. Some beetles, fi ngernail 

clams, and other invertebrates spend the dry phase 

or winter season aestivating in the sediment of pool 

depressions. One of the most distinctive inhabitants 

of some seasonal pools, fairy shrimp, as well as 

species of fl atworms, mosquitoes, and beetles, 

survive pool drying as drought-resistant eggs or cysts 

that hatch upon fl ooding (Smith, 2001). This life 

history group also includes insects that spend their 

larval stages in seasonal pools and become aerial as 

adults but do not travel far from pools (Colburn, 

2004).

3

Section 3: Introduction to Seasonal Pool Fauna 17

INTRODUCTION TO SEASONAL POOL FAUNA

3.1: Introduction to Seasonal Pool 

Fauna

Seasonal pools provide important habitats for 

invertebrates, amphibians, reptiles, birds, and 

mammals. Amphibians are among the most 

conspicuous visitors to seasonal pools, especially 

between late winter and summer. During the 

breeding season, congresses of salamanders and 

choruses of frogs provide visual and auditory notice 

of their presence. For a period of time after adults 

breed and return to their terrestrial habitat, egg 

masses and then larvae remain in the pool. 

The hydroperiod of a seasonal pool plays a 

signifi cant role in determining the community 

of animals it will support (Wiggins et al., 1980; 

Semlitsch et al., 1996; Skelly, 1997; Morey, 1998; 

Semlitsch, 2003). A hydroperiod shorter than one 

month will not support the reproduction of most 

seasonal pool-breeding amphibians. Conversely, 

effi cient predators of seasonal pool-dependent 

species, such as aquatic salamanders, bullfrogs, and 

large-sized predatory invertebrates, may potentially 

colonize pools that have longer hydroperiods 

(Thompson et al., 1980; Wilbur, 1980; Semlitsch 

et al., 1996; Skelly, 1997; Semlitsch, 2003). A 

given seasonal pool may be suitable habitat for 

only a subset of seasonal pool-dependent species 

(Zedler, 2003). Hydroperiod affects invertebrate 

community composition, abundance, biomass, and 

biological production (Leeper and Taylor, 1998). 

As characteristics of pools change over time (e.g., 

succession of vegetation, lengthening or shortening 

of hydroperiod), the amphibian and invertebrate 

communities’ species compositions may shift. 

This section introduces the faunal communities 

of seasonal pools. The Field Guide found on pages 

37-68 provides more detailed information on these 

species. It contains descriptions of the physical 

characteristics, behavior, phenology, reproductive 

biology, and geographic range of these species and 

provides photographs to aid in their identifi cation. 

Note: This section and the Field Guide primarily focus 

on the faunal communities of annual pools. Many of 

these animals also successfully inhabit or breed in other 

seasonal pools (i.e., ephemeral pools or semipermanent 

pools). Additional research is needed to adequately 

describe the faunal communities of ephemeral pools 

and semipermanent pools.

3.2: Indicator and Facultative Species

Indicator species rely on seasonal pools as essential 

habitat for a portion of their life cycles. These 

species, sometimes also referred to as obligate 

species, are dependent upon seasonal pools for 

their continued existence (Box 3-1). Indicator 

species have evolved to exploit seasonal pools: they 

respond rapidly to the fi lling of the pool and their 

populations persist through dry periods, due to 

structural, behavioral, or physiological adaptations 

(Wiggins et al., 1980; Williams, 1987; Zedler, 2003). 

Indicator species of annual pools in the mid-Atlantic 

region include nine species of amphibians (seven 

species of mole salamanders, the wood frog, and 

the eastern spadefoot) (Figure 3-1) and a crustacean 

group (the fairy shrimp). As research on the natural 

history of amphibians and invertebrates of seasonal 

pools continues, there may be additional species that 

are determined to be indicators.

Some of the amphibian indicator species may 

sometimes breed in other pool types, such as small 

permanent ponds, road-rut pools, or roadside 

ditches (Petranka, 1998; Hulse et al., 2001; DiMauro 

and Hunter, 2002). However, these alternate 

breeding sites may result in reduced survival 

of eggs and larvae. Roadside ditches and other 

anthropogenic pools may dry too quickly to allow 

species of amphibians to reach metamorphosis 

(DiMauro and Hunter, 2002). More permanent 

pools may harbor fi sh and other vertebrate predators 

that prey heavily on developing invertebrates and 

amphibians (Ireland, 1989). Seasonal pools represent 
18 An Introduction to Mid-Atlantic Seasonal Pools

the most desirable breeding habitat for these 

indicator species because of the higher likelihood of 

successful reproduction.

There are also numerous facultative species that use 

seasonal pools – the more common or signifi cant 

facultative species are included in this section and 

the Field Guide. Facultative species use seasonal 

pools for foraging, shelter, water, or breeding, 

although they can successfully breed in other habitat 

types (Box 3-1). Facultative species of seasonal pools 

in the mid-Atlantic region include many aquatic 

invertebrates, amphibians, turtles, snakes, birds, and 

mammals. 

Box 3-1

Indicator vs. facultative species in seasonal 

pools

Indicator species REQUIRE seasonal pools for 

optimal breeding conditions.

Facultative species USE seasonal pools 

for obtaining food, water, temporary cover, or 

breeding, although they can also successfully 

breed in other habitats.
Section 3: Introduction to Seasonal Pool Fauna 19

Common

Name

Spotted

Salamander

Northern

1/2

Western

1/3

Entire Entire

Entire1

Entire1

Entire1

Entire except

southern

Eastern

Shore

Eastern

Shore &

southern tip2

Entire except

far western

Southern &

eastern;

Eastern Shore

Ambystoma

maculatum

Marbled

Salamander

Ambystoma

opacum

Eastern

Tiger

Salamander

Ambystoma t.

tigrinum

Jefferson

Salamander

Ambystoma

jeffersonianum

BlueSpotted

Salamander

Ambystoma

laterale

Mabee's

Salamander

Ambystoma

mabeei

Mole

Salamander

Ambystoma

talpoideum

Wood

Frog Rana sylvatica

Eastern

Spadefoot

Scaphiopus

holbrookii

Scientific

Name

STATES

Del. Md.

X

X

X

X

X

X

X

Northern

1/3

Northern

1/3

Southern

1/3

Northern

3/4

Entire

Entire

Entire, though

scattered

distribution

in northern 1/2

N.J.

X

X

Entire

Eastern &

southeastern;

scattered

western

distribution

Mainly

eastern &

southeastern

Southeastern

& 1 county

in Shenandoah

Valley

Western

(Blue Ridge,

Valley & Ridge,

Allegheny)

Entire except

southeastern

Southeastern

Isolated

south-central

Va.

X

Entire

Entire

1 county3

Scattered

distribution

southern &

eastern 1/2

Scattered

distribution4

Parts of

eastern &

southcentral

Pa.

X

X

X

Entire

Scattered

distribution

(mainly along

Allegheny)

Entire though

scattered

distribution

Isolated,

scattered

distribution

Mainly

eastern,

southeastern,

 & western

W. Va.

X

X

X

X

 1Not found north of Fall Line in extreme northern Del. (White and White, 2002); 2Extirpated from Charles 

County, Md.; 3Record from Chester County is historical; they are likely extirpated from Pa. (Hulse et al., 

2001); 4Hybrid populations of Jefferson and blue-spotted salamanders may occur in several locations in Pa., 

but genetic analyses need to be conducted to clarify this issue (Hulse et al., 2001).

* Distribution information for the mid-Atlantic states was primarily obtained from the ARMI National Atlas for 

Amphibian Distributions (http://www.pwrc.usgs.gov/armiatlas/) and Petranka (1998). Information on ranges in 

specifi c states was supplemented with Harris (1975) and White and White (2002) for Del. and Md., Schwartz and 

Golden (2002) for N.J., Hulse et al. (2001) for Pa., Martof et al. (1980) and Mitchell and Reay (1999) for Va., and 

Green and Pauley (1987) for W. Va. 

Figure 3-1. Distribution of amphibian indicator species in mid-Atlantic seasonal pools.* Cells marked 

with “X” indicate that the species is not currently present in that state. Fractions indicate the approximate 

proportion of the state in which the species occurs. 
20 An Introduction to Mid-Atlantic Seasonal Pools

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Time as egg Time as adult fairy shrimp Time as larva ( )/paedomorph ( )

Time when metamorphosis is occurring Time as tadpole Time when metamorphosis is occurring

Fairy Shrimp

Spotted

Salamander

Marbled

Salamander

Eastern

Spadefoot

Wood Frog

Mole

Salamander

Mabee's

Salamander

Blue-spotted

Salamander

Jefferson

Salamander

Eastern Tiger

Salamander

Figure 3-2. Breeding phenologies of seasonal pool indicator species.* This chart displays the life stages 

of indicator species in the mid-Atlantic region according to time of year. The combined length of the illustration and the green/white bar represents: the approximate time duration for when amphibian eggs and larvae 

may be present, when eggs and adult fairy shrimp may be found, and when amphibian metamorphosis may 

occur. 

* References include Bishop (1941), Green and Pauley (1987), Tyning (1990), Petranka (1998), Hulse et al. (2001), Smith 

(2001), Schwartz and Golden (2002), and White and White (2002).
Section 3: Introduction to Seasonal Pool Fauna 21

3.3: Salamanders in Seasonal Pools

Salamanders are four-limbed amphibians with 

long tails and smooth skin that live in moist or 

wet environments to avoid desiccation. In midAtlantic seasonal pools, there are seven species 

of salamanders that are indicators (Fig. 3-1, 3-2). 

These salamanders are in the mole salamander 

family, Ambystomatidae. The mole salamander 

family derives its common name from the terrestrial 

behavior of adults, who spend much of their 

lifetimes underground, often in shrew or other 

small mammal burrows, or beneath debris. These 

salamanders emerge above ground primarily during 

the breeding season when they migrate to and breed 

in seasonal pools. Mole salamanders tend to be 

very faithful to their breeding sites, often returning 

each year (although individuals may skip years) to 

the same pools following the same migration paths 

(Box 2-3; Shoop, 1968; Stenhouse, 1985; Scott, 1994; 

Windmiller, 1996). 

On land, adult salamanders play important roles 

in forest ecology as major predators of forest fl oor 

arthropods and as prey to reptiles, birds, and 

mammals (Windmiller, 1996). In seasonal pools, 

smaller-sized ambystomatid salamander larvae 

are a food source for backswimmers, predaceous 

diving beetles, and other predators; larger-sized 

(later-development stage) larvae may function as 

top predators of aquatic invertebrates and other 

developing amphibians, including conspecifi cs. 

Salamanders may exert a controlling effect on 

mosquito populations; mosquito larvae density 

was 98% lower in wetlands with ambystomatid 

salamanders compared to wetlands with no 

salamanders (Brodman et al., 2003). 

Ambystomatid salamanders have internal 

fertilization with a sperm transfer mechanism 

using spermatophores (Plate 3-1). Males deposit 

spermatophores (sperm capsules atop conical 

gelatinous bases) on pool bottoms, vegetation, rocks, 

or land. Males court individually or in groups, 

known as congresses, by performing underwater 

courtship dances for the females (Tyning, 1990). 

Plate 3-1. Spermatophores of spotted salamanders. (A) A spermatophore is shown next to an underwater 

salamander and (B) in close-up on a leaf. (C) Males deposit dozens of spermatophores on fl oors of pools.

A

B

C

Photos: (A, B) Michael Male, (C) Steven M. Roble
22 An Introduction to Mid-Atlantic Seasonal Pools

Plate 3-2. Egg mass, larva, and adult salamander. (A) A spotted salamander egg mass, (B) bluespotted salamander larva, and (C) eastern tiger salamander adult represent the various life stages of 

species of mole salamanders seasonal pools.

Courtship stimulates a female to position herself 

over the spermatophore and then pick up the sperm 

capsule in her cloaca where internal fertilization 

occurs (Pough et al., 2004). Females of some mole 

salamander species (e.g., spotted, eastern tiger) lay 

egg masses that are large and conspicuous (Plate 3-

2); others lay single eggs or short strands. 

Larvae develop in water and have wide heads, bushy 

external gills (three per side), and a long dorsal fi n 

that stretches from behind the head to the end of the 

tail (Plate 3-2). 

Ambystomatid salamanders are generally long-lived, 

with some surviving 20 years or longer. Males may 

be distinguished from females by their enlarged 

cloacal glands (noticeable bulges under the base of 

the tail) and more laterally compressed tails. In the 

breeding season, pregnant females can be identifi ed 

by their enlarged sausage-like bodies full of eggs. 

A

C

B

Photos: Steven M. Roble
Section 3: Introduction to Seasonal Pool Fauna 23

3.4: Frogs and Toads in Seasonal Pools

Plate 3-3. Egg masses, tadpoles, and adult frog. (A) Egg masses, (B) recently-hatched 

tadpoles, and (C) adult are the various life stages of the wood frog, a seasonal pool indicator 

species. The adult wood frog pictured is a male making vocalizations.

species may also feed on smaller-sized larvae or 

amphibian eggs. Tadpoles undergo a remarkable 

metamorphosis from herbivorous or omnivorous, 

aquatic tadpoles to carnivorous, terrestrial adults 

(Plate 3-3; Pough et al., 2004). 

In mid-Atlantic seasonal pools, there are two species 

of frogs that are indicators: the wood frog (Rana 

sylvatica) and the eastern spadefoot (Scaphiopus 

holbrookii). There are also many other facultative 

species of frogs and toads that use mid-Atlantic 

seasonal pools, among them: barking treefrog 

(Hyla gratiosa), gray treefrog (Hyla versicolor/Hyla 

chrysoscelis), upland chorus frog (Pseudacris feriarum 

feriarum), and spring peeper (Pseudacris crucifer 

crucifer) (see Field Guide, page 41).

A B

C

Frogs are four-limbed, tailless amphibians. 

Vocalizations, identifi able calls made primarily 

by adult male frogs, play important roles in frog 

behavior, including mating and defending territories 

(Plate 3-3). Seasonal pool-breeding frogs have 

external fertilization, with males releasing their 

sperm onto eggs as they are deposited by females. 

Many male frogs clasp their female partners from 

behind while mating (a behavior called amplexus) to 

ensure that their sperm fertilizes the females’ eggs. 

Frog egg masses are less cohesive than the egg masses 

of most mole salamander species (Plate 3-3).

Eggs laid in the water hatch into aquatic larvae 

(tadpoles) (Plate 3-3), which are primarily 

suspension feeders; however, tadpoles of some 

Photos: (A) Tim Maret, (B, C) Steven M. Roble
24 An Introduction to Mid-Atlantic Seasonal Pools

3.5: Reptiles, Birds, and Mammals

in Seasonal Pools

There are many species of reptiles, birds, and 

mammals in the mid-Atlantic region that feed on 

prey in or near seasonal pools. Freshwater turtles 

visit seasonal pools in the spring or summer to 

feed on algae, terrestrial and aquatic plants, and 

invertebrates; several species also feed on amphibian 

eggs, larvae, and adults. Freshwater turtles may be 

observed in seasonal pools basking out of water on 

emergent vegetation or logs during warm weather. 

Spotted turtles (Clemmys guttata) inhabit shallow, 

soft-bottomed freshwater habitats with aquatic 

vegetation that are in close proximity to woodlands 

(Plate 3-4). Spotted turtles feed in seasonal pools 

extensively in the early spring; individuals have 

been known to spend up to three to four months in 

seasonal pools (Mitchell, 1994; Milam and Melvin, 

2001). Other turtle species that visit seasonal pools 

in the mid-Atlantic region include eastern snapping 

Plate 3-4. Turtles of seasonal pools. (A) Eastern box turtles may aestivate in the mud of seasonal pools 

during hot weather. (B) Spotted turtles visit seasonal pools to feed on invertebrates, amphibian eggs, and other 

food items.

turtles (Chelydra serpentina serpentina), eastern mud 

turtles (Kinosternon subrubrum subrubrum), eastern 

box turtles (Terrapene carolina) (Plate 3-4), and 

painted turtles (Chrysemys picta) (Ernst et al., 1994).

Snakes that have aquatic or semi-aquatic life 

histories may be observed hunting in seasonal pools. 

More terrestrial snakes may also visit seasonal 

pools to drink water or to feed, particularly when 

amphibian larvae are concentrated in shallow pools 

(J.C. Mitchell, pers. comm.). Snake species that visit 

seasonal pools to feed primarily on amphibians 

include, among others, northern watersnakes 

(Nerodia sipedon sipedon), eastern gartersnakes 

(Thamnophis sirtalis sirtalis), and eastern 

ribbonsnakes (Thamnophis sauritus) (Ernst and 

Barbour, 1989; Mitchell, 1994; Windmiller, 1996). 

A B

Photos: Steven M. Roble
Section 3: Introduction to Seasonal Pool Fauna 25

Plate 3-5. Deer in an open-canopy seasonal pool. 

White-tailed deer visit seasonal pools to drink water and 

to forage on vegetation growing in and around the pool 

basin.

Birds also prey on animals in or near seasonal pools. 

Wading birds, such as great blue herons (Ardea 

herodias) (Roble and Stevenson, 1998), waterfowl, 

such as wood ducks (Aix sponsa), and woodland 

birds visit the pools to feed on insect and amphibian 

larvae. At coastal plain seasonal pools, yellow 

legs (Tringa melanoleuca, Tringa fl avipes), little 

blue herons (Egretta caerulea), and green herons 

(Butorides virescens) feed on amphibian larvae 

(Hassinger et al., 1970). Owls prey on amphibians 

migrating to and from seasonal pools; birds of prey, 

such as red-shouldered hawks, feed on seasonal pool 

animals. 

Seasonal pools also serve as important sources of 

water and food for many mammals in the midAtlantic region. Deer drink water and forage on 

aquatic vegetation in seasonal pools (Plate 3-5). 

Raccoons feed on amphibian larvae and adults, large 

insects, and other inhabitants of seasonal pools 

(Seale, 1982; Kenney and Burne, 2001). Shrews visit 

seasonal pools to forage on insects (Winfi eld et al., 

1981; Brooks and Doyle, 2001). Bats visit seasonal 

pools to drink water and to feed on fl ying insect 

prey (Biebighauser, 2002). Scavenging carnivorous 

mammals are likely to feed on animals trapped, 

dying, or desiccated in the shallow drying or dried 

beds of seasonal pools (Winfi eld et al., 1981), 

including red fox, striped skunk, gray fox, bear, and 

opossums. 

Photo: Tim Maret
26 An Introduction to Mid-Atlantic Seasonal Pools

3.6: Invertebrates in Seasonal Pools

Seasonal pools provide habitat to a wide variety of 

invertebrate species. Invertebrates in seasonal pools 

play important ecological roles, as a food source to 

amphibians and other invertebrates, as consumers 

of detritus, and as predators of smaller-sized 

amphibian larvae and invertebrates. 

Fairy shrimp, crustaceans in the Order Anostraca, 

are an indicator group found in mid-Atlantic 

seasonal pools. Fairy shrimp do not have defenses 

against predators; therefore, they are very rarely 

reported in pools with predatory fi sh and are found 

in lower abundances in pools with predatory insects. 

Adults appear in pools in late winter or early spring 

before predatory insects reach maximum densities 

(Wiggins et al., 1980). Five species of fairy shrimp 

may occur in pools in the mid-Atlantic region, 

although their distribution is not well known (Field 

Guide; Belk, 1975; Belk et al., 1998). Fairy shrimp 

glide upside-down and fi lter-feed microbes and 

detritus from the water column or substrate (Plate 3-

6; Smith, 2001). Fairy shrimp produce eggs that can 

survive the drying and freezing of pool sediments; 

they may remain viable for many years before 

fi nally hatching. Adult fairy shrimp have patchy 

and unpredictable presence and abundance in pools 

across the landscape. There is very little published 

research on these animals in the mid-Atlantic 

region. 

In addition to the indicator fairy shrimp, there are 

numerous facultative invertebrates found in or on 

the surface of seasonal pools. The more distinctive 

facultative classes and orders are included in the 

Field Guide; the following is an incomplete list 

of classes found in the seasonal pool invertebrate 

community with the common names of some of 

their members. Crustaceans include the classes 

Branchiopoda (clam shrimp and cladocera), 

Ostracoda (seed shrimp), Malacostraca (isopod and 

amphipod), and Copepoda (copepod). Molluscs 

include the classes Gastropoda (amphibious snail) 

and Pelecypoda (fi ngernail clam). Arthropods 

include the classes Insecta (predaceous diving beetle, 

caddisfl y larva, phantom midge larva, chironomid 

midge larva, and mosquito larva) and Hydrachnidia 

(water mite). Annelids include the classes Hirudinae 

(leech) and Oligochaeta (aquatic oligochaete worm). 

Plate 3-6. Fairy shrimp in seasonal pools. Seasonal pools may contain the indicator group of 

crustaceans, the fairy shrimp. In pools where they occur, they may be abundant in the late winter or 

early spring; notice the eleven pairs of swimming legs. 

Photo: Steven M. Roble
4

Section 4: Conservation Challenges Facing Seasonal Pools 27

Habitat loss and alteration associated with land 

development present the greatest challenges to the 

existence and health of seasonal pool ecosystems 

in the mid-Atlantic region. Seasonal pools, and 

the wildlife they support, are threatened by direct 

loss (e.g., through fi lling or draining), as well as by 

practices that degrade the pool: terrestrial habitat 

loss and fragmentation, biological introductions and 

removals, mosquito control practices, amphibian 

diseases, atmospheric deposition, and climate 

change.

 

4.1: Direct Loss of Seasonal Pools

The direct loss of seasonal pools due to draining, 

fi lling, and dredging in association with human 

activities presents a major threat to the persistence 

of seasonal pool-dependent biota. According to a 

U.S. Fish & Wildlife Service study, the following 

land development activities accounted for losses 

in freshwater wetlands in the time period between 

1986 and 1997: 30% of losses were due to urban 

development, 26% of losses were due to agriculture, 

23% of losses were due to silviculture, and 20% of 

losses were due to rural development (Dahl, 2000). 

Although seasonal pools, because of their small sizes 

and impermanent waters, were largely not accounted 

for in these statistics, it is likely that they are being 

lost in a similar manner. 

Destruction of individual seasonal pools will 

eliminate populations of permanent residents, such 

as fairy shrimp, at those pools (Colburn, 2004). Also 

at risk are migratory residents of seasonal pools. 

Because of their limited dispersal abilities and site 

fi delity to breeding pools (Berven and Grudzien, 

1990; Scott, 1994), adult pool-breeding amphibians 

are unlikely to make use of other pools in lieu of 

lost pools. In fact, adult amphibians may continue 

to return to the site of former (destroyed) pools 

throughout their lifetimes, rather than seeking out 

new breeding pools. 

The loss of a seasonal pool may negatively impact 

other seasonal pool communities in the surrounding 

area. As seasonal pools and other wetlands become 

fewer in number, the distances between pools 

become greater, eventually exceeding the dispersal 

abilities of amphibians and reptiles (Gibbs, 1993; 

Semlitsch and Bodie, 1998; Gibbs, 2000). When 

seasonal pools are destroyed, the number of 

individuals that would have potentially dispersed 

to other pools is reduced (Gibbs, 1993; Semlitsch 

and Bodie, 1998), thus decreasing the rate of genetic 

exchange among populations and potentially 

inhibiting the rescue of locally declining or extinct 

populations (Laan and Verboom, 1990; Marsh and 

Trenham, 2001). For larger-bodied species that visit 

pools for food (e.g., waterfowl), these increased 

travel distances between pools may have important 

energetic implications (Gibbs, 2000). 

4.2: Terrestrial Habitat Loss and 

Fragmentation

Urbanization, intensifi cation of agriculture, 

increased density of roads, and timber harvesting 

have caused massive transformations of the 

landscape in the eastern United States. Changes 

in land-use in the mid-Atlantic region and their 

consequences for wildlife habitat, landscape 

connectivity (the extent to which the landscape 

facilitates wildlife movement), and hydrology present 

the largest challenges to seasonal pool conservation 

(Plate 4-1).

CONSERVATION CHALLENGES FACING SEASONAL POOLS

Plate 4-1. Aerial view of landscape fragmentation. 

This color infrared aerial photograph shows a seasonal 

pool (dark circle marked by arrow) surrounded by 

human development.

Photo: Massachusetts Department of Environmental Protection
28 An Introduction to Mid-Atlantic Seasonal Pools

Biological Effects of Habitat Loss and 

Fragmentation

Many of the wildlife species that use seasonal 

pools for breeding and feeding spend the majority 

of their lives in the forests and grasslands that 

are being lost to increasing human development. 

Thus, the conversion of terrestrial habitat directly 

threatens many members of the biological 

communities of seasonal pools by taking away 

their sustaining environment.

Land conversion also indirectly affects seasonal 

pool biological communities by restricting 

wildlife movements and facilitating invasion 

by disturbance-tolerant organisms. Land-use 

changes translate into fragmentation of the 

landscape, as forest patch to forest patch and 

forest patch to seasonal pool distances increase 

and the pathways of travel become more diffi cult 

for animals to traverse (Plate 4-1). 

The conversion of natural habitats (forests and 

grasslands) to open land-uses, such as lawns, 

agricultural lands, and impervious surfaces (i.e., 

any surface that prevents water from infi ltration 

into the soil, such as roads, buildings, and parking 

lots) creates barriers to movement and decreases 

landscape connectivity (Plate 4-2; Forman et 

al., 2003). Amphibians have diffi culty traversing 

open landscapes due to higher temperatures and 

lower soil moisture (deMaynadier and Hunter, 

1999; Rothermel and Semlitsch, 2002; Rothermel, 

2004). Studies have documented pool-breeding 

amphibians’ preference for forested habitat in the 

eastern United States. Spotted salamanders and 

wood frogs favor forests and avoid open-canopy 

habitats in their migrations (Semlitsch, 1981; 

Raymond and Hardy, 1991; Petranka et al., 1994; 

deMaynadier and Hunter, 1999; Rothermel and 

Semlitsch, 2002; Faccio, 2003). Mature forests 

provide moist microhabitats for amphibians: 

the thick leaf litter traps and stores moisture, 

the coarse woody debris provides cover and 

prevents soil drying, and a closed canopy with 

an understory offers shade and slows evaporation 

from the forest fl oor (Petranka et al., 1994). As 

juveniles and adults, pool-breeding amphibians 

are carnivorous, feeding on invertebrates such 

as earthworms, snails, slugs, spiders, crickets, 

beetles, and ants (Bishop, 1941; Petranka, 

1998). They fi nd this food in the leaf litter of 

forested areas beneath woody debris and below 

ground. Underground mammal burrows provide 

protection for mole salamanders from predators 

and freezing temperatures (Madison, 1997; 

Regosin et al., 2003a). Destruction or degradation 

of forested habitat as a result of poor forestry and 

land development practices negatively impact 

amphibian populations (Windmiller et al., 2006).

Plate 4-2. Terrestrial habitat fragmentation. 

Conversion of land near seasonal pools for (A) 

residential development, (B) golf courses, and other land 

uses will impact the faunal populations of these pools.

A

B

Photos: Bryan Windmiller
Section 4: Conservation Challenges Facing Seasonal Pools 29

Fragmentation of the terrestrial landscape 

inhibits migrations of amphibians between the 

terrestrial habitat (where they spend greater 

than 90% of their juvenile and adult lives) and 

their breeding pools (Laan and Verboom, 1990; 

deMaynadier and Hunter, 1999; Rothermel and 

Semlitsch, 2002; Rothermel, 2004), decreasing or 

arresting their reproductive success. Decreased 

landscape connectivity may impede the dispersal 

of individuals between ponds, reducing rates of 

genetic exchange and potentially increasing the 

risk of local extinctions (Reh and Seitz, 1990; 

Laan and Verboom, 1990; Marsh and Trenham, 

2001). 

Roads, a pervasive and ever-increasing feature 

of the human-altered landscape, affect the 

survival and health of seasonal pool-dependent 

wildlife populations and the persistence of 

seasonal pools. Roads are a major source of 

fatalities (both directly as road kill and indirectly 

due to increased vulnerability to predators) 

and present a formidable physical barrier to 

animal migrations (Gibbs and Shriver, 2005). 

Amphibians and reptiles that try to cross roads 

experience high traffi c mortality, particularly 

during the mass seasonal migrations of frogs and 

salamanders in early spring. Traffi c mortality 

may cause signifi cant declines in amphibian 

populations (Plate 4-3; Fahrig et al., 1995; Gibbs 

and Shriver, 2005). Amphibians’ small body size 

makes overcoming man-made obstacles such 

as levees, ditches, and curbed roads a slow and 

diffi cult venture (Gibbs, 1998). Their small size 

and slow speed also makes them very vulnerable 

to predation when they are physically exposed 

due to the human-altered landscape (Gibbs, 1998; 

Rothermel, 2004). 

The loss of reproductively-mature amphibians 

killed en route to breeding pools will have a 

signifi cant impact on the population due to the 

additional loss of all of their potential future 

offspring (Dodd and Smith, 2003). The negative 

ecological effects of road construction on wetland 

biodiversity are cumulative over time (Findlay 

and Bourdages, 2000). The loss of amphibian and 

reptile species as a result of road construction may 

take an average of eight years to detect, and the 

full effects may not become apparent for decades 

(Findlay and Bourdages, 2000). When a threshold 

of road mortality has been crossed, populations 

may go into rapid decline and eventually become 

locally extinct (Gibbs and Shriver, 2005). 

Watershed and ecological impacts of roads on 

seasonal pools, such as altered wetland hydrology, 

road salt pollution, and reduced amphibian 

habitat and movement, may extend 984 ft (300 

m) or more in each direction from a road edge 

(Forman and Deblinger, 2000). For example, 

the presence of tiger salamanders is negatively 

associated with the cumulative length of paved 

roads within 3281 ft (1 km) of their breeding 

pools (Porej et al., 2004).

The extent and pattern of terrestrial habitat 

degradation and loss that seasonal pooldependent animals can tolerate without 

experiencing population declines and local 

extinctions depends upon the characteristics of 

the species and local conditions (Fahrig, 2002; 

Homan et al., 2004). Amount of forest cover, 

length and density of roads, and the degree of 

wetland isolation (distance to nearest wetland 

neighbor) have been shown to be among the 

most important predictors of amphibian species 

richness (Lehtinen et al., 1999; Porej et al., 2004; 

Herrmann et al., 2005). 

Plate 4-3. Spotted salamander roadkill. Particularly 

where roads separate seasonal pools from their 

terrestrial habitat, road mortality is a serious threat to 

amphibian populations.

Photos: James P. Gibbs
30 An Introduction to Mid-Atlantic Seasonal Pools

Physical Effects of Habitat Loss and 

Fragmentation

Land transformations in seasonal pools’ 

watersheds may directly affect the physical 

properties of seasonal pools in a variety of ways. 

These may include altered water chemistry, 

altered water regime (decreased or increased 

hydroperiods and higher or lower water levels), 

temporal variation in hydrology, altered water 

temperature, and increased sedimentation or 

erosion. Physical impacts to the seasonal pool due 

to land-use change, in turn, affect the biological 

community. Land-use practices in the watershed 

may alter the distribution of pool hydroperiods, 

either by a change in the amount and timing of 

water inputs to the pool or a change in the canopy 

cover. Surface water run-off to pools in impacted 

watersheds will have elevated temperatures due 

to the elimination of overhanging canopy and 

the path of water fl ow along heated impervious 

surfaces (Schueler, 1994). 

Roads act as conduits for pollution, channeling 

fast-moving run-off that can contain car byproducts, road salts, sediments, lawn applications, 

and other chemicals (Jones et al., 1992; Jones 

and Sroka, 1997). Increasing impervious surface 

area in a watershed potentially adds to the 

amount of non-point source pollution entering 

freshwater systems, including nutrients and 

chemicals (Wernick et al., 1998; Sonoda et al., 

2001). Roadside seasonal pools have higher 

specifi c conductance and higher sodium and 

chloride levels compared to woodland seasonal 

pools away from roads (Turtle, 2000). Land cover 

change can also modify the quantity and type 

of sediment input into freshwater bodies (Jones 

et al., 2001). Pollution may affect seasonal pools 

disproportionately more than other aquatic 

habitats, such as rivers and lakes, because of the 

pools’ small size and isolation from other water 

bodies. In late spring and summer, evaporation 

may result in very high concentrations of ions 

or toxins in the remaining seasonal pool water. 

Also, seasonal pools are fi lled partially or entirely 

by precipitation, runoff, and snowmelt that 

have undergone little to no buffering by the 

soil (Gascon and Planas, 1986; Wyman, 1990; 

Whigham and Jordan, 2003). Thus local events 

(such as nearby house or road construction) 

may have a great impact on the pools’ water 

quality. Chemicals in the watershed, including 

pesticides from agricultural, residential, and 

industrial activities, may alter food web dynamics 

and decrease populations of invertebrates or 

amphibians (Boone and Bridges, 2003). Proximity 

to human development also increases the risk of 

pollution of pools by illegal dumping (Plate 4-4).

Plate 4-4. Garbage fi lls this seasonal pool. This pool 

in southern Virginia has been used as a trash dumping 

site.

Photo: Michael S. Hayslett
Section 4: Conservation Challenges Facing Seasonal Pools 31

4.3: Other Conservation Challenges

Biological Introductions and Removals

Seasonal pools may be dredged or impounded 

for conversion to permanent water, for use as 

farm ponds or stock tanks. Once the hydrology 

is altered from seasonal to permanent, predators 

such as bullfrogs and fi sh may invade the pool 

and increase predation pressure on seasonal 

pool-dependent animals. Purposeful introductions of fi sh to seasonal pools for recreational 

fi shing and/or mosquito control may also occur, 

which will likely have negative impacts on 

indigenous species of amphibians (Thompson 

et al., 1980; Hecnar and M’Closkey, 1997; 

Kiesecker, 2003; Colburn, 2004). For example, 

bluegill sunfi sh (Lepomis macrochirus) stocked in 

a Shenandoah Valley sinkhole pond may be responsible for declines in eastern tiger salamander 

populations (Buhlmann et al., 1999; Buhlmann 

and Mitchell, 2000). 

Seasonal pool-dependent amphibians are 

collected as adults for consumption or laboratory 

use, or as larvae for use as fi shing bait. According 

to a survey of fourteen scientifi c products 

suppliers, nine suppliers offer species of mole 

salamanders for sale for educational purposes 

(Jensen and Camp, 2003). The majority of 

these animals are likely captured in or around 

wetlands and seasonal pools, rather than being 

captive-bred (Jensen and Camp, 2003). Eastern 

tiger salamander larvae are sold in baitshops 

as “water dogs” (Jensen and Camp, 2003). The 

cumulative impact of collection of seasonal pooldependent fauna is unknown in the mid-Atlantic 

region. 

Mosquito Control Practices

Mosquito control practices may target seasonal 

pools. The most damaging practice employed 

for mosquito control is the fi lling or draining of 

seasonal pools. Other mosquito control methods 

include the application of surface fi lms (oils 

added to ponded waters to suffocate mosquito 

larvae), chemical larvicides, and biological 

control agents. The effects of these mosquito 

control practices on seasonal pool food webs and 

pool-breeding amphibian eggs, larvae, and adults 

have not been extensively studied (Colburn, 

2004). However, it is known that these control 

methods may impact groups of animals other 

than mosquito larvae and negative effects may 

take two years or longer to observe (Templeton 

and Laufer, 1983; Hershey et al., 1998). Control 

agents that reduce population sizes of plankton 

and invertebrates may, in turn, affect poolbreeding amphibians by reducing their food 

supply (Boone and Bridges, 2003). Additionally, 

the interaction of mosquito control techniques 

with other anthropogenic stressors may 

negatively impact the seasonal pool community 

(Boone and Bridges, 2003).

Amphibian Diseases

Another threat posed to seasonal pool-dependent 

amphibians is disease. Recent mortality events 

and increased susceptibility to diseases may be 

partially the result of reduced immune function 

from increased stress associated with habitat 

degradation (Blaustein and Kiesecker, 2002). 

Chytrid fungus (Batrachochytrium dentrobatidis) 

and ranaviruses can cause mass mortality in 

amphibian larvae, metamorphosing individuals, 

juveniles, and adults. These diseases may be 

transported by fi eld equipment, fi shing gear, 

or introduction of invasive species (Semlitsch, 

2000; Carey et al., 2003). Ichthyophonus fungus 

and ranavirus infections have caused deaths of 

wood frog larvae and recently metamorphosed 

individuals, and ranavirus has caused deaths 

of spotted salamander larvae in seasonal pools 

in the mid-Atlantic region (D.E. Green, pers. 

comm.). For fi eld work practices that minimize 

the spread of these diseases, refer to Appendix B.

Atmospheric Deposition

Atmospheric deposition may impact the water 

chemistry of seasonal pools to a greater extent 

than other aquatic habitats because many 

pools are primarily fi lled by precipitation and 
32 An Introduction to Mid-Atlantic Seasonal Pools

surface run-off (Gascon and Planas, 1986; 

Wyman, 1990). Acidifi cation of pools through 

acid deposition does not have straightforward 

impacts on pool biological communities and 

may differ according to characteristics of the 

pool. Some studies show negative impacts of 

low pH on amphibian reproductive success (e.g., 

Pough, 1976; Gascon and Planas, 1986; Sadinski 

and Dunson, 1992) whereas others show no 

measurable impacts (e.g., Cook, 1983; Albers and 

Prouty, 1987). However, acidifi cation elevates and 

makes more soluble and hence more bioavailable 

concentrations of metals in seasonal pool waters. 

High levels of metals, such as aluminum, copper, 

iron, lead, silicon, and zinc, may reduce hatching 

success of amphibian eggs, reduce larval survival, 

and increase the prevalence of amphibian 

deformities (Albers and Prouty, 1987; Blem 

and Blem, 1989, 1991; Rowe and Dunson, 1993; 

Horne and Dunson, 1995; Jung and Jagoe, 1995). 

Acid precipitation and atmospheric deposition 

of metals from industrial and residential sources 

may act synergistically to affect seasonal pool 

communities.

Climate Change

Seasonal pools face uncertain impacts from 

the climate change projected to occur over 

the next century. In the mid-Atlantic region, 

air temperatures and average precipitation are 

projected to increase; however, precipitation 

events are predicted to be of higher intensity 

and more erratic in timing (U.S. EPA, 2001). 

These precipitation and temperature patterns 

have implications for hydroperiods and water 

temperatures of seasonal pools, which will, in 

turn, affect amphibian egg and larval survival 

(Brooks, 2004). Climate changes may also 

affect the seasonal timing of animal activity. 

There is evidence to suggest that the warming 

of the climate over the last century has affected 

the breeding patterns of amphibians in the 

northeastern United States (Gibbs and Breisch, 

2001).
5

Section 5: Future Directions 33

FUTURE DIRECTIONS: 

CONSERVATION OF SEASONAL POOLS IN THE MID-ATLANTIC REGION

5.1: Seasonal Pool Conservation in 

the Mid-Atlantic Region

As yet, there are few comprehensive efforts to include 

seasonal pools in natural resources management 

in most of the mid-Atlantic States. The New Jersey 

Division of Wildlife Endangered and Nongame 

Species Program initiated a Vernal Pool Survey 

Project in 2000, a statewide seasonal pool mapping 

program. This project’s goal is to locate, map, and 

inventory seasonal pools statewide and monitor their 

amphibian populations utilizing a trained group 

of volunteers (Tesauro, 2004). A similar project, 

the development of a web-based seasonal pool 

registry and research program, is being prepared 

for implementation in Pennsylvania by the Western 

Pennsylvania Conservancy (see Appendix C). 

In the other mid-Atlantic states, there have been 

smaller-scale initiatives undertaken by governmental 

agencies, nongovernmental organizations, and 

coalitions. For example, the ARMI-NE of the USGS 

and partners (U.S. Fish and Wildlife Service and 

National Park Service) have located, mapped, and 

surveyed amphibian populations at seasonal forest 

pools in nine National Parks and National Wildlife 

Refuges in the mid-Atlantic states (see Appendix C). 

Unique systems of seasonal pools in the midAtlantic region, such as sinkhole ponds in Virginia 

and Delmarva bays in Delaware-Maryland, have 

received attention by naturalists, academics, and 

agency scientists (e.g., Rawinski, 1997; Roble, 

1998; Buhlmann et al., 1999; Zankel and Olivero, 

1999). However, there is a considerable need for 

additional research on seasonal pools. Moreover, 

existing studies have largely not been translated into 

conservation or management programs.

Seasonal pools should be valued and managed as important ecosystems for support of biodiversity in the 

mid-Atlantic region. In recent years, concern over 

amphibian conservation has escalated due to reports 

of declines in amphibian populations on a globalscale (Barinaga, 1990; Stuart et al., 2004). Existing 

amphibian monitoring efforts, such as the National 

Wildlife Federation’s FrogWatch and the USGS 

North American Amphibian Monitoring Program, 

provide data on frog and toad populations but do 

not address the major cause of amphibian declines: 

the loss of habitat including seasonal pools. There is 

a need to bring a broader, landscape perspective to 

the conservation of amphibians in the mid-Atlantic 

region. There must be adequate protection and management of habitat, which for seasonal pool-breeding 

amphibians includes the seasonal pool basin and 

the surrounding terrestrial area that extends 1000 ft 

(305 m) or farther from the edge of the pool. Characteristics of the landscape up to 3281 ft (1000 m) 

from the pool edge, such as amount of forest cover 

or densities of roads, may also strongly infl uence the 

presence and densities of amphibian species (Homan 

et al., 2004; Porej et al., 2004; Herrmann et al., 

2005). For successful management of the seasonal 

pool ecosystem, the seasonal pool itself should not 

be considered separate from the terrestrial habitat. 

The authors recommend that a three-pronged 

approach be taken for conservation of seasonal 

pools in the mid-Atlantic region. Simultaneous 

efforts should be taken in the following areas: 

education and research, seasonal pool inventory, 

and landscape-level management. There needs to be 

a targeted campaign to raise the level of awareness 

and knowledge about seasonal pools, the reliance 

of amphibians upon seasonal pools, and the threats 

that face them. The audience of this campaign 

should be broad, and include professionals as well 

as the general public. It is also important to escalate 

seasonal pool research efforts in the mid-Atlantic 

region. Second, there needs to be a region-wide 

initiative to locate and inventory seasonal pools in 

order to determine their abundance, distribution, 

and biological resources. Lastly, seasonal pools and 

their associated life zones should be integrated into 

landscape-level planning by local, county, and state 

agencies and nongovernmental organizations. Pools 

should be prioritized for conservation considering 

several factors: the degree to which amphibians and 

invertebrates depend upon them, the condition of 

the terrestrial life zone, and the proximity to and 

density of seasonal pools in the landscape (e.g., pool 

clusters). 
34 An Introduction to Mid-Atlantic Seasonal Pools

5.2: Education and Research on 

Seasonal Pools

In order to facilitate successful seasonal pool 

conservation efforts, stakeholders must be identifi ed, 

information must be disseminated, and the issue 

has to be publicized. In addition, basic research on 

seasonal pools in the mid-Atlantic region is needed 

so as to inform effi cacious management strategies.

Establish a Scientifi c and Management 

Dialogue. Regardless of whether there 

have been local or state efforts at seasonal 

pool inventory or conservation, there are 

individuals in each mid-Atlantic state who 

are working with seasonal pool-related issues. 

For example, there are nongovernmental 

organizations working on amphibian 

conservation research and policy, academics 

and governmental agencies studying 

amphibian populations, and naturalists 

hosting educational programs in local 

parks. These interested individuals should 

be brought together. Workshops can be held 

on locating seasonal pools using various 

tools such as aerial photography and fi eld 

verifi cation, or a mid-Atlantic seasonal 

pools conference can be convened with the 

participation of experts from states that have 

seasonal pool programs in place, such as New 

Jersey, Maine, and Massachusetts. 

Increase Public Awareness. The level 

of public awareness is very low. Amphibians, 

such as spotted salamanders and wood frogs, 

will likely be of greatest interest to the general 

citizenry. The connection between seasonal 

pools and these charismatic amphibians must 

be made. The target audience should be broad 

and include homeowners, school children, 

and volunteers. 

Raise Level of Knowledge. Many of the 

studies on seasonal pools referred to in this 

publication were carried out in areas other 

than the mid-Atlantic region, particularly in 

Maine, Massachusetts, and South Carolina. 

More studies on the natural history, ecology, 

hydrology, vegetation, and conservation 

biology of seasonal pool ecosystems are 

needed in the mid-Atlantic region. Research 

partnerships should be explored between 

academic institutions and governmental 

agencies. 

5.3: Inventory of Seasonal Pools

An important requirement for sustainable 

management of a resource is an inventory of its 

distribution and status. Currently, the number of 

seasonal pools, their distribution in the landscape, 

and their biological resources are unknown in the 

mid-Atlantic region, although efforts are underway 

in New Jersey and are beginning in Pennsylvania. 

Locate and Inventory Seasonal Pools. 

Seasonal pools in the mid-Atlantic region 

need to be located and mapped with the data 

assembled electronically and in GIS format 

and fauna and fl ora must be inventoried. 

This may best be carried out at the countyor state-level through volunteer programs, 

similar to the New Jersey’s Vernal Pool 

Survey Project. Another approach would 

be standardizing and housing information 

on seasonal pools and their fauna in a 

federal program, similar to the way the 

North American Breeding Bird Survey is 

administered (see http://www.pwrc.usgs.gov/

bbs). (For techniques to locate seasonal pools 

refer to Appendix A. For general information on 

documenting seasonal pools refer to Appendix 

B. For existing seasonal pool programs, 

including New Jersey, refer to Appendix C.) 

Monitor Seasonal Pools. Once 

seasonal pools are identifi ed, they should 

be monitored. The rigor and method of 

monitoring will differ according to the agent 

undertaking the monitoring and the purpose 

of the effort. For most seasonal pool efforts, 

documenting the use of the pool by indicator 

species (e.g., presence of spotted salamander 

egg masses) may be suffi cient. In other cases, 
Section 5: Future Directions 35

more extensive population studies may be 

carried out. Long-term, repeated sampling 

of a subset of seasonal pools throughout the 

mid-Atlantic region is essential to catalogue 

the biodiversity and ecosystem health of 

the pools and to determine amphibian 

population trends. Herpetofauna that use 

seasonal pools may take years or longer to 

document and invertebrate communities 

may undergo rapid shifts throughout the year 

and between years (Mahoney et al., 1990; 

Pechmann et al., 1991; Gibbons et al., 1997; 

Simovich, 1998). Additionally, it is important 

to record spatial and temporal changes in 

seasonal pool communities and other biotic 

and abiotic parameters in order to understand 

and forecast responses of seasonal pool 

communities to climate change, land-use 

change, and other stressors.

5.4: Landscape-Level Planning and 

Management

Successful seasonal pool conservation can only 

occur when integrated into landscape-level planning. 

All conservation plans must take into account the 

three life zones described in Section 2. However, 

in order to adequately protect the seasonal pool 

biological community, seasonal pools require 

customized, landscape-level approaches.

Acquisition and Protection of Intact 

Habitats. Although every pool may have 

value, nonregulatory natural resource 

conservation tools such as acquisition and 

conservation easements should initially target 

seasonal pools that are particularly valuable 

in terms of biodiversity support. Efforts 

should be especially directed at protection 

of contiguous tracts of forested terrestrial 

habitat containing multiple seasonal pools. 

Protection of clusters of pools with a range of 

hydroperiods will provide the best probability 

of long-term success in supporting indicator 

species (Semlitsch, 2000). 

Develop Best Management Practices. 

Although protection of existing pools is the 

highest priority for seasonal pool conservation 

efforts, an active management approach 

should also be taken to protect populations of 

seasonal pool-breeding animals (Semlitsch, 

2000). Best management practices (BMPs) 

should be developed for pools with the input 

of scientists and resource managers. For 

example, management programs may include 

the elimination of invasive fi sh species, the 

control of sediment from development, 

or prescribed burns (e.g., Tyndall, 2001). 

Restoring or creating seasonal pools in 

strategic locations may also be an effective 

component of a management program 

(Biebighauser, 2000), although designing 

pools to have a specifi c hydroperiod and/or 

support a particular community of organisms 

may be diffi cult (Pechmann et al., 2001; 

Lichko and Calhoun, 2003). 

Create Best Development Practices. 

Best development practices (BDPs) that focus 

on lands surrounding seasonal pools need 

to be established with the participation of 

resource managers, state agencies, scientists, 

private businesses, and land developers. 

Recommendations should be outlined for 

more sustainable development and forestry 

practices based on the best available science. 

BDPs for residential and commercial 

development and forest habitat management 

guidelines to protect seasonal pools have 

already been developed for the northeastern 

United States (Calhoun and Klemens, 2002; 

Calhoun and deMaynadier, 2004). These 

publications may be a useful tool, but BDPs 

should also be formulated for the midAtlantic region. BDPs will likely be different 

for the mid-Atlantic region due to differences 

in ecology, regulatory infrastructure, and 

demographics as compared to New England. 

Also, the process of developing BDPs with 

the participation of all stakeholders is an 

important consensus-building activity that 

will greatly improve the chances of successful 

implementation (Preisser et al., 2000). 
36 An Introduction to Mid-Atlantic Seasonal Pools

Improve Transportation Planning. 

Roads can be planned and designed to reduce 

impacts on seasonal pools and their fauna. 

Road construction that destroys seasonal 

pools, occurs near seasonal pools, cuts 

through the terrestrial habitat surrounding 

seasonal pools, or separates pools from one 

another should be prevented. If roads must 

be built through terrestrial habitat or near 

seasonal pools, road overpasses can be built 

to allow biological and hydrological fl ows 

to remain uninterrupted. Where this is not 

possible, amphibian tunnels and other wildlife 

underpasses in conjunction with barriers 

can be constructed beneath roads to allow 

migrations (Fahrig et al., 1995; Forman and 

Alexander, 1998). Further research is needed 

to design animal tunnels/underpasses so 

that road mortality is reduced and landscape 

connectivity is restored in the most effective 

manner (Forman and Alexander, 1998; Dodd 

and Smith, 2003). If these design features 

cannot be installed, then road closures and 

assisted amphibian crossings can be organized 

to lower mortalities during major breeding 

events. 

Employ Regulatory Tools. Seasonal 

pools that qualify as “waters of the U.S.” are 

under federal jurisdiction, which regulates the 

disposal of dredge or fi ll material through a 

permitting program (Section 404 of the Clean 

Water Act). For the majority of seasonal pools, 

which do not fall under federal protection, 

alternative regulatory tools may be used in 

order to secure greater levels of protection. 

State and local wetland and forest regulations 

may be strengthened to protect seasonal 

pools and their surrounding terrestrial 

habitat. Seasonal pools may be identifi ed as 

important wildlife habitat in comprehensive 

land use plans (community master plans) or 

overlay zones may be designed by the local 

government and concerned stakeholders to 

protect seasonal pools. The resource overlay 

zones establish additional standards for 

development projects on top of the underlying 

zoning. These new zoning plans can be a 

mixture of regulations and incentives to 

conserve seasonal pools and their terrestrial 

habitats (Nolon, 1998; Calhoun and Klemens, 

2002). Voluntary stewardship programs may 

be initiated whereby landowners conserve 

their pools and follow best management/

development practices in adjacent forest areas 

and receive tax credits or annual subsidies in 

return (similar to the U.S. Fish and Wildlife 

Service’s Partners for Fish and Wildlife, see 

http://northeast.fws.gov/partners) (Tiner, 

2003a).
Field Guide to Seasonal Pool Fauna 37

Contents

Members of the Seasonal Pool Community ..................................................37

Field Guide 1: Salamanders of seasonal pools in the mid-Atlantic region ........................38

Field Guide 2: Frogs and toads of seasonal pools in the mid-Atlantic region ...................41

Field Guide 3: Invertebrates of seasonal pools in the mid-Atlantic region .......................46

In-Depth Information on Seasonal Pool Indicator Species .........................49

Mole salamanders ......................................................................................................................49

Frogs .............................................................................................................................................57

Fairy shrimp ...............................................................................................................................60

Comparison of Eggs and Larvae of Amphibian Indicator Species ..............62

Field Guide 4: Amphibian eggs in mid-Atlantic seasonal pools .........................................63

Field Guide 5: Amphibian larvae in mid-Atlantic seasonal pools ......................................66

FIELD GUIDE TO SEASONAL POOL FAUNA

The Field Guide is provided to help interested people identify members 

of the seasonal pool biological community. Pictorial fi eld guides are 

included to aid the identifi cation of adults, larvae, and eggs. For 

those who wish to learn more about the natural history (physical 

characteristics, behavior, phenology, and reproductive biology) of these 

indicator species, in-depth information is also provided. Before exploring 

seasonal pools, please refer to Appendix B for practices to prevent 

negative impacts to pool animals (p. 74).
38 An Introduction to Mid-Atlantic Seasonal Pools

* General information is derived from Bishop (1941) and Petranka (1998). Salamander lengths represent total length of the body and tail. 

Lengths are primarily from Conant and Collins (1998) and represent the range of average total lengths of these salamanders; where mid-Atlantic 

literature provided dissimilar total lengths, the widest range of lengths was selected. Distribution maps are adapted from the ARMI National 

Atlas for Amphibian Distributions (http://www.pwrc.usgs.gov/armiatlas/). Maps may not accurately refl ect the current presence of species in 

counties (see website for more information).

4.4 – 7.8 inches 

(11 – 20 cm)

Bright yellow to 

orange spots on 

black to bluishblack body

Habitat includes deciduous, mixed deciduous-coniferous, 

and coniferous forests; breeds in seasonal pools

Protected: Del., N.J., Va.

Description: p. 49

3.5 – 4.3 inches

(9 – 11 cm) 

Silvery-white or 

gray markings or 

bands on black body 

Habitat includes deciduous, mixed deciduous-coniferous, 

and coniferous forests; breeds in seasonal pool beds 

Protected: Del., N.J., Va.

Description: p. 50

7 – 8.3 inches

(17 – 21 cm)

Yellowish markings 

on dark brown or 

black body

Habitat includes moist deciduous, mixed deciduousconiferous, and coniferous forests; breeds in seasonal 

pools or fi shless permanent pools; favors sandy soils

Endangered: Del., N.J., Va. Extirpated: Pa.

Threatened: Md.

Description: p. 51

4.3 – 7.5 inches

(11 – 19 cm)

Light blue-gray 

fl ecks on brown or 

gray body

Habitat includes deciduous forests; breeds in seasonal 

pools or fi shless permanent pools

Protected: N.J., Va. Watch list: Md., W. Va.

Description: p. 53

SPOTTED SALAMANDER

(Ambystoma maculatum)

Indicator Species

MARBLED SALAMANDER

(Ambystoma opacum)

Indicator Species

JEFFERSON SALAMANDER

(Ambystoma jeffersonianum)

Indicator Species

Note: Unlike the other 

Ambystoma spp. that breed 

during spring, A. opacum

breeds during fall 

Photo: USGS PWRC Photo: USGS PWRC

Photo: John F. Bunnell Photo: Steven M. Roble

Field Guide 1: Salamanders of seasonal pools in the mid-Atlantic region.*

EASTERN TIGER SALAMANDER

(Ambystoma tigrinum tigrinum)

Indicator Species
Field Guide to Seasonal Pool Fauna 39

3 – 4.7 inches 

(7.5 – 12 cm)

Bluish-white or 

gray fl ecks on 

light brown to black body 

Habitat includes hardwood forests or mixed pinehardwood forests; breeds in seasonal pools and fi shfree ponds

Special Concern: Va.

Description: p. 56

BLUE-SPOTTED SALAMANDER

(Ambystoma laterale)

Indicator Species

MABEE’S SALAMANDER

(Ambystoma mabeei)

Indicator Species

MOLE SALAMANDER

(Ambystoma talpoideum)

Indicator Species

3 – 5.5 inches 

(7.5 – 14 cm)

Bluish-white 

spots on gray, 

brown or black body 

Habitat includes deciduous and mixed deciduousconiferous forests with rotting logs and deep humus; 

also inhabits forests surrounding wetlands; breeds in 

seasonal pools and fi sh-free ponds

Endangered: N.J.

Description: p. 54

3 – 4.8 inches 

(7.5 – 12 cm)

White or gray 

fl ecks on sides 

of gray or black 

body

Habitat includes pine savanna, wet wood, and swamp 

habitats; breeds in seasonal pools

Threatened: Va.

Description: p. 55

Photo: Jason D. Gibson

Photo: Solon Morse, RTPI Photo: Steven M. Roble

Field Guide 1: Salamanders of seasonal pools in the mid-Atlantic region.
40 An Introduction to Mid-Atlantic Seasonal Pools

Field Guide 1: Salamanders of seasonal pools in the mid-Atlantic region.

RED-SPOTTED NEWT

(Notophthalmus viridescens viridescens)

Facultative Species

FOUR-TOED SALAMANDER

(Hemidactylium scutatum)

Facultative Species

Adult (above): 

2.3 – 5 inches

(7 – 13 cm);

olive to brown 

with distinctive 

black-bordered red spots

Eft (below): 1.5 – 3.5 inches (4 – 9 cm); bright orange to 

dull red with spots

Adult habitat includes wide-range of semi-permanent and 

permanent waters 

Efts (juveniles) are terrestrial

Protected: Del., N.J., Va.

2 – 4 inches

(5 – 10 cm)

Rusty brown 

body with gray 

sides; four toes on hind feet; white underside with black 

spots

Habitat includes mature hardwood forests and oak-pine 

forests; breeds in seasonal pools or other wetlands; lays 

eggs above the water line; often nests in sphagnum and 

other mosses

Protected: Del., N.J., Va.

Photos: Solon Morse, RTPI Photo: Solon Morse, RTPI
Field Guide to Seasonal Pool Fauna 41

Field Guide 2: Frogs and toads of seasonal pools in the mid-Atlantic region.*

WOOD FROG

(Rana sylvatica)

Indicator Species

1.4 – 2.8 inches 

(3.5 – 7 cm)

Brown or redbrown with 

characteristic 

chocolate mask; white underbelly; two ridges extend along 

sides of back

Habitat includes moist or lowland deciduous woods; breeds 

in fi sh-free seasonal and sometimes permanent pools

Protected: Del., N.J., Va.

Description: p. 57 

2 – 2.6 inches 

(5 – 6.6 cm)

Color changes 

from light green 

to brown; white stripe on upper lip extends down body 

sides; usually has dorsal spots; large toe disks

Habitat includes coastal plain woodlands; breeds in 

seasonal pools 

Endangered: Del., Md.

Threatened: Va.

Photo: Steven M. Roble

EASTERN SPADEFOOT

(Scaphiopus holbrookii)

Indicator Species

BARKING TREEFROG

(Hyla gratiosa)

Facultative Species

GRAY TREEFROG

(Hyla versicolor/Hyla chrysoscelis)

Facultative Species

1.8 – 3 inches 

(4.4 – 7.3 cm)

Smooth skin with 

scattered warts; 

sharp black 

spades on hind feet; vertical pupils and yellow eyes

Habitat includes fl oodplains of streams and rivers, woods, 

meadows, or fi elds with loose, sandy soils; breeds in 

seasonal pools

Protected: Del., N.J., Va. 

Watch List: W. Va.

Description: p. 59

Note: Eastern spadefoots 

primarily breed in seasonal 

pools with short hydroperiods, 

including ephemeral pools. 

Note: In parts of its 

range, H. gratiosa may 

be an indicator species. 

1.3 – 2.4 inches 

(3.2 – 6 cm)

Highly variable 

body color 

changing from gray/green/brown; white spot under eye; 

large toe disks 

Habitat includes forest and seasonal pools, permanent 

water, and swamps; breeds in seasonal pools

Note: In the southern part Protected: Del., N.J., Va.

of its range, H. versicolor/ 

chrysoscelis may be an 

indicator species. 

* General information on the frogs and toads is derived from Tyning (1990), Green and Pauley (1987), Hulse et al. (2001), Schwartz and Golden (2002), and 

White and White (2002). All sizes given for frogs and toads represent ‘snout to vent’ lengths (SVL) and do not include the legs. Lengths are primarily from 

Conant and Collins (1998) and represent the range of average SVL of these species; where the literature of the mid-Atlantic region gave different fi gures, the 

widest range of lengths was selected. Distribution maps are adapted from the ARMI National Atlas for Amphibian Distributions (http://www.pwrc.usgs.gov/

armiatlas/). Maps may not accurately refl ect the current presence of species in counties (see website for more information).

Photo: John F. Bunnell

Photo: Alvin Braswell

H. versicolor H. chrysoscelis

Photo: Farmscape Ecology Program, Hawthorne Valley Farm, NY
42 An Introduction to Mid-Atlantic Seasonal Pools

0.8 – 1.4 inches

(2 – 3.6 cm)

Brown or gray 

with 3 dark stripes 

or broken markings down back; dark stripes from snout to 

groin, passing through the eye; small toe disks

Habitat includes grassy fl oodplains and wet woodlands; 

breeds in shallow annual and semi-permanent pools/

wetlands

(P. f. f.) Protected: N.J., Va.

 Watch list: W. Va.

Field Guide 2: Frogs and toads of seasonal pools in the mid-Atlantic region.

PINE BARRENS TREEFROG

(Hyla andersonii)

Facultative Species

PINE WOODS TREEFROG

(Hyla femoralis)

Facultative Species

UPLAND CHORUS FROG/

NEW JERSEY CHORUS FROG

 (Pseudacris feriarum feriarum/

Pseudacris feriarum kalmi)

Facultative Species

1.1 – 2 inches 

(2.8 – 5 cm)

Bright green body 

with purple stripes 

down sides; white 

belly; large toe disks

Found in New Jersey Pine Barrens; breeds in seasonal 

pools to permanent impoundments

Endangered: N.J.

1 – 1.5 inches 

(2.5 – 3.8 cm)

Highly variable 

body color 

ranging from 

reddish-brown to green-gray; row of very small orange, 

yellow, or white spots on rear of thighs; large toe disks

Habitat includes pine fl atwoods and cypress swamps on 

coastal plain; breeds in seasonal pools

Protected: Va.

BRIMLEY’S CHORUS FROG

(Pseudacris brimleyi)

Facultative Species

1 – 1.3 inches 

(2.5 – 3.3 cm)

Variable color 

with bold 

black stripes down sides from snout to groin, passing 

through eye; 3 brown or gray stripes down back; small 

toe disks

Habitat includes wet woods and swamps of coastal 

plain; breeds in shallow annual and semi-permanent 

pools/wetlands

Protected: Va.

(P. f. k.) Protected: Del., N.J., Va. 

 Endangered: Pa.

Photo: John F. Bunnell

Photo: John F. Bunnell

Photo: Joseph Mitchell

Photo: Steven M. Roble
Field Guide to Seasonal Pool Fauna 43

Field Guide 2: Frogs and toads of seasonal pools in the mid-Atlantic region.

SPRING PEEPER

(Pseudacris crucifer crucifer)

Facultative Species

NORTHERN CRICKET FROG

(Acris crepitans)

Facultative Species

EASTERN NARROWMOUTHED TOAD

(Gastrophryne carolinensis)

Facultative Species

NORTHERN/SOUTHERN 

LEOPARD FROG

(Rana pipiens/Rana sphenocephala)

Facultative Species

0.7 – 1.3 inches 

(1.9 – 3.3 cm)

Variable body 

color with brown 

imperfect ‘x’-

shaped mark on back; small toe disks

Habitat includes forest or fi eld; breeds in shallow 

seasonal or permanent pools and wetlands

Protected: Del., N.J., Va.

0.6 – 1.4 inches 

(1.6 – 3.5 cm)

Variable body 

color; triangularshaped dark 

mark between eyes; fully-webbed feet

Habitat includes moist areas near seasonal pools, 

permanent water and streams; avoids dense vegetation

Protected: Del., N.J., Va.

0.9 – 1.3 inches 

(2.5 – 3.3 cm)

Variable color; 

fold of skin across 

back of head; 

pointed snout

Habitat includes open and forested land; breeds in 

shallow wetlands, seasonal pools, fl ooded fi elds, and 

ditches

Protected: Va. 

Endangered: Md.

2 – 3.5 inches 

(5 – 9 cm)

Green and 

brown with 

irregular dark spots on back; cream dorsolateral ridges

Habitat includes grassy meadows and fi elds; breeds in a 

variety of shallow wetland habitats

(Photograph is of Southern Leopard Frog)

(R. p.) Protected: Va. (R. s.) Protected: Del., N.J., Va.

 Watch list: W. Va. Endangered: Pa.

Photo: Herb Lord Photo: USGS PWRC

Photo: Steven M. Roble Photo: USGS PWRC

Southern Northern
44 An Introduction to Mid-Atlantic Seasonal Pools

Field Guide 2: Frogs and toads of seasonal pools in the mid-Atlantic region.

CARPENTER FROG

(Rana virgatipes)

Facultative Species

PICKEREL FROG

(Rana palustris)

Facultative Species

GREEN FROG

 (Rana clamitans)

Facultative Species

AMERICAN BULLFROG

 (Rana catesbeiana)

Facultative Species

1.6 – 2.6 inches 

(4 – 6.6 cm)

Brown with 

four coppery 

stripes running 

lengthwise on backs and sides

Habitat includes sphagnum bogs, Delmarva bays, some 

beaver ponds, and swamps

Protected: Del., N.J., Va. 

Special Concern: Md., Va.

1.8 – 3 inches 

(4.4 – 7.6 cm)

Tan or brown 

with dark brown 

square blotches; 

light-colored dorsolateral ridges

Habitat includes streams, marshes, meadows, and ponds 

with thick marginal vegetation; breeds in a variety of 

wetlands

Protected: Del., N.J., Va.

2 – 4 inches

(5 – 10.2 cm)

Green to brown; 

two dorsolateral 

ridges extending two-thirds of the way down the back; 

white underside

Habitat and breeding grounds include ephemeral to 

permanent wetlands and other bodies of water including 

streams

Protected: Del., N.J., Va.

3.5 – 6 inches 

(9 – 15.2 cm); 

largest frog in 

mid-Atlantic

Green to brown; no dorsolateral ridges; two ridges extend 

on sides of face from eye around eardrum to shoulder

Habitat and breeding grounds include mostly deep, 

sometimes shallow, semi-permanent to permanent bodies 

of water

Can be a predator of seasonal pool amphibian eggs, larvae 

and adults

Protected: Del., N.J., Va.

Photo: Steven M. Roble Photo: John F. Bunnell

Photo: John F. Bunnell Photo: John F. Bunnell
Field Guide to Seasonal Pool Fauna 45

Field Guide 2: Frogs and toads of seasonal pools in the mid-Atlantic region.

AMERICAN TOAD

(Bufo americanus)

Facultative Species

FOWLER’S TOAD

(Bufo fowleri)

Facultative Species

2 – 3.5 inches 

(5 – 9 cm)

Brown with dark 

brown spots 

containing 1 to 2 warts; light mid-dorsal stripe may be 

present; parotoid gland separated from ridge behind eye; 

often has a spotted underside 

Habitat includes woodlands, fi elds, and human-dominated 

landscapes; breeds in permanent ponds, seasonal pools, 

streams, ditches, and road ruts

Protected: Del., N.J., Va.

2 – 3 inches 

(5 – 7.5 cm)

Brown with dark 

brown spots 

containing 3 - 7 

warts; light mid-dorsal stripe often present; parotoid gland 

in contact with ridge behind eye; unspotted underside 

Especially common on Coastal Plain and in sandy areas; 

breeds in seasonal pools and shallow edges of lakes and 

streams

Protected: Del., N.J., Va.

Photo: Steven M. Roble Photo: John F. Bunnell
46 An Introduction to Mid-Atlantic Seasonal Pools

Photo: Solon Morse, RTPI

Photo: Leo Kenney

Photo: Lesley J. Brown

ISOPOD

Crustacea C: Malacostraca O: Isopoda

Facultative Species

AMPHIPOD

Crustacea C: Malacostraca O: Amphipoda

Facultative Species

Field Guide 3. Invertebrates of seasonal pools in the mid-Atlantic region.*

FAIRY SHRIMP

Crustacea C: Branchiopoda O:Anostraca

Indicator Species

CLAM SHRIMP

Crustacea C: Branchiopoda O: Laevicaudata/Spinicaudata

Facultative Species

SEED SHRIMP

Crustacea C: Ostracoda O: Podocopa

Facultative Species

CLADOCERA

Crustacea C: Branchiopoda

Facultative Species

Colorful bodies

0.5 – 2 inches (12 – 51 mm)

Swim upside down with their 

11 pairs of legs in the water 

column 

Filter microbes and detritus 

Resting eggs overwinter and 

aestivate

Description: p. 60

Transparent to brown carapace 

0.1 – 0.6 inches (2 – 16 mm)

Resemble lentils

Swim slowly with their legs 

down or forward; associated with 

aquatic vegetation and the pool 

bottom; burrow in sediments 

Consume detritus or collect 

plankton 

Resting eggs overwinter and 

aestivate

Variable color

Usually less than 0.04 inches 

(1 mm)

Resemble miniature mussels or 

seeds

Filter feeds detritus; may 

scavenge dead or living animals

Found in sediments 

Resting eggs can overwinter and aestivate

“Water fl eas” or “Daphnia”

Clear or transparent

Less than 0.2 inches (5 mm); 

folded carapace

Use antennae strokes for 

movement; jerky locomotion

Filter feeds detritus, algae, and 

bacteria

Parthenogenic eggs; also produces resting eggs that can 

overwinter and aestivate

Brown to light gray

Less than 0.7 inches (18 mm)

Flattened and broad-bodied; 7 

pairs of legs

Crawl along pool bottoms

Consume detritus; scavenge on 

dead organisms 

Do not have physiological adaptations to withstand drying

“Scuds”

Variable color: pink, gray, or light 

green

0.2 – 0.4 inches (5 – 10 mm); 

narrow-bodied 

Swim in quick bursts

Consume detritus; found among 

detritus on pool bottom or buried 

in soft-bottom

May survive short dry periods by burrowing in bottom

Note: Clam shrimp inhabit 

seasonal pools with short 

hydroperiods, including ephemeral 

pools. Some species of clam 

shrimp may be indicator species for 

ephemeral pools.

P = Phylum C = Class O = Order F = Family

Photo: Leo Kenney

Photo: Solon Morse, RTPI

* Invertebrates were selected for Field Guide 3 based on the results of fi eldwork conducted in seasonal pools by Mahoney et al. (1990), Leeper and Taylor (1998), 

and Brooks (2000). Descriptions of these invertebrates were based on Wiggins et al. (1980), Kenney and Burne (2001), Smith (2001), Colburn (2004), and several 

chapters from the edited volume of Thorp and Covich (1991): Dodson and Frey, Hilsenhoff, and Smith and Cook. 

Photo: Leo Kenney
Field Guide to Seasonal Pool Fauna 47

COPEPOD

Crustacea C: Copepoda

Facultative Species

Up to 0.1 inches (2.5 mm)

Different species are fi lter 

feeders or predators 

Adults of some species may 

form cocoons to survive 

droughts; many species 

produce eggs that may enter 

diapause

FINGERNAIL CLAM

P: Mollusca C: Pelecypoda

Facultative Species

AMPHIBIOUS SNAIL

P: Mollusca C: Gastropoda

Facultative Species

CADDISFLY LARVA

P: Arthropoda C: Insecta O: Trichoptera

Facultative Species

PHANTOM MIDGE LARVA

P: Arthropoda C: Insecta O: Diptera F: Chaoboridae

Facultative Species

Cream to light brown

Less than 0.5 inches (13 mm)

Filters detritus, algae, and 

bacteria

Some species burrow in 

sediments to survive dry periods

Shells can be found in dry 

seasonal pool beds

Shells are dull brown or light 

gray; pink bodies 

Feeds on detritus and algae

Some species are annual; 

other species may 

overwinter by burrowing in 

frozen mud; also may burrow 

in leaf litter or sediments to 

survive dry season

Shells can be found in dry 

pool beds

Sheltered in self-constructed 

cases 

Two seasonal pool families:

1) Limnephilidae: “log cabin” 

cases (above)

2) Phryganeidae: grass and 

leaf cases (below)

Shred decaying leaves and 

detritus; some species also feed 

on mosquito larvae and amphibian egg masses

Live in seasonal pools and other aquatic habitats; adults 

emerge before pools dry out; cases found in dry pool beds

Eggs may overwinter 

Almost transparent; have distinct 

heads

Less than 1 inch (25 mm) 

Predators of insect larvae and 

small crustaceans 

Live in seasonal pools and 

permanent waters; adults 

emerge

Abundant in early spring 

Field Guide 3: Invertebrates of seasonal pools in the mid-Atlantic region.

Photos: Wayne Davis

PREDACEOUS DIVING BEETLE

P: Arthropoda C: Insecta O: Coleoptera F: Dytiscidae

Facultative Species

Oval body shape; long linear 

antennae

0.1 – 1.75 inches (2 – 45 mm)

Hind swimming legs are fringed 

with hairs and kick simultaneously

Feed on invertebrates and 

amphibian larvae 

Some species survive dry periods 

by burrowing in pool sediments, others by migrating to 

permanent waters; some species lay diapausing eggs

Photo: Leo Kenney

Photo: Solon Morse, RTPI Photo: Solon Morse, RTPI Photo: Leo Kenney

Photo: Solon Morse, RTPI

Photo: Leo Kenney Photo: Leo Kenney

Photo: Leo Kenney
48 An Introduction to Mid-Atlantic Seasonal Pools

LEECH

P: Annelida C: Hirundinae 

Facultative Species

AQUATIC OLIGOCHAETE WORM

P: Annelida C: Oligochaeta

Facultative Species

Field Guide 3: Invertebrates of seasonal pools in the mid-Atlantic region.

CHIRONOMID MIDGE LARVA

P: Arthropoda C: Insecta O: Diptera F: Chironomidae

Facultative Species

MOSQUITO LARVA

P: Arthropoda C: Insecta O: Diptera F: Culicidae

Facultative Species

WATER MITE

P: Arthropoda C: Hydrachnidia O: Acariformes

Facultative Species

0.1 – 0.8 inches (2 – 20 mm)

Often red due to hemoglobinlike pigment

Worm-shaped and cylindrical

Can survive in low oxygen 

levels as found in drying 

seasonal pools

Found in pool bottoms and 

open water; adults emerge

0.3 – 0.5 inches (8 – 13 mm)

Have characteristic fl ip-fl op 

swimming motion; called 

“wrigglers”

Feed on detritus and microorganisms 

Live in seasonal pools and other 

shallow waters; adults emerge

Brilliant red or green, or brown, 

tan, brown, yellow or blue

Less than 0.2 inches (5 mm)

Spherical and resembles tiny 

spiders 

Carnivorous or parasitic

Complex life cycle

Flattened and elongated; has 

oral sucker and larger caudal 

sucker

Parasites, scavengers, 

or predators (of aquatic 

invertebrate larvae and 

amphibian eggs)

Some species can burrow 

into pool bottom to survive 

short dry seasons; some species produce droughtresistant eggs

Elongated; 

up to 1.5 inches (38 mm)

Feed on leaf litter, detritus and 

soil

Found among detritus and mud 

in seasonal pools

Produce cocoons that protect 

them from short periods of 

drought

PLANARIA

P: Platyhelminthes C: Turbellaria

Facultative Species

Flat and unsegmented

0.2 – 1.2 inches (5 – 30 mm)

Live for a year or less; some 

species encyst themselves to 

survive dry period

Photo: Solon Morse, RTPI Photo: Leo Kenney Photo: Leo Kenney

Photo: Leo Kenney Photo: Leo Kenney

Photo: Leo Kenney Photo: Leo Kenney

Photo: Leo Kenney
Field Guide to Seasonal Pool Fauna 49

Mole Salamanders 

For the salamander species detailed below, please refer to Field Guide 1 for photographs of adults 

(p. 38), Field Guide 4 for photographs of eggs (p. 63), and Field Guide 5 for photographs of larvae 

(p. 66). General information on the salamanders’ physical appearance, habitat, and behavior is 

primarily derived from Petranka (1998), Bishop (1941), and Tyning (1990). Species information 

was tailored to the mid-Atlantic region by using Green and Pauley (1987), Hulse et al. (2001), 

Schwartz and Golden (2002), and White and White (2002). When there was a range of fi gures 

reported for certain parameters (such as egg clutch size), the fi gures from fi eldwork in the midAtlantic region were selected when possible, as is the case for this entire section. Salamander 

lengths represent total length of the body and tail. The lengths are primarily from Conant and 

Collins (1998) and represent the range of average total lengths of these salamanders; where midAtlantic literature provided dissimilar total lengths, the widest range of lengths was selected. 

Spotted Salamander (Ambystoma maculatum)

INDICATOR SPECIES

Adult Description: Spotted salamanders are 4.4 to 7.8 inches (11 – 20 cm) total length. These 

salamanders have bright yellow or yellow-orange spots in two rows from head to tail on black, 

bluish-black, brownish-black, or steel gray bodies (Field Guide 1). Their undersides are gray.

Habitat Requirements: As adults, spotted salamanders live primarily below ground, residing 

in small mammal burrows and beneath logs and leaf litter. They feed on invertebrates (such 

as earthworms, centipedes, spiders, and insects). Spotted salamanders inhabit moist, mature 

deciduous forests as well as younger deciduous and mixed deciduous-coniferous forests. 

Breeding occurs primarily in seasonal forest pools, seasonal forested wetland pools, and fi shfree ponds.

Reproduction: On moderate rainy or humid nights from mid-February through April, 

spotted salamanders emerge from their terrestrial burrows and migrate to pools to breed 

(Green, 1956; Nyman, 1991). At the pools, salamanders may gather in large congresses. The 

breeding season may be several days to two months long, with one to three major breeding 

events per season (Stenhouse, 1985; Harris, 1980; Petranka, 1998). Spotted salamander 

breeding phenology (time frame in months when eggs, larvae, and metamorphs are present at 

pools) for the mid-Atlantic region is shown in Fig. 3-2. 

Eggs: Within hours to a few days following mating, females lay one to four egg masses on 

submerged vegetation or debris about 8 – 10 inches (20 – 25 cm) below the water surface 

(Field Guide 4; Bishop, 1941). Freshly laid egg masses are less than 1 inch diameter but expand 

within hours as they absorb water (Bishop, 1941). Individual egg masses contain an average 

of 75 – 110 eggs per mass (range of 15 – 250 eggs) (Bishop, 1941; Wood and Wilkinson, 

1952; Shoop, 1974; Harris, 1980). Female spotted salamanders have total clutch sizes (total 

number of eggs laid per breeding effort) of around 200 eggs (Woodward, 1982; Shoop, 1974; 

Ireland, 1989). An egg mass is surrounded by a stiff gelatinous matrix, which is either clear or 

opaque white (the latter is due to the presence of a crystalline protein). This gelatinous matrix 

decreases predation, although adult red-spotted newts, predatory wood frog tadpoles, and 

caddisfl y and midge larvae may still eat the embryos (Rowe et al., 1994; Stout et al., 1992). A 

IN-DEPTH INFORMATION ON SEASONAL POOL INDICATOR SPECIES
50 An Introduction to Mid-Atlantic Seasonal Pools

week after being laid, spotted and other mole salamander egg masses may begin to take on a 

greenish hue caused by the growth of a symbiotic alga, Oophila amblystomatis, within the jelly 

matrix. This alga derives nutrients from the jelly matrix and in turn provides oxygen to the 

developing embryos (Bachmann et al., 1986; Pinder and Friet, 1994). 

Larvae: Spotted salamander larvae hatch from the eggs after about three to seven weeks, 

depending upon water temperature. Larvae are only 0.5 inch (1 cm) in length at hatching 

and grow quickly on a diet of zooplankton and other invertebrates to reach about 2 inches (5 

cm) at metamorphosis. Larvae are greenish with light-colored underbellies and large feathery 

gills (Field Guide 5). Spotted salamander larvae are preyed upon by predatory insects and 

salamander larvae (e.g., marbled and eastern tiger) (Hairston, 1987). 

Juveniles: Between six weeks and four months after hatching, mid-June through August, 

larvae metamorphose into juveniles. Slowly growing larvae in some populations may 

overwinter and transform the next spring (if the pool remains fl ooded) (Wilbur, 1977; 

Phillips, 1992) though this has not been recorded for the mid-Atlantic region. Juveniles are 

similar to adults but have lighter undersides and less prominent spotting on their backs. Sexual 

maturity occurs after two to fi ve years, with males typically maturing earlier than females. 

Range: Spotted salamanders are found throughout the mid-Atlantic region, although they 

tend to be absent from coastal areas. 

Regional Notes: In Delaware, New Jersey, and Virginia, spotted salamanders are protected 

(with limits set on take and collection). Major pressures on spotted salamander populations, as 

with the other species of mole salamanders, come largely from habitat loss and deforestation. 

Spotted salamander populations appear to have declined in eastern Virginia, which may be 

related to acidic deposition and concomitant increases in concentrations of various metals 

(aluminum, copper, silicon, and zinc) (Blem and Blem, 1989, 1991; see Section 4.3). 

Marbled Salamander (Ambystoma opacum)

INDICATOR SPECIES

Adult Description: Marbled salamanders are 3.5 to 4.3 inches (9 – 11 cm) total length and 

thick-bodied with short tails. These salamanders are shiny black to purplish-black with silverywhite or gray markings usually in crossbands, or as stripes in some individuals (Field Guide 1). 

Males have larger, more distinct silver-white markings compared with females whose markings 

are more blotchy and gray in coloration.

Habitat Requirements: Marbled salamanders spend most of their adult lives beneath leaf 

litter, debris, stones, or below ground (up to 1 m in depth) in natural crevices and mammal 

burrows. In summer and fall after rains, marbled salamanders can be found on the surface 

of the forest fl oor. They inhabit deciduous forests as well as mixed deciduous-coniferous and 

coniferous forests. Marbled salamanders depend upon seasonal pools for breeding; only very 

rarely will they breed in pools with fi sh. 

Reproduction: Marbled salamanders exhibit a very different breeding behavior than the other 

mole salamander indicator species. Breeding takes place during a different season and on 

land rather than in the water. On rainy nights in fall (September to November) courtship and 

mating begins en route to and in or along the margins of dry seasonal pool beds. In these dry 

pools, females either fi nd a naturally-occurring depression (e.g., rodent burrow immediately 

below leaf litter) or scour out their own that will serve as a nest for their eggs. The nest is an 
Field Guide to Seasonal Pool Fauna 51

oval-shaped depression about 3 inches (7 cm) long, 2 inches (5 cm) wide, and 1 inch (2 cm) 

deep (Tyning, 1990; Petranka, 1998). Nests are also created beneath logs and stones and at the 

bases of grass clumps and trees (Bishop, 1941; Petranka, 1998). Marbled salamander breeding 

phenology for the mid-Atlantic region is shown in Fig. 3-2. In an opposite pattern compared 

to the other species of mole salamanders, marbled salamander adults breed earlier in their 

northern range as compared to their southern range and earlier at higher altitudes as compared 

to lower altitudes.

Eggs: Females lay 37 – 130 eggs in their nests (Green, 1956). Although nests are usually 

individual, communal nests holding two to seven clutches have also been found (Petranka, 

1998). Females often stay with their eggs, curling their bodies around them until the pool is 

fi lled – which may be weeks or even months later. This behavior is thought to protect the eggs 

from desiccation and predation by insects or small mammals. Females deposit eggs singly and 

they often appear black due to clinging soil and detritus (Field Guide 4; Bishop, 1941; Petranka, 

1998). 

Larvae: Marbled salamander larvae hatch from eggs within a few days of being submerged by 

pool fl ooding. If they hatch in the fall, the larvae will overwinter. During the cold months they 

undergo only slow growth (Bishop, 1941), but during warm weather larvae grow quickly, fi rst 

eating zooplankton and later becoming voracious predators of invertebrates and amphibian 

larvae including sibling marbled salamander larvae (Walls and Blaustein, 1995). In early 

spring, marbled salamander larvae are likely to be larger in size than other amphibian larvae in 

seasonal pools due to earlier hatching. Larvae are brown to blackish with a row of light spots 

on their sides; older larvae develop mottling on a light yellowish-green body (Field Guide 5). 

Their throats are darkly pigmented, which may distinguish them from lighter-throated spotted 

salamander larvae. 

Juveniles: The larvae begin transforming in the early spring and most leave the pool by May 

or June. Recent metamorphs have purplish-black or brown bodies with a light-colored spotted 

or speckled pattern; by one to two months after transformation, the adult pattern begins to 

appear (Bishop, 1941). Sexual maturation occurs after one to fi ve years.

Range: Marbled salamanders occur throughout the mid-Atlantic region, but appear to be 

absent from northern and western Pennsylvania, eastern West Virginia, and western Virginia 

(with the exception of a few scattered records).

Regional Notes: Like the spotted salamander, marbled salamanders are protected (with limits 

set on take and collection) in Delaware and Virginia and are listed as special concern in New 

Jersey. Loss of habitat – particularly bottomland deciduous forests and associated seasonal pool 

habitats – poses the greatest threat to existing populations of marbled salamanders (Petranka, 

1998).

Eastern Tiger Salamander (Ambystoma tigrinum tigrinum) 

INDICATOR SPECIES

Adult Description: Tiger salamanders are among the largest pool-breeding or terrestrial 

salamanders in North America. One of the approximately seven recognized subspecies, eastern 

tiger salamanders are 7.0 to 8.3 inches (17 – 21 cm) total length with a thick body and broad 

head. Eastern tiger salamanders are dark brown or dull black with a cream, greenish-yellow or 

brownish-yellow pattern of irregular blotches or spots, sometimes forming tiger-like stripes 

around their sides (Field Guide 1). They have yellowish undersides with dark marbling. 
52 An Introduction to Mid-Atlantic Seasonal Pools

Habitat Requirements: Adult eastern tiger salamanders are fossorial, spending most of 

their terrestrial lives in self-dug tunnels or in mammal burrows. They inhabit areas with 

suitable conditions for burrowing (e.g., woodlands, open areas with sandy soils). Eastern tiger 

salamanders breed in seasonal pools and fi shless permanent ponds (Bishop, 1941; Wilbur and 

Collins, 1973).

Reproduction: Tiger salamanders migrate to breeding pools from their underground 

hideaways earlier than spotted salamanders on rainy or damp nights. Their breeding season 

occurs from December to March across the mid-Atlantic region (Fig. 3-2; Cooper, 1955; 

Anderson et al., 1971). The breeding season in New Jersey lasts about two months, which may 

be longer than other mole salamanders in the area (Hassinger et al., 1970). They congress in 

smaller groups compared to spotted salamanders (White and White 2002). Males produce 

larger spermatophores than other ambystomatids. 

Eggs: Females lay their eggs in globular or oblong gelatinous masses on twigs, weed stems, 

and other structures in ponds at depths greater than 20 cm (Field Guide 4; Hassinger et al., 

1970). Egg masses measure 2.0 by 2.75 inches (5.5 by 7.0 cm) and swell in size and lose their 

turgidity as they absorb water. Individual egg masses typically contain 30 – 60 eggs (Hassinger 

et al., 1970; Stine et al., 1954; Bishop, 1941). Females have an average clutch size of 344 – 421 

eggs (Wilbur, 1977; Stine et al., 1954). 

Larvae: Eastern tiger salamander eggs hatch after four to seven weeks, depending upon water 

temperature (Stine et al., 1954; Hassinger et al., 1970). Hatchlings have gray bodies with dark 

bands across or blotches along their backs and whitish bellies; older larvae have olive green 

bodies with markings (Field Guide 5). Eastern tiger salamander larvae are larger than other 

Ambystoma spp. larvae in the region. Some larvae develop a cannibalistic morphology, typifi ed 

by larger size and enlarged teeth (though this has not been observed in the mid-Atlantic 

region) (J.C. Mitchell, pers. comm.). 

Juveniles: Larvae transform after two and a half to four months in late spring and summer. 

Juveniles are initially dark gray or dark brown, and begin to attain adult coloration within one 

month of transformation. Sexual maturation occurs generally when two to three years old 

(Semlitsch, 1983). 

Range: Eastern tiger salamanders are found mainly in eastern coastal areas of Delaware, 

Maryland, southern New Jersey, and southeastern Virginia; they are not found in Pennsylvania 

and West Virginia. There is also one relict population in the Shenandoah Valley (Blue Ridge 

Mountains) of Virginia disjunct from other populations (Buhlmann and Hoffman, 1990; 

Church et al., 2003).

Regional Notes: Tiger salamanders are listed as ‘Endangered’ in Delaware, Maryland, New 

Jersey, and Virginia. They are considered extirpated from Pennsylvania as a result of habitat 

alteration and loss (Hulse et al., 2001). The loss of vernal pools, Delmarva bays, and upland 

forests is threatening these salamanders on the Delmarva Peninsula (Sipple, 1999; White and 

White, 2002). Fish stocking and acid deposition also have contributed to declines of tiger 

salamander populations in Virginia (Buhlmann et al., 1999). 
Field Guide to Seasonal Pool Fauna 53

Jefferson Salamander (Ambystoma jeffersonianum)

INDICATOR SPECIES

Adult Description: Jefferson salamanders are 4.3 to 7.5 inches (11 – 19 cm) total length and 

are slender with long tails and elongated limbs and triangular-shaped toes. They are chocolate 

brown to dark gray and have light blue or gray speckles on their limbs, lower sides and tail 

(Field Guide 1). Flecks are bright on young adults, but may fade with age. Their undersides are 

lighter than their sides and are also speckled. Jefferson salamanders are physically distinguished 

from blue-spotted salamanders by their slightly larger size, smaller markings, gray area around 

the vent (as compared to black area in the blue-spotted salamander), and broader head. 

Habitat Requirements: Juvenile and adult Jefferson salamanders spend a majority of their 

lifetimes below ground, feeding on earthworms and other invertebrates. They reside in 

deciduous forests, and are more likely than the other mole salamander species to live in upland 

forests. In West Virginia, Jefferson salamanders have been found in caves (Green and Brant, 

1966). Seasonal forest pools are the usual breeding location, but semipermanent pools, farm 

ponds, and fl oodplain pools may also be used (Petranka, 1998). 

Reproduction: In the mid-Atlantic region, Jefferson salamanders breed early in the spring, 

beginning in February or March when evening rains coincide with temperatures of 40° F or 

more (Fig. 3-2; Petranka, 1998; Hulse et al., 2001). Males often mount the female (dorsally 

with forelimbs grasped behind the female’s) for a time before more courtship occurs and 

spermatophores are deposited. Jefferson salamander spermatophores are about twice the size 

of those deposited by blue-spotted salamanders.

Eggs: One or two days after mating, female Jefferson salamanders deposit their eggs as masses 

attached to submerged vegetation or unattached in the seasonal pool water. When attached to 

solid structures such as twigs and branches, egg masses tend to be cylindrical and clumped in 

groups; when attached to more vegetative substrates, such as grass, the egg masses are more 

irregular in shape and laid further apart from each other (Field Guide 4; Petranka, 1998). Each 

female lays up to 300 eggs in separate egg masses of 10 – 75 eggs (Martof et al., 1980, Hulse et 

al., 2001). 

Larvae: The eggs usually hatch after four to six weeks, but the embryonic period may last as 

long as 14 weeks depending upon water temperature (Martof et al., 1980, Petranka, 1998). 

Hatchlings are olive green to brown with hints of yellow on the sides of the neck, head and 

dorsal fi n (Field Guide 5). Mature larvae have grayish bodies with heavily mottled broad dorsal 

fi ns, broad heads, elongated and tapered toes, and a silvery or white belly. Larvae are voracious 

feeders, eating small zooplankton at fi rst, then progressing to larger invertebrates, including 

snails and insects. They are also known to eat spotted salamander larvae and other Jefferson 

salamander larvae (Petranka, 1998). 

Juveniles: The larval period lasts two to fi ve months (J.C. Mitchell, pers. comm.). Metamorphs 

are uniformly gray or brownish above with muted brownish yellow specks on the sides. 

Jefferson salamanders become sexually mature after two to three years.

Range: Jefferson salamanders are patchily distributed in the mid-Atlantic states. They are 

found in northern New Jersey, most of Pennsylvania, western Maryland, and along the Blue 

Ridge and Allegheny Mountains of Virginia and the Allegheny Plateau of West Virginia. They 

are absent from Delaware.
54 An Introduction to Mid-Atlantic Seasonal Pools

Regional Notes: Jefferson salamanders are on the watch list (special concern but without 

legal protection) in Maryland and West Virginia, are of special concern in New Jersey, and are 

protected (have limits set on take or collecting) in Virginia. Jefferson salamanders appear to 

be more vulnerable to acidic conditions than other amphibians (Petranka, 1998). Jefferson 

salamanders were designated by the Northeast Endangered Species Technical Committee 

as a species of regional conservation concern due to their risk of extirpation (Therres, 

1999). Jefferson and blue-spotted salamanders often hybridize in areas where their ranges 

overlap, resulting primarily in female polyploids, which could lead to a reduction in pure 

Jefferson salamander populations (Bogart and Klemens, 1997). In the mid-Atlantic states, 

triploid hybrids known as Ambystoma platineum (having two sets of Jefferson salamander 

chromosomes and one set of blue-spotted salamander chromosomes) have been confi rmed 

genetically in New Jersey (Schwartz and Golden, 2002) and may exist but are not confi rmed in 

eastern Pennsylvania (Hulse et al., 2001). 

Blue-spotted Salamander (Ambystoma laterale)

INDICATOR SPECIES

Adult Description: Blue-spotted salamanders are 3 to 5.5 inches (7.5 – 14 cm) total length 

with bluish white spots and fl ecks on a purplish-brown, dark gray or black body (Field Guide 

1). Blue spots may stand in sharp contrast against the body color or appear rather muted. 

Compared to the Jefferson salamander, blue-spotted salamanders are generally smaller, have 

larger bluish spots distributed on the sides as well as the back, and have darker pigmentation 

around the vent. 

Habitat Requirements: Blue-spotted salamanders are fossorial, spending a majority of their 

time in deciduous or mixed deciduous-coniferous forests with rotting logs and deep humus. 

They also inhabit forested areas above the water level in swamps and marshlands. However, 

compared to other ambystomatids, blue-spotted salamanders are more likely to be found 

active on the surface during warmer months. They feed primarily at night on earthworms, 

slugs, isopods and other arthropods. Breeding occurs in fi sh-free pools, including seasonal 

forest pools, seasonal open-canopy pools, semipermanent pools, wetlands, and ditches. 

Reproduction: Mating occurs in water in late winter or early spring, and generally consists of 

one to three explosive breeding occasions per year, which are triggered by warm, rainy nights. 

Courtship behavior resembles that of the Jefferson salamander and is described in detail by 

Storez (1969). Spermatophores of blue-spotted salamanders are about half the size of those 

of Jefferson salamanders. Blue-spotted salamander breeding phenology for the mid-Atlantic 

region is shown in Fig. 3-2. 

Eggs: Females lay eggs singly, in strings of two to four eggs, or, less frequently, as poorlydefi ned masses of 2 – 30 eggs, on the pool fl oor or attached to leaf litter, vegetation, sticks, or 

rocks (Field Guide 4). The total number of eggs that a female deposits in a breeding season 

ranges from 100 – 500. 

Larvae: Eggs typically hatch about a month after deposition. Larvae are dark brown with 

yellow blotches and paired black spots on either side of the tail fi n on the back. Each side has a 

light elongated stripe, the undersides are unpigmented, and the tail fi ns are broad and mottled 

with black (Field Guide 5). Larvae most likely feed on zooplankton and dipteran larvae 

(Petranka 1998). The larval period typically lasts two to three months. 
Field Guide to Seasonal Pool Fauna 55

Juveniles: Just after metamorphosis, juveniles have yellowish spotting on both their backs and 

underbellies. Juvenile blue-spotted salamanders become mature in about two years.

Range: In the mid-Atlantic states, blue-spotted salamanders are confi rmed only in northern 

New Jersey (Anderson and Giacosie, 1967).

Regional Notes: This species is listed as Endangered in New Jersey. Blue-spotted salamanders 

may have a greater tolerance for disturbed areas than Jefferson salamanders, but this tolerance 

may make them more susceptible to other threats associated with human development 

(Klemens, 1993). In New Jersey, blue-spotted salamanders have experienced high road 

mortality and have had lowered reproductive success in degraded pools with poor water 

quality (Schwartz and Golden, 2002). Blue-spotted salamanders have declined with the 

conversion of hardwood forests to urban and agricultural areas. Jefferson and blue-spotted 

salamanders often hybridize when their ranges overlap, which may reduce the population size 

of pure diploid blue-spotted salamander populations (Bogart and Klemens, 1997).

Mabee’s Salamander (Ambystoma mabeei)

INDICATOR SPECIES

Adult Description: Mabee’s salamanders are 3 to 4.8 inches (8 – 12 cm) total length and are 

dark brownish gray to black with silvery white or gray fl ecks mostly on the sides with a few on 

the back (Field Guide 1). Mabee’s salamanders have a relatively small head and long slender 

toes. Their undersides are light gray to grayish brown with scattered light-colored fl ecks. 

Habitat Requirements: Mabee’s salamanders are found in pine savanna, wet woods, and 

swamp habitats in southeastern Virginia. In the pine savanna, they inhabit burrows at the edges 

of bogs and ponds and migrate long distances to forested areas in the non-breeding season 

(J.C. Mitchell, pers. comm.). Mabee’s salamanders breed in fi sh-free seasonal pools, including 

seasonal forest pools, sinkhole ponds, Carolina bays, semipermanent farm ponds, and cypresstupelo ponds in pinewoods (Hardy and Anderson, 1970). 

Reproduction: The breeding biology of Mabee’s salamanders is not well-studied (Petranka 

1998). According to Hardy (1969) breeding occurs from winter to early spring, but according 

to Martof et al. (1980) breeding starts as early as late fall; it is also reported to occur between 

December and March in Virginia (Fig. 3-2; J.C. Mitchell, pers. comm.). 

Eggs: Females attach eggs singly or in loose chains of two to six eggs to leaves, twigs, and debris 

on the bottom of shallow pools (Field Guide 4). 

Larvae: Hatchlings are 1/3 inch (0.85 cm) total length and have a single yellow stripe on either 

side of the body, bushy gills, and a broad dorsal fi n that extends onto the back (Field Guide 

5). Older larvae are brown to blackish with two cream stripes along the sides of the body that 

are often broken; dorsal and ventral fi ns are heavily mottled. Mabee’s salamander larvae from 

Virginian populations feed heavily on isopods and amphipods (McCoy and Savitsky, 2004). 

Larvae transform in late spring at sizes of about 2 inches (5 – 6 cm) total length. 

Juveniles: Juveniles are initially black or dark gray above with little or no light fl ecking. Time 

to sexual maturation is unknown.

Range: In the mid-Atlantic region, Mabee’s salamanders are only found in southeastern 

Virginia.
56 An Introduction to Mid-Atlantic Seasonal Pools

Regional Notes: Mabee’s salamanders are listed as threatened in Virginia. The range of 

the Mabee’s salamander was not discovered to extend into Virginia until 1979 (Mitchell 

and Hedges, 1980). The Mabee’s salamander is one of the least-studied species of mole 

salamanders, with many aspects of their biology and natural history unknown (McCoy and 

Savitsky, 2004). Larval Mabee’s salamanders from Virginian populations were found to have 

signifi cantly higher gastric parasitic nematode loads as compared to those from North and 

South Carolinian populations (McCoy and Savitsky, 2004). Habitat loss from ditching and 

draining of breeding sites and conversion of forests to agricultural lands has presumably 

impacted this species (Petranka, 1998).

Mole Salamander (Ambystoma talpoideum)

INDICATOR SPECIES

Adult Description: Mole salamanders are 3 to 4.7 inches (7.5 – 12 cm) total length, and are 

stocky with large limbs, short tails, and large heads. Their backs and sides range in color from 

light brown to light bluish gray to dark brown or blackish and are speckled with small bluish 

white or grayish fl ecks (Field Guide 1). Their undersides are bluish gray with light fl ecks.

Habitat Requirements: Mole salamanders live in underground burrows or tunnels in pine 

savannas, hardwood forests, fl oodplain forests, and swamps. In Virginia, mole salamanders 

are primarily found in upland and lowland deciduous forests or mixed deciduous-coniferous 

forests. Mole salamanders breed in fi sh-free pools, including seasonal forest pools, seasonal 

forested wetland pools, Carolina Bays, and roadside ditches. They are more successful in pools 

that do not also support populations of spotted salamanders (Hayslett, 2003). 

Reproduction: Breeding typically occurs after long sustained rains and cooler temperatures of 

40 – 45° F (Hayslett, 2003). Mole salamanders exhibit a range of migration dates to breeding 

pools and breeding season durations that are dependent upon environmental conditions 

(Semlitsch, 1985a; Hayslett, 2003). In Virginia, the time spent at breeding pools was found to 

extend from mid-October to early May during a wet year and from late-January to early-April 

in a dry year (Hayslett, 2003). Males arrive earlier and stay longer at the pools compared to 

females (Semlitsch, 1981). Mole salamander breeding phenology for the mid-Atlantic region is 

shown in Fig. 3-2. 

Eggs: Females lay eggs singly along the pool bottom on leaves, grass, and twigs (Semlitsch 

1985a) at depths of 2 – 12 inches (A. Braswell, pers. comm.). Total clutch sizes for a single 

female are approximately 200 – 700 eggs, with clutch size and egg size increasing with female 

age (Field Guide 4; Semlitsch, 1985a; Hayslett, 2003). 

Larvae: Eggs hatch after 30 – 40 days (Semlitsch et al., 1988). Hatchlings have alternating 

black and yellow blotches along the midline of the back and on the tail fi n. Older larvae 

develop two cream or dull yellow stripes on each side that break up toward the tail, as well 

as a characteristic dark band that extends along the midline of the belly, which is retained in 

juveniles and gilled adults (Field Guide 5). 

Juveniles: Larvae may start metamorphosing by mid-June (North Carolina, A. Braswell, 

pers. comm.). If larvae have not metamorphosed by mid-July, they may overwinter, become 

sexually mature and reproduce as paedomorphs the following spring and then metamorphose 

to terrestrial form (Hayslett, 2003; A. Braswell, pers. comm.). This reproductive strategy of 
Field Guide to Seasonal Pool Fauna 57

paedomophosis primarily occurs in pools that do not dry annually (Semlitsch, 1985b). A 

paedomorph, or gilled adult, is darker than an immature larva and may be lacking the midline 

dark stripe on its belly. Newly transformed juvenile mole salamanders are brownish green in 

color. About 2 – 4 weeks after transformation, adult patterns (gray fl ecking) begin to appear. 

In South Carolina, the majority of mole salamanders become sexually mature in the fi rst year, 

within a few months of transformation (Semlitsch et al., 1988). 

Range: In the mid-Atlantic region, mole salamanders only occur in south central Virginia in 

an area geographically disjunct from the rest of the species’ range (Bader and Mitchell, 1982). 

Regional Notes: The mole salamander is a species of special concern in Virginia. Loss of 

upland forests as well as seasonal and semipermanent pools impacts populations of this 

species. 

Frogs

For the frog species detailed below, please refer to Field Guide 2 for photographs of adults (p. 41), 

Field Guide 4 for photographs of eggs (p. 65), and Field Guide 5 for photographs of larvae (p. 

68). General information on the frogs’ physical appearance, habitat, and behavior were compiled 

from Tyning (1990), Green and Pauley (1987), Hulse et al. (2001), Schwartz and Golden (2002), 

and White and White (2002). All sizes given for frogs represent ‘snout to vent’ lengths (SVL) and 

do not include the legs. Lengths are primarily from Conant and Collins (1998) and represent the 

range of average SVL of these species; where the literature of the mid-Atlantic region gave different 

fi gures, the widest range of lengths was selected. 

Wood Frog (Rana sylvatica)

INDICATOR SPECIES

Adult Description: Wood frogs are 1.4 to 2.8 inches (3.5 – 7 cm) SVL and vary in color from 

gray brown to dark brown or reddish-brown with a pale white or cream-colored underbelly 

and dark crossbars on the hind legs (Field Guide 2). Two dorsolateral ridges extend along the 

sides of the back. Wood frogs have a characteristic dark chocolate brown mask that extends 

from the snout across the eyes to a point behind the eardrum (tympanic membrane). Males 

are usually darker and smaller than females. Males are dark gray brown and have enlarged 

thumbs during the breeding season, while females are usually reddish-brown. 

Habitat Requirements: As its common name implies, wood frogs inhabit primarily moist or 

lowland deciduous woods. In northern Pennsylvania, wood frogs are also found in hemlocknorthern hardwood-white pine communities (Hulse et al., 2001). Outside of hibernation 

and breeding times, wood frogs are active on the forest fl oor during the day and night if 

temperatures exceed 53° F and if humidity is high or it has rained. In winter, wood frogs 

hibernate in deciduous forests underneath leaf litter or cover objects or in shallow burrows 

rarely below the frostline of the soil, making wood frogs susceptible to freezing conditions. 

However, wood frogs can withstand temperatures as low as 20° F before freezing because they 

release high levels of glucose into their body fl uids from liver glycogen stores, which acts as an 

antifreeze agent (cryoprotectant). Wood frogs can also survive up to two weeks of extracellular 

freezing at moderate subzero temperatures (Storey and Storey, 1986). Wood frogs breed in fi shfree seasonal and sometimes permanent pools in or adjacent to forests, including vernal pools, 

beaver ponds, roadside ditches, canals, and borrow/gravel pits.
58 An Introduction to Mid-Atlantic Seasonal Pools

Reproduction: Wood frogs are the fi rst anurans to breed in the calendar year in most of 

the mid-Atlantic region. On a warm, wet evening in late winter or early spring, wood frogs 

migrate from their woodland habitats to breeding ponds for an explosive two to seven days of 

mating. Males may vocalize in pools for up to three to four weeks, but females are typically in 

pools for only one to a few days. Freezing weather may interrupt breeding for a period of time. 

At the Patuxent Research Refuge, a 13,000 acre refuge in Maryland, wood frogs may breed at 

some seasonal pool sites a week or more before breeding commences at other sites, most likely 

a result of variation in temperature and microhabitat. Wood frog breeding phenology for the 

mid-Atlantic region is shown in Fig. 3-2. 

Eggs: Females deposit one egg mass containing approximately 500 – 1000 eggs on vegetation 

or sticks beneath the surface of the water that the male quickly fertilizes (Field Guide 4). At 

deposition, wood frog eggs are tightly packed together with no outer surrounding jelly matrix 

unifying the mass, giving the mass a bumpy appearance on the water surface. Egg masses have 

a diameter of about 2.5 to 4 inches (6.3 – 10 cm). After a week or more, egg masses become 

amorphous and harder to count individually and may turn green due to algal growth. Females 

usually deposit egg masses in the same general area of a pool every year. In a woodland 

setting, this is often on the north side of the pool where the ice melts fi rst; this area receives 

the most solar exposure. Eggs are most often laid in large communal oviposition sites or rafts 

that help to trap heat and accelerate development. Seale (1982) reported one raft of 963 wood 

frog egg masses at a pool in Pennsylvania. 

Larvae: Wood frog eggs hatch after two or three weeks. Tadpoles are medium-sized, up to 

2 inches (5 cm) in length and are dark brown to blackish with gold fl ecking (Field Guide 

5). Their underbellies are pale iridescent. Eyes are dorsally located just above the sides, not 

bulging out on sides laterally like tadpoles in the treefrog (Hylidae) family. Initially, they 

attach themselves to their disintegrating egg mass with their sucker-like mouths and graze the 

algae growing on its surface. For the remainder of the larval stage, they feed primarily on algae 

and detritus (although they may also eat smaller siblings or cohorts) and fi nd refuge in the 

leaf litter at the bottom of the pool and in large schools in shallow areas of the pool. 

Juveniles: Tadpoles metamorphose into their terrestrial form 60 – 113 days later, usually 

sometime in June and July (Berven, 1988; Tyning, 1990). At metamorphosis, froglets look like 

miniature adults. Sexual maturation occurs after one to two years for males and after two to 

three years for females (Berven, 1990). 

Vocalizations: Male wood frog advertisement calls during the breeding season sound like 

duck quacks, repeated one to fi ve times. Males call day and night. 

Range: Found throughout the mid-Atlantic region except for southeastern Virginia. 

Regional Notes: Wood frogs are protected with limits set on take and collection in Delaware, 

New Jersey, and Virginia.
Field Guide to Seasonal Pool Fauna 59

Eastern Spadefoot (Scaphiopus holbrookii)

INDICATOR SPECIES

Adult Description: Eastern spadefoots are 1.8 – 3 inches (4.4 – 7.6 cm) SVL, short-legged, 

and stout. They have bulging eyes, rounded heads and snouts, and smooth skin with scattered 

small tubercles (warts). Their backs are olive or brown or gray to black with two irregular 

yellow lines running from behind their eyes down the length of their backs meeting at a 

midline near the rump (Field Guide 2). Sometimes they have an additional yellowish line 

on the side of the body. Their throat and chest are white, except during the breeding season 

when males’ throats darken. The spadefoot’s common name is derived from the dark, horny 

growth on the inner sides of each hind foot, which facilitates digging. Unlike almost all North 

American frogs, spadefoots have vertical pupils; they also have greenish-yellow irises. 

Habitat Requirements: Eastern spadefoots live below ground, burrowing in loose, sandy soils 

in river fl oodplains, woods, meadows, or fi elds. Breeding occurs in short-hydroperiod seasonal 

or ephemeral pools. They are adapted to dry conditions and can survive prolonged droughts, 

sometimes for years, lying dormant below the surface. During these dry periods they excrete a 

fl uid that hardens around their curled-up bodies to prevent desiccation (Tyning, 1990).

Reproduction: On mild afternoons and evenings in the spring (starting as early as February), 

summer, or fall, during or just after periods of very heavy rains and low barometric pressure, 

spadefoots dig out from their burrows to breed in recently fi lled seasonal pools or ditches. They 

are explosive and unpredictable breeders and may appear by the dozens or even hundreds to 

breed following a heavy storm. The male grasps the female in an inguinal amplexus, just above 

her hind legs; other species of male frogs in the region grasp females behind the front legs. 

During the breeding season, males develop black cornifi cations on the fi rst three fi ngers of the 

front feet. Eastern spadefoot breeding phenology for the mid-Atlantic region is shown in Fig. 

3-2.

Eggs: Eggs are laid and fertilized externally on underwater vegetation. Each female may deposit 

up to 2500 eggs in strands or bands that are 1 – 2 inches wide (2.5 – 5 cm) and up to 12 inches 

long (30 cm); as the eggs swell with water, they clump into more irregular bunches (Field 

Guide 4). 

Larvae: Spadefoot eggs hatch very rapidly, after 1 day to one week, depending on water 

temperature (Richmond, 1947). Tadpoles are dark bronze to dark brown and have close-set 

eyes near the top of their head (Field Guide 5). The tail fi ns are translucent and are unmarked. 

Spadefoot tadpoles spend the fi rst one to four days relatively inactive, attached to their egg 

mass or other objects. Then, tadpoles swim throughout the pool (near the water surface if the 

pool is deep) feeding on plankton. Between one and two weeks after they hatch, tadpoles form 

dense schools, feeding continuously on algae and carrion (Richmond, 1947). 

Juveniles: Typically, spadefoots transform into juveniles after about a month (range of two 

to ten weeks) of larval development, depending upon water temperature and larval density 

(Richmond, 1947; Semlitsch and Caldwell, 1982; Tyning, 1990). Newly transformed eastern 

spadefoot juveniles congregate in large numbers around the pool for several days after 

metamorphosis (Richmond, 1947). They are active during the day foraging near their natal 

ponds. Juveniles reach maturity at about 2 inches (5 cm) at two years of age (Pearson, 1955). 

Vocalizations: The advertisement calls of male spadefoots are loud, abrupt grunts or squawks 

that sound like a downward-slurred “errrrrrgh,” often repeated in rapid succession. 
60 An Introduction to Mid-Atlantic Seasonal Pools

Range: Eastern spadefoots are found in lowland areas of the Coastal Plain and some of the 

adjacent Piedmont areas, with very scattered distributions in mountainous areas (Martof et al., 

1980; Mitchell and Reay, 1999). They are absent from northwestern Maryland, northwestern 

Pennsylvania, northern Virginia and are known from only a few places in West Virginia.

Regional Notes: Eastern spadefoots are on the watch list (special concern without legal 

protection) in West Virginia and are protected (with limits set on take and collection) in 

Delaware, New Jersey, and Virginia. Eastern spadefoots are rarely seen or heard except after 

heavy rain events, undergo rapid development, and spend much of their lifetime underground. 

For these reasons, the distribution of this species has not been thoroughly elucidated. 

Fairy Shrimp

Crustaceans in the class Branchiopoda include fairy shrimps, tadpole shrimps, clam shrimps, 

and water fl eas. With the exception of water fl eas, which occur ubiquitously in many freshwater 

habitats, the Branchiopods are among the most distinctive inhabitants of seasonal pools (Smith, 

2001). The primarily freshwater order Anostraca, the fairy shrimp, has 50 documented species in 

the United States (Belk, 1975; Smith, 2001). Fairy shrimp in particular have become emblematic of 

seasonal pools, and are considered an indicator species group of mid-Atlantic seasonal pools. 

Fairy shrimp: Order Anostraca 

INDICATOR SPECIES

Adult Description: Fairy shrimp adults range in total length from 0.5 to almost 2 inches 

(1.2 – 5 cm). Their coloration is variable, and may be partially dictated by the food they eat; 

they occur in colors of gray, blue, green, orange, and red (Field Guide 3; Smith, 2001). These 

crustaceans glide gracefully about the pool swimming upside down with 11 pairs of swimming 

legs waving above, fi ltering their food.

Habitat Requirements: Fairy shrimp feed on microbes and detritus in the water column 

or substrate (Smith, 2001). Fairy shrimp tend to do better in seasonal pools with short 

hydroperiods (Mahoney et al., 1990). They appear in seasonal pools in late winter or early 

spring, completing their life cycle in a short period before predatory insects reach maximum 

densities (Wiggins et al., 1980). 

Reproduction: Detailed species-specifi c reproductive biology of most fairy shrimps is not well 

known. The following is a general account; there are likely differences among species. During 

courtship, male fairy shrimp clasp the female with antennae and they swim together around 

the pool for days at a time. After copulation, which only lasts several seconds, eggs are carried 

externally in the female’s brood sac for one to several days. During this time the eggs undergo 

early development. Females lay one to six clutches of eggs per season at two to six day intervals. 

Clutch size is 10 – 250 eggs (Smith, 2001). Some fairy shrimp may produce two types of eggs 

– thin-shelled eggs that hatch quickly and thick-shelled eggs that are more hardy. The latter of 

these two types, the resting (dormant) eggs, allow fairy shrimp to exploit seasonal pools and 

to maintain their populations through the dry season of the pools and through freezing winter 

conditions. Fairy shrimp eggs are dormant from 6 to 10 months per year in the mid-Atlantic 

region before hatching during pool fl ooding. Not every egg will hatch – eggs may stay viable 

buried in the seasonal pool bed sediments for many years. Resting eggs may be transported 

in the wind or by birds, insects, or salamanders (Lowcock and Murphy, 1990; Bohonak and 
Field Guide to Seasonal Pool Fauna 61

Whiteman, 1999; Smith, 2001). Metamorphic Ambystoma salamanders may ingest female fairy 

shrimp and defecate in another pool, thereby transporting their eggs (Bohonak and Whiteman, 

1999). 

Range: Four species from two families have been recorded for the mid-Atlantic region: three 

species of Eubranchipus in the family Chirocephalidae and one species of Streptocephalus in the 

family Streptocephalidae. In addition, another species (Eubranchipus neglectus) may be found 

in the mid-Atlantic region, though this is not confi rmed (Belk, 1975, Belk et al., 1998). 

Regional Notes: There is very little published research on Anostraca of seasonal pools in the 

mid-Atlantic region. Additionally, there has been confusion surrounding the records of species 

distributions due to mistakes in identifying two species (Belk et al., 1998). Adult fairy shrimp 

tend to be unpredictable in occurrence and abundance and exhibit a patchy distribution 

across the landscape. They may be sporadic in appearance from one year to the next, or may 

be abundant for many successive years, then suddenly disappear. Eggs may remain viable in 

the pool bottom for years until hatching. Pools in close proximity to a pool with a particular 

species of fairy shrimp may have different species of fairy shrimp or none at all (Smith, 2001). 

Family Scientifi c Name States in the Mid-Atlantic Region

Chirocephalidae Eubranchipus holmanii Md., N.J., Pa., Va.

Chirocephalidae Eubranchipus neglectus W. Va.* and southwestern Va.*

Chirocephalidae Eubranchipus serratus Md., Va.

Chirocephalidae Eubranchipus vernalis Del., Md., N.J., Pa., Va., W. Va.*

Streptocephalidae Streptocephalus sealii Md., N.J., Va.

Species of fairy shrimp in the mid-Atlantic region. These species distributions are based on Belk 

(1975) and Belk et al. (1998). Belk (1975) created distributions using published records and specimens 

from the National Museum of Natural History, Washington, D.C. 

* These species have not been recorded from these states, but according to range maps, they may occur there (see 

Belk et al., 1998).
62 An Introduction to Mid-Atlantic Seasonal Pools

COMPARISON OF EGGS AND LARVAE OF AMPHIBIAN INDICATOR SPECIES

The presence of egg masses and larvae provides evidence of use of the pools by amphibians for 

breeding. Depending on the species, eggs may be laid singly, in strings, in sheets, or as discrete 

masses. Females may lay eggs individually or in communal areas of pools. Eggs and egg masses 

of seasonal pool breeders are usually attached to vegetation or woody debris below the water 

surface (with the notable exception of the marbled salamander). Egg masses of species of mole 

salamanders are encapsulated by a jelly matrix that ranges in consistency from very fi rm (spotted 

salamanders) to medium-fi rm (Jefferson salamanders) to soft (blue-spotted salamanders). The 

jelly matrix is usually clear, although spotted salamander egg masses may be opaque white due to 

the presence of a crystalline protein. Frog egg masses, in contrast, lack this outer jelly matrix and 

are less cohesive than mole salamander egg masses. Amphibian egg masses change in appearance 

over time in the seasonal pools. They swell in size and become more amorphous as they absorb 

water. Also, egg masses may begin to take on a greenish hue caused by the growth of a symbiotic 

alga, Oophila amblystomatis, within the jelly matrix. This alga derives nutrients from the jelly 

matrix and in turn provides oxygen to the developing embryos (Pinder and Friet, 1994).

Mole salamander egg masses can also be distinguished from one another based on characteristics 

of the eggs. Spotted salamander eggs exhibit a large distance between the inner envelope and 

vitelline membrane, such that the vitelline membrane is much farther from the embryo compared 

to those of blue-spotted and Jefferson salamanders (Kenney and Burne, 2001). Photographs and 

descriptions are provided to aid in the identifi cation of eggs of indicator species by highlighting 

distinctive characteristics (Field Guide 4). 

Amphibian larvae are often more diffi cult to identify to species than the egg masses. Several mole 

salamander larvae in particular are diffi cult to distinguish from one another. Photographs and 

descriptions are provided to aid in the identifi cation of larvae of indicator species by highlighting 

distinctive characteristics (Field Guide 5).

Comparison of 

relative dimensions 

of eggs. Spotted 

salamander eggs 

(left) exhibit a 

larger distance 

between the inner 

envelope and the 

vitelline membrane 

as compared 

to blue-spotted 

and Jefferson 

salamander 

eggs (right). This 

characteristic aids in 

fi eld identifi cation of 

eggs to the correct 

species of mole 

salamander.
Field Guide to Seasonal Pool Fauna 63

SPECIES DESCRIPTION LOCATION

Field Guide 4. Amphibian eggs in mid-Atlantic seasonal pools.*

# of Eggs per Mass: 

Average of 75 – 110 

(total clutch up to 250)

Clear or opaque white

Globular to oval; very fi rm 

jelly-like matrix

Large distance between inner 

envelope and vitelline membrane

Attached to sticks, 

stems, aquatic 

vegetation; up to 8 

– 10 inches or more 

below water surface

# of Eggs per Mass: 

Laid singly

(total clutch 37 – 130)

Eggs often appear black due 

to clinging dirt

Eggs laid singly in nest 

depression; no cohesive 

outer envelope, but eggs are 

grouped

Eggs have a fi rm, sticky outer 

membrane

Nests located in 

dried seasonal 

pool beds; scoured 

in pool bottom or 

located in rodent 

burrows, beneath 

cover objects, or at 

water’s edge

# of Eggs per Mass: 

Average of 30 – 60

(total clutch up to 421)

Masses 2 – 2.8 inches 

diameter

Globular or oblong; matrix 

initially very fi rm but becomes 

very loose

Attached to twigs, 

stems, and vegetation; in water 

greater than 8 

inches deep

Photos: USGS PWRC

Photo: USGS PWRC Photo: USGS PWRC

* Information on amphibian eggs was primarily derived from Bishop (1941), Tyning (1990), Petranka (1998), and Kenney and Burne 

(2001).

Photo: James W. Petranka

Spotted Salamander

Marbled Salamander

Eastern Tiger Salamander
64 An Introduction to Mid-Atlantic Seasonal Pools

Field Guide 4. Amphibian eggs in mid-Atlantic seasonal pools.

SPECIES DESCRIPTION LOCATION

Jefferson Salamander

# of Eggs per Mass: 

10 – 75

(total clutch up to 300)

Masses clear and cryptic

Cylindrical on branches 

and irregular on grasses; 

intermediate fi rm matrix

Attached to submerged branches 

or grasses

Photo: Leo Kenney

Photo: Steven M. Roble Photo: Steven M. Roble

# of Eggs per Mass: 

1 – 30 

(total clutch 100 – 500 eggs)

Masses clear

Eggs laid singly, in strings

of 2 – 4, or in poorly-defi ned 

masses of 2 – 30

Attached to 

submerged 

branches, stems, 

and leaves; 8 

– 10 inches below 

surface or on pool 

fl oor

Photo: Steven M. Roble Photo: Steven M. Roble

Blue-Spotted Salamander

# of Eggs per Mass: 

2 – 6

(total clutch size unknown)

Eggs laid singly or in strings 

of 2 – 6

Attached to leaves, 

twigs, and debris in 

shallow pools

Photo: Karen Sheffield Photo: Karen Sheffield

Mabee’s Salamander
Field Guide to Seasonal Pool Fauna 65

Field Guide 4. Amphibian eggs in mid-Atlantic seasonal pools.

SPECIES DESCRIPTION LOCATION

Eggs are darkly pigmented 

on top and white below

Eggs laid singly or in small 

loose clusters

Attached to 

submerged twigs 

and stems in 

shallow pools

Photo: Alvin Braswell Photo: Alvin Braswell

# of Eggs per Mass: 

Laid singly

(total clutch approx. 200 – 700)

Mole Salamander

Masses clear

Globular; no outer jelly matrix; 

grape cluster appearance

Often attached to 

twigs and stems; 

often deposited 

communally; look 

like lumpy sheets 

just below water 

surface

Photo: USGS PWRC Photo: USGS PWRC

# of Eggs per Mass: 

500 – 1000

Wood Frog

Strands or bands 1 – 2 

inches wide and up to 12 

inches long

Attached to 

underwater or 

fl oating vegetation 

in shallow pools

Photo: John F. Bunnell Photo: John F. Bunnell

# of Eggs per Mass: 

Up to 2500 

Eastern Spadefoot
66 An Introduction to Mid-Atlantic Seasonal Pools

Field Guide 5. Amphibian larvae in mid-Atlantic seasonal pools.*

* Information on amphibian larvae was primarily derived from Bishop (1941), Tyning (1990), Petranka (1998), and Kenney and Burne (2001).

SPECIES DESCRIPTION NOTES

Hatchlings light gray, 

becoming brown; row of light 

spots on sides below limbs

Older larvae light olive to 

brown to almost black; pale 

spots on head and light 

yellow-green blotches on 

back and tail; throat and 

underside pigmented; row 

of light spots on sides below 

limbs

Throats darker 

than spotted 

larvae; largest mole 

salamander larvae 

in early spring due 

Photo: John F. Bunnell to earlier hatching

Photo: Leo Kenney Photo: Leo Kenney

Marbled Salamander

Hatchlings gray or yellowish 

green; dark bands along 

backs; white undersides

Older larvae olive-green 

or dark brown with black 

markings; light underside; 

throats generally lack 

pigment

Flattened spade- or 

triangular- shaped 

toes; all other mole 

salamanders have 

rounded toes; 

larger-sized than 

other species of 

mole salamander 

larvae

Photo: Steven M. Roble Photo: Steven M. Roble

Eastern Tiger Salamander

Hatchlings dull olive; no 

markings

Older larvae greenish-yellow 

with light ventral surface; no 

markings on chin and throat; 

tail fi n mottled with black

More slender than 

blue-spotted larvae; 

bushier gills

Photos: Solon Morse, RTPI

Spotted Salamander
Field Guide to Seasonal Pool Fauna 67

Field Guide 5. Amphibian larvae in mid-Atlantic seasonal pools.

SPECIES DESCRIPTION NOTES

Hatchlings brown with single 

yellow stripe on each side of 

body

Older larvae brown to 

blackish with two cream 

stripes along sides; fi ns 

heavily mottled

Only occur in southeast Va. in the midAtlantic region

Photo: Steven M. Roble

Mabee’s Salamander

Larvae olive green to brown; 

hints of yellow on sides of 

neck, head, dorsal fi n

Older larvae grayish with 

heavily mottled dorsal fi ns; 

broad heads; long toes; 

silvery or white belly

Diffi cult to distinguish 

from other mole 

salamander larvae

Photo: Leo Kenney Photo: Leo Kenney

Jefferson Salamander

Photo: Solon Morse, RTPI

Photo: Steven M. Roble

Hatchlings dark brown with a 

yellow stripe on each side

Older larvae dark brown with 

yellow blotches; paired black 

spots on either side of tail fi n 

on backs; light lateral bands 

on sides; unpigmented undersides; broad black-mottled 

tail fi ns

Diffi cult to distinguish 

from other mole 

salamander larvae

Blue-Spotted Salamander
68 An Introduction to Mid-Atlantic Seasonal Pools

Field Guide 5. Amphibian larvae in mid-Atlantic seasonal pools.

SPECIES DESCRIPTION NOTES

Photo: John F. Bunnell Photo: John F. Bunnell

Eastern Spadefoot

Dark brown to bronze; 

close-set eyes near top of 

head; tail fi ns translucent

Form dense schools

Photo: Solon Morse, RTPI

Hatchlings black

Older larvae dark brown 

to blackish with gold fl ecking; pale underbellies; 

light line along side of 

snout where mouth will 

later form; side of snout 

darker than rest of body

May form large 

schools in shallows

Wood Frog

Photos: Alvin Braswell

Mole Salamander

Hatchlings have black and 

yellow blotches on back 

midline and tail fi n (above)

Older larvae have two 

cream stripes on each 

side; on undersides there 

are single black lines 

(below)

Only occur in southcentral Va. in the 

mid-Atlantic region

The alternative 

adult form 

(paedomorph) is 

darker than the 

immature larva 
Appendix A: Techniques to Locate Seasonal Pools 69

APPENDIX A

TECHNIQUES TO LOCATE SEASONAL POOLS

Locating and mapping seasonal pools should be a conservation priority because an inventory of 

seasonal pool distribution and status is currently unavailable in the mid-Atlantic region. Appendix 

A gives an overview of techniques that can be used to locate seasonal pools, and points the reader to 

sources of additional information. 

Step 1: Pre-Identifi cation Techniques

The following methods are considered “pre-identifi cation” techniques because they locate potential 

seasonal pools. These potential pools need to be verifi ed to ascertain that they are indeed seasonal 

pools (see Step 2). 

Aerial Photography

Description: Aerial photography is an unobtrusive method for locating landscape features, such 

as potential vernal pools, across a large geographic area (Stone, 1992; Jensen, 2000). Seasonal 

pool identifi cation will be easiest if the photograph is taken during a relatively wet year in late fall, 

winter, or early spring when deciduous leaves are not on the trees and there is no snow. Largerscale photographs are better suited for identifying seasonal pools. For example, photos at a scale of 

1:4,800 (or 1 inch = 400 feet) are better than photos at a scale of 1:12,000 (or 1 inch = 1000 ft) for 

correctly identifying seasonal pools (Calhoun et al., 2003). Scales of at least 1:12,000 to 1:4,800 are 

necessary to identify potential seasonal pools. 

Notes: Color infrared (CIR) or black and white fi lm can be used for the aerial photographs (Plate 

4-1). CIR is more useful because it highlights the presence of water. On CIR photos, pools appear 

black because water absorbs color infrared light, contrasting with lighter-colored vegetated areas 

(pink, orange, yellow). Compared to black and white, CIR fi lm provides better differentiation 

between tree shadows and small pools, discrimination of depth and permanence of water, 

detection of pools under dense canopies, and differentiation of land-cover types (Stone, 1992). 

The use of black and white aerial photography, though not as consistent and accurate as CIR, is 

also a valuable tool (and signifi cantly less expensive than CIR). On black and white aerials, pools 

appear black, though they may also appear in various shades of gray if dominated by vegetation. 

Utilizing stereoscopic sets of photographs (viewed with a stereoscope) allows analysis of the 

landscape in three-dimensions (Jensen, 2000). This technique greatly improves fi nding seasonal 

pools and depressions (Calhoun, 2003). Stereoscopes used in previous seasonal pool studies 

include a 2X pocket stereoscope and a mirror stereoscope (Stone, 1992; Pawlak, 1998). In a 

study in Massachusetts, 52% of potential vernal pools identifi ed from 1:4,800 black and white 

photographs, using a 2X pocket stereoscope, were determined to fi t the physical description 

of vernal pools (isolated depressions that hold water for two continuous months) after a fi eld 

survey (Stone, 1992). In a study in deciduous forests of Maine, 93% of potential vernal pools 

identifi ed from 1:4,800 scale black and white photographs, using panchromatic stereophotos, were 

determined to be actual vernal pools after a fi eld survey (Calhoun et al., 2003).

A digital orthophoto quadrangle (DOQ) or quarter-quadrangle (DOQQ) is a computer-generated 

image of an aerial photograph which has been orthorectifi ed (i.e., altered so that it has the 

geometric properties of a map) to allow accurate measurements of ground distance on the photos. 
70 An Introduction to Mid-Atlantic Seasonal Pools

This ensures that the photos can be used with automated mapping and Geographic Information 

System (GIS) software along with other digital cartographic data.

Regardless of fi lm types used, having assistance from someone with photo-interpretation training 

and experience with local ecology will greatly enhance the success of pre-identifi cation aerial 

photography (Stone, 1992).

Challenges: Because seasonal pools are typically small, they may be diffi cult to identify on 

aerial photos (Tiner, 1990; DiMauro and Hunter, 2002). There are challenges to using aerial 

photographs: 1) available aerial photographs may be out of date or incomplete and scheduling 

a fl y-over for new aerial photographs is very costly; 2) pools located under dense coniferous, 

deciduous or mixed canopy cover may be very diffi cult to pick out; 3) shadows of trees can 

obscure pools or be mistaken for pools; 4) clusters of conifers on black and white photos often 

show up as dark spots that look like pools; and 5) small pools are less likely to be identifi ed 

compared to large pools (Stone, 1992; Calhoun et al., 2003). 

Additional Resources: Burne (2001) provides detailed guidance on using aerial photographs 

to identify potential seasonal pools. Aerial photographs are typically available from federal, 

state, or county sources, or off the web (e.g., USGS: http://geography.usgs.gov, USDA: http://

www.nrcs.usda.gov/technical/maps.html).

U.S. Geological Survey Topographic Maps 

Description: The U.S. Geological Survey (USGS) produces topographic (topo) maps at a 1:24,000 

scale (or 1 inch = 2000 feet), commonly known as 7.5-minute quadrangle maps. These maps 

utilize contour lines to convey the three-dimensional landscape on a two-dimensional map. Both 

natural and man-made features are shown on these maps. 

Notes: On topo maps, seasonal pools may be associated with or identifi ed by contours designating 

depressions, wet spot symbols, and small ponds. Concentrations of these features indicate 

particularly good areas to search for seasonal pools. 

Challenges: Because seasonal pools tend to be small in size, only contain water for part of the 

year, and may be diffi cult to assess outside of a wet season, they often do not feature on USGS 

topo maps (Williams, 1987).

Additional Resources: Topographic maps can be purchased from outdoor equipment stores and 

bookstores or can be ordered from the USGS (http://geography.usgs.gov).

U.S. Fish & Wildlife Service National Wetland Inventory Maps 

Description: The U.S. Fish and Wildlife Service began developing a series of topical maps of the 

United States’ water resources in 1974 as part of a National Wetland Inventory (NWI) based on a 

wetland classifi cation system developed by Cowardin et al. (1979) (NWI 2002). 

Notes: On NWI maps, areas where seasonal pools are likely to be found can be identifi ed 

by looking for: 1) wetlands not connected to streams or lakes, 2) wetland classes that are 

hydrologically isolated, including ponds (PUB (palustrine unconsolidated bottom), POW 

(palustrine open water)), marshes (PEM (palustrine emergent), PAB (palustrine aquatic bed)), wet 

meadows (PEM (palustrine emergent)), shrub swamps (PSS (palustrine scrub shrub)) or forested 

wetlands (PFO (palustrine forested)). In some cases, as on the USGS topo maps, large seasonal 

pools may be identifi ed on NWI maps as ponds. 
Appendix A: Techniques to Locate Seasonal Pools 71

Challenges: Only forested wetlands greater than approximately 0.5 – 1.2 ha in size and unforested 

wetland areas greater than 0.4 ha in size are shown on NWI maps; most seasonal pools are smaller 

than these sizes and thus will be diffi cult to detect (Tiner, 1990; DiMauro and Hunter, 2002; 

Tiner, 2003a, b). NWI maps should not be the only source used to locate potential seasonal pools 

because they will disproportionately locate the largest pools.

Additional Resources: Full descriptions and defi nitions of NWI wetland codes (e.g., PFO1A) 

can be obtained on the NWI website (http://www.nwi.fws.gov/mapcodes.htm). Many NWI maps 

are now available in digital format for public use. A mapping tool called the Wetlands Mapper is 

offered by the U.S. Fish and Wildlife Service, which allows the user to produce customized maps 

(http://wetlandsfws.er.usgs.gov). Hard copies of NWI maps can be purchased from CooperatorRun Distribution Centers (http://wetlands.fws.gov/distribution_ctrs.htm).

Step 2: Verifi cation

Ground-truthing

Description: Ground-truthing (fi eld surveying), the practice of surveying the land on foot, is 

essential for validating the presence of a seasonal pool. Ground-truthing is always required to 

verify whether what you have identifi ed as a potential seasonal pool using an aerial photograph or 

map is indeed a seasonal pool. Additional pools not previously identifi ed using aerial photographs 

or maps may be discovered during ground-truthing of potential pools. Ground-truthing can 

reveal as many as 25% more pools than identifi ed from aerial photographs alone (Calhoun et al., 

2003). In a study in Massachusetts, 79% of pools discovered in fi eld surveys that were missed from 

aerial photographs were within 25 meters of other photo-selected pools (Stone, 1992). 

Notes: Once having identifi ed a potential seasonal pool on an aerial photograph, their location 

should be transferred onto maps to aid in fi eld location (Stone, 1992). Photo-identifi ed seasonal 

pools should be verifi ed in the fi eld early in the process, which can allow the photo-interpreter to 

correct or adjust the “search image” or “pool signature” to the conditions of the date and type of 

aerial photo used (Stone, 1992). 

Alternative Techniques: 

Systematic Ground-truthing

Description: Ground-truthing has been used to cover areas systematically. 

Notes: Stone (1992) searched 201 m long by 20 m wide strip plots selected from a grid array using 

a stratifi ed random design. DiMauro and Hunter (2002) and Calhoun et al. (2003) used 1200 

m stratifi ed random transects (500 m one direction, 200 m at 90 degree turn, 500 m at another 

90 degree turn) within 1 km2

 grid squares to ascertain density and characteristics of pools not 

identifi ed on aerial photographs or NWI maps. Because seasonal pools may be clustered in the 

landscape, ARMI-NE used an adaptive cluster sampling approach to survey for vernal pools at 

National Parks (Delaware Water Gap National Recreation Area, Gettysburg National Historic 

Park, Rock Creek Park, Shenandoah National Park) and National Wildlife Refuges (Canaan 

Valley, Erie, Great Swamp, Patuxent, Wallkill River) in the mid-Atlantic region. A systematic 

grid of points set 500 m apart was established on each Park or Refuge and sets of 20 points were 

randomly selected for survey. After navigating to a point, a 50 m2

 plot around that point was 

searched for seasonal pools. If no pools were found, the surveyor went to the next point. If pools 

were found, an adaptive cluster sampling approach was adopted, in which additional 50 m2 plots 

adjacent to plots with vernal pools were surveyed, ad infi nitum. 
72 An Introduction to Mid-Atlantic Seasonal Pools

GIS-Modeling

Description: Several states and studies have used GIS technology to model the locations of vernal 

pools across the landscape. 

Notes: In New Jersey, the Rutgers University Center for Remote Sensing & Spatial Analysis 

is using on-screen digitizing, image processing, and GIS coverages including freshwater 

wetlands, soil type, land use-land cover, digital elevation models, and color infrared digital 

orthophotography to identify likely areas of vernal pool occurrence. Once areas are identifi ed 

using GIS, image interpretation and fi eldwork were used to verify actual vernal pool 

occurrence in the Highlands, Pinelands, and Delaware Bayshore landscape regions (http://

www.dbcrssa.rutgers.edu/ims/vernal). In Massachusetts, Grant (2005) used modeling approaches 

and found that certain landscape features such as land use, surfi cial geology, and topography 

could predict the occurrence of a seasonal pool. Stone (1992) found that the presence and amount 

of forest cover surrounding a pool, elevation, and surfi cial geology (glaciolacustrine lake bottom 

deposits) were characteristics useful in identifying areas with a high potential for supporting 

seasonal pools with indicator species.
Appendix B: Techniques to Monitor Seasonal Pool 73

APPENDIX B

TECHNIQUES TO MONITOR SEASONAL POOLS

This appendix outlines techniques that may be used to document a pool’s location and to record 

what animals are using the pool. As highlighted in this manual, seasonal pools are a valuable 

resource, but their distribution is poorly recorded for the mid-Atlantic region. Information on 

their distribution and the species they support may be incorporated into a monitoring program 

or database. New Jersey currently has the only formal statewide program for seasonal pool 

documentation and certifi cation in the mid-Atlantic region; their requirements for documentation 

are referred to among the techniques. For precise requirements of the New Jersey Department of 

Environmental Protection Land Use Regulation Program “vernal habitat,” refer to the Freshwater 

Wetlands Vernal Habitat Protocol (http://www.state.nj.us/dep/landuse/forms/vernalpr.doc or http:

//www.state.nj.us/dep/landuse/fww/vernal/index.html). 

Documenting the Location of a Seasonal Pool

Note: New Jersey requires 1) a metes and bounds description, aerial photograph, professional 

survey, or GPS coordinates; 2) a symbol on a standard map (USGS topo) to show the pool’s 

location; and 3) a sketch map/written description.

Metes and Bounds Description

Provide written directions for locating the pool; include compass bearings and accurate measured 

distances (of 1000 feet or less) from at least two permanent landmarks. Also include distinctive 

permanent landmarks along the path of travel. 

Aerial Photograph

If an aerial photograph is available on which the seasonal pool is clearly visible, highlight its 

location.

GPS Coordinates

Use a global positioning system (GPS) receiver and record UTM (Universal Transverse Mercator) 

or latitude and longitude coordinates along with an estimated position error. 

Symbol on Standard Map

Mark the pool’s location and two permanent landmarks on a photocopy of an 8.5” by 11” section 

of a USGS topographical map, a tax assessor’s map, or a NWI map. Make sure that the map has all 

the information on it (e.g., quadrangle name, map scale) necessary to relocate the pool. 

Sketch Map

Draw the pool relative to at least two permanent landmarks; include distances and compass 

bearings.

Photograph of the Pool

Take photographs of the pool in its landscape setting to aid relocation of the site and to document 

the pool’s surroundings and hydroperiod at the time. Note the pool location, day and time of the 

photo, and the direction of the photo. 
74 An Introduction to Mid-Atlantic Seasonal Pools

Finding and Documenting Indicator Species

It is diffi cult to estimate the population sizes of seasonal pool animals. Except during their brief and 

weather-dependent breeding seasons, adult pool-breeding amphibians are rarely observed above 

ground. During winter, adult amphibians hibernate beneath the leaf litter or in small mammal 

burrows, and thus appear absent from the surrounding landscape (Madison, 1997; Faccio, 2003). If 

breeding does occur, developing amphibians and invertebrates may be observed in the pool from 

late winter until they metamorphose or the pool dries out. 

Note: To meet the “required fi eld observations for certifying a vernal habitat” in New Jersey, obligate 

(indicator) or facultative species must be either 1) photographed, 2) videotaped, 3) audio recorded 

(in the case of frog and toad calling), or 4) described in writing. 

 

Prractices to Prevent Negative Impacts to Pool Inhabitants 

Handling of fauna should be avoided unless absolutely necessary for identifi cation and 

photodocumentation (Box B-1). Handling amphibians presents challenges. Improper handing 

of amphibians may cause skin damage that could lead to secondary infections or may create 

bone and muscle injuries (Green, 2001). For detailed information on handling amphibians, 

refer to the USGS National Wildlife Health Center’s Standard Operating Procedure (http://

www.nwhc.usgs.gov/research/amph_dc/sop_restraint.html). Another major concern is the spread 

of disease-causing agents such as fungi, bacteria, and viruses between pools or animals. For more 

information on practices to prevent the spread of amphibian diseases, refer to The Declining 

Amphibian Population Task Force (DAPTF) Fieldwork Code of Practice (http://ventura.fws.gov/

es/protocols/dafta.pdf). 

Do not disturb nesting or mating animals.

Rather than holding amphibians in your hands after capture, immediately place 

them in a zip lock bag or a plastic tub for a short period of time: 

• Zip lock bags or plastic tubs must contain enough seasonal pool water to cover the gills 

and entire body of larvae.

• Lung-breathing adults should not be submerged and should have access to air as well 

as moist or wet areas within bags or tubs. 

Avoid injury to animals: 

• Do not handle amphibians with hands that have been applied with insect repellent or 

moisturizing lotions.

• Wet hands before handling amphibians to minimize damage to their outer protective 

layer of skin.

• Never hold or pull a salamander by its tail – it may break off.

• Return animals to their exact place of capture. 

• When an animal is removed from beneath an object such as a log or stone, replace the 

object fi rst, then release the animal next to it so it can crawl back under. 

Box B-1

Practices for safely handling and reducing disturbance to amphibians* 

(Continued)
Appendix B: Techniques to Monitor Seasonal Pool 75

Avoid spreading disease: 

• Wash hands thoroughly before and after handling an animal – especially before 

handling an animal from another pool.

• Thoroughly clean and disinfect boots, waders, nets and any other objects introduced 

into a pool between sites (remove all mud and debris; use bleach for disinfection).

Do not remove egg masses from the pool or detach them from vegetation:

• They are sensitive to water depth and location. 

• The matrix that protects many egg masses may be disturbed with handling, 

increasing their susceptibility to predators or disease.

• If eggs do become detached, try to reattach them or situate them at the same depth 

and in the same area. Egg masses on the bottom of pools are subject to siltation and 

low dissolved oxygen concentrations and are less likely to hatch.

Avoid seining; it causes too much disturbance.

* Beebee, 1996; Green, 2001; White and White, 2002; Calhoun, 2003

Evidence of Breeding Indicator Species

A minimum of two visits during daylight hours in the spring is recommended to document 

breeding indicator species at a seasonal pool. Visits during mid- and late summer are also 

recommended to document larvae and emerging juveniles and to determine whether the pool 

retained water long enough for successful population recruitment. Visiting pools at night may be 

treacherous and there is a greater chance for inadvertent disturbance to the pools. In general, avoid 

unnecessarily walking in or directly around the pool edge. If entering the pool, move slowly and 

carefully to avoid disturbing the habitat and animals or dislodging egg masses attached to branches 

in the water. 

Evidence of seasonal pool use by indicator species includes the egg masses, larvae, and adults 

of ambystomatid salamanders, wood frogs, and eastern spadefoots and adult fairy shrimp. 

Suggestions for fi nding these species along with tips for photography are below. Unless required by 

a seasonal pool program that will lead to possible protection of the pool, we recommend taking a 

‘hands-off’ approach to documenting the animals (e.g., photographing and identifying egg masses 

from the shore of the pool) to minimize impacts to these small ecosystems. 

Amphibian Egg Masses: Identifying egg masses is a simple and low-impact way of recognizing 

use of the pool by indicator species. Refer to Fig. 3-2 to determine what time of year egg masses 

of indicator species are most likely present. Wearing polarized sunglasses increases clarity and 

depth of vision beneath the surface of the water. If vegetation is scarce, egg masses, particularly 

those of ambystomatid salamanders, may be on the bottom of the pool. Search for egg masses 

primarily in water depths less than three feet within three to ten feet of shore around fallen logs, 

vegetation or sticks/debris. Distinguish between egg masses of all indicator species in your area 

(Field Guide 4). Egg masses are best photographed using a polarizing fi lter on your camera. 

Wood frog egg masses tend to be in large communal rafts in the parts of the pool that receive 

the most sunlight and warm up and ice out the earliest. 

Amphibian Larvae and Transforming Individuals: Salamander larvae can be easily 

distinguished from frog and toad larvae (tadpoles) – salamander larvae have bushy external 

gills while tadpoles do not (refer to Field Guide 5). Refer to Fig. 3-2 for what time of year larvae 

and transforming individuals of indicator species are most likely to be present. During the day, 
76 An Introduction to Mid-Atlantic Seasonal Pools

salamander larvae tend to hide on the bottom of the pool beneath vegetation and detritus. 

Wood frog and eastern spadefoot tadpoles often congregate in schools in shallow parts of the 

pool. Dipnets (aquarium dip nets or D-shaped dip nets) or scoops may be used to capture 

larvae; once captured, they should be transferred quickly into a water-fi lled container. 

Transformed individuals respire with lungs rather than gills so they should not be submerged 

in water. To photograph larvae, keep them in water in a container, place a white background 

behind the container, and use a camera with a polarized lens. Ideally, try to get photographs 

of larvae from above, the side, and below. 

Adult Amphibians: Adult frogs and salamanders are best found by carefully searching 

the water’s edge and the terrestrial area adjacent to the pool beneath logs, rocks, and other 

debris. Wood frogs may be found in the pool itself day or night during the breeding season 

when males are calling. In general, it is not necessary to handle these amphibians in order 

to identify them. If it is necessary to photograph adults for documentation, follow these 

suggestions for handling. Most salamanders in cool spring weather move slowly and can 

be caught by hand by gently grasping in the middle of the body between forelimbs and 

hindlimbs (Green, 2001). Hold them in your cupped wet hand or place them in a container 

with a moist surface (e.g., with wet leaves or shallow water). Frogs, however, will require an 

active pursuit, by quickly bringing a cupped hand over them on land or using a dipnet on 

land or in water. Hold frogs and toads gently but fi rmly around the waist with hindlimbs 

extended to prevent kicking (Green, 2001). Alternatively, place the frog or toad in a deep 

container or a container with a lid (so it can’t leap or hop out) with a moist surface on the 

bottom. Photograph adults from slightly above and off to one side of the individual and try 

to fi ll the frame of the photo with the animal. 

Fairy Shrimp: Adult fairy shrimp tend to be unpredictable in occurrence and their 

distribution is not at all well known for the mid-Atlantic region (see Field Guide for the life 

history of fairy shimp). Because fairy shrimp are delicate, it is best to catch and examine them 

using plastic tubs or bins dipped into the water, letting the water and fairy shrimp fl ow into 

the container. After describing and photographing them, gently release them back to the pool 

by submerging the container in the water and letting them swim out. For most purposes, 

identifying fairy shrimp as in the Order Anostraca is suffi cient. Species identifi cation is 

diffi cult and requires examining a male specimen under a dissecting microscope (see Belk, 

1975 and Belk et al., 1998 for identifi cation). 
Appendix C: Programs to Locate, Map, Monitor, and/or Protect Seasonal Pools 77

Appendix C gives an overview of seasonal pool-related projects, initiatives, and programs 

occurring in the mid-Atlantic region, including work carried out by nongovernmental 

organizations, state and local agencies, and federal agencies. Many universities are also carrying 

out related research on pool-breeding amphibians and invertebrates, but are not included in 

this summary. 

Regional Programs

There are no comprehensive region-wide initiatives to locate, map, or monitor seasonal pools 

in the mid-Atlantic. However, efforts sponsored by the USGS span National Parks and National 

Wildlife Refuges across the region. The USGS Amphibian Research and Monitoring InitiativeNortheast region (ARMI-NE) is mapping seasonal pools and monitoring amphibians at the 

pools at selected National Parks (Delaware Water Gap National Recreation Area, Gettysburg 

National Historic Park, Rock Creek Park, Shenandoah National Park) and National Wildlife 

Refuges (Canaan Valley, Erie, Great Swamp, Patuxent, Wallkill River) in the mid-Atlantic 

region (see http://www.pwrc.usgs.gov/nearmi for more information). Also, scientists at the 

USGS Leetown Science Center (LSC) have mapped all and monitored many seasonal pools in 

Delaware Water Gap National Recreation Area. 

Mid-Atlantic State and Local Programs 

District of Columbia

We are aware of two efforts to locate and map seasonal pools taking place in D.C. 

ARMI-NE (see “Regional Programs”) has mapped seasonal pools and monitors seasonal 

pool-breeding amphibians in Rock Creek Park, a 1755-acre National Park. The Nature 

Conservancy has mapped seasonal pools in the Potomac Gorge area of the Chesapeake and 

Ohio Canal National Historic Park that traverses both D.C. and Maryland. 

Delaware

There has not been a program undertaken at the state level to locate, map, monitor, or 

protect seasonal pools in Delaware. However, state wetland maps and GIS data layers show 

locations of approximately 1,500 Coastal Plain Ponds (CPP) in Delaware (isolated wetlands 

that may be seasonal). Only CPP greater than 0.25 acre are comprehensively included, 

but some as small as 0.10 acre may also be included. The coding for CPP wetlands, which 

follows a modifi ed National Wetlands Inventory and Cowardin et al. (1979) alpha-numeric 

scheme for a given polygon, includes palustrine forested (PFO), palustrine shrub-scrub 

(PSS), and palustrine emergent (PEM) categories followed by a “2”. Contact staff at the 

Delaware Department of Natural Resources and Environmental Control, Division of 

Water Resources for more information (see http://www.dnrec.state.de.us/water2000/

DWRStaff1.asp for current staff listing). 

APPENDIX C

PROGRAMS TO LOCATE, MAP, MONITOR, AND/OR PROTECT SEASONAL

POOLS IN THE MID-ATLANTIC REGION
78 An Introduction to Mid-Atlantic Seasonal Pools

The Delaware Natural Heritage Program has natural community information about 

some CPP, particularly those in Kent and New Castle counties. A report produced by the 

Delaware Natural Heritage Program helped to determine criteria used to map CPP on the 

state wetland maps (McAvoy and Clancy, 1994).

The Delaware Chapter of The Nature Conservancy (DE TNC) produced a report which 

mapped and assessed the conservation status of Delmarva Bays in Delaware (Zankel and 

Olivero, 1999; copies of the report are available through the DE TNC). DE TNC used a 

more restrictive defi nition for these wetlands than was used at the state level for CPP.

Maryland

There has not been a program undertaken at the state level to locate, map, monitor, 

or protect seasonal pools in Maryland. Wetland geospatial data are available from the 

Maryland Department of Natural Resources at the 1:12,000 scale (MD DNR Geospatial 

Data from 1988-1995, GIS download from http://dnrweb.dnr.state.md.us/gis/data/

data.asp). Wetland geospatial data include all photo-interpretable wetlands greater or equal 

to 0.5 acres (2,023 m2

), although some wetlands less than or equal to 3 acres (12,141 m2) 

obscured by conifers may have been missed. 

Some Nontidal Wetlands of Special State Concern identifi ed by the Maryland Department 

of the Environment and the MD DNR are seasonal pools, especially on the lower coastal 

plain, but they are not indicated as such on the map (Paula Becker and Scott Smith, pers. 

comm.). The state typically only identifi es vernal pools that have state-rare, threatened 

or endangered species in them and these seasonal pools are in the MD DNR Heritage 

Database. 

The Montgomery County Department of Environmental Protection (DEP) and the 

Maryland-National Capital Park & Planning Commission (M-NCPPC) initiated a vernal 

pool mapping program in 2002 to map seasonal pools throughout Montgomery County, 

Maryland as part of the Countywide Stream Protection Strategy. DEP is developing a 

Biological Monitoring Database. 

New Jersey

The New Jersey Department of Environmental Protection’s Endangered and Nongame 

Species Program established the Vernal Pool Survey Project in 2000. The project’s main 

objectives are to locate, map, and inventory seasonal pools statewide. Additionally, this 

initiative will monitor the pools’ amphibian populations utilizing a trained group of 

volunteers. Data collected by volunteers is entered into the Department of Environmental 

Protection’s land use regulatory databases, which are used to guide land use decisions 

(Tesauro, 2004). 

The Center for Remote Sensing and Spatial Analysis (CRSSA) lab at Rutgers University 

is a collaborator in New Jersey’s Vernal Pool Survey Project. CRSSA is utilizing GIS data 

layers (e.g., soils, wetlands, geology) and various maps (e.g., digital elevation models, color 

orthophotography) to fi nd areas where vernal pools are likely to occur. The Center scans 

high-resolution orthophotography of these hotspot areas to pinpoint potential vernal pool 

locations (see www.dbcrssa.edu/ims/vernal for more information).
Appendix C: Programs to Locate, Map, Monitor, and/or Protect Seasonal Pools 79

Seasonal pools that are already certifi ed in New Jersey are mapped (see http://

www.state.nj.us/dep/landuse/fww/vernal/index.html). Volunteers continue to collect 

biological data about seasonal pools in New Jersey using Freshwater Wetlands Vernal 

Habitat Protocols (see Appendix B). Volunteer training sessions are held each year; the 

schedule is posted on their website. 

Pennsylvania

In Pennsylvania, there are multiple ongoing collaborative efforts to learn more about 

seasonal pools and the biota they support. The Pennsylvania Department of Conservation 

and Natural Resources (DCNR) considers “vernal ponds” as “special habitat.” Recently, 

a major program was initiated that will lead to a state-wide seasonal pool locating and 

monitoring program. The Pennsylvania Game Commission awarded a State Wildlife Grant 

to the Western Pennsylvania Conservancy (WPC) (http://www.paconserve.org) to develop a 

web-based seasonal pool registry and research program, beginning in the summer of 2005. 

This registry program will bring together academic institutions, non-profi t organizations, 

state and federal agencies, and citizen volunteers to identify, locate, and study seasonal 

pools in Pennsylvania. This grant was awarded in response to DCNR’s recognition that 

vernal pools are integral to the survival of many at-risk species of wildlife, and that the 

distribution and abundance of seasonal pools are currently unknown in Pennsylvania. 

The Pennsylvania DCNR supports other efforts related to seasonal pool conservation and 

management through its Wildlife Resource Conservation Program (WRCP). In 2002, 

the WRCP collaborated with DCNR’s Bureau of Forestry, The Nature Conservancy, and 

the WPC to fund a study constructing a set of biological criteria that would facilitate the 

classifi cation and management of different types of seasonal pools in Pennsylvania. Other 

research projects include elucidating the population structure of seasonal pool-breeding 

amphibians using molecular genetics techniques and investigating the impacts of timber 

harvesting on woodland amphibians. 

The Upper Susquehanna Coalition (USC), a network of natural resource professionals 

from three counties of Pennsylvania and twelve counties of New York that make up 

the headwaters of the Susquehanna River, has been extremely active in seasonal pool 

conservation. Through funds provided by the U.S. EPA in support of their ephemeral 

wetlands/seasonal pool program, USC is mapping pools throughout the upper 

Susquehanna watershed with the ultimate goal of mapping 940 pools. Additionally, the 

USC developed a seasonal pool assessment form in 2003, which facilitates a major data 

collection effort that began in spring of 2004. The seasonal pool assessment form is a GIS 

user interface that collects and organizes comprehensive information on the surveyed 

vernal pools. Some of this information will be automatically fi lled in according to location 

of data point. Other details recorded by the observer include: pool characteristics, site 

location, directions to the pool, area of the pool, surrounding habitat/land-use, water 

chemistry, vegetation and fauna data. For more information contact USC (http://www.u-sc.org/html/vernalpoolpage.htm).
80 An Introduction to Mid-Atlantic Seasonal Pools

Virginia

There has not been a program undertaken at the state level to locate, map, monitor, or 

protect seasonal pools in Virginia. There have been exhaustive biological inventories of 

several seasonal pool systems, including a detailed description of the Shenandoah sinkhole 

pond system in Virginia (Buhlmann et al., 1999). The Grafton Ponds Sinkhole Complex 

has also been inventoried and mapped (Rawinski, 1997; Roble, 1998; Roble and Stevenson, 

1998), and a comprehensive management plan is in development (Van Alstine et al., 2001). 

West Virginia 

There has not been a program undertaken at the state level to locate, map, monitor, or 

protect seasonal pools in West Virginia. 
Appendix D: Sources of Additional Information on Seasonal Pools 81

APPENDIX D

SOURCES OF ADDITIONAL INFORMATION ON SEASONAL POOLS

Amphibian and Seasonal Pool Field Guides:

Altig, R., R.W. McDiarmid, K.A. Nichols, and P.C. Ustach. 1998. Tadpoles of the United 

States and Canada: A Tutorial and Key. Contemporary Herpetology Information Series 

1998. Available from http://www.pwrc.usgs.gov/tadpole.

Conant, R. and J.T. Collins. 1998. A Field Guide to Reptiles and Amphibians of Eastern 

and Central North America. 3rd Edition, expanded. Houghton Miffl in, Boston.

Green, N.B. and T.K. Pauley. 1987. Amphibians and Reptiles in West Virginia. University 

of Pittsburgh Press, Pittsburgh, Pennsylvania. 

Hulse, A.C., C.J. McCoy, and E.J. Censky. 2001. Amphibians and Reptiles of Pennsylvania 

and the Northeast. Cornell University Press, Ithaca, New York.

Kenney, L.P. and M.R. Burne. 2001. A Field Guide to the Animals of Vernal Pools. 

Massachusetts Division of Fisheries & Wildlife and the Vernal Pool Association, 

Westborough, Massachusetts.

Petranka, J.W. 1998. Salamanders of the United States and Canada. Smithsonian 

Institution Press, Washington, D.C. 

Tyning, T.F. 1990. A Guide to Amphibians and Reptiles. Stokes Nature Guides. Little, 

Brown and Company, Boston.

White, J.F. and A.W. White. 2002. Amphibians and Reptiles of Delmarva. Tidewater 

Publishers, Centreville, Maryland.

Seasonal Pool Publications:

Biebighauser, T.R. 2002. A Guide to Creating Vernal Ponds. USDA Forest Service. 

Available from http://www.fs.fed.us/r8/boone/vernal.pdf.

Calhoun, A.J.K. and M.W. Klemens. 2002. Best development practices: Conserving poolbreeding amphibians in residential and commercial developments in the northeastern 

United States. MCA Technical Paper No. 5, Metropolitan Conservation Alliance. 

Wildlife Conservation Society, Bronx, New York.

Calhoun, A.J.K. and P. deMaynadier. 2004. Forestry habitat guidelines for vernal pool 

wildlife. MCA Technical Paper No. 6, Metropolitan Conservation Alliance. Wildlife 

Conservation Society, Bronx, New York.

Colburn, E.A. 2004. Vernal pools: Natural history and conservation. McDonald & 

Woodward Publishing Company, Blacksburg, Va.

Williams, D.D. 1987. The Ecology of Temporary Waters. Timber Press, Portland, Oregon. 
82 An Introduction to Mid-Atlantic Seasonal Pools

Seasonal Pool Educational Programs:

Roger Tory Peterson Institute. Vernal Pool Project: Teacher professional development and 

classroom pool surveys (http://vernalpools.rtpi.org).

The Vernal Pool Association. Online resources for teachers and students 

(http://www.vernalpool.org).

Vernal Pool Society of Virginia. The Spring Pools Institute: Field courses for adults and 

mature youth; Virginia’s Disappearing Ponds: Traveling educational outreach 

(http://www.lynchburgbiz.com/virginiasvernalpools).

Amphibian Monitoring Programs:

Frogwatch USA, National Wildlife Federation (in partnership with USGS). Long-term, 

volunteer-based frog and toad monitoring program (http://www.nwf.org/frogwatchUSA).

North American Amphibian Monitoring Program, Patuxent Wildlife Research Center, 

USGS. Collaborative, volunteer-based vocal amphibians monitoring program (http://

www.pwrc.usgs.gov/NAAMP).
Glossary 83

GLOSSARY

Acid deposition: Nitric acid or sulfuric acid 

pollution that is deposited in wet forms such as 

rain and sleet or dry forms including particulates 

and gases. Derived from chemical processes that 

transform nitrogen oxides and sulfur dioxide 

emissions from primarily anthropogenic sources 

(e.g., coal burning), although also from natural 

sources (e.g., volcanoes). 

Aestivate: Refers to an animal that becomes 

dormant or torpid during hot summer months.

Amplexus: Copulatory behavior of frogs and toads; 

males clasp female partners from behind to fertilize 

the females’ eggs as they are released. 

Annual pool: Seasonal body of water that dries 

annually in typical years; they have hydroperiods 

from 2 months to 12 months. 

Anthropogenic: Created by humans or as a sideeffect of human activities.

Biodiversity: Shorthand for biological diversity; the 

variety and variability of life, at the genetic, species, 

and ecosystem level.

Biomass: The weight of total living organisms per 

unit of area or of a species’ population per unit of 

area.

Breeding phenology: Reproductive-related 

activities that occur according to season; time frame 

in months when eggs, larvae, and metamorphs of 

amphibians are present at seasonal pools. 

Cloaca: In many vertebrates, the cloaca is the last 

part of the digestive tract which receives feces and 

urogenital products. In certain invertebrates, the 

cloaca is a terminal portion of the digestive tract that 

also serves as respiratory, excretory, or reproductive 

tract.

Coniferous: Refers to trees that bears seeds in 

cones; the wood of these trees is known as softwood.

Crustaceans: Arthropods of the subphylum 

Crustacea; predominantly aquatic; characteristic 

exoskeleton, segmented body, and jointed limbs. 

Examples are crabs, amphipods, and fairy shrimp.

Deciduous: Refers to trees that lose all their leaves 

during cold seasons (e.g., fall and winter in the 

temperate zone).

Desiccation: Dehydration or the process of drying.

Detritus: Dead organic matter as well as 

decomposers such as bacteria and fungi associated 

with the dead organic matter.

Dormant: Refers to resting state when invertebrates 

and vertebrates undergo periods of reduced 

metabolic and respiratory activity.

Dorsal: The upper surface or back of an animal.

Dorsolateral: Pertaining to the back and side of an 

animal. Many species of true frogs have dorsolateral 

ridges, two ridges that begin at the eye and go all or 

partially down the back. Tadpoles of many species 

exhibit dorsolateral eyes, in which the eyes are 

located on the top but to the side of the head.

Endemic: Exclusively native to or confi ned to a 

certain region.

Ephemeral pool: Temporary body of water formed 

by intense periods of precipitation; hydroperiods less 

than two months. 

Evapotranspiration: The combination of 

evaporation and transpiration referring to the total 

water loss from vegetative leaf surfaces and from the 

soil surface.

Facultative species: Organisms that use seasonal 

pools for obtaining food, water, temporary cover, or 

breeding, though they can also successfully breed in 

other habitats.

Habitat: The physical place, environmental 

conditions, and set of resources that a population 

(a group of individuals of the same species that are 

capable of interacting with each other in a localized 

area) utilizes.

Habitat Fragmentation: The process or occurrence 

of the breaking of a larger region of habitat into 

smaller patches of habitat. For example, a highway 

that is constructed through a forest creates forest 

fragmentation; the total area of forest, the size of the 

forest patches, and the connectedness of the forest 

decreases as a consequence. 

Herpetofauna: Grouping of animals that is 

composed of amphibians and reptiles.
84 An Introduction to Mid-Atlantic Seasonal Pools

Hybrid: Progeny of a cross between two 

different species. For example, salamanders with 

chromosomes from both Jefferson and blue-spotted 

salamanders as a result of interbreeding between 

these two species are considered hybrids.

Hydrology: The scientifi c study of water, including 

the occurrence, properties, distribution, circulation 

and transport of water. 

Hydroperiod: The duration of time when a wetland 

or other water body is saturated or covered with 

water.

Impervious: Refers to surfaces that do not allow 

the penetration of water and prevent precipitation 

and other water to infi ltrate soils. Impervious 

materials include asphalt, concrete, brick and stone; 

impervious surfaces include rooftops, parking lots, 

roads, and buildings as well as highly compacted 

soils in urban areas. 

Indicator species: Organisms that depend upon 

seasonal pools for optimal breeding conditions.

Invertebrates: Animals lacking a backbone or 

vertebrae.

Landscape connectivity: The extent to which the 

landscape facilitates wildlife movement. 

Landscape: The traits, patterns, and structure 

of a specifi c geographic area (e.g., mountain 

range, watershed, state), including its biological 

composition, its physical environment, and its 

anthropogenic or social patterns. 

Land use: The way land is developed and used in 

terms of the kinds of anthropogenic activities that 

occur (e.g., agricultural areas, industrial areas).

Larva: The immature stage of any animal species. 

Larvae are typically very different in body form and 

habit from the adults that they metamorphose into.

Life history: The entire progression of changes 

that an organism undergoes from inception or 

conception to death. 

Metamorphosis: The dramatic transformation 

from a larva and/or juvenile form to an adult form; 

occurs in numerous invertebrates (e.g., insects) and 

vertebrates (e.g., amphibians). 

Mole salamander: Of the family Ambystomatidae; 

this family contains 30 species of salamanders, 

seven of which are mid-Atlantic seasonal pool 

indicator species. The common name of Ambystoma 

talpoideum, one of these indicator species, is also 

‘mole salamander.’

Paedomorph: A sexually mature individual 

which fails to metamorphose, retaining its larval 

morphology; literally means “child-shape” or 

“underdeveloped.”

Physiological: Relating to the science of the bodily 

functions or organic processes (e.g., metabolism, 

digestion, reproduction) of an organism. 

Semipermanent pool: Body of water that undergoes 

seasonal fl uctuations in water levels; they do not dry 

annually and have hydroperiods of greater than 12 

months. 

Spermatophore: A packet or “container” of sperm 

produced by male animals, which is subsequently 

taken up by or placed in or on the body of a 

female. Spermatophores are produced by male 

Ambystomatid salamanders.

Succession: The gradual change and replacement 

over time of one group of species in a community by 

other groups or of one set of conditions by another.

Ventral: The under surface or belly of an animal.

Watershed: The area of land from which runoff 

of water, sediments, and dissolved materials (e.g., 

nutrients, contaminants) drain into a river, lake, 

estuary, or ocean. Watersheds can be viewed at 

different scales, from very small (e.g., the area 

draining into a small stream) to very large (e.g., the 

entire Chesapeake Bay watershed of 64,000 square 

miles). 

Wetland: Transitional areas where land-based 

and water-based ecosystems overlap. Wetlands are 

defi ned for regulatory purposes as “those areas that 

are inundated or saturated by surface or ground water 

at a frequency and duration suffi cient to support, 

and that under normal circumstances do support, a 

prevalence of vegetation typically adapted for life in 

saturated soil conditions. Wetlands generally include 

swamps, marshes, bogs, and similar areas.” (This 

defi nition is from the U.S. Army Corps of Engineers 

Wetlands Delineation Manual and 33 Code of 

Federal Regulations 328.3(b)). 

Zooplankton: Small, often microscopic animals 

that feed on detritus, phytoplankton, and other 

zooplankton and are preyed upon by zooplankton 

and other seasonal pool animals.
Literature Cited 85

Albers, P.H. and R.M. Prouty. 1987. Survival of spotted 

salamander eggs in temporary woodland ponds of 

coastal Maryland. Environmental Pollution 46: 45-

61.

Anderson, J.D. and R.V. Giacosie. 1967. Ambystoma 

laterale in New Jersey. Herpetologica 23: 108-111.

Anderson, J.D., D.D. Hassinger, and G.H. Dalrymple. 

1971. Natural mortality of eggs and larvae of 

Ambystoma t. tigrinum. Ecology 52: 1107-1112.

Bachmann, M.D., R.G. Carlton, J.M. Burkholder, and 

R.G. Wetzel. 1986. Symbiosis between salamander 

eggs and green algae: Microelectrode measurements 

inside eggs demonstrate effect of photosynthesis on 

oxygen concentration. Canadian Journal of Zoology 

64: 1586–1588. 

Bader, R.N. and J.C. Mitchell. 1982. Geographic 

distribution: Ambystoma talpoideum. Herpetological 

Review 13: 23. 

Barinaga, M. 1990. Where have all the froggies gone? 

Science 247: 1033-1034.

Beebee, T.J.C. 1996. Ecology and Conservation of 

Amphibians. Chapman & Hall, London.

Belk, D. 1975. Key to the Anostraca (fairy shrimps) of 

North America. Southwestern Naturalist 20: 91-103. 

Belk, D., G. Mura, and S.C. Weeks. 1998. Untangling 

confusion between Eubranchipus vernalis and 

Eubranchipus neglectus (Branchiopoda: Anostraca). 

Journal of Crustacean Biology 18: 147-152.

Berven, K.A. 1988. Factors affecting variation in 

reproductive traits within a population of wood frogs 

(Rana sylvatica). Copeia 1988: 605-615.

Berven, K.A. 1990. Factors affecting population 

fl uctuations in larval and adult stages of the wood 

frog (Rana sylvatica). Ecology 71: 1599-1608.

Berven, K.A. and T.A. Grudzien. 1990. Dispersal in the 

wood frog (Rana sylvatica): Implications for genetic 

population structure. Evolution 44: 2047-2056.

Biebighauser, T.R. 2002. A guide to creating vernal 

ponds. USDA Forest Service. Available from http:

//www.fs.fed.us/r8/boone/vernal.pdf (accessed July 

2004).

Bishop, S.C. 1941. The Salamanders of New York. New 

York State Museum Bulletin 324. The University of 

the State of New York, Albany.

Blaustein, A.R. and J.M. Kieseker. 2002. Complexity 

in conservation: lessons from the global decline of 

amphibian populations. Ecology Letters 5: 597-608.

Blem, C.R. and L.B. Blem. 1989. Tolerance of 

acidity in a Virginia population of the spotted 

salamander, Ambystoma maculatum (Amphibia: 

Ambystomatidae). Brimleyana 15: 37-45.

LITERATURE CITED

Blem, C.R. and L.B. Blem. 1991. Cation concentrations 

and acidity in breeding ponds of the spotted 

salamander, Ambystoma maculatum (Shaw) 

(Amphibia: Ambystomatidae), in Virginia. 

Brimleyana 17: 67-76.

Bogart, J.P. and M.W. Klemens. 1997. Hybrids 

and genetic interactions of mole salamanders 

(Ambystoma jeffersonianum and A. laterale) 

(Amphibia: Caudata) in New York and New England. 

American Museum Novitates 3218. American 

Museum of Natural History, New York City.

Bohonak, A.J. and H.H. Whiteman. 1999. Dispersal 

of the fairy shrimp Branchinecta coloradensis

(Anostraca): Effects of hydroperiod and salamanders. 

Limnology and Oceanography 44: 487-493.

Boone, M.D. and C.M. Bridges. 2003. Effects of 

pesticides on amphibian populations. Pages 152-167 

in R.D. Semlitsch, editor. Amphibian Conservation. 

Smithsonian Institution Press, Washington, D.C.

Brodman, R., J. Ogger, M. Kolaczyk, R.A. Pulver, A.J. 

Long, and T. Bogard. 2003. Mosquito control by 

pond-breeding salamander larvae. Herpetological 

Review 34: 116-119.

Brooks, R.T. 2000. Annual and seasonal variation 

and the effects of hydroperiod on benthic 

macroinvertebrates of seasonal forest (“vernal”) 

ponds in central Massachusetts, USA. Wetlands 20: 

707-715.

Brooks, R.T. 2004. Weather-related effects on woodland 

vernal pool hydrology and hydroperiod. Wetlands 

24: 104-114.

Brooks, R.T. and K.L. Doyle. 2001. Shrew species 

richness and abundance in relation to vernal pond 

habitat in southern New England. Northeastern 

Naturalist 8: 137-148.

Brooks, R.T. and M. Hayashi. 2002. Depth-area-volume 

and hydroperiod relationships of ephemeral (vernal) 

forest pools in southern New England. Wetlands 22: 

247-255.

Buhlmann, K.A. and R.L. Hoffman. 1990. Geographic 

distribution: Ambystoma tigrinum tigrinum. 

Herpetological Review 21: 36.

Buhlmann, K.A. and J.C. Mitchell. 2000. Age of adult 

eastern tiger salamanders (Ambystoma tigrinum 

tigrinum) in a Virginia sinkhole pond complex: 

Implications for conservation. Journal of the Elisha 

Mitchell Science Society 116: 239-244.

Buhlmann, K.A., J.C. Mitchell, and L.R. Smith. 1999. 

Descriptive ecology of the Shenandoah Valley 

sinkhole pond system in Virginia. Banisteria 13: 23-

51.
86 An Introduction to Mid-Atlantic Seasonal Pools

Burne, M.R. 2001. Massachusetts Aerial Photo Survey 

of Potential Vernal Pools. Natural Heritage & 

Endangered Species Program, Massachusetts 

Division of Fisheries & Wildlife, Westborough, 

Massachusetts.

Calhoun, A. 2003. Maine citizen’s guide to locating and 

documenting vernal pools. Maine Audubon Society, 

Falmouth, Maine.

Calhoun, A.J.K. and P. deMaynadier. 2004. Forestry 

habitat guidelines for vernal pool wildlife. MCA 

Technical Paper No. 6, Metropolitan Conservation 

Alliance. Wildlife Conservation Society, Bronx, New 

York.

Calhoun, A.J.K. and M.W. Klemens. 2002. Best 

development practices: Conserving pool-breeding 

amphibians in residential and commercial 

developments in the northeastern United States. 

MCA Technical Paper No. 5, Metropolitan 

Conservation Alliance. Wildlife Conservation 

Society, Bronx, New York.

Calhoun, A.J.K., T.E. Walls, S.S. Stockwell, and M. 

McCollough. 2003. Evaluating vernal pools as a 

basis for conservation strategies: A Maine case study. 

Wetlands 23: 70-81.

Carey, C., A.P. Pessier, and A.D. Peace. 2003. Pathogens, 

infectious disease, and immune defenses. Pages 

127-136 in R.D. Semlitsch, editor. Amphibian 

Conservation. Smithsonian Institution Press, 

Washington, D.C.

Church, S.A., J.M. Kraus, J.C. Mitchell, D.R. Church, 

and D.R. Taylor. 2003. Evidence for multiple 

Pleistocene refugia in the postglacial expansion of 

the eastern tiger salamander, Ambystoma tigrinum 

tigrinum. Evolution 57: 372-383.

Colburn, E.A. 1997. Certifi ed: A citizen’s step-by-step 

guide to protecting vernal pools. MA Audubon 

Society, Lincoln, Ma.

Colburn, E.A. 2004. Vernal Pools: Natural History and 

Conservation. McDonald & Woodward Publishing 

Company, Blacksburg, Virginia.

Conant, R. and J.T. Collins. 1998. A Field Guide to 

Reptiles and Amphibians of Eastern and Central 

North America. 3rd Edition, expanded. Houghton 

Miffl in Company, Boston.

Cook, R.P. 1983. Effects of acid precipitation on 

embryonic mortality of Ambystoma salamanders in 

the Connecticut Valley of Massachusetts. Biological 

Conservation 27: 77-88.

Cooper, J.E. 1955. Notes on the amphibians and reptiles 

of southern Maryland. The Maryland Naturalist 23: 

90-100.

Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 

1979. Classifi cation of Wetlands and Deepwater 

Habitats of the United States. U. S. Department of 

the Interior, Fish and Wildlife Service, Washington, 

D.C. Available from Northern Prairie Wildlife 

Research Center Online, Jamestown, ND, http:

//www.npwrc.usgs.gov/resource/1998/classwet/

classwet.htm (accessed January 2005).

Dahl, T.E. 1990. Wetlands Losses in the United States 

1780s to 1980s. U.S. Department of the Interior, Fish 

and Wildlife Service, Washington, D.C. 

Dahl, T.E. 2000. Status and Trends of Wetlands in 

the Conterminous United States 1986 to 1997. 

U.S. Department of the Interior, Fish and Wildlife 

Service, Washington, D.C. 

deMaynadier, P.G. and M.L. Hunter, Jr. 1999. Forest 

canopy closure and juvenile emigration by poolbreeding amphibians in Maine. Journal of Wildlife 

Management 63: 441-450.

DiMauro, D. and M.L. Hunter, Jr. 2002. Reproduction 

of amphibians in natural and anthropogenic 

temporary pools in managed forests. Forest Science 

48: 397-406.

Dodd, Jr., C.K. and L.L. Smith. 2003. Habitat 

destruction and alteration: Historical trends and 

future prospects for amphibians. Pages 94-112 in 

R.D. Semlitsch, editor. Amphibian Conservation. 

Smithsonian Institution Press, Washington, D.C.

Dodson, S. and D. Frey. 1991. Cladocera and other 

branchiopods. Pages 723-786 in J.H. Thorp and A.P. 

Covich, editors. Ecology and Classifi cation of North 

American Freshwater Invertebrates. Academic Press, 

San Diego.

Ernst, C.H. and R.W. Barbour. 1989. Snakes of Eastern 

North America. George Mason University Press, 

Fairfax, Virginia. 

Ernst, C.H., R.W. Barbour, and J.E. Lovich. 1994. Turtles 

of the United States and Canada. Smithsonian 

Institution Press, Washington, D.C.

Faccio, S.D. 2003. Postbreeding emigration and 

habitat use by Jefferson and spotted salamanders in 

Vermont. Journal of Herpetology 37: 479-489.

Fahrig, L. 2002. Effect of habitat fragmentation on 

the extinction threshold: A synthesis. Ecological 

Applications 12: 346-353. 

Fahrig, L., J.H. Pedlar, S.E. Pope, P.D. Taylor, and J.F. 

Wegner. 1995. Effect of road traffi c on amphibian 

density. Biological Conservation 73: 177-182.

Findlay, C.S. and J. Bourdages. 2000. Response time of 

wetland biodiversity to road construction on adjacent 

lands. Conservation Biology 14: 86-94.
Literature Cited 87

Forman, R.T.T. and L.E. Alexander. 1998. Roads and 

their major ecological effects. Annual Review of 

Ecology and Systematics 29: 207-231.

Forman, R.T.T. and R.D. Deblinger. 2000. The ecological 

road-effect zone of a Massachusetts (U.S.A.) 

suburban highway. Conservation Biology 14: 36-46.

Forman, R.T.T., D. Sperling, J.A. Bissonette, A.P. 

Clevenger, C.D. Cutshall, V.H. Dale, L. Fahrig, R. 

France, C.R. Goldman, K. Heanue, J.A. Jones, F.J. 

Swanson, T. Turrentine, and T.C. Winter. 2003. 

Road Ecology: Science and Solutions. Island Press, 

Washington, D.C.

Gascon, C. and D. Planas. 1986. Spring pond water 

chemistry and the reproduction of the wood frog, 

Rana sylvatica. Canadian Journal of Zoology 64: 543-

550.

Gibbons, J.W. 2003. Terrestrial habitat: A vital 

component for herpetofauna of isolated wetlands. 

Wetlands 23: 630-635.

Gibbons, J.W., V.J. Burke, J.E. Lovich, R.D. Semlitsch, 

T.D. Tuberville, J.R. Bodie, J.L. Greene, P.H. 

Niewiarowski, H.H. Whiteman, D.E. Scott, J.H.K. 

Pechmann, C.R. Harrison, S.H. Bennett, J.D. Krenz, 

M.S. Mills, K.A. Buhlmann, J.R. Lee, R.A. Seigel, 

A.D. Tucker, T.M. Mills, T. Lamb, M.E. Dorcas, J.D. 

Congdon, M.H. Smith, D.H. Nelson, M.B. Dietsch, 

H.G. Hanlin, J.A. Ott, and D.J. Karapatakis. 1997. 

Perceptions of species abundance, distribution, and 

diversity: Lessons from four decades of sampling 

on a government-managed reserve. Environmental 

Management 21: 259-268. 

Gibbs, J.P. 1993. Importance of small wetlands for 

the persistence of local populations of wetlandassociated animals. Wetlands 13: 25-31.

Gibbs, J.P. 1998. Amphibian movements in response to 

forest edges, roads, and streambeds in southern New 

England. Journal of Wildlife Management 62: 584-

589.

Gibbs, J.P. 2000. Wetland loss and biodiversity 

conservation. Conservation Biology 14: 314-317.

Gibbs, J.P. and A.R. Breisch. 2001. Climate warming and 

calling phenology of frogs near Ithaca, New York, 

1900-1999. Conservation Biology 15: 1175-1178.

Gibbs, J.P. and W.G. Shriver. 2005. Can road mortality 

limit population of pool-breeding amphibians? 

Wetlands Ecology and Management 13: 281-289.

Grant, E.H.C. 2005. Correlates of vernal pool 

occurrence in the Massachusetts, USA landscape. 

Wetlands 25: 480-487.

Green, D.E. 2001. Restraint and handling of live 

amphibians. Amphibian Research and Monitoring 

Initiative Standard Operating Procedure, No. 100. 

National Wildlife Health Center. Available from 

http://www.nwhc.usgs.gov/research/amph_dc/sop_

restraint.html (accessed February 2005).

Green, N.B. 1956. The ambystomatid salamanders of 

West Virginia. Proceedings of the West Virginia 

Academy of Science 27: 16-18.

Green, N.B. and P. Brant, Jr. 1966. Salamanders found 

in West Virginia caves. Proceedings of the West 

Virginia Academy of Science 38: 42-45.

Green, N.B. and T.K. Pauley. 1987. Amphibians and 

Reptiles in West Virginia. University of Pittsburgh 

Press, Pittsburgh, Pennsylvania. 

Guerry, A.D. and M.L. Hunter, Jr. 2002. Amphibian 

distributions in a landscape of forests and 

agriculture: An examination of landscape 

composition and confi guration. Conservation 

Biology 16: 745-754.

Hairston, N.G. 1987. Community Ecology and 

Salamander Guilds. Cambridge University Press, 

Cambridge.

Hardy, J.D., Jr. 1969. A summary of recent studies of 

the salamander, Ambystoma mabeei. Solomons, 

Maryland: Chesapeake Biological Laboratory. 

Reference 69-20: 3.

Hardy, J.D., Jr. and J.D. Anderson. 1970. Ambystoma 

mabeei. Catalogue of American Amphibians and 

Reptiles: 81.1-81.2.

Harris, H.S., Jr. 1975. Distributional Survey (Amphibia/

Reptilia): Maryland and the District of Columbia. 

Bulletin Maryland Herpetological Society 11: 73-167.

Harris, R.N. 1980. The consequences of within-year 

timing of breeding in Ambystoma maculatum. 

Copeia 1980: 719–722.

Hassinger, D.D., J.D. Anderson, and G.H. Dalrymple. 

1970. The early life history and ecology of 

Ambystoma tigrinum and Ambystoma opacum in New 

Jersey. American Midland Naturalist 84: 474-495.

Hayslett, M.S. 2003. Natural history of the mole 

salamander Ambystoma talpoideum in Virginia. M.S. 

Thesis, Longwood University, Farmville, Virginia.

Hecnar, S.J. and R.T. M’Closkey. 1997. The effects of 

predatory fi sh on amphibian species richness and 

distribution. Biological Conservation 79: 123-131.

Herrmann, H.L., K.J. Babbitt, M.J. Baber, and R.G. 

Congalton. 2005. Effects of landscape characteristics 

on amphibian distribution in a forest-dominated 

landscape. Biological Conservation 123: 139-149.
88 An Introduction to Mid-Atlantic Seasonal Pools

Hershey, A.E., A.R. Lima, G.J. Niemi, and R.R. Regal. 

1998. Effects of Bacillus thuringiensis israelensis (BTI) 

and methoprene on nontarget macroinvertebrates in 

Minnesota wetlands. Ecological Applications 8: 41-

60.

Hilsenhoff, W. 1991. Diversity classifi cation of insects 

and Collembola. Pages 593-663 in J.H. Thorp and 

A.P. Covich, editors. Ecology and Classifi cation of 

North American Freshwater Invertebrates. Academic 

Press, San Diego.

Homan, R.N., B.S. Windmiller, and J.M. Reed. 2004. 

Critical thresholds associated with habitat loss for 

two vernal pool-breeding amphibians. Ecological 

Applications 14: 1547-1553.

Horne, M.T. and W.A. Dunson. 1995. The interactive 

effects of low pH, toxic metals, and DOC on 

a simulated temporary pond community. 

Environmental Pollution 89: 155-161.

Hulse, A.C., C.J. McCoy, and E.J. Censky. 2001. 

Amphibians and Reptiles of Pennsylvania and the 

Northeast. Cornell University Press, Ithaca, New 

York.

Ireland, P.H. 1989. Larval survivorship in two 

populations of Ambystoma maculatum. Journal of 

Herpetology 23: 209-215.

Jensen, J.R. 2000. Remote Sensing of the Environment: 

An Earth Resource Perspective. Prentice Hall, Upper 

Saddle River, New Jersey.

Jensen, J.B. and C.D. Camp. 2003. Human exploitation 

of amphibians: Direct and indirect impacts. Pages 

199-213 in R.D. Semlitsch, editor. Amphibian 

Conservation. Smithsonian Institution Press, 

Washington, D.C.

Jones, P.H., B.A. Jeffrey, P.K. Walter, and H. Hutchon. 

1992. Environmental impact of road salting. Pages 

1-116 in F.M. D’itri, editor. Chemical Deicers and the 

Environment. Lewis Publishing, Chelsea. 

Jones, B.K., A.C. Neale, M.S. Nash, R.D. Van Remortel, 

J.D. Wickham, K.H. Ritters, and R.V. O’Neill. 2001. 

Predicting nutrient and sediment loadings to streams 

from landscape metrics: a multiple watershed 

study from the United States Mid-Atlantic region. 

Landscape Ecology 16: 301-312.

Jones, A.L. and B.N. Sroka. 1997. Effects of highway 

deicing chemicals on shallow unconsolidated 

aquifers in Ohio. Interim Report, 1988-93. U.S. 

Geological Survey Water Resources Investigations 

Report 97-4027, Columbus, Ohio.

Jung, R.E. and C.H. Jagoe. 1995. Effects of low pH and 

aluminum on body size, swimming performance, 

and susceptibility to predation of green tree frog 

(Hyla cinerea) tadpoles. Canadian Journal of Zoology 

73: 2171-2183.

Kats, L.B., J.W. Petranka, and A. Sih. 1988. Antipredator 

defenses and the persistence of amphibian larvae 

with fi shes. Ecology 69: 1865-1870.

Kenney, L.P. and M.R. Burne. 2001. A Field Guide to the 

Animals of Vernal Pools. Massachusetts Division of 

Fisheries & Wildlife and the Vernal Pool Association, 

Westborough, Massachusetts.

Kiesecker, J.M. 2003. Invasive species as a global 

problem: Toward understanding the worldwide 

decline of amphibians. Pages 113-126 in R.D. 

Semlitsch, editor. Amphibian Conservation. 

Smithsonian Institution Press, Washington, D.C.

Klemens, M.K. 1993. Amphibians and reptiles of 

Connecticut and adjacent regions. State Geological 

and Natural History Survey of Connecticut, Bulletin 

No. 112. Connecticut Department of Environmental 

Protection, Hartford, Connecticut.

Krenz, J.D. and D.E. Scott. 1994. Terrestrial courtship 

affects mating locations in Ambystoma opacum. 

Herpetologica 50: 46-50.

Laan, R. and B. Verboom. 1990. Effects of pool size and 

isolation on amphibian communities. Biological 

Conservation 54: 251-262.

Leeper, D.A. and B.E. Taylor. 1998. Abundance, biomass 

and production of aquatic invertebrates in Rainbow 

Bay, a temporary wetland in South Carolina, USA. 

Archiv für Hydrobiologie 143: 335-362.

Lehtinen, R.M., S.M. Galatowitsch and J.R. Tester. 1999. 

Consequences of habitat loss and fragmentation for 

wetland amphibian assemblages. Wetlands 19: 1-12.

Leibowitz, S.G. 2003. Isolated wetlands and their 

functions: An ecological perspective. Wetlands 23: 

517-531.

Lichko, L.E. and A.J.K. Calhoun. 2003. An evaluation of 

vernal pool creation projects in New England: Project 

documentation from 1991-2000. Environmental 

Management 32: 141-151.

Lowcock, L.A. and R.W. Murphy. 1990. Seed dispersal 

via amphibian vectors: passive transport of burmarigold, Bidens cernua, achenes by migrating 

salamanders, genus Ambystoma. Canadian FieldNaturalist 104: 298-300.

Madison, D.M. 1997. The emigration of radio-implanted 

spotted salamanders, Ambystoma maculatum. 

Journal of Herpetology 31: 542-551.

Mahoney, D.L., M.A. Mort, and B.E. Taylor. 1990. 

Species richness of calanoid copepods, cladocerans 

and other branchiopods in Carolina Bay temporary 

ponds. American Midland Naturalist 123: 244-258. 

Marsh, D.M. and P.C. Trenham. 2001. Metapopulation 

dynamics and amphibian conservation. 

Conservation Biology 15: 40-49. 
Literature Cited 89

Martof, B.S., W.M. Palmer, J.R. Bailey, and J.R. 

Harrison III. 1980. Amphibians and Reptiles of the 

Carolinas and Virginia. The University of North 

Carolina Press, Chapel Hill, North Carolina.

McAvoy, W. and K. Clancy. 1994. Community 

Classifi cation and Mapping Criteria for Interdunal 

Swales and Coastal Plain Pond Wetlands in 

Delaware. Department of Natural Resources and 

Recreation, Division of Water Resources, Dover, 

Delaware.

McCoy, M.W. and A.H. Savitsky. 2004. Feeding 

ecology of larval Ambystoma mabeei (Urodela: 

Ambystomatidae). Southeastern Naturalist 3: 409-

416.

Milam, J.C. and S.M. Melvin. 2001. Density, habitat 

use, movements, and conservation of spotted turtles 

(Clemmys guttata) in Massachusetts. Journal of 

Herpetology 35: 418-427.

Mitchell, J.C. 1994. The Reptiles of Virginia. 

Smithsonian Institution Press, Washington, D.C.

Mitchell, J.C. and S.B. Hedges. 1980. Ambystoma mabeei

Bishop (Caudata: Ambystomatidae): An addition to 

the salamander fauna of Virginia. Brimleyana 3: 119-

121.

Mitchell, J.C. and K.K. Reay. 1999. Atlas of amphibians 

and reptiles in Virginia. Special Publication No. 1, 

Wildlife Diversity Division. Virginia Department of 

Game and Inland Fisheries, Richmond, Virginia. 

Morey, S.R. 1998. Pool duration infl uences age and body 

mass at metamorphosis in the western spadefoot 

toad: Implications for vernal pool conservation. 

Pages 86-91 in C.W. Witham, E.T. Bauder, D. Belk, 

W.R. Ferren, Jr., and R. Ornduff, editors. Ecology, 

Conservation, and Management of Vernal Pool 

Ecosystems – Proceedings from a 1996 Conference. 

California Native Plant Society, Sacramento. 

National Wetlands Inventory (NWI). 2002. National 

Wetlands Inventory: A Strategy for the 21st Century. 

United States Fish and Wildlife Service, Department 

of Interior. Available from http://www.nwi.fws.gov/

Pubs_Reports/NWI121StatFNL.pdf (accessed 

October 2004).

Nolon, J.R. 1998. Can land use law be used to protect 

vernal pools? Pages 33-38 in B. Fellman, editor. Our 

Hidden Wetlands: The Proceedings of a Symposium 

on Vernal Pools in Connecticut 1998. Yale University 

School and the Connecticut Department of 

Environmental Protection.

Nyman, S. 1991. Ecological aspects of syntopic larvae 

of Ambystoma maculatum and the A. lateralejeffersonium complex in two New Jersey ponds. 

Journal of Herpetology 25: 505-509.

Pawlak, E.M. 1998. Remote sensing and vernal pools. 

Pages 20-21 in B. Fellman, editor. Our Hidden 

Wetlands: The Proceedings of a Symposium on 

Vernal Pools in Connecticut 1998. Yale University 

School and the Connecticut Department of 

Environmental Protection.

Pearson, P.G. 1955. Population ecology of the spadefoot 

toad, Scaphiopus h. holbrooki (Harlan). Ecological 

Monographs 25: 233-267.

Pechmann, J.H.K., R.A. Estes, D.E. Scott, and J.W. 

Gibbons. 2001. Amphibian colonization and use of 

ponds created for trial mitigation of wetland loss. 

Wetlands 21: 93-111. 

Pechmann, J.H.K., D.E. Scott, R.D. Semlitsch, J.P. 

Caldwell, L.J. Vitt, and J.W. Gibbons. 1991. Declining 

amphibian populations: The problem of separating 

human impacts from natural fl uctuations. Science 

253: 892-895.

Petranka, J.W. 1998. Salamanders of the United 

States and Canada. Smithsonian Institution Press, 

Washington, D.C. 

Petranka, J.W., M.P. Brannon, M.E. Hopey, and C.K. 

Smith. 1994. Effects of timber harvesting on low 

elevation populations of southern Appalachian 

salamanders. Forest Ecology and Management 67: 

135-147.

Phillips, C.A. 1992. Variation in metamorphosis in 

spotted salamanders Ambystoma maculatum from 

eastern Missouri. American Midland Naturalist 128: 

276-280.

Phillips, P.J. and R.J. Shedlock. 1993. Hydrology and 

chemistry of groundwater and seasonal ponds in the 

Atlantic Coastal Plain in Delaware, USA. Journal of 

Hydrology 141: 157-178.

Pinder, A.W. and S.C. Friet. 1994. Oxygen transport 

in egg masses of the amphibians Rana sylvatica and 

Ambystoma maculatum: Convection, diffusion and 

oxygen production by algae. Journal of Experimental 

Biology 197: 17-30.

Porej, D., M. Micacchion, and T.E. Hetherington. 

2004. Core terrestrial habitat for conservation of 

local populations of salamanders and wood frogs in 

agricultural landscapes. Biological Conservation 120: 

399-409.

Pough, F.H. 1976. Acid precipitation and embryonic 

mortality of spotted salamanders, Ambystoma 

maculatum. Science 192: 68-70.

Pough, F.H., R.M. Andrews, J.E. Cadle, M.L. Crump, 

A.H. Savitzky, and K.D. Wells. 2004. Herpetology, 

3rd Edition. Pearson Education, Upper Saddle River, 

New Jersey. 
90 An Introduction to Mid-Atlantic Seasonal Pools

Preisser, E.L., J.Y. Kefer, J.D. Lawrence, and T.W. Clarke. 

2000. Vernal pool conservation in Connecticut: An 

assessment and recommendations. Environmental 

Management 26: 503-513.

Rawinski, T.J. 1997. Vegetation ecology of the Grafton 

Ponds, York County, Virginia, with notes of 

waterfowl use. Natural Heritage Technical Report 

97-10. Virginia Department of Conservation and 

Recreation, Division of Natural Heritage, Richmond, 

Virginia.

Raymond, L.R. and L.M. Hardy. 1991. Effects of a 

clearcut on a population of the mole salamander, 

Ambystoma talpoideum, in an adjacent unaltered 

forest. Journal of Herpetology 25: 509-512.

Regosin, J.V., B.S. Windmiller, R.N. Homan, and J.M. 

Reed. 2005. Variation in terrestrial habitat use by 

four pool-breeding amphibian species. Journal of 

Wildlife Management, in press. 

Regosin, J.V., B.S. Windmiller, and J.M. Reed. 2003a. 

Infl uence of abundance of small-mammal burrows 

and conspecifi cs on the density and distribution of 

spotted salamanders (Ambystoma maculatum) in 

terrestrial habitats. Canadian Journal of Zoology 81: 

596-605.

Regosin, J.V., B.S. Windmiller, and J.M. Reed. 2003b. 

Terrestrial habitat use and winter densities of the 

wood frog (Rana sylvatica). Journal of Herpetology 

37: 390-394. 

Reh, W. and A. Seitz. 1990. The infl uence of land use on 

the genetic structure of populations of the common 

frog Rana temporia. Biological Conservation 54: 239-

249.

Richmond, N.D. 1947. Life history of Scaphiopus 

holbrookii holbrookii (Harlan). Part I: Larval 

development and behavior. Ecology 28: 53-67.

Roble, S.M. 1998. A zoological inventory of the Grafton 

Ponds sinkhole complex, York County, Virginia. 

Natural Heritage Technical Report 98-3. Virginia 

Department of Conservation and Recreation, 

Division of Natural Heritage, Richmond, Virginia.

Roble, S.M. and D.J. Stevenson. 1998. Records of 

Odonata, fi sh and birds from the Grafton

Ponds sinkhole complex, York County, Virginia. 

Banisteria 12: 3-17.

Rothermel, B.B. 2004. Migratory success of juveniles: 

A potential constraint on connectivity for pondbreeding amphibians. Ecological Applications 14: 

1535-1546.

Rothermel, B.B. and R.D. Semlitsch. 2002. An 

experimental investigation of landscape resistance of 

forest versus old-fi eld habitats to emigrating juvenile 

amphibians. Conservation Biology 16: 1324-1332.

Rowe, C.L. and W.A. Dunson. 1993. Relationships 

among abiotic parameters and breeding effort by 

three amphibians in temporary wetlands of central 

Pennsylvania. Wetlands 13: 237-246.

Rowe, C.L., W.J. Sadinski, and W.A. Dunson. 1994. 

Predation on larval and embryonic amphibians by 

acid-tolerant caddisfl y larvae (Ptilostomis postica). 

Journal of Herpetology 28: 357-364.

Sadinski, W.J. and W.A. Dunson. 1992. A multilevel 

study of effects of low pH on amphibians of 

temporary ponds. Journal of Herpetology 26: 413-

422.

Schueler, T.R. 1994. The importance of imperviousness. 

Watershed Protection Techniques 1: 100-111. 

Schwartz, V. and D.M. Golden. 2002. Field Guide to 

Reptiles and Amphibians of New Jersey. New Jersey 

Division of Fish and Wildlife, Westfi eld, New Jersey.

Scott, D.E. 1994. The effect of larval density on adult 

demographic traits in Ambystoma opacum. Ecology 

75: 1383-1396.

Seale, D.B. 1982. Physical factors infl uencing oviposition 

by the wood frog, Rana sylvatica, in Pennsylvania. 

Copeia 1982: 627-635.

Semlitsch, R.D. 1981. Terrestrial activity and summer 

home range of the mole salamander (Ambystoma 

talpoideum). Canadian Journal of Zoology 59: 315-

322. 

Semlitsch, R.D. 1983. Structure and dynamics of two 

breeding populations of the eastern tiger salamander, 

Ambystoma tigrinum. Copeia 1983: 608-616.

Semlitsch, R.D. 1985a. Analysis of climatic factors 

infl uencing migrations of the salamander Ambystoma 

talpoideum. Copeia 1985: 477-489.

Semlitsch, R.D. 1985b. Reproductive strategy of a 

facultatively paedomorphic salamander Ambystoma 

talpoideum. Oecologia 65: 305-313.

Semlitsch, R.D. 1998. Biological delineation of 

terrestrial buffer zones for pond-breeding 

salamanders. Conservation Biology 12: 1113-1119.

Semlitsch, R.D. 2000. Principles for management of 

aquatic-breeding amphibians. Journal of Wildlife 

Management 64: 615-631. 

Semlitsch, R.D. 2003. Conservation of pond-breeding 

amphibians. Pages 8-23 in R.D. Semlitsch, editor. 

Amphibian Conservation. Smithsonian Institution 

Press, Washington, D.C. 

Semlitsch, R.D. and J.R. Bodie. 1998. Are small, isolated 

wetlands expendable? Conservation Biology 12: 

1129-1133.

Semlitsch, R.D. and J.P. Caldwell. 1982. Effects of 

density on growth, metamorphosis, and survivorship 

in tadpoles of Scaphiopus holbrookii. Ecology 63: 905-

911.
Literature Cited 91

Semlitsch, R.D., D.E. Scott, and J.H.K. Pechmann. 1988. 

Time and size at metamorphosis related to adult 

fi tness in Ambystoma talpoideum. Ecology 69: 184-

192.

Semlitsch, R.D., D.E. Scott, J.H.K. Pechmann, and 

J.W. Gibbons. 1996. Structure and dynamics of an 

amphibian community: Evidence from a 16-year 

study of a natural pond. Pages 217-248 in M.L. Cody 

and J.A. Smallwood, editors. Long-term Studies of 

Vertebrate Communities. Academic Press, San Diego.

Shoop, C.R. 1960. The breeding habits of the mole 

salamander, Ambystoma talpoideum (Holbrook), in 

southeastern Louisiana. Tulane Studies in Zoology 8: 

65-82.

Shoop, C.R. 1968. Migratory orientation of Ambystoma 

maculatum: Movements near breeding pools and 

displacements of migrating individuals. Biological 

Bulletin 135: 230-238.

Shoop, C.R. 1974. Yearly variation in larval survival of 

Ambystoma maculatum. Ecology 55: 440-444.

Simovich, M.A. 1998. Crustacean biodiversity and 

endemism in California’s ephemeral wetlands. 

Pages 107-118 in C.W. Witham, E.T. Bauder, D. Belk, 

W.R. Ferren, Jr., and R. Ornduff, editors. Ecology, 

Conservation, and Management of Vernal Pool 

Ecosystems – Proceedings from a 1996 Conference. 

California Native Plant Society, Sacramento. 

Sipple, W.S. 1999. Days Afi eld: Exploring Wetlands in 

the Chesapeake Bay Region. Self-published. Gateway 

Press, Baltimore. 

Skelly, D.K. 1997. Tadpole communities. American 

Scientist 85: 36-45.

Smith, D.G. 2001. Pennak’s Freshwater Invertebrates of 

the United States: Porifera to Crustacea, 4th Edition. 

John Wiley & Sons, New York City. 

Smith, I.M. and D.R. Cook. 1991. Water mites. Pages 

723-786 in J.H. Thorp and A.P. Covich, editors. 

Ecology and Classifi cation of North American 

Freshwater Invertebrates. Academic Press, San Diego.

Sonoda, K., J.A. Yeakley, and C.E. Walker. 2001. Nearstream landuse effects on streamwater nutrient 

distribution in an urbanizing watershed. Journal of 

the American Water Resources Association 37: 1517-

1532. 

Stenhouse, S.L. 1985. Migratory orientation and homing 

in Ambystoma maculatum and Ambystoma opacum. 

Copeia 1985: 631-637.

Stine, C.J., Jr., J.A. Fowler, and R.S. Simmons. 1954. 

Occurrence of the eastern tiger salamander, 

Ambystoma tigrinum tigrinum (Green) in Maryland, 

with notes on its life history. Annals of the Carnegie 

Museum 33: 145-148. 

Stolt, M.H. and M.C. Rabenhorst. 1987. Carolina bays 

on the eastern shore of Maryland: II. Distribution 

and origin. Soil Science Society of America Journal

51: 399-405.

Stone, J.C. 1992. Vernal pools in Massachusetts: 

Aerial photographic identifi cation, biological and 

physiographic characteristics, and state certifi cation 

criteria. M.S. Thesis, University of Massachussetts, 

Amherst, Massachusetts.

Storey, K.B. and J.M. Storey. 1986. Freeze tolerance 

and intolerance as strategies of winter survival in 

terrestrially-hibernating amphibians. Comparative 

Biochemistry and Physiology Part A: Physiology 83: 

613-617.

Storez, R.A. 1969. Observations on the courtship of 

Ambystoma laterale. Journal of Herpetology 3: 87-95.

Stout, B.M., III, K.K. Stout, and C.W. Stihler. 1992. 

Predation by the caddisfl y Banksiola dossuaria on 

egg masses of the spotted salamander Ambystoma 

maculatum. American Midland Naturalist 127: 368-

372.

Stuart, S.N., J.S. Chanson, N.A. Cox, B.E. Young, 

A.S.L. Rodrigues, D.L. Fischman, and R.W. Waller. 

2004. Status and trends of amphibian declines and 

extinctions worldwide. Science 306: 1783-1786.

Tappan, A. 1997. Identifi cation and Documentation of 

Vernal Pools in New Hampshire. New Hampshire 

Fish and Game Department, Nongame and 

Endangered Wildlife Program, Concord, New 

Hampshire.

Templeton, N.S. and H. Laufer. 1983. The effects of a 

juvenile hormone analog (Altosid ZR-515) on the 

reproduction and development of Daphnia magna

(Crustacea: Cladocera). International Journal of 

Invertebrate Reproduction 6: 99-110.

Tesauro, J. 2004. New Jersey’s Vernal Pools. New 

Jersey Division of Fish & Wildlife, Endangered 

and Nongame Species Program. Available from 

http://www.njfi shandwildlife.com/ensp/pdf/

vernalpool03.pdf (accessed August 2004).

Therres, G.D. 1999. Wildlife species of regional 

conservation concern in the northeastern United 

States. Northeast Wildlife 54: 93-100.

Thompson, E.L., J.E. Gates, and G.J. Taylor. 1980. 

Distribution and breeding habitat selection of the 

Jefferson salamander, Ambystoma jeffersonianum, in 

Maryland. Journal of Herpetology 14: 113-120.

Thorp, J.H. and A.P. Covich, editors. 1991. Ecology 

and Classifi cation of North American Freshwater 

Invertebrates. Academic Press, San Diego.
92 An Introduction to Mid-Atlantic Seasonal Pools

Tiner, R.W., Jr. 1990. Use of high-altitude aerial 

photography for inventorying forested wetlands in 

the United States. Forest Ecology and Management 

33/34: 593-604.

Tiner, R.W. 2003a. Estimated extent of geographically 

isolated wetlands in selected areas of the United 

States. Wetlands 23: 636-652.

Tiner, R.W. 2003b. Geographically isolated wetlands of 

the United States. Wetlands 23: 494-516.

Tiner, R.W. and D.G. Burke. 1995. Wetlands of 

Maryland. U.S. Fish and Wildlife Service, National 

Wetlands Inventory, Hadley, Massachusetts and 

Maryland Department of Natural Resources, 

Annapolis, Maryland. 

Turtle, S.L. 2000. Embryonic survivorship of the spotted 

salamander (Ambystoma maculatum) in roadside 

and woodland vernal pools in southeastern New 

Hampshire. Journal of Herpetology 34: 60-67.

Tyndall, R.W. 2001. Vegetation change during a 

thirteen-year period (1987 – 1999) in a Carolina bay 

on the Delmarva Peninsula of Maryland. Castanea 

66: 245-252.

Tyning, T.F. 1990. A Guide to Amphibians and Reptiles. 

Stokes Nature Guides. Little, Brown and Company, 

Boston.

U.S. Environmental Protection Agency (U.S. EPA). 2001. 

How will climate change affect the mid-Atlantic 

region? EPA 903-F-00-002. Region 3. Available from 

http://www.epa.gov/maia/html/globwarm.html 

(accessed February 2005).

Van Alstine, N.E., A.C. Chazal, and K.M. McCoy. 2001. 

A biological survey of the coastal plain depression 

ponds (sinkholes) of Colonial National Historical 

Park, Yorktown, Virginia. Natural Heritage Technical 

Report 01-9. Virginia Department of Conservation 

and Recreation, Division of Natural Heritage, 

Richmond, Virginia.

Walls, S.C. and A.R. Blaustein. 1995. Larval marbled 

salamanders, Ambystoma opacum, eat their kin. 

Animal Behaviour 50: 537-545.

Wernick, B.G., K.E. Cook, and H. Schreier. 1998. 

Land use and streamwater nitrate-N dynamics in 

an urban-rural fringe watershed. Journal of the 

American Water Resources Association 34: 639-650.

Whigham, D.F. and T.E. Jordan. 2003. Isolated wetlands 

and water quality. Wetlands 23: 541-549. 

White, J.F. and A.W. White. 2002. Amphibians and 

Reptiles of Delmarva. Tidewater Publishers, 

Centreville, Maryland.

Wiggins, G.B., R.J. Mackay, and I.M. Smith. 1980. 

Evolutionary and ecological strategies of animals in 

annual temporary pools. Archiv für Hydrobiologie 

Supplement 58: 97-206. 

Wilbur, H.M. 1977. Propagule size, number, and 

dispersion pattern in Ambystoma and Asclepias. 

American Naturalist 111: 43-68.

Wilbur, H.M. 1980. Complex life cycles. Annual Review 

of Ecology and Systematics 11: 67-93.

Wilbur, H.M. and J.P. Collins. 1973. Ecological aspects 

of amphibian metamorphosis. Science 182: 1305-

1314.

Williams, D.D. 1987. The Ecology of Temporary Waters. 

Timber Press, Portland, Oregon. 

Windmiller, B. 1996. The pond, the forest, and the 

city: Spotted salamander ecology and conservation 

in a human-dominated landscape. Ph.D. 

Dissertation, Biology, Tufts University, Medford, 

MA. Available from http://www.hylaecological.com/

publications.html (accessed January 2005).

Windmiller, B., R.N. Homan, J.V. Regosin, L.A. Willitts, 

D.L. Wells, and J.M. Reed. 2006. Two case studies 

of declines in vernal pool-breeding amphibian 

populations following loss of adjacent upland forest 

habitat. Herpetological Conservation 3, in press.

Winfi eld, T.P., T. Cass, and K.B. MacDonald. 1981. 

Small mammal utilization of vernal ponds, San 

Diego County, California. Vernal Ponds and 

Intermittent Streams. University of California, 

Institute of Ecology Publication 28: 161-167.

Winter, T.C. and J.W. LaBaugh. 2003. Hydrologic 

considerations in defi ning isolated wetlands. 

Wetlands 23: 532-540.

Wood, J.T. and R.H. Wilkinson. 1952. Observations on 

the egg masses of spotted salamanders, Ambystoma 

maculatum (Shaw), in the Williamsburg area. The 

Virginia Journal of Science 3: 68-70.

Woodward, B.D. 1982. Local interpopulational variation 

in clutch parameters in the spotted salamander 

(Ambystoma maculatum). Copeia 1982: 157-160.

Wyman, R.L. 1990. What’s happening to the 

amphibians? Conservation Biology 4: 350-352.

Zankel, M. and A. Olivero. 1999. Mapping and Assessing 

the Conservation Status of Delmarva Bay Wetlands 

in Delaware. Final Report, The Nature Conservancy. 

Zedler, P.H. 2003. Vernal pools and the concept of 

“isolated wetlands.” Wetlands 23: 597-607.
United States 

Environmental Protection AgencyOffi ce of Research  and DevelopmentFort Meade, MD 20755-5350Offi cial BusinessPenalty for Private Use$300EPA/903/B-05/001June 2005

PRESORTED STANDARD

POSTAGE & FEES PAID

EPA

PERMIT No. G-35

Please make all necessary changes on the below label,detach or copy, and return to the address in the upper left-hand corner.If you do not wish to receive these reports, CHECK HERE ;detach, or copy this cover, and return to the address in the upper left-hand corner.

EPA/903/B-05/001 An Introduction to Mid-Atlantic Seasonal Pools