FWS/ OBS- 8 2/ 10 .74

SEPTEMBER 1984

HABITAT SUITABILITY INDEX MODELS:

LARVAL AND JUVENILE RED DRUM

SK and Wildlife Service

361

. Department of the Interior
This model is designed to be used by the Division of Ecological Services in

conjunction with the Habitat Evaluation Procedures.
MODEL EVALUATION FORM

Habitat models are designed for a wide variety of ;:>lanning applications

where habitat infonnation is an important consideration in the decision

process. It is impossible, however, to develop a model that performs equally

well in all situations. Each model is published individually to facilitate

updating and reprinting as new inforcnation becomes available. Assistance from

users and resea rchers is an important part of the model improvement process.

Please complete this fonn following appl ice t t on or review of the mode l , Feel

free to include additional information that may be of use to either a model

developer or model user. l4e also would appreciate information on model

testing, modification, and application, as well as copies of modified models or

test results. Please return this form to:

National Coastal Ecosystems Team

U.S. Fish and Wildlife Service

1010 Gause Boulevard

Sl ide11, LA 70458

Thank you for your assistance.

Species _ Geographi c

Location-----------------------------------------

Habitat or Cover Type(s)------------------------------------------------

Type of Application: Impact Analysis Management Action Analysis Basel ine Other -- ------

Variables Measured or Evaluated

._------------------------------

Was the species information useful and accurate? Yes No

If not, what corrections or improvements are needed?--------------
Were the variables and curves clearly defined dnc1 useFul? Yes _

If not, how were or could they be improved?

No

'vlere the techniques suggested for

Appropriate? Yes

Clearly defined? Yes----

Easily applied? Yes----

collection

No

No--

No

of field data:

If not, what other data collection techniques are needed?-----------

Were the model equations logical?

Appropriate?

Yes No

Yes-- No

How were or could they be improved?------------------

Other suggestions for modification or improvement (attach curves, equations,

qraphs , or other appropriate information) _

Additional references or t nfo rma t ion that should be included in the model:

Model Evaluator or Reviewer Date ----------- ---------- Agency • _

Address--------------------------------

Telephone Number Comm:--------- FTS--------------
RIS/08S-82/10.74

September 1984

HABITAT SUITABILITY INDEX MODELS:

LARVAL AND JUVENILE RED DRU~

by

Jack 3uckl ey ~1assachusetts Cooperative Fishery Research Unit

U.S. Fish and Wildlife Service

Department of Forestry and Wildlife Management

Uni vers i ty of i4assachus(~tts

Anherst, ~~ 01003

Project Officers

Rebecca Howard

Norman Benson

National Coastal Ecosystems Team

U.S. Fish and Wildlife Service

1010 Gause Bou1evard

Slidell, LA 70458

Performed for

National Coastal Ecosystems Team

Division of Biological Services

Research and Deve1opment

Fish and Wild1ife Service

U.S. Department of the Interior

Washington, DC 20240
This report should be cited as:

Buckley, J. 1984. Habitat suitability index models:

drum. U.S. Fish Wildl. Servo FWS/OBS-82/10.74.

larval and juvenile red

15 pp.
PREFACE

The habitat suitabil ity index (HSI) model for larval and juvenile red

drum is intended for use in the habitat evaluation procedures (HEP) developed

by the U.S. Fish and Wildlife Service (1980) for impact assessment and habitat

management. The model was developed from a review and synthesis of existing

information and is scaled to produce an index of habitat suitability between 0

(unsuitable habi tat) and 1 (optimal habi tat). Assumptions used to transform

nabt tat use information into the HSI model and guidel ines for model appl ication are described.

This model is a hypothesis of species-habitat relations, not a statement

of proven cause and effect. The relations are the best that can be derived

from the limited information available, and the model has not been fieldtested. For these reasons, the U.S. Fish and Wildl ife Service encourages

users of the model to convey comments, suggestions, and new information that

may hel p increase the util ity and effect i veness of this approach to red drum

habitat evaluation. Please send any comments or suggestions to:

National Coastal Ecosystems Team

U.S. Fish and Wildlife Service

1010 Gause Boulevard

Slidell, LA 70458

iii

CONTENTS

PREF ACE • • • • AC KNOWLEDGf4EIHS . . . . . iii

vi

INTRODUCTION • • • • Distribution • • • • Life History Overview ••••••• SPECIFIC HABITAT REQUIREMENTS ••••••••••• Adul t/Spawni ng ••••• ••••••••• • Eg 9 • • • • • • • • • • • • • • • •

La rva • • . . . • • • . • • • • . . . • • • • • • .

Juveni1e . . . . • •• • • • • • . • • • • . . • •

HABITAT SUITABILITY INDEX (HSI) MODEL. • •••• Model Applicability and Verification Level •••• Model Description ••••••••••••••••• Suitability Index (SI) Graphs for Habitat Variables •• Component Index and Habitat Suitability Index Equations ••••••• Field Use of Models. • • • • • • • • • • ••••• Interpreting Model Outputs •••• • ••••

REFERENCES • • • • • • • • • •

v

. . . . . . . . . . .

1

1

1

2

2

3

3

3

4

4

4

5

9

11

12

13
ACKNOWLEDGt·1ENTS

Development of the habitat suitability index model and narrative for

larval and juvenile red drum was monitored and reviewed by Gary Matlock, Texas

Parks and Wildlife Department, Austin; and J.Y. Christmas and Dr. Robin

Overstreet, Gulf Coast Research Laboratory, Ocean Springs, Mississippi. Model

structure and functional relations were evaluated by personnel of the U.S.

Fish and Wildlife Service's (FWS) National Coastal Ecosystems Team. The

Service's Regional personnel reviewed the model and report. The FWS funded

model development and report publication. Patrick Lynch illustrated the

cover.

vi
RED DRU~ (SciaenoDs ___~-'-J- ocellatus)

INTRODUCTION

Distribution

The red drum is an estuarine-dependent species found along the Atlantic

coast and in the Gulf of Mexico (Hildebrand and Schroeder 1928). Other common

names for this species include redfish and channel bass. Abundance decreases

with increase in latitude along the east coast, and the species is rare north

of New Jersey. There have been 1imited successful freshwater introductions

(S'imnons and Breuer 1962). Relative abundance, as indicated by commercial

landings, is greater in the Gulf of i1exico than along the Atlantic coast

(Yokel 1966).

Red drum support an important sport and commercial fishery along the gulf

coast and, to a lesser extent, along the south Atlantic coast (r1atlock 1980).

The estimated catch by sport fisherman in 1979 was 236,000 kg (520,000 l b)

along the south Atlantic coast and 1,633,000 kg (3,593,000 l b) in the Gulf of ~1exico (U.S. Department of Commerce 1981).

Life History Overview

Spawning of red drum generally begins in early fall and lasts into early

winter, the time depending on location. Along the middle and south Atlantic,

spawning begins in mid-August and extends to late September (Mansueti 1960).

In the Gulf of r~exico, red drum spawn from the end of September through midNovember but primarily in October (Pearson 1929). Along the gulf coast,

spawning takes place in nearshore waters adjacent to channels and passes

(Pearson 1929). There is no specific information on the location of spawning

on the Atlantic coast, although collections of larvae indicate that spawning

is in habitats similar to those on the gulf coast (Mansueti 1960).

Females produce 0.5 to 3.5 million eggs, depending on size and age (Pearson 1929). Eggs are buoyant, clear, and spherical; mean diameter is 0.93 mm

(range 0.86-0.98 mm) (Holt et al. 1981b).

The period from hatching to arrival in a shallow estuarine area is critical for red drum. The mechanism of transport and larval activity appears to

differ between populations of the drowned river valley estuaries on the

Atlantic coast and those of the barrier beach estuaries in the Gulf of Mexico.

Mansueti (1960) postulated that eggs and larvae are transported by deep subsurface currents of hi gh-dens ity water into the Chesapeake Bay. Along the

gulf coast, tidal currents transport the newly hatched larvae into bays
(Pearson 1929). La rvae sometimes swim act ively duri ng transport along the

gulf coast, whereas they are pass i ve duri ng transport in the Chesapeake Bay

(Yokel 1966). Environmental conditions adversely affecting transport can have

a significant impact on an estuarine-dependent species (Nelson et ale 1977).

Larvae transform to the juvenile stage at about 40 mm (1.5 inches) total

1ength (TL) (Simmons and Breuer 1962). Growth is rapi d duri ng the fi rs t 2

years; the fish reach 21.5 em (8.5 inches) Tl in 6 monthst 34 cm (13.5 inches)

in 1 year , and 53-60 em (21-23.6 inches) in 2 years (Pearson 1929). Growth

rate varies qreatly , depending Of) year and location. Average monthly growth

rates were 18.8 mm (0.8 inches) in Louisiana (Bass and Avault 1975), and 28.0

mm (l inch) in Texas (Simmons and Breuer 1962). Red drum reached 9.5 I<.g (21

lb) in 6 years when isolated in a saltwater impoundment (Theiling and Loyacano

1976). Recruitment to the fishery begins after the first year at a total

length of about 30 cm or 12 inches (Yokel 1966).

Female red drum mature at 4 or 5 years of age and males at 3 (Pearson

1929). Length at maturity ranges between 35 and 75 cm (13.75 and 29.5 inches)

TL and varies with location; males mature at a smaller size than females

(Perret et al. 1980). The maxi~um length of adult red drum probably does not

exceed 160 cm (63 inches) TL (Welsh and Breder 1924). Adult red drum are most

frequently found in nearshore marine waters, where they travel in large

schools. Fish occasionally move far offshore, but there is no specific information available on timing, duration, or extent of these movements. Some

adults move into bays in spring, but after their first spawning, red drum

spend less time in the estuary (Yokel 1966). During spring and summer, small

adults that have entered estuaries and large juveniles are found along the

marsh perimeter in water less than 2 m (6.5 ft) deep (Benson 1982). In Texas

and Florida, tagged fish showed little interbay or bay-to-gulf movement,

suggesting that local ized populations inhabit each bay (Simmons and Breuer

1962). In contrast, a tagging study in Mississippi indicated that large

adults mi grated extensi vely (Overstreet 1983). Along the Atl anti c coast,

Welsh and Breder (1924) described a northward migration of fish from southern

waters to the coast of New Jersey.

SPECIFIC HABITAT REQUIREMENTS

Adult/Spawning

Adults are euryhaline, but Simmons and Breuer (1962) found them to be

most abundant at salinities of 30-55 parts per thousand (ppt). They reported

that the species had been successfully transplanted into freshwater. Adults

are also eurythermal, having been observed in water from 2° to 33° C (35.6° to

91. 5° F) (Simmons and Breuer 1962). Drasti c envi ronrnenta1 changes, parti cularly a rapid reduction in water temperature, can cause mortalities (Gunter

1941; Gunter and Hildebrand 1951). The rate of temperature change is more

important than the lowest temperature reached.

In 1aboratory studi es , temperature appeared to be criti ca1 to spawni ng

success. Holt et ale (l981a) found that red drum spawned at temperatures of

2
22°_30° C (71.5°-86° F); optimal temperatures were 22°_25° C (71.5°-77° F).

They postulated that an early reduction in nearshore water temperature could

adversely affect year-class strength.

Salinity is an important factor in hatching success. Red drum eggs float

at salinities greater than 25 ppt and sink at lower salinities (Holt et ale

1981a). Sinking could lead to clumping, respiratory stress, and increased

mortality. A reduction in nearshore salinity immediately after spawning could

severely reduce hatching success. The temperature and sal inity for hatching

were optimal at 25° C (77° F) and 30 ppt, and poorest at 30° C (86° F) and 15

ppt (Holt et ale 1981a). Eggs hatch 28-29 h after fertilization at 23°_24° C

(73°_75° F) (Holt et ale 1981b).

Larva

Red drum larvae occupy either vegetated or unvegetated bottoms in estuaries. In Texas, larvae rest among submerged aquatic vegetation in shal l ow

areas with muddy bottoms until they begin swimming actively (Miles 1950).

Vegetation provides protection from predation and tidal displacement (Miles

1950; Hol t et ale 1983). Red drum larvae are associated with shoal grass

(Ha1odul e wri ghti i) and widgeongrass (~ maritima) in Texas and South

Carol ina (Miles 1951; Hol t et ale 1983). Louisiana has many shallow, quiet

bays «3 m [9.8 ft] deep) with little or no submerged vegetation that serve as

nurseries for larval and juvenile red drum (Bass and Avault 1975; Dr. Will i am

Herke, Louisiana State University, Baton Rouge, unpublished data from Sabine

National Wildl ife Refuge). These areas are typically fringed with marsh, have

1ittl e current, have soft or hard bottom, are turbi d , and are connected with

es tuari es ,

Both temperature and sal inity are important during the first 24 h after

hatching; Holt et ale 1981a reported that the optimum conditions for 24-h

survival were 25° C (77° F) and 30 ppt , Salinity did not affect growth and,

though important in hatching and 24-h survival, was not a factor in survival

at 2 weeks. Temperature becomes a more important factor as 1arvae develop.

Holt et ale (l981a) found that temperatures below 25° C (77° F) resulted in

reduced larval survival at 2 weeks. Temperature had a pronounced effect on

larval growth rate; growth was much faster at 25° or 30° C (77° or 86° F) than

at lower temperatures. At water temperatures below 20° C (68° F), Holt

et ale (l981a) suggested, red drum may be unable to make the transition to

active feeding--a critical period in fish development (May 1974; Vladimirov

1974). (Larval red drum feed on copepods and copepod naapl i i [Boothby and

Avault 1971]).

Juvenil e

For the first year, juveniles live in protected water with little wave

action; in Texas they avoid current and prefer grassy clumps or muddy bottoms

(Simmons and Breuer 1962). In Louisiana estuaries, where submerged vegetation

is uncommon, the fish use shallow, unvegetated, quiet bays (Bass and Avaul t

3
1975). At the end of the fi rs t year, they move into deeper bays or mari ne

littoral areas during cold weather (Pearson 1929); in spring, they move back

into the estuary. While in the estuary, older juveniles are found along or in

marshes at depths less than 2 m (6.5 ft). Progressively more time is spent in

marine areas as red drum mature (Yokel 1966).

Young red drum are both euryhaline and eurythermal. They have been found

at salinities of 0 to 50 ppt and water temperatures of 13° to 28° C (55.4° to

82.4° F) (Perret et al , 1980). Red drum can acclimate to freshwater in 3 h

(Lasswell 1977). Rapid decl ines in water temperature can cause nor-tal ity

(Gunter 1941).

Juvenile red drum between 40 and 50 mm TL (1.5 and 2 inches) feed on

mysid shrimp and amphipods; thereafter penaeid shrimp, blue crabs (Callinectes

sapidus), and fish are the major foods (Bass and Avault 1975). Adult red drum

are usually indiscriminate predators, feeding on shrimp, crabs, and fish

(Boothby and Avault 1971; Overstreet and Heard 1978).

HABITAT SUITABILITY INDEX (HSI) MODEL

Model Applicability and Verification Level

This habitat suitabil ity index model is designed for use throughout the

red drum's range. It is applicable in the estuarine subtidal habitat classes

of Cowardin et al . (1979). The model does not address marine habitat use. It

can be appl i ed to assess habitat sui tabil ity for the 1arval or juvenil e 1ife

stage or both. Because adults are highly mobile and tolerate a wide range of

environmental conditions, no model was developed for this life stage. Since

habitat variables have been derived from research on Gulf of Mexico populations of red drum, the model should be applied only with caution in Atlantic

coast habitats. Although general relations would be the same, some modification of habitat variables may be necessary. The model is intended for yearround use, but some habitat variables apply only to the season when specific

life stages are present.

The HSI models produce an index from 0 to 1.0, which is assumed to be

related to the abilHy of specific habitats to support a population of red

drum. An index value of 1.0 represents optimal habitat and decreasing values

represent less suitable habitat. The models were reviewed by Gary Matlock,

Texas Parks and Wildlife Department, Austin, and by J. Y. Christmas and Dr.

Robin Overstreet, Gulf Coast Research Laboratory, Ocean Springs, Mississippi.

Although their suggestions were incorporated when feasible, the author is

responsible for the final versions of the models. The models have not been

field tested.

Model Description

Two models were developed for larval and juvenile red drum; one is

designed for use in estuaries with naturally vegetated substrates and the

other for use in estuaries that cannot support bottom vegetation because of

4
natural factors such as high turbidity. Water quality, food, and cover life

requisites are included in the models. The habitat variables, either individually or in combination, define the life requisite. The relations among life

requisites, habitat variables, and the HSI are shown in Figure 1.

Water qual ity. Water qual ity affects habitat suitabil ity in both models

and is defined by water temperature and salinity during the larval development

period. It is assumed that a mean temperature below 15° C (59° F) is unsuitable for larval red drum and that 25°_30° C (77°_86° F) is optimal (Vd. t~ean

salinity levels bel ow 10 ppt are unsuitable, and optimal salinity conditions

are assumed to be 25-30 ppt (V 2 ) . Although VI and V2 are important only to

larvae (since the juveniles tolerate a wide temperature and salinity range),

larval and juvenile life stages are combined to calculate the estuarine HSI.

Food and cover. In both models, it is assumed that food availability is

a function of estuarine productivity and that the amount of intertidal wetlands is related to productivity. Although the optinum ratios of wet l and to

open water are unknown, it is assumed that red drum food abundance increases

as the percentage of open water edge fringed with intertidal wetlands

increases (V 3 ) . Intertidal wetland is defined for these models as an estuarine area vegetated with persistent emergent species such as Spartina spp.

and Juncus spp , Estuaries in the eastern gulf, along the middle and south

Texas coast, and on the Atlantic coast have suitable water clarity and substrate for the growth of submerged vegetation. In these estuaries, water

depth is of little importance in providing cover. The percentage of substrate

that supports growth of submerged vegetation (V lt ) is assumed to interact with

V3 to determine suitabi 1 ity of the food and cover component. Because open

water over nonvegetated substrate is i~portant for feeding, habitat suitability is assumed to decrease as cover of submerged vegetation exceeds 75%.

Along the Louisiana coast, estuaries have little submerged vegetation.

For estuaries with naturally unvegetated bottoms, the food and cover life

requisites for red drum are considered separately (Figure 1). Food quality is

assumed to be determined by the percentage of open water edge fri nged with

wetlands (V 3 ) alone. Substrate composition and mean depth define cover suitability. In the model, substrate (V s ) is classified as five types: mud, fine

sand, coars€ sand, rock, and shell. Over this range of substrates, mud represents the optimal and shell the least suitable habitat. ~1ean depth (Vd of

1.5-2.5 m (4.9-8.2 ft) at low tide is considered optimum.

Suitability Index (SI) Graphs for Habitat Variables

Graph i c representati ons of the rel ati on between habitat vari ab 1es and

habitat suitability are shown in the following section. All variables are

associ ated wi th es tuari ne (E) habitat. The data sources and assumpti ons

associated with documentation of suitability index graphs are shown in

Table 1.

5
Habitat variable

Vegetated Substrate

Life reguisHe

V2 Mean salinity --

V1 Mean temperature Water quality

V3

V..

Percentage of open water

fringed with perSistent> emergent vegetation

Food/Cover

Percentage of open water

supporting growth of

submerged vegetation

HSI

Figure 1. The relations of habitat variables and life requisites to the habitat suitability index for

larval and juvenile red drum in estuarine habitat with vegetated and naturally nonvegetated substrate.
Habitat Variable Sui~ability Graph

E Mean water 1.0

t enpe ra ture

during period )( 0.8 of 1arval CD

development. "

c

- 0.6

>- :=

:a 0.4 as

:t:

:J

en 0.2

0.0

10 20 30 40

E V2 Mean sal inity 1.

during period

of 1arv al )( o.

development. CD

"

c

0.6

>-

:=

:a 0.4 as

:t:

:J

en 0.2

0.0

0 10 20 30 40 50

ppt

1.0

E V3 Percentage of )( 0.8

open water CD

edge fri nged "

c

wi th pers is- - 0.6

>- tent emergent :t:

vegetation. -

n 0.4 as

.'!::

:J

en 0.2

0.0

0 20 40 60 80 100

"

7
Habitat

E

Variable Su i tabi 1i ty Graph

Percentage of 1.0

area covered

by su bmerged )( 0.8 vegetation. CD

'tJ

.5 0.6 >-

:E

=

0.4 «I

..';

en 0.2

0.0

0 20 40 60 80

%

-

I1.0

0.2

0.6

0.0

0.4

0.8

E Vs Substrate

composition.

)(

(1 ) Mud CD

(2) Fine sand

"

e

(3) Coarse >-

sand

(4) Rock =:Q

(5) Shell as

=:::s

en

1 2 3 4 5

Class

E V6 ~,1ean depth of 1.

estuarine

open water )( o.

area at low CD

tide. "

e

0.6

>-

=

:Q 0.4 as

..

-:;

en 0.2

0.0

0 1 2 3 4 5

Depth (m)

8
Table 1. Data sources and assumptions for red drum suitability indexes.

Variable and source

Vl Holt et ale 1981a

Holt et ale 1981b

Vz Ho 1t et a1• 1981a

Holt et ale 1981b

V3 Yokel 1966

Turner 1977

Bahr et ale 1982

V4 Pearson 1929

Mil es 1950

Simmons and Breuer 1952 ~Jei nstei n 1979

Hol t et al. 1983

V5 Miles 1950

Simmons and Breuer 1962

Hol t et al , 1983

V6 Bass and Avaul t 1975

Dr. William Herke,

Louisiana State Univ.

(unpu b1ish ed dat a)

Assumptions

Temperature associated wit~ highest

survival is op t inum ,

Salinity associated with highest

survival rate is optimum.

Intertidal we t l ands are rel ated to

productivity and loss of wetlands

results in a reduction in carrying

capacity.

Submerged vegetati on prov ides cover,

but some unve~etated bottom is

necessary for feeding by 1arval and

juvenile red drum.

Red drum larvae and juveniles prefer

mud substrate over sand and rock; shell

i s unsui tab1e.

Larvae and juveniles prefer water

depths of 1.5-2.5 m in naturally

unv egeta ted bottoms.

Component Index and Habitat Suitabil ity Index Equations

The following equations are suggested for combining habitat variables to

obtain component index and HSI values for larval and juvenile red drum.

Estuaries with submerged vegetation.

Component

Water Qual ity (WQ)

Food/Cover (FC)

Equation

(SI 2 x SI )1/3 Vl Vz

HSI = WQ or FC, whichever is lower

9
Estua ri es with little or no submerged vegetation.

Component Equation

2

x 51

V2 Water Qua 1i ty (WQ) (51 )1/3 h

Food (F) 51 V3

Cover (C) (51 Vs x 51 )1/2 V6

H51 = WQ, F, or C, whichever is lowest

Hypothetical data sets (Tables 2 and 3) were used to calculate component and H51 values for larval and juvenile red drum. The resulting H51 values are

believed to reflect the relative potential of these habitats to support red

drum.

Table 2. Calculations of water quality (WQ) and food and cover (FC) component

indices and the habitat suitability index (H51) for three sample data sets for

larval and juvenile red drum from an estuary with submerged vegetation.

f~odel component Data set 1 Data set 2 Data set 3

Data 51 Data 51 Data 51

V1 16 ° C 0.1 25° C 1.0 22° C 0.7

V2 26 ppt 1.0 30 ppt 1.0 35 ppt 0.75

V3 10% 0.28 90% 0.92 50% 0.6

V4 15% 0.3 50% 1.0 80% 0.8

Vs

V6

WQ 0.22 1.0 0.72

FC 0.29 0.96 0.69

H51 0.22 0.96 0.69

10
;

Table 3. Calculations of water quality (WQ), food (F), and cover (C) component indices and the habitat suitability index (H5I) for three sample data

sets for 1arva 1 and juvenil e red drum from an estuary with 1ittl e or no submerged vegetation. Numbers in parentheses indicate substrate composition

cl ass.

Model component Data set 1 Data set 2 Data set 3

Data 51 Data 51 Data 51

Vl 16° C 0.1 25° C 1.0 22° C 0.7

Vz 26 ppt 1.0 30 ppt 1.0 35 ppt 0.75

V3 10% 0.28 90% 0.92 50% 0.6

V4

Vs (4 ) 0.2 (1) 1.0 (3 ) 0.5

V6 0.3 m 0.2 1.5 m 1.0 2.5 m 1.0

WQ 0.22 1.0 0.72

F 0.28 0.92 0.6

C 0.2 1.0 0.71

H5I 0.2 0.92 0.6

Field Use of Models

Information required for use of this model may be available from published reports. Table 4 lists techniques suggested for obtaining information

necessary to use suitability graphs.

It may be prudent to alter the H5I model structure for some field applications. As noted previously, the water quality component is assumed to

affect the larval life stage alone. Because red drum can disperse to new

habitat after metamorphosis to the juvenile stage, water quality should not

influence habitat suitability in areas believed to be used by post-larval

stages only. In such areas, the water quality component is dropped from the

H5I equations presented above.

11
Table 4. Suggested methods for field measurement of variables in the red drum

HS I model.

Variable

V1 Mean temperature

V2 Mean sal inity

V3 Percentage of open water

fringed with persistent

emergent veqeta t i on

V4 Percentage of subnerq ed

vegeta t ion

Vs Dominant substrate

V6 Depth

Method

Existing data or field sampl ing

with a the rmometer.

Existing data or field sampling

with a refractometer or salinity

meter.

Calculate by using aerial photographs, existing maps, or LANDSAT

imagery (Short 1982).

Calculate by using same methods

sugges ted fo r V3.

A core sampler or several types of

dredges can be used (Edmondson and

Win berg 1971).

Charts, depth finder, or sounding.

Interpreting Model Outputs

The red drum HSI represents the potential of a habitat to support fish of

this species. Because actual abundance may be determined by many nonhabitat

factors excl uded from thi s model, there may be no correl ati on between model

output and red dr-un population numbers. The sound use of the HSI consists of

comparison of habitat potential of a single area at different points in time

or of different areas at a single point in time.

12
REFER ENC ES

Ba hr , [·1.L., J .W. Day, and J.H. Stone. 1982. Energy cost-accounting of Louisiana fishery production. Estuaries 5(3):209-215.

Bass, R•.J., and J.l~. Avault. 1975. Food habits, length-weight relationship,

condition factor, and growth of juvenile red drum, Sciaenops ocellata, in

Louisiana. Trans. Am. Fish. Soc. 104(1):35-45.

Benson, N.G., ed• 1982. Li fe history requirements of sel ected finfish and

shellfish in Mississippi Sound and adjacent waters. U.S. Fish Wildl.

Servo Biol. Servo Proqr am. FHS/OBS-31/51. 97 PD.

Boothby, R.N., and J.vJ. Avault. 1971. Food habits, length-weight relationship, and condition factor of the red drum (Sciaeno s ocellata) in southeastern Louisiana. Trans. Am. Fish. Soc. 100 2 :290-295.

Cowa rd in , L.M., V. Carter, F.C. Golet, and E.1. LaRoe. 1979. Classification

wetlands and deepwater habitats of the United States. U.S. Fish Wildl.

Servo 8iol. Servo Program. 8"'S/OBS-79/31. 103 pp ,

Edmondson, W.T., and G.G. W-inberg, eds. 1971. Secondary productivity in

fresh waters. Blackwell Scientific Publications, Oxford. 358 pp ,

Gunter, G. 1941. Death of fishes to cold on the Texas coast, January, 1940.

Ecology 22(2): 203-208.

Gunter, G., and J.H. Hildebrand. 1951. Destruction of fishes and other organi sms on the south Texas coast by the col d wave of January 28- February

3~ 1951. Ecology 32: 731-736.

Hi l debrand , S.F., and W.C. Schroeder. 1928. The fishes of Chesapeake Bay.

U.S. Bur. Fish. Bull. 43, Part 1:1-366.

Holt, J.~ R. Godbou t , and C.R. Arnold. 1981a. Effects of temperature and

salinity on egg hatching and larval survival of red drum, Sciaenops

ocellata. U.S. Natl. Mar. Fish. Servo Fish. Bull. 79(3):569-573.

Hol t , J., A.G. Johnson, C.R. Arnold, W.A. Fable, and 1.0. Williams. 1981b.

Description of eggs and 1arvae of 1aboratory reared red drum, Sciaenops

ocellata. Copeia 1981:751-756.

Holt~ S.A., C.L. K'i t t inq , and C.R. Arnold. 1983. Distribution of young red

drum among different sea-grass meadows. Trans. Am. Fish. Soc. 112:

267-271.

13
Las swel l , J.L es G. Garza s and W.H. Bailey.

introductions into fresh waters of Texas.

Assoc. Fi sh Wildl. Agenci es 31 :399-403.

1977. Status of mari ne fi sh

Proc. Annu. Conf , Southeast.

Mansueti s R.J. 1960. Restriction of very young red drums Sciaenops ocelleta s

to shallow estuarine waters of Chesapeake Bay during late autumn. Chesapeake Sci. 1:207-210.

~1atlocks G.C. 1980. History and management of the red drum fishery. Pages

37-54 in Proceedings of the colloquium on the biology and management of

red drum and seatrout. Gulf States Marine Fisheries Commissions Ocean

Springss Miss.

Mays R.C. 1974. Larval mortal ity in marine fishes and the critical period

concept. Pages 3-19 in J.H.S. Bl ax ter, ed. The early 1ife history of

fi she Springer-Verl ag~New York.

Miles s D.W. 1950. The life histories of the spotted seatrout , Cynoscion

nebul os a , and the r-edf tsh, Sciaeno s ocellatus. Tex. Game Fish Oyster

Comm. Mar. Lab. Annu. Rep. {1949-195 :66-103.

Nelsons W.R.s M.C. Inghams and W.E. Schaaf. 1977. Larval transport and yearclass strength of Atlantic menhaden, Brevoortia tyrannus. U.S. Natl.

Ma r • Fish. Ser v• Fish. Bull. 75(1 ) : 23-4 2•

Overstr-ee t , R.f4.s and R.W. Heard. 1978. Food of the red drums Sciaenops

ocelleta s from Mississippi Sound. Gulf Res. Rep. 6(2):131-139.

Overstreet , R.M. 1983. Aspects of the biology of the red drums Sciaenops

ocel l a tus, in Mississippi. Gulf Res. Rep. Supple 1 June 1983:45-68.

Pear-son, J.C. 1929. Natural history and conservation of the redfish and

other commercial sciaenids on the Texas coast. Bur. Fish. Bull. 64:

178-194.

Pe rre t , W,S' s J.E. Weavers R.O. Will"iams s P.L. Johansen, 1.D. McIlwain s R.C.

Raulerson s and W.M. Tatum. 1980. Fishery profiles of red drum and spotted seatrout. Gulf States Mar. Fish. Comm. No.6. 66 pp.

Shenker, J.M. s and J.M. Dean. 1979. The utilization of an intertidal salt

marsh creek by larval and juvenile fishes: abundances diversity and temporal variation. Estuaries 2(2):154-163.

Shorts N.M. 1982. The LANDSAT tutorial workbook: basics of satellite remote

sensing. National Aeronautics and Space Administration. NASA Ref. Publ.

1078.

S'imrncns , E.G. s and J.P. Breuer. 1962. A study of red t tsh, Sciaenops ocelleta

(Linnaeus ) , and black drums Pegonias cromis (Linnaeus). Publ. Ins t , Mar.

Sci. Univ. Tex. 8:184-211.

14
Theil ing, D.L., and H.A. Loyacano. 1976. Age and growth of red drum from a

salt water marsh impoundment in South Carolina. Trans. Am. Fish. Soc.

105(1) :41-44.

Turner, R.E. 1977. Intertidal vegetation and commercial yields of penaeid

shrimp. Trans. Am. Fish. Soc. 106:411-416.

U.S. Department of Commerce. 1981. Fishery statistics of the United States

1980. Current Fisheries Statistics NOAA No. 8100. 132 pp ,

U.S. Fish and Wildlife Service. 1980. Habitat evaluation procedures (HEP).

ESM 102. U.S. Fish Wildl. Servo Washington, D.C. n.p.

Vladimirov, V.1. 1974. Critical periods in the development of fishes. J.

Ichthyol. (6):851-868.

Welsh, W.W., and C.M. Breder. 1924. Contribution to the life history of the

Sciaenidae of the Eastern United States. Bull. U.S. Bur. Fish. 39:

141-201.

Weinstein, M.P. 1979. Shallow marsh habitats as primary nurseries for fishes

and shellfish, Cape Fear River, North Carolina. U.S. Natl. Mar. Fish.

Servo Fish. Bull. 77(2):339-357.

Yokel, B.J. 1966. A contribution to the biology and distribution of the red

drum, Sciaenops ocellata. M.S. Thesis. University of Miami, Coral

Gables, Fla. 160 pp,

15
50272 -101 I 3. Recipient's Accession No_

I

Habitat Suitability Index Models: Larval and Juvenile Red Drum

~--------------- ------- ~~~- ----------~-~-----

7. Author(s)

J. Buckl ey

9. Performing Organization Name and Address

U.s. Fish and Wildlife Service

l'1assachusetts Cooperative Fishery Researc'rt Unit

Uni vel's ity of f1assachusetts ~nherst. MA 01003

14.

f------------------------~----~-------- --~-~ ~--____r~-~- ~~----~~ --- ~-----~~

12. Sponsoring Organization Name and Address : 13. Type of Report & Pertod COvereo

U.S. Fish and Wildlife Service

Jivision of Biological Services

National Coastal Ecosystems Team

1010 Gause Boulevard. Slidell. LA 70458 15. Supplementary Notes

H•. Abstract (limit: 200 words)

A r ev iew and synthesis of existing information were used to develop a habitat model

for l arval and juvenile r ed drum. The model is scaled to produce an index of habitat

sut tabt l t ty between 0 (unsuitable habitat) and 1 (optimally suitable habitat) for estuarine areas along the Gulf of Mexico and Atlantic coasts. Habitat suitabil ity indices

are designed for use with 'iab i te t evaluation procedures developed by the U.S. Fish and

\~ildlife Service. Guidelines for model application and techniques for est imat inq model

variables dre provided.

+.~----:-:-:-::----=:----------------------------

--~---------~------~--------~------------------~------------~~-------------1

17. Document Analysis a. Descriptors

Mathematical models

Fishes

Estuaries

b. Identifiers/Open-Ended Terms

Habitat Suitability Index

Red drum

Sciaenops ocellatus

Unl imited

c. COSA TI Field/Group

--------------------- -------------c----~-~-----.----,____--------l

18. Availability Statement 19. Security Class (ThIS Report) i 21. No. of F-z.ges

__ U.n cJ~~S sifi ~d __v~-.:+:_12__ 20. Security Class (ThiS Page) i ZZ. Price

Unclassified ' (See ANSI-Z39,IS) OPTIONAL FO::!'" 272 ~-77)

(Formerly NT 5-35)

Department of Cornme-c e
els. 19512

SKlil .U54 roo 8

IIII ~~~~I i~11

Habitat suitability index

Buckley, Jack.

" --

'. ..... HawaUan IlIIands

-t:r HeadQua'lefs DIVISion a t BIological

Services . Wasrung fon DC

)( Eastern Energy and Land Use Team

Lee lO'lm WV

* National Coas tal Ecosy stems Team

Slidell LA

• Wes tern Energy ana land Use Team

Fl COllins CO

• t.oc anons of RegIonal Ottice s

I

J- - - - ---6 1

r-- -~.

-- J.-, • 1 ---

I

,--,

I L

1 2

REGION 1

Regional Director

U.S. Fish and Wildlife Service

Lloyd Five Hundred Building, Suite 1692

500 N.E. Multnomah Stree '

Portland, Oregon 97232

REGION 2

Regional Director

U.S. Fish and Wildlife Service

P.O. Box 1306

Albuquerque, New Mexico 87103

REGION 3

Regional Director

U.S. Fish and Wildlife Service

Federal Building, Fort Snelling

Twin Cities, Minnesota 55111

REGION 4

Regional Director

U.S. Fish and Wildlife Service

Richard B. Russell Building

7S Spring Street, S.W.

Atlanta, Georgia 30303

REGION 5

Regional Director

U.S. Fish and Wildlife Service

One Gateway Center

Newton Corner, Massachuset ts 02158

REGION 6

Regional Director

U.S. Fish and Wildlife Service

P.O. Box 25486

Denver Federal Center

Denver, Colorado 80225

REGION 7

Regional Director

U.S. Fish and Wildlife Service

1011 E. Tudor Road

Anchorage, Alaska 99503
DEPARTMENT OF THE INTERIOR

u.s. FISH AND WILDLIFE SERVICE

l ...... •·l b H A WILULI.": ~t.:HVK·t.:

'. ,.. ' ''''-,\, ...

As the Nation's principal conservation agency, the Department of the Interior has responsibility for most of our .nationally owned public lands and natural resources. This includes

fostering the wisest use of our land and water resources, protecting our fish and wildlife,

preserving th&environmental and cultural values of our national parks and historical places,

and providing for the enjoyment of life through outdoor recreation. The Department assesses our energy and mineral resources and works to assure that their development is in

the best interests of all our people. The Department also has a major responsibility for

American Indian reservation communities and for people who live in island territories under

U.S. administration.