U.S. Department of the Interior

Bureau of Land Management

BLM Alaska Open File Report 126

BLM/AK/ST-14/004+6710+F0210

February 2014

Limestone Gulch, White Mountains 

National Recreation Area: Natural, 

Cultural, and Biological Karst 

Reconnaissance, 2002-2005

Robin O. Mills, Robert Sattler, and Nancy H. Bigelow

BLM

Alaska
Mission Statement

The Bureau of Land Management (BLM) sustains the health, diversity and productivity of the public lands 

for the use and enjoyment of present and future generations.

Authors

Robin O. Mills is an Archaeologist with the Eastern Interior Field Office, Fairbanks, Alaska.

Cover

Robert Sattler resting amongst upland alpine vegetation in the vicinity of limestone outcrops; Limestone 

Gulch region, White Mountains Recreation Area, Alaska. 

Open File Reports

Open file reports present the results of inventories or other investigations published outside the formal 

BLM-Alaska technical publication series. These reports can include preliminary or incomplete data and 

are not published and distributed in quantity. 

Reports are available while supplies last from BLM Public Information Center, 222 West 7th Avenue, 

#13, Anchorage, Alaska 99513 (907) 271-5960. Copies are also available for inspection at the Alaska 

Resource Library and Information Service (Anchorage), the United States Department of the Interior 

Resources Library in Washington D.C., various libraries of the University of Alaska, the BLM National 

Business Center Library (Denver), and other selected locations. 

A complete bibliography of all BLM-Alaska scientific reports can be found on the Internet at:

http://www.blm.gov/ak/st/en/info/gen_pubs/ofr.html.
Limestone Gulch, White Mountains 

National Recreation Area: Natural, 

Cultural, and Biological Karst 

Reconnaissance, 2002-2005

By

Robin O. Mills, Bureau of Land Management

with contributions by

Robert Sattler, Tanana Chiefs Conference and Nancy H. Bigelow, Alaska Quaternary Center

BLM Open File Report 126

February 2014

U.S. Department of the Interior

Bureau of Land Management

Eastern Interior Field Office

1150 University Ave.

Fairbanks, AK 99709

Table of Contents

Introduction: The Project Background 7

Results 9

Basic Cave Data 11

Speleothems 28

Hydrology 29

Biology – birds 29

Biology – mammals 31

Archaeology 32

Paleontology 32

Karst Feature #3 33

Karst Feature #34 33

Karst Feature #37 33

Karst Feature #46 34

Karst Feature #96 57

Karst Feature #102 60

Summary of the White Mountains Karst Surveys 61

References Cited 63

Appendix 1. Cave/Rock Shelter Inventory Form 65

Appendix 2. Samples collected and accessioned to the University of Alaska Museum of the North,

Earth Sciences Department (UAMES2009.013ESCI) 69

Appendix 3. Karst Data 2002-2005 Database 71

Appendix 4. Karst Feature #46, Limestone Gulch Region, WMNRA. Loss-On-Ignition data

from 2005 column excavation 73

Appendix 5. Karst Feature #46, Limestone Gulch Region, WMNRA. Raw pollen data

from 2005 column excavation 74

Acknowledgments inside back cover

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Introduction: The Project Background

This report outlines the findings of a natural, biological and cultural survey of karstic features in the Limestone 

Gulch area of the White Mountains National Recreation Area (WMNRA), managed by the Bureau of Land 

Management – Fairbanks District Office (BLM). The WMNRA is a nearly 1 million acre contiguous land unit 

located in central-eastern interior Alaska, northeast of the city of Fairbanks (Figure 1). The survey occurred 

during the summer months of 2002 through 2005, and was prompted by an impromptu discovery of a bison 

bone inside of a small cave in the Limestone Gulch area of the WMNRA in the spring of 2001 (Figure 

2). Radiocarbon analysis on the bone returned an assay around 13,000 before present, dating to the late 

Pleistocene epoch. 

The potential of locating late Pleistocene paleontological and possibly even archaeological materials prompted 

me to develop a survey plan for this area, which was initiated the following summer. In this regard, a series 

of mostly volunteer surveyors from various outdoor backgrounds and specialties (i.e., spelunkers; plant and 

bird specialists; archaeologists; a quaternary paleoecologist; recreation specialists) were recruited to survey 

and record karst features in the area (see Acknowledgements). Three to five people participated in each survey 

for three to five days at a time. Other resource personnel in the BLM were contacted, and asked to contribute 

to the development of a “caving form” to be filled out by the surveyors (Appendix 1). The form prompted 

the surveyors to record basic information about various types of data: (1) location, (2) the nature of the 

Figure 1. Location of the White Mountains National Recreation Area in Alaska.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005 8

Figure 2. Location of the karst survey area in the White Mountains National Recreation Area.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

9

karst feature, in terms of the presence of various caving features, as well as quantifiable measurements, (3) 

cultural/archaeological, (4) paleontological, (5) mammalian biological, including bats, (6) avian biological, 

(7) geological, (8) hydrological, and (9) vegetation. In addition, a standard suite of photos of each karst feature 

was recorded, and simple top or plan view maps were recorded for each rock shelter or cave feature. Where 

feasible, a standard test pit (circa 35 cm diameter) was also excavated inside each cave or rock shelter to 

assess its buried archaeological and paleontological potential, and the basic stratigraphy of each test pit was 

recorded.

The primary goal of the survey was to gather basic information in order to highlight the nature of the resources 

available in this largely under-surveyed area. Experts in specific fields (e.g., paleontologists; large mammal 

biologists; recreationists) can now use the data provided here to better plan their own field studies.

As can be expected, the quality of the data that was recorded varied widely from karst feature to feature, 

depending largely upon individual knowledge and the date of each survey. Simply put, the data recorded 

during later surveys are an improvement over those gathered during earlier surveys; as critical comments on 

earlier caving forms were given back to the surveyors from one trip to the next, the nature of the data gathered 

and its standardization improved. 

Besides proactively gathering natural historical data in this area, another factor that prompted this project is 

the possibility of a hiking trail being constructed up Fossil Creek, from the Beaver Creek National Wild & 

Scenic River corridor, next to the Limestone Gulch area. The Record of Decision, Resource Management 

Plan for the WMNRA (1986) outlines the possibility of just such a trail being constructed. Although a fuller 

Environmental Assessment would likely be involved by the BLM’s Eastern Interior Field Office (EIFO) if the 

decision to build this trail is ever made, this preliminary study should provide baseline data useful to some 

of the various programs that would be involved at that time (i.e., recreation, archaeology, wildlife biology). 

An assortment of samples were collected during the course of the surveys, including owl pellets, soils samples, 

and faunal samples which include large mammal bones, microtine bones, bird bones, mollusk shell fragments, 

feathers, and fish bones. Appendix 2 lists all of the samples collected during these surveys. All samples have 

been accessioned to, and reside at the University of Alaska Museum of the North’s Earth Sciences Department 

(accession UAMES2009.013.ESCI).

Results

Eight surveys took place, one in 2002, four in 2003, one in 2004, and two in 2005 (Figure 3). Most surveys 

lasted for three days. Unfortunately for the project, the 2004 and 2005 field seasons were two of the worst 

seasons for wildland fire in Alaska since records began to be kept in the 1950s, in terms of total acreage 

burned. Since our project relied upon BLM-Alaska Fire Service (AFS) contracted helicopters to transport 

our survey crews into and out of the Limestone Gulch region, only a limited number of surveys could be 

conducted during those two years. In short, the helicopters were needed elsewhere for fire-related activities, 

and not available for extra resource-related projects like the karst project.

Nonetheless, approximately 3,350 acres were 100% ground covered by pedestrian survey during this project, 

and 102 karstic features were located and recorded (Figures 4-12). Of these, 12 are natural stone arches, with 

the remainder being caves and rock shelters. As I could not locate a standardized definition differentiating 

what a “cave” is from what a “rock shelter” is, all further references to this type of feature (i.e., an indentation 

into but not through a rock wall) will hereafter be referred to as a “cave” in this report. The basic data 

from all forms for all karst features are presented in Appendix 3. Figures 13-21 provide illustrative examples 

of the Limestone Gulch topography in which the surveys occurred, as well as the types of vegetation and 

groundcover found in the area today.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 3. Boundary extents of the eight surveys in the White Mountains National Recreation Area, plus all 

karst feature localtions. (1) 5/23/03 – 5/25/03; (2) 6/06/03 – 6/09-03; (3) 7/03/03 – 7/04/03; (4) 8/02/03 – 8/04/03; (5) 

6/05/04 – 6/07/04; (6) 7/16/05 – 7/18/05; (7) 8/27/05 – 8/29/05; (8) 7/22/02 – 7/23/02.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Basic Cave Data

In sum, most of the caves located during the surveys are relatively small. Figure 22 presents the greatest length 

of 76 caves whose lengths were recorded; almost two-thirds (63%; n=57) have a greatest length of 5 meters 

or less, while only four (5%) have lengths greater than 15 meters. Figure 23 presents the greatest width versus 

height for each cave mouth or entrance (n=89; one cave was not reachable). Here, 89% (n=79) of the caves 

had entrances smaller than 4 x 6 meters (width v. height), and 60% had entrances smaller than 2.5 x 4 meters. 
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 4. Map showing locations of close-up data maps, Figures 5-12.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 5. Close-up map showing karst feature locations, northern portion of Limestone Gulch. 

Refer to Figure 4 for general map locale.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 6. Close-up map showing karst feature locations, northeastern portion of Limestone Gulch. 

Refer to Figure 4 for general map locale.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 7. Close-up map showing karst feature locations, north-central portion of Limestone Gulch. 

Refer to Figure 4 for general map locale.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 8. Close-up map showing karst feature locations, central portion of Limestone Gulch. 

Refer to Figure 4 for general map locale.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 9. Close-up map showing karst feature locations, western portion of Limestone Gulch. 

Refer to Figure 4 for general map locale.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 10. Close-up map showing karst feature locations, southeastern portion of Limestone Gulch. 

Refer to Figure 4 for general map locale.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 11. Close-up map showing karst feature locations, south-central portion of Limestone Gulch. 

Refer to Figure 4 for general map locale.
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Figure 12. Close-up map showing karst feature locations, southern portion of Limestone Gulch. 

Refer to Figure 4 for general map locale.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 13. Steve Springer and Andrea Hunter relax on a grassy hillside; Limestone Gulch region, 

WMNRA. Note the open rocky talus slopes in the background, and spruce trees on the lower slopes and 

creeping up the drainages.

Figure 14. Andrea Hunter on an exposed grassy hillside; Limestone Gulch region, WMNRA. Note the 

mixed grassy-talus slopes in the background, and spruce trees on the lower slopes and creeping up 

the drainages.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 15. Carrie Barta and Andrea Hunter on a grassy slope in front of a limestone outcrop with a cave 

set in it; Limestone Gulch region, WMNRA. Note the pockets of spruce on this otherwise open slope. 

Figure 16. Carrie Barta on a high outcrop overlooking a limestone ridge; Limestone Gulch region, 

WMNRA. Note the highly variable vegetation pattern, a wide spruce area next to a talus slope area with 

upland alpine vegetation.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 17. A steep-sided limestone ridge, with spruce and thick sphagnum moss 

on the slopes below; Limestone Gulch region, WMNRA. Note the tiny person near 

center for scale.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Figure 18. A surveyor assists in recording a cave in the sheer limestone slope 

behind the spruce tree, center of photo; Limestone Gulch region, WMNRA. 
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25

Figure 19. Limestone ridge system overlooking the Beaver Creek drainage in the vicinity of Karst 

Feature #46; Limestone Gulch region, WMNRA. Note the upland alpine vegetation on the slopes.

Figure 20. Robert Sattler resting amongst upland alpine vegetation in the 

vicinity of limestone outcrops; Limestone Gulch region, WMNRA.
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Figure 21. A cave set into a limestone outcrop, with thick upland alpine vegetation in the foreground; Limestone 

Gulch region, WMNRA. Note the backpacks in front of the cave for scale.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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0

10

20

30

40

50

60

1-5 6-10 11-15 16-20 21-25 26-30 31-35 36-40

Length (meters)

Count

all caves bear dens

Figure 22. Greatest length of all caves (n=76 caves measured), and those with bear dens (n=9).

0

2

4

6

8

10

12

14

16

0 2 4 6 8 10 12

Width (meters)

Height (meters)

Figure 23. Cave / Rock shelter greatest width vs. height of mouth or entrance (n=89).

Likewise, most of the caves’ layouts or plan views are relatively straightforward. Figure 24 presents the 

number of chambers present off of a cave’s main entrance chamber, for all 90 caves in the study. The vast 

majority (82%; n=74) possess only the main entrance chamber that you initially enter when passing through 

the cave mouth. Of those 16 caves that have an additional chamber, only four have more than one. 
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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74

12

3 1

0

20

40

60

80

None One Two Three

Number of Side Chambers off the Main Chamber

Number of Caves / Rock Shelters

Figure 24. Number of chambers present off of the main entrance chamber (n=90).

Speleothems

An attempt was made to determine which types of speleothems, if any, are present in the caves in the survey 

area. Collectively, speleothems are calcium carbonate or calcium sulfate formations that form or are deposited 

in caves by the precipitation of solutes from seeping groundwater. Large, spectacular speleothems are an 

attraction to recreational and professional cavers, or spelunkers, and thus an attempt was made to note their 

presence in the White Mountains caves. Visually, the nature of the speleothem formations in the Limestone 

Gulch caves is less than fantastic; no caverns filled with large stalactites, columns, or large masses of flowstone 

were found. Succinctly, most of the caves in this area appear to be too active -in terms of active spalling 

of chunks of limestone from their walls and ceilings- for the creation of large, “impressive” speleothem 

formations, which can take millennia to form in relatively stable conditions. 

Nonetheless, various forms of speleothems were noted in 45% (n=41) of the 90 caves examined (Figure 25). 

The most frequent of these were popcorn formations noted in 24 of the caves. Popcorn is small “knobbly” 

calcite formations on walls or ceilings. Small areas of flowstone were also noted in seven caves. Flowstone is 

probably the most common speleothem type, composed mostly of calcite or carbonate, and forms in growing, 

accumulating overlapping layers on a surface from the precipitation of actively flowing water. Five caves 

were noted as having moon milk deposits, which are smooth, milky white, often “bubbly” deposits that form 

mostly on cave walls. Boxwork, seen in three of the caves, are made from thin plates of calcite that develop 

out of cave walls and ceilings, forming a “honeycomb” or “box” pattern as the plates interconnect. A single 

instance of a two–inch long stalactite was noted in one cave; stalactites hang down from the ceilings of caves, 

and form when calcium carbonate and other minerals precipitate from dripping water. And lastly, one case 

of helictite formation was noted. This precipitate is formed when water is squeezed out of cracks in the rock, 

forming “bush-like” deposits projecting out of walls and ceilings.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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0

5

10

15

20

25

30

popcorn flowstone moon milk boxwork stalactite helictite

Count

Figure 25. Numbers of caves with different types of speleothems.

Hydrology

Very little in the way of hydrological features were noted during the survey. Again, cave systems potentially 

attractive to spelunkers often have large, elaborate hydrological systems (e.g., underground streams/rivers, 

falls, etc.). However, only standing pools of water were noted in some of the caves in the White Mountains, 

and these were not fed by subterranean sources, but supplied instead from melted snow which accumulated 

during the winter months. None of these were very deep, measuring only in inches.

Biology – birds

The project was lucky to have personnel able to identify various live birds by sight and sound during many of 

the trips. Table 1 provides a listing of the birds that were positively identified during the surveys. In addition, 

10 caves had one or more instances of direct evidence of live birds inside them or at their entrances. A number 

of nests were noted inside caves or directly at their entrances, including one Peregrine falcon’s nest, one 

Townsend’s Solitaire nest (with rotten eggs), two Say’s Phoebe nests (one of which had two chicks and an 

unhatched egg), and two other unidentified species nests. 
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

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Table 1. Names of live birds noted during the survey.

COMMON NAME LATIN NAME

American Robin Turdus migratorius

Hermit Thrush Catharus guttatus

Swainson’s Thrush Catharus ustulatus

Common Raven Corvus corax

White Crowned Sparrow Zonotrichia cophrys

Red-Tailed Hawk Buteo jamaicensis

Tree Sparrow Spizella arborea

Alder Flycatcher Empidonax alnorum

Northern or Red-Shafted (common) Flicker Colaptes auratus cafer

Peregrine Falcon Falco peregrinus

Townsend’s Solitaire Myadestes townsendi

Say’s Phoebe Sayornis saya

Ruby-Crowned Kinglet Regulus calendula

Bohemian Waxwing Bombycilla garrulus

Violet-Green Swallow Tachycineta thalassina

Gyrfalcon Falco rusticolus

Varied Thrush Ixoreus naevius

Gray Crowned Rosey Finch Leucosticte tephrocotis

American Pipet Anthus spinoletta

In addition, evidence of birds having been recently eaten or regurgitated were found on the surface or floor in 

five of the caves (Karst Features #33, 35, 37, 46, 65 and 81), including pellets and scat with bones and feathers. 

The following bird remains were identified by Kevin Winker, Curator of Ornithology at the University of 

Alaska Museum of the North. Among the remains on the floor of Karst Feature #33 was a partial avian 

humerus similar to a medium-sized duck (Anseriformes?) and a single rectrix or tail feather of a Lesser 

Yellowlegs (Tringa flavipes). The one bone found on the floor of Karst Feature #35 is a wing bone of a duck, 

most likely a smallish puddle duck (Anatidae). Those from the floor of Karst Feature #37 include 10 leg and 

wing bones of ptarmigans (Lagopus muta, Lagopus lagopus) and grouse (Falcipennis canadensis, Bonasa 

umbellus). None of the surface birds bones found in Karst Feature 46 were identified, and the owl pellet from 

the floor of this feature was not broken apart to determine its specific contents. An owl pellet with plastic and 

paper in it from the floor of Karst Feature #65 was noted in the field, but not collected. Last, a near-complete 

ptarmigan (Lagopus sp.) skeleton was collected from a small upper chamber of Karst Feature #81, on a small 

ledge about 3 m above the regular cave floor. Whether the animal flew in and died of its own accord, or else 

was a cached kill of a predator that never returned to its meal, is unknown.

Incidentally, two of the karst features had plastic and paper pieces associated with the surface remains, 

reflecting the inclusion of modern trash into this largely inaccessible ecosystem: the owl pellet from Karst 

Feature 65 has both plastic and paper embedded within it, and some small fragments of plastic were found on 

the floor of Karst Feature 46.

It should be mentioned that a host of bird bones were also recovered from within the tests pits dug inside of 

several of the caves; these remains are discussed separately under Paleontology, below.
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Biology – mammals

There was no indication of bats (e.g., sightings, guano, bones, cave wall polishing) in any of the karstic 

features examined during this study. However, there was abundant evidence that other mammals are presently 

using the karst features in the Limestone Gulch vicinity. Of the 102 karst features located and recorded during 

the survey, 65% (n=66) had some evidence of present-day use by mammals; this total includes three of the 12 

natural stone arches. As with the bird identification, discussed above, we were lucky to have survey personnel 

who could accurately identify various animal sign. Figure 26 presents the number of instances of different 

sign (i.e., mostly scat, but also including animal beds, fur, wall rubbings, and distinctive gnaw marks) of 

animals encountered in the karst features. In total, 120 different animal sign was noted; more than one animal 

sign was found in many of the features.

Not surprisingly, owing to the resident Dall’s sheep (Ovis dalli dalli) population on the slopes of the White 

Mountains, sheep sign was the most prevalent animal sign noted, including 39 features where sheep scat was 

found. Nine of these also had sheep beds. A sheep metacarpal was also noted in one cave, apparently having 

been dug up by recent porcupine activity (see Paleontology, below). The bone was collected, but has not 

been radiocarbon dated. Scat from porcupines (along with recognizable porcupine gnawing and digging), 

marmots, bears, and wolverines was also found in the caves. Interestingly, nine of the caves also had current 

and relatively recent signs of bear dens in them, an item of potential interest to large-animal biologists.

In sum, the bear den caves are relatively small rooms with small entrances. Figure 22, above, includes the 

lengths of those caves where bear dens were located; eight of the nine bear den caves had greatest lengths 

of six meters or less. Likewise, Figure 27 presents the greatest width versus height for each bear den cave 

entrance. Contrasting this with Figure 23 (i.e., greatest width versus height for most caves in the study, n=89), 

above, we see that bear dens clearly fall within the small range of caves in the study area, with most of the 

entrances measuring smaller than 2.0 meters wide by 1.5 meters in height. 

36

5 6

10

15

27

39

9 9

0

5

10

15

20

25

30

35

40

45

No Sign

Wolverine

Unid. Scat

Bear

Marmot

Porcupine

Sheep

Bear Dens

Sheep Beds

# karst features

Figure 26. Numbers of instances of different types of animal sign. Sign was found in 66 karst features, 

totaling 120 instances of different animal sign recorded.
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0

2

4

6

8

10

12

14

16

0 2 4 6 8 10 12

Width (meters)

Height (meters)

Figure 27. Cave / Rock shelter greatest width vs. height of mouths or entrances for those caves exhibiting bear 

dens (n=9).

In addition to the scat already referred to above, evidence of mammals having been recently eaten were found 

on the surface or floor in four of the caves (Karst Features #37, 46, 87, 92). Karst Feature #37 had the distal 

femur of a snowshoe hare (Lepus americanus), an unidentified microtine mandible, and about five small bone 

chunks of medium-large-sized mammals (e.g., sheep, caribou), including a rib fragment that has clearly been 

sawn through with a metal saw, this latter likely scavenged from a recent hunter’s camp. Karst Feature #46, of 

which much more is written under Paleontology, below, had a few bones on the surface, including microtine 

mammal remains and a couple of metal-sawn medium-large mammal (e.g., sheep, caribou) bone fragments. 

Last, a medium-large mammal bone splinter was found on the surface of Karst Feature #87, and two on the 

surface of Karst Feature #92. 

Archaeology

No prehistoric cultural artifacts were noted during the survey project, neither during the general reconnaissance 

for karst features, nor within and around the features themselves. Standard test pits (circa 35-40 cm diameter) 

were systematically dug inside the drip line of most caves encountered, specifically looking for buried cultural 

and paleontological materials. No cultural materials were located within any test pit. A few modern-day historic 

surface sites were noted during the survey, none of them historic in age (i.e., >50 years). These included a 

contemporary fire ring with some modern trash; likely a recent sheep hunter’s camp.

Paleontology

As above, surveyors systematically attempted to dig one standard test pit (circa 35-40 cm diameter) just inside 

the drip line of all caves recorded. However, this could only be accomplished in 42 of the 90 caves encountered. 

Two main factors prevented test pits from being excavated in more than half of the caves encountered: (1) 

surveys carried out in May and early June (or later, in specific topographic settings) encountered frozen 

ground that was too frozen to be dug with hand tools, and (2) the active nature of spalling of limestone blocks 

from the walls and ceiling covered the present-day floor of many of the caves with thick layers of “roof fall”. 

Regardless, of the 42 caves where test pits were excavated, four encountered buried faunal material: Karst 

Features #3, #34, #37, and #46.
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In addition, paleontological, or potentially paleontological faunal materials were found on the floor or surface 

of two more of the caves examined, Karst Features #96 and #102. As explained below, these were likely 

originally buried materials that have been brought to the surface through natural taphonomic processes of 

contemporary animal digging. These six caves will each be discussed, next.

Karst Feature #3

This small cave measured 4 m maximum width by 8.5 m in maximum depth or length. The test pit in this 

feature reached a depth of only 30 cm and yielded a small collection of avian faunal remains. Dr. Kevin 

Winker, Curator of Ornithology at University of Alaska Museum of the North, examined the bird remains 

from this and all of the karst features in the survey, comparing them to UAM’s bird faunal collections. Three 

of the elements were identified to genus or species. The first is a partial wing bone of a Spruce Grouse, Willow 

Ptarmigan, or Ruffed Grouse (Falcipennis canadensis, Lagopus lagopus, or Bonasa umbellus), the second is a 

lower leg bone of a Willow Ptarmigan, and the last is a wing bone of a duck, probably a mid-sized a dabbling 

duck (Anas sp.), which is a group of ducks that includes mallards, wigeons, teals, pintails and shovelers. No 

stratigraphic information was recorded by the surveyors; no identifiable microtine bones were excavated from 

the test pit; no radiocarbon dates have been run. 

Karst Feature #34

This small cave measured only 1.5 m maximum width by 3.0 m in maximum depth. The test pit here measured 

45 cm in depth. Numerous bird and small mammal bones, and about 10-20 small fragments of mammal bones 

from medium-large sized mammals (e.g., coyote, wolf, sheep, caribou) were found in the lower-most 30 cm of 

the test pit. The excavators described the stratigraphy as comprising dark brown “clay” (likely a silt or clayey 

silt) from top to bottom of the profile. The avian bones in the collection were examined by Dr. Kevin Winker, 

Curator of Ornithology at University of Alaska Museum of the North, who identified 12 of them to genus or 

species level, including three “legs” bones of a Rock Ptarmigan (Lagopus muta), three “hand” bone s of a 

ptarmigan (Lagopus sp.) or grouse (Falcipennis canadensis or Bonasa umbellus), a partial leg bone of a small 

duck (likely Anas sp.), a wing bone of a ptarmigan or grouse, a portion of a lower mandible of a ptarmigan 

or grouse, two partial wing bones of a ptarmigan (Willow most likely; Lagopus lagopus) or a grouse, and a 

partial wing bone of a passerine (songbird; Passeriformes sp.). 

Jonathan Fiely, on the staff of the University of Alaska Museum of the North’s Mammology Department, 

examined the microtine mandibles and cranial dentition, as studies have found that differences in dentition 

patterning can be used to differentiate the remains to genus and even species level. Comparative collections 

from UAM’s Mammology Department were used. No attempt was made to identify other, post-cranial microtine 

faunal remains to genus or species. A total of 27 microtine mandibles and cranial dentition was indentified, 

including various voles (Microtus sp.; n=19), the North American Brown Lemming (Lemmus trimucronatus; 

n=2), an unidentified lemming (Lemmus sp.; n=1), and the Northern Red-Backed Vole (Clethrionomys rutilus; 

n=5). In addition, one snowshoe hare (Lepus americanus) distal femur was identified from the test pit. No 

radiocarbon dates have been run on any materials from this test pit. 

Karst Feature #37

The test in this small cave, which was 10 m in maximum width by 4.0 m in maximum depth, measured 30 cm 

in depth. A relatively few bird and microtine mammal bones were found “near the base” of this test pit. The 

stratigraphy, from top to bottom, was described by the excavators as a uniform, largely non-organic silt. Only 

one bone from the test pit was identifiable: a leg bone of a Rock Ptarmigan (Lagopus muta). No radiocarbon 

dates have been run on any materials from this test pit.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

34

Karst Feature #46

Karst Feature #46 – Description, by Robin O. Mills and Robert Sattler

This small “cave” or rockshelter is a fissure-expanded frost pocket that is sheltered above by a limestone 

outcrop (Figures 28-31). The shelter is relatively flat on the bottom and has a back chimney that rises to a 

small ledge approximately 3.5 m above the shelter floor. The chimney is not large enough for a person to climb 

through, but it appears that small animals can scamper onto a ledge that is up the chimney, which is 1 x 0.5 m 

in size (see hole above person’s head in Figure 28). This same ledge also can and likely does serve as a raptor 

perch. Surface bones indicate that the same depositional processes that are occurring today also occurred in 

the past, as evinced from the abundant faunal remains found in the tests placed in this feature (see below). The 

surface bones include microtine mammal remains and a couple of metal-sawn medium-large mammal (e.g., 

sheep, caribou) bone fragments. 

The interior of the shelter is intensively fractured and small clasts can be taken off of the wall in most of the 

shelter interior. Moss, and black and light green lichen grow on portions of the interior walls. Small circular 

vesicles appear along the limestone outcrop above the cave, as well as small solution pockets at the top of the 

chimney. Circular white lichens grow on the rock outcrop in abundance and are generally 1-5 cm in diameter. 

The inside texture of the limestone is very sharp; scalloped solution fractures on the interior surface are 

indicative of active spalling. However, there are in some places small popcorn speleothem growths indicating 

at least some degree of stability on some of the interior surface.

Figure 32 presents the floor plan of this small cave. The karst feature has an average width of about 50-60 cm 

and a maximum depth into the limestone of 2.2 m. The width at the mouth is about 1.2 m, and the height of the 

opening measures 2.5 m. About a meter in front of the dripline, the ground surface begins to drop in elevation. 

By about 2.5 meters in front, the increasing descent turns into a near-vertical drop of about 3-4 meters (Figure 

29).

The original circa 45 x 60 cm test pit dug in 2003, placed at the dripline, uncovered hundreds of small bones 

from top to bottom (see Figures 31-32 for placement of the test pit). Most of the bones comprised birds 

and microtine mammals, but also included a few small fragments of larger bones from medium-large sized 

mammals (e.g., sheep and caribou-sized animals), as well as a few fish bones and even some mollusk remains. 

Many bones were picked out of the back dirt of the two main stratigraphic units that were recognized by the 

original surveyors in 2003 (i.e., an upper dark brown organic layer, and a lower gray layer). As mentioned 

above, one owl pellet and an assortment of small bones on the surface or floor of this feature indicate the 

droppings and meal remains of contemporary carnivorous birds and maybe small carnivorous mammals. It is 

likely that the same biological processes that resulted in these present-day surface remnants also occurred in 

the past, as exposed in the test pit. 

Because of the rich nature of these deposits discovered in 2003, Alaskan quaternary paleontologist Robert 

Sattler and I returned to this cave in 2005, where we re-excavated the northern portion of the 2003 test 

pit. We screened all of the removed backfill from this test through a 1/8” mesh and collected two bags of 

faunal material: one bag of microtine mandibles and one bag of miscellaneous bones (i.e., avian; post-cranial 

microtine; small fragments of larger mammal bones). In addition, we also excavated a 13 x 20 cm column off 

of the north side of the original test (i.e., on the side away from the rear of the cave; Figure 33), and collected 

bulk matrix samples (soil and rock) and all faunal remains from the column in arbitrary increments within the 

three natural Stratigraphic Units noted in the column profile (see below). Although bedrock was not reached, 

excavation ceased when the blocky roof fall at the bottom of the pit became too large to excavate through with 

trowels. 
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

35

Figure 28. Karst Feature #46, immediately to the right of Robert Sattler, center of photo; Limestone Gulch region, WMNRA. Note the small cave or rock shelter is immediately right of Sattler, and the raptor perch above his head that, through a chimney, drops in to the back of the cave.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

36

Figure 29. The steep slope directly in front of Karst Feature #46; Limestone Gulch region, WMNRA.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

37

Figure 30. Karst Feature #46; Limestone Gulch region, WMNRA. Note the trowels in the ground in front of the 

mouth, for scale. The trowel with the brown wooden handle is centered in the test pit excavated in 2003. 
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

38

Figure 31. Floor of Karst Feature #46; Limestone Gulch region, WMNRA. The trowel with the brown wooden 

handle is centered in the test pit excavated in 2003. The distance from the red-handled trowel to the back 

wall of the cave is only 2 meters.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

39

Figure 32. Floor plan view of Karst Feature #46 and area immediately to the north; Limestone Gulch 

region, WMNRA. 
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

40

Figure 33. Karst Feature #46; Limestone Gulch Region, WMNRA. Robert Sattler in 2005 excavating a 

13x20cm column off of the original 2003 test pit in this cave.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

41

In our 2005 excavation column, we tried to excavate and collect using an arbitrary increment of 5 cm within 

the natural stratigraphy seen in the profile. This was largely successful in the upper part of the column, but 

became untenable the deeper we dug owing to the large, blocky nature of the rocks encountered, which 

accounted for most of the matrix in the lower portion of the pit. Thus, nine sample bags from this column were 

collected: Bag/Sample 1: 0-5 cm, Sample 2: 6-10 cm, Sample 3: 10-11 cm, Sample 4: 11-16 cm, Sample 5: 16-

21 cm, Sample 6: 21-26 cm, Sample 7: 26-31 cm, Sample 8: 31-42 cm, Sample 9: 42-45 cm. As above, faunal 

materials and regurgitated owl pellets on the surface or floor of the cave from relatively recent biological 

activity were also collected, along with the faunal material screened from the backfill of the 2003 test pit.

Figures 34-35 present the stratigraphic profile of this excavated column. Three main Stratigraphic Units were 

described based upon the exposed 2005 excavated column profile: 

Stratigraphic Unit 3

Figure 34. Stratigraphic profile of test pit column 

excavated in 2005 in BLM Karst Feature #46; Limestone 

Gulch region, WMNRA. The column, excavated off of the 

side of the 2003 test pit, is 20 cm wide and 45 cm deep.

Stratigraphic Unit 1

Stratigraphic Unit 2

Unit 1: 0-11 cm; includes Sample 1 (0-5 cm), 

Sample 2 (6-10 cm), and Sample 3 (10-11 cm); 

organic rich soil; dark brown organic breccia, 

organic silt with small angular stones; the sediment 

in Sample 3 contains more dense granules than the 

overlying 10 cm; although small animal bones 

were noted throughout the unit, they increase 

dramatically in Sample 3.

Unit 2: 11-26 cm; includes Sample 4 (11-16 cm), 

Sample 5 (16-21 cm), and Sample 6 (21-26 cm); 

less organic soil; dark gray breccia, silt/sand with 

larger lithic blocks (largest ca. 6-8 cm) than Unit 

1; very abundant granules; abundant small animal 

bones were noted throughout the unit; the basal 

level (21-26 cm) is considerably more blocky, and 

seemingly more clayey than the rest of the unit; the 

boundary between Unit 2 and Unit 3 is a textural 

change.

Unit 3: 26-45cm; includes Sample 7 (26-31 cm), 

Sample 8 (32-42 cm), and Sample 9 (42-45 cm); 

seemingly more organic brown soil than Unit 

2, more and larger limestone clasts and blocks, 

relative to Unit 2; a distinctive zone of clayey 

fine-grained fill is noted at 26-31 cm, with much 

less clasts and blocks relative to the remainder of 

the unit; below 31 cm there is a mass of relatively 

loose, unstable rubble with much less interstitial 

fine-grained sediment between the blocks; although 

small animal bones were noted throughout the unit, 

an increased abundance of them was noted at the 

base of the unit at 42-45 cm, relative to the rest of 

the unit; the spaces in between the larger blocks in 

this 42-45 cm level is dominated by small pebbles 

(1-2 cm) with very little fine interstitial sediment. 
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

42

Figure 35. Schematic stratigraphic profile of test pit column excavated in 2005 in BLM Karst Feature #46; 

Limestone Gulch region, WMNRA. 

Legend

35

0

5

10

15

20

25

30

Depth

(cmBS)

40

45

Stratigraphic

 Units

Excavation

 Levels

silty sand

organic

silt

limestone

blocks

Level 1

Level 2

Level 4

Level 5

Level 6

Level 7

Level 8

Level 9

0 10 20 cm

Level 3

Unit 1

Unit 2

Unit 3

3a

3b
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

43

Karst Feature #46 – Radiocarbon Dating

Four bone samples from the 2005 excavated column were submitted for radiocarbon dating, the results of 

which are provided in Table 2. Bone collagen was the material dated, and all assays are AMS (accelerator 

mass spectrometry) dates. The dating attempted to focus on the major natural stratigraphic breaks that were 

recognized in the field, those at 11 cm and 26 cm below the surface (see “Karst Feature #46 – Description”, 

above). Thus, Beta-263573 was run on a bone from the 10-11 cm arbitrary level (Cal BP 3560), Beta-263574 

came from the 21-26 cm level (Cal BP 9550), Beta-263575 came from the 26-31 cm level (Cal BP 7460), and 

Beta-263576 came the bottom-most 42-45 cm level (Cal BP 7600). 

Although dating will be discussed further, below (“Karst Feature #46 – Discussion”), several things are 

immediately apparent from a quick perusal of the four dates. First and most obvious is the reversal witnessed 

with Beta-263574 (Cal BP 9550) from the 21-26 cm arbitrary level. As it is about 2000 years older than the 

date from the bottom-most 42-45 cm arbitrary level, and seeing as how there is no obvious reason to discount 

this AMS assay, it is reasonable to assume that some degree of mixing has occurred within these deposits in 

the past. An obvious candidate(s) for this mixing is past scraping or burrowing by animals, such as foxes, 

wolves, coyotes, or sheep. The degree of mixing or disturbance is presently impossible to extrapolate to the 

remainder of the cave’s buried deposits.

Second, the two lower dates, Beta-263575 (Cal BP 7460) and Beta-263576 (Cal BP 7600), at the top and 

bottom of Unit 3, respectively, might at first appear to be too close together to account for nearly half of the 

buildup of the deposits in the stratigraphic profile. A closer examination of the profile, however, indicates what 

might be a rapid roof fall deposition event that accounts for most of Unit 3. If this mass of rubble actually 

represents a relatively rapid, in situ roof fall event (and not, say, a mound of pushed up debris from animal 

burrowing), then the two dates’ closeness make sense and would, in fact, be anticipated.

And third, with the acceptance of Beta-263574 (Cal BP 9550) as a legitimate, non-contaminated date, albeit 

apparently displaced, then it would seem that most if not the entire Holocene record is represented in this 

cave’s deposits.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

44

Beta ID Sample 

Depth (cm)

Sample Measured 

Radiocarbon Age BP

13C/12C Ratio (o/oo)

Conventional Radiocarbon Age BP*

Calibrated Intercept Date BP

Calibrated 1 Sigma (68%) BP

Calibrated 2 Sigma (95%) BP

263573 10-11 Small bone fragment; 

outer cortex of the bone of a small-medium sized mammal (~fox-caribou) or large bird; 0.24 g

3250 +/- 40 -20.8 3320 +/- 40 3560 3480-3600 3450-3640

263574 21-26 Same as Beta 263573; 0.56 

g

8560 +/- 50 -21.4 8620 +/- 50 9550 9540-9560 9530-9680

263575 26-31 Same as Beta 263573, 

except bone fragment from a wolf-sheep-caribou sized animal; 1.99 g

6510 +/- 40 -21.4 6570 +/- 40 7460 7430-7500 7420-7560

263576 42-45 Same as Beta 263573; 0.39 

g

6690 +/- 50 -20.7 6760 +/- 50 7600 7580-7660 7560-7680

Table 2. Radiocarbon dates from Karst Feature #46.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

45

Karst Feature #46 - Carbon Content and Pollen Analysis, by Nancy H. Bigelow 

and Robin O. Mills

Carbon Content and Pollen Analysis: Introduction and Methods

Nine samples collected from just inside the drip line of a BLM Karst Feature #46 were sub-sampled and 

analyzed for carbon content and pollen (see Karst Feature #46 – Description; above): Bag/Sample 1: 0-5 cm, 

Sample 2: 6-10 cm, Sample 3: 10-11 cm, Sample 4: 11-16 cm, Sample 5: 16-21 cm, Sample 6: 21-26 cm, 

Sample 7: 26-31 cm, Sample 8: 31-42 cm, Sample 9: 42-45 cm.

Carbon content was measured using Loss-On-Ignition (LOI), a technique that burns samples at 550° C and 

850° C to measure organic and inorganic carbon, respectively. Prior to the analysis, the samples were dried 

for 60 hours in an oven at 85° C. The dried samples were then weighed before and after the burns, the weight 

loss indicates the amount of carbon in the sample.

% organic carbon = ((A-B)/A)*100

Where: A = dried sample weight (in grams)

B = sample weight after 550° C burn (in grams)

% inorganic carbon (as CaCO3) = ((B-C)/A)*100*0.44

Where: A = dried sample weight (in grams)

B = sample weight after 550° C burn (in grams)

C = sample weight after 800° C burn (in grams)

Sub-samples for pollen analysis were processed using standard techniques (sieving, 10% KOH, and 10% 

HCl washes) followed by heavy liquid separation (s.g. 2.0) and filtered with a fiberglass filter. The filter 

was then dissolved in hydrofluoric acid, the sample acetolized (2 minutes in a boiling water bath with acetic 

anhydride and sulfuric acid), washed in glacial acetic acid and water, and suspended in silicone oil (Faegri and 

Iversen, 1989; Moore et al., 1991). Pollen identifications were based on comparisons with published atlases 

(McAndrews et al., 1973; Moriya, 1976; Moore et al., 1991) and with the pollen reference collection housed 

at the Department of Geology and Geophysics at the University of Alaska Fairbanks.

Carbon Content and Pollen Analysis: Results and Discussion

Loss-On-Ignition of Karst Feature #46. Table 3 and Figure 36 present the results from the LOI analysis, with 

data provided by excavated level. Appendix 4 contains the raw LOI data. Samples collected within 11 cm 

(Stratigraphic Unit 1) of the surface had relatively high percentages of organic carbon (ca. 20-35%). Samples 

collected lower in the section (Stratigraphic Units 2 and 3) had much lower organic carbon content, about 

10-15% or less. The relatively high organic carbon near the surface probably reflects both soil formation and 

perhaps wind deposition of plant material from outside of the rock shelter.

In contrast to the organic carbon, the inorganic carbon (as CaCO3) has the opposite distribution, with the 

lowest amounts in the top of the section (13%), reaching to more than 60% by the base. This pattern probably 

reflects a combination of carbonate dissolution from the surface sediments and redeposition deeper in the 

section and primary deposition of lithologic carbonate (i.e., rock spall) and bones within the section. The 

sieved fraction (>= 250 micron) of the pollen subsamples contain both bone and carbonate fragments from 

10 cm and lower. Sub-samples from the top 10 cm contain primarily organic debris, with minor amounts of 

lithologic carbonate.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

46

Table 3: Carbon content of samples from Karst Feature #46 (measured as loss-on-ignition), by excavated 

level.

Statigraphic 

Unit

Sample

depth

(cm)

Organic

Carbon

(%)

Inorganic

Carbon

(%)

Unit 1 0-5 35.6 13.6

5-10 28.2 20.6

10-11 20.1 30.7

Unit 2 11-16 13.0 45.8

16-21 14.2 40.0

21-26 12.0 44.5

Unit 3 26-31 12.6 42.2

31-42 11.2 53.0

42-45 7.4 61.4

Figure 36. Carbon content of samples from Karst Feature #46 (measured as loss-on-ignition).

The LOI raw data for the individual levels were added together per Stratigraphic Unit (see Karst Feature #46 

– Description, above), and the organic carbon and inorganic carbon percentages were recalculated. Figure 

37 presents these results, which serve to highlight more clearly the data trends observed above regarding the 

decreasing amounts of organic carbon, and increasing amounts of inorganic carbon, found in the excavated 

column with increasing depth.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

47

Pollen Analysis. Appendix 5 contains the raw pollen data and percentages, both by excavation level and 

Stratigraphic Unit. Figure 38 presents all of the pollen and spore results by excavation layer, while Figures 39-

40 focus specifically upon the pollen producers, with data grouped by Stratigraphic Unit. Pollen percentages 

in this analysis are calculated on two pollen sums. The percentages of trees, shrubs, and herbs are based on 

the sum of those taxa. This is the basic pollen sum. The percentages of all spore-producers are calculated on 

the sum of the spore-producers PLUS the sum of the trees, shrubs, and herbs. The reason for the two sums 

is to prevent the spore-producers from overwhelming the trees, shrubs, and herbs in the percent calculation.

Overall, the pollen and spore preservation in these samples was marginal. This is due to two main factors: 

mechanical wear on the pollen and spores during and after deposition, and repeated wetting and drying of the 

samples in a basic environment. Sporopollenin (the material forming the grain walls) is sensitive to high pH 

and most of the grains are somewhat- to highly degraded. The high indeterminable counts (up to nearly 40 

per 100 identifiable tree, shrub, and herb grains) are due to this mechanical and chemical wear on the grains. 

On the whole, the pollen samples were difficult to count and for this reason the pollen counts stopped when at 

least 100 tree, shrub, and herb pollen grains were encountered.

The pollen results indicate that birch (Betula) and alder (Alnus) have been abundant in the region and were 

probably growing locally at Karst Feature 46 for the depositional history of the sediments. Salix is present 

but uncommon around the feature today, and the pollen data suggests this has been the case throughout the 

Holocene.

The spruce (Picea) pollen presents an interesting history, with its apparent local arrival within Stratigraphic 

Unit 1 (0-11 cm below surface). The consistent but low percentages (<10%) of spruce below Stratigraphic 

Unit 1 suggests it was growing in the region, but probably wasn’t present right at the rock shelter. The postglacial expansion of spruce in the interior dates to about 8000 to 9000 radiocarbon years ago (Anderson et 

Figure 37. Carbon content of samples from Karst Feature #46 (measured as loss-on-ignition), by 

stratigraphic Unit.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

48

al., 2004). Whether the spruce rise at Karst Feature #46 reflects the postglacial spruce expansion or whether 

spruce was a late arrival at the site is still unclear. However, a pollen analysis at Oops Lake on lower Fossil 

Creek in the White Mountain National Recreation Area (Finney and Krumhardt, 2004), only 3.7 miles (6 

km) southwest of Karst Feature #46, suggests that spruce wasn’t locally present there until after about 4800 

radiocarbon years ago. These data are re-enforced by the Karst #46 data, where the base of Stratigraphic Unit 

1 has provided a date of 3320 radiocarbon years ago (see Karst Feature #46 – Radiocarbon Dating, above). 

The spore-producers provide additional insight into the vegetation around Karst Feature #46. For example, the 

spike moss (Selaginella selaginoides) prefers moist and open ground, especially calcareous soil.

The ferns are the most unusual aspect of the spore-producers. Fern spore frequencies in Holocene-aged lake 

cores of interior Alaska are rarely greater than 10% (Ager, 1975; Hu et al., 1993; Bigelow and Edwards, 

2001). In fact, the fern frequencies seen in Karst Feature #46 are more similar to sites in southern Alaska, 

especially during the early Holocene (Peteet, 1991; Hu et al., 1995; Cwynar, 1990; Ager, 2000).

The high frequency of fern spores in the samples from Karst Feature #46 is partly explained by the difference 

in pollen depositional mechanisms in terrestrial sediments versus in lakes. The spores and pollen preserved 

in lakes reflects a higher proportion of the regional vegetation than they do in terrestrial sediments (Jacobson 

and Bradshaw, 1981). The reason is lakes collect pollen from inlet streams, surface run-off, and from the air. 

In contrast, the pollen preserved in Karst Feature #46 is mainly from the air, and perhaps from some internal 

run off. As a result, the pollen and spore data reflect a relatively high proportion of the vegetation growing just 

outside the rock shelter. After looking at photographs karst feature made during site visits, it appears that ferns 

are abundant at the entrance to the rock shelter today. The spore analysis indicates they have been growing 

there for the duration of sedimentation in the rock shelter, which according to the radiocarbon data seems to 

span most of the Holocene. While ferns are a diverse group of plants, all ferns prefer moist settings, indicating 

that water has not limited the vegetation at the rock shelter.

Lastly, a few Encalypta-type and Botrychium spores were also noted in some samples. Encalypta today is 

found on dry open settings while most Botrychium species are found on grassy slopes (Hultén, 1968; Brubaker 

et al., 1998); both probably grew (and perhaps do today) just outside the rock shelter.

The pollen analysis suggests the vegetation around the rock shelter was mainly a birch and shrub tundra with 

spruce trees present in the latter part of the record. The cave entrance has probably been well-covered by ferns 

for a long time, and the abundance of spores in general suggest water has been at least locally abundant for the 

duration of sediment deposition.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

49

05

1015202530354045

Depth (cm)

20 20 40 20 40 20 40 60 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 20 40 3 20 40 60 3 3 3

100164122124213115121160145

252835343614151433

107115123109111107135120114

280522531422505467594592456

Picea glauca-type Picea mariana-type Picea undiff. BetulaAlnus Salixcf. Shepherdia Arctostaphylos-type Ericales undiff. cf. Rosaceae undiff. Artemesia Saussurea Tubuliflorae undiff. Caryophyllaceae undiff. Brassicaceae Cyperaceae Poaceae cf. Liliaceae Lycopodium annotinum Lycopodium clavatum Lycopodium complanatum Lycopodium selago Lycopodium undiff. Selaginella selaginoides Botrychium Sphagnum Trilete undiff. Monolete undiff. Monolete rugulate Monolete verrucate Encalypta Monolete aberrant Indeterminable Pollen sum Pollen sum & Spore-producers

Trees and Shrubs Subshrubs, Herbs, and Forbs Lycophyta Ferns

Basic Pollen Sum Pollen Sum and Spore-producers

Analysis by NH Bigelow

8

BLM Karst Feature 46Pollen percentage diagramOctober 27, 2006

Figure 38. Pollen and spore percentage diagram for Karst Feature #46. Note scale changes with the minor taxa. See text for explanation of percent calculations.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

50

Intentionally Left Blank
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

51

Karst Feature #46 – Mammalian Faunal Remains

Hundreds of skeletal elements of mammals were excavated from both the original 45 x 60 cm test pit dug in 

2003, and the subsequent 13 x 20 cm column excavated in 2005. Bags of fauna from the 2003 test pit were 

collected from the two gross stratigraphic layers recognized by the excavators at that time: (1) an upper dark 

brown organic soil, corresponding to Stratigraphic Unit 1 (described above), and (2) from all of the underlying 

dark gray silt and jumbled limestone blocks below that layer, corresponding to Stratigraphic Units 2 and 3. 

Bags from the 2005 column, as explained above, were excavated, when possible, by 5 cm arbitrary levels 

within the three naturally occurring Stratigraphic Units that were recognized in the field. Because the 2005 

material was excavated in a more controlled manner, I decided to focus our efforts on the faunal remains 

obtained from this column.

The overwhelming majority of the mammal bones from the column (and from the larger 2003 test pit, for 

that matter) are from microtine mammals. Jonathan Fiely, on the staff of the University of Alaska Museum 

of the North’s Mammology Department, examined the microtine mandibles and cranial dentition, as studies 

have found that differences in dentition patterning can be used to differentiate the remains to genus and even 

species level. Comparative collections from UAM’s Mammology Department were used. No attempt was 

made to identify other, post-cranial microtine faunal remains to genus or species. The results are found in 

Table 4, and illustrated in Figure 40.

Figure 39. Pollen percentage diagram for Karst Feature #46, for trees and shrubs only, by Stratigraphic 

Unit. See text for explanation of percent calculations.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

52

In total, 118 cranial and mandibular dentition sets were identified to either genus or species. The majority 

(74; 63%) could only be identified to the genus Microtus spp. (i.e., an assortment of voles). Other identified 

species include the Northern Red-Backed Vole (Clethrionomys rutilus) (30; 25%), the North American Brown 

Lemming (Lemmus trimucronatus) (13; 11%), and the Northern Bog Lemming (Synaptomys borealis) (1; 

1%). 

For purposes of discussion, I will assume several things in regards to the microtine data. (1) I will assume that 

most if not all of the remains are the results of meals from, most likely, raptors roosting above the rockshelter 

floor (see Karst Feature #46 – Description, above). This process continues today, as a host of small animal 

bones and one owl pellet were found on the present-day surface, along with bird whitewash on the walls. (2) I 

will assume that predators have grabbed a representative sample of microtines from the landscape surrounding 

the vicinity of Karst Feature #46 over time. (3) I will assume that the deposits are not overly mixed from past 

taphonomic activities, so that they retain some measure of stratigraphic integrity. (4) I assume that my sample 

size is large enough to be representative of past dynamics. In sum, if we assume these conditions, then there 

appears to have been little change in the microtine species composition in the general vicinity of Karst Feature 

#46 over most of the Holocene. 

By combining the data from the separate excavation levels into the three Stratigraphic Units outlined above 

(Figure 41), the data may indicate an increased presence of Lemmus trimucronatus and Clethrionomys rutilus

relative to the Microtus species during the latter part of the Holocene. Here, we see the percentage of Microtus

in the samples dropping from 66% and 62% of samples in Stratigraphic Units 2 and 3, to 50% of the samples 

in Stratigraphic Unit 1. Unfortunately, the numbers of identified specimens in Stratigraphic Unit 1 is quite 

small (n=15), and may not be statistically reliable.

Table 4. Identified microtine cranial and mandibular dentition from the soil column excavated in Karst Feature 

#46 in 2005, by excavation level (NISP). (*Includes one Microtus oeconomus, or the Tundra or Root Vole. All 

remaining Microtus remains were identified as Microtus spp.).

Microtus

(various 

voles)

Lemmus 

trimucronatus

(North American 

Brown 

Lemming)

Clethrionomys 

rutilus

(Northern RedBacked Vole)

Synaptomys 

borealis

(Northern 

Bog 

Lemming)

Surface 1 1

0-5 cm 1 1 1 3

5-10 cm 5* 3 1 9

10-11 cm 1 1 2

11-16 cm 14 5 4 23

16-21 cm 9 5 14

21-26 cm 12 4 16

26-31 cm 8 1 4 13

31-42 cm 10 2 4 16

42-45 cm 13 1 6 1 21

74 13 30 1 118
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

53

Figure 41. Identified microtine cranial and mandibular dentition from the soil column excavated in Karst 

Feature #46 in 2005, by stratigraphic Unit (percentages).

Figure 40. Identified microtine cranial and mandibular dentition from the soil column excavated in Karst Feature 

#46 in 2005, by excavation level (percentages).

The known range of all present species of Microtus in Alaska includes the White Mountains, except for the 

St. Matthew Island Vole (Microtus abbreviates) which is found only on Hall and St. Matthew islands in the 

Bering Sea. These others include the Long-tailed Vole (Microtus longicaudus), the Meadow Vole (Microtus 

pennsylvanicus), the Singing Vole (Microtus miurus), the Tundra Vole (Microtus oeconomus), and the Yellowcheeked Vole (Microtus xanthognathus). The ranges of each of these species are quite widespread and found 

throughout large swaths of North America or around the circumpolar north, and found in a diverse array of 

ecological niches and habitats (http://www.iucnredlist.org; http://en.wikipedia.org).
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

54

Lemmus trimucronatus is found throughout the entire interior of Alaska and the North Slope, inhabiting arctic 

tundra or subarctic alpine tundra above tree line. It is also a widespread species, found throughout much of 

northern North America and Asia. Similarly, Clethrionomys rutilus is found all over the interior of Alaska, 

excepting the extreme North Slope well above the Brooks Range, and is typically found in northern shrub 

vegetation, most forest types found in the Alaskan interior, tundra settings, as well as rock fields and talus 

slopes. Last, Synaptomys borealis is found throughout most of central interior Alaska, much of Canada, and 

into the northern United States, inhabiting wet northern forests, bogs, tundra and meadows (http://www.

iucnredlist.org; http://en.wikipedia.org).

Even if the decrease in relative amount of Microtus during the late Holocene is an accurate reflection of past 

biological populations, the habitats of most if not all of the species found in the test unit largely overlap. 

For instance, it is not as if some microtines only inhabit ranges that today are found north of, or south of, 

their present-day range. Such data would indicate different landscape conditions than those found today. 

Unfortunately, that does not appear to be the case. The microtine data presented here appear to be too coarsegrained to serve as a proxy for assessing ecological changes throughout the Holocene. 

In addition to microtines, other mammalian faunal remains were found in the 2003 test pit and 2005 column. 

The majority of these are small, unidentified long bone shaft fragments derived from unidentified mediumlarge sized mammals (e.g., sheep, caribou) of unknown maturity. Such fragments were used to procure the 

radiocarbon assays for this rockshelter. In addition, two elements were extracted from in situ deposits in the 

sidewall of the 2005 excavated column: (1) a complete tooth with root of either a marten (Martes Americana)

or mink (Mustela vison) was found at 22 cm below surface, and (2) a distal portion of a second phalanx of a 

caribou (Rangifer tarandus) was found at 29 cm below surface. 

Karst Feature #46 – Avian Faunal Remains

Hundreds of skeletal elements of birds were excavated from both the 2003 test pit and the 2005 13 x 20 cm 

column, in the same manner as described above for the mammalian fauna. As above, I decided to focus our 

efforts on the avian remains from the tightly controlled column excavated in 2005. Dr. Kevin Winker, Curator 

of Ornithology at University of Alaska Museum of the North, examined the bird remains, comparing them 

to UAM’s bird faunal collections. Many remains could not be identified to genus or species owing to the 

fragmentary nature of the assemblage, and to the fact that some avian skeletal elements have not been found 

to be diagnostic to species. The results are found in Table 5.

All of the identified remains, with the exception of one bone, come, or likely come from only three prey 

species: Rock Ptarmigan (Lagopus muta), Spruce Grouse (Falcipennis canadensis), and Ruffed Grouse 

(Bonasa umbellus). The sole exception is a tarsometatarsus of a Northern Hawk Owl (Surnia ulula) found 

in excavation level 10-11 cm, at the bottom of Stratigraphic Unit 1. The ptarmigan and grouse elements are 

found throughout the column, in no apparent pattern of increasing or decreasing occurrence. Based upon the 

avian and the radiocarbon data, little more can be said except that ptarmigan and grouse were available and 

fed upon for much of the Holocene in the general area of Karst Feature #46.
Stratigraphic Unit Excavation Level ABSR No. ID Scientific Name

Unit 1 0-50 cm 5 “hand” bone of a ptarmigan Lagopus sp.

Unit 1 0-50 cm 6 “hand” bone of a ptarmigan Lagopus sp.

Unit 1 0-50 cm 8 partial coracoid of a ptarmigan (probably) or a Ruffed Grouse Lagopus sp. or Bonasa umbellus

Unit 1 5-10 cm 7 metacarpal bone of a ptarmigan or Spruce Grouse Lagopus sp. or Falcipennis canadensis

Unit 1 5-10 cm 9 partial femur of a ptarmigan (probably) or a grouse Lagopus sp. or Falcipennis or Bonasa

Unit 1 5-10 cm 10 partial tarsometatarsus of a Spruce Grouse or possibly Ruffed Grouse Falcipennis canadensis or Bonasa umbellus

Unit 1 5-10 cm 11 part of an ulna of a galliform, probably ptarmigan but could be Ruffed Grouse Lagopus sp. or Bonasa umbellus

Unit 1 5-10 cm 12 “hand” bone of a ptarmigan Lagopus sp.

Unit 1 5-10 cm 13 upper end of a leg bone of a grouse or ptarmigan Falcipennis or Bonasa or Lagopus

Unit 1 5-10 cm 14 tip of a lower mandible of a grouse or ptarmigan Falcipennis or Lagopus

Unit 1 5-10 cm 15 “hand” bones of a galliform, likely a ptarmigan (mni = 2) Lagopus sp.

Unit 1 10-11 cm 2 tarsometatarsus of a Northern Hawk Owl Surnia ulula

Unit 1 10-11 cm 3 “hand” bone of a ptarmigan or grouse Lagopus sp. or Falcipennis canadensis

Unit 1 10-11 cm 4 “hand” bone of a galliform, probably ptarmigan but possibly a grouse Lagopus sp. or Falcipennis or Bonasa

Unit 2 11-16 cm 16 distal end of a fibula of a grouse or ptarmigan Lagopus sp. or Falcipennis canadensis

Unit 2 16-21 cm 17 partial pelvis of a ptarmigran or grouse Lagopus sp. or Falcipennis canadensis

Unit 2 16-21 cm 18 partial leg bone of a grouse or ptarmigan Bonasa umbellus or Lagopus sp.

Unit 2 21-26 cm 19 partial leg bone of a ptarmigan (probably Rock) or, less likely, a Spruce Grouse Lagopus muta (probably) or Falcipennis canadensis

Unit 2 21-26 cm 20 tarsometatarsus of a ptarmigan, probably Rock Ptarmigan Lagopus muta (probably)

Unit 2 21-26 cm 21 partial leg bone of a grouse or ptarmigan (closest to Ruffed Grouse) Bonasa umbellus or Lagopus sp.

Unit 3 26-31 cm 22 leg bone of a ptarmigan, probably Rock Ptarmigan Lagopus muta

Unit 3 26-31 cm 23 partial lower mandible of a ptramigan or grouse Lagopus sp. or Falcipennis or Bonasa

Unit 3 31-42 cm 24 partial coracoid of a ptarmigan or grouse; closest to Rock Ptarmigan Lagopus muta (probably) or Falcipennis or Bonasa

Unit 3 31-42 cm 25 partial carpometacarpus (wing bone) of a Spruce Grouse or a ptarmigan Falcipennis or Lagopus

Unit 3 31-42 cm 26 partial ulna (wing bone) of a ptarmigan, probably Willow Ptarmigan Lagopus lagopus (probably) or a large L. muta

Unit 3 42-45 cm 27 partial distal wing bone of a ptarmigan or grouse Lagopus sp. or Falcipennis or Bonasa

Unit 3 42-45 cm 28 partial distal wing bone of a grouse or ptarmigan Bonasa umbellus or Lagopus lagopus

Unit 3 42-45 cm 29 partial tarsometatarsus of a Rock Ptarmigan (probably), or small Willow Ptarmigan or a grouse Lagopus muta (probably) or L. lagopus or Falcipennis or Bonasa

Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

55

Table 5. Identified avian fauna from the soil column excavated in Karst Feature #46 in 2005, by excavation level (NISP). (*Alaska Biological Survey, Inc. Forensic Services, Case 0901).

Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

57

Karst Feature #46 – Other Faunal Remains

In addition to the mammalian and avian skeletal remains discussed above, other faunal remains were 

found in the original 2003 test pit, including two mollusk bivalve shell remains (Dr. Nora Foster; personal 

communication 2011) and a few fish remains. The shell fragments have not been further identified to genus or 

species. The fish elements, including vertebrae, cranial fragments, scales, and a portion of a soft fin ray, were 

identified and examined by Dr. Andres Lopez, Curator of Fishes at the University of Alaska Museum of the 

North in Fairbanks (personal communication 2011). He indicates that the remains likely belong to northern 

pike (Esox lucius). Although a conclusive identification was not possible, he points out that most other Alaskan 

freshwater fishes can be ruled out, and that the remains are definitely not from a species of Pacific salmon. A 

minimum number of only one fish is present.

Karst Feature #96

In the spring of 2001, Tim DuPont, one of BLM’s Outdoor Recreation Planners, found a bone on the inside 

surface of a small cave in Limestone Gulch. The bone is a worn Bison sp. right lunate, or intermediate carpal. 

I identified the bone using mammalian comparative collections at the University of Alaska Museum of the 

North, where the bone is now accessioned (UAMES2009.013.ESCI, Bag 27a). Then-Alaska Quaternary Center 

director and paleontologist Dr. Paul Matheus concurred with this identification (personal communication 

2002), and extracted a sample for dating. The sample was radiocarbon dated in January 2002 by the NSFArizona Accelerator Mass Spectrometry Laboratory, at the University of Arizona, which returned a date of 

13,300 +/-160 (uncal C14 age BP; AA44530; C13 ratio -20, F 0.1909+/-0.0038). This bone dates to about 

15,500-16,000 calendar years BP. DuPont found and returned one other large-mammal bone from the surface 

of the cave in 2001; more on this bone, below. I returned to the cave in July 2002 with quaternary paleontologist 

Robert Sattler for a more detailed description and analysis.

The cave is near the top of the southern-most ridge of the two parallel ridges that form Limestone Gulch. The 

mouth of this nearly directly north-facing cave is 1-2 m wide, and 3-4 m tall. It has a wide view over the valley 

floor in between the two parallel ridges that form Limestone Gulch, although much of this view is partially 

obstructed by a large standing rock down slope from the cave mouth. This cave is a relict solution feature. 

After passing southward through the mouth and into the cave, the area widens into an “antechamber” about 

1.5 m wide (E-W) by about 1.5 m depth (N-S). See Figure 42 for both plan and side views of the cave. The 

floor of the antechamber is covered with loose gravelly roof fall or scree (<1 cm pieces), which forms a 

roughly 10 cm thick layer on the antechamber floor. Underlying the scree is a saturated coarse sandy silt/clay. 

After passing through the mouth, there is a small “side room” off of the antechamber, extending about 2 m in 

length to the ENE, and measuring about 50 cm wide and a maximum of 1 m in height. Scree also covers the 

floor of this “side room”.

After entering the “antechamber”, you can proceed further into the cave, southward, by either crawling under 

or climbing over a rock arch, which leads south into a “back room”. This “back room” measures about 5 m 

in depth/length (N-S), and about 2 m wide at its northern end immediately next to the “arch”. The chamber’s 

floor width tapers to roughly 50 cm at its rear or southernmost extent.

A test pit placed in the middle of the “back room” revealed frozen sediment at a depth of only 5-7 cm below the 

surface, even during the height of the summer. The surface sediments consist of coarse blocks of roof fall and 

breccia that is believed to be backfill from an animal excavation in the fill at the back of the chamber. Below 

this coarse surface deposit is a thin layer of smaller, more sorted pebbles most of which are approximately 

1 cm in diameter. Below the two stratigraphic units of angular blocky limestone clasts is a distinctive silty 
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

58

clay with limestone granules and small pebbles. The upper couple of centimeters of this unit was thawed 

and saturated. This unit was sampled for sediment analysis. While excavating the test pit, Sattler found and 

collected three large-mammal bone fragments on the surface of the coarse blocks of roof fall and reworked 

breccia. One of these three bones is a longbone diaphysis fragment of a left humerus of a Bison sp. The 

remaining two fragments refit with the other bone fragment picked up a year earlier by DuPont in 2001. These 

three bones refit into the proximal portion of a Bison sp. ulna. This identification was made using comparative 

paleontology collections at the University of Alaska Museum of the north, with Dr. Patrick Druckenmiller, 

paleontologist and curator of the Earth Sciences Department at UAM, concurring with this identification.

Beyond the three bones picked up on the surface of the backroom in 2002 was a small trough, and the reverse 

angle of repose of the mound of breccia of this trough indicated to Sattler that the trough was probably 

excavated relatively recently by bears. Further back in the cave the walls of the chamber constrict into a small 

fissure and in this area is residual ice and hoar frost. In the deepest area of the chamber is a carnivore scat, 

some small twigs, and a wood stick all of which were clearly brought into the cave by one of the animals in 

the local fauna.

The identified and dated bison lunate found in 2001 derived from the surface of the “antechamber”. In 2002, 

the scree in this “antechamber” was non-systematically troweled, and eight small fragments (< 5 cm length) 

of unidentified large-mammal bone were found either directly on top of the scree, or else within its uppermost 

three centimeters. No excavation into the lower coarse silt was made in the “antechamber”. These bone 

fragments were collected. As there was evidence of (probably) bear digging in the “back room”, with Bison

sp. bone fragments found on the surface of the loose scree at that locale, it is assumed that the loose surface 

scree and bone fragments from the “antechamber” also derived from this taphonomic activity. Based upon 

this limited data, we feel it is probable that additional late Pleistocene faunal remains are present in this cave’s 

perennially frozen deposits.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

59

Figure 42. Floor plan view and side view of Karst Feature #96; Limestone Gulch region, WMNRA. 
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

60

Karst Feature #102

Although a variety of small mammal and bird bones were found on the surface of a handful of the caves, most 

of these appear to be relatively recent accumulations, and largely the result of present-day raptor feeding and 

roosting. In addition to Karst Feature #96 (see above), one other cave produced a bone found on the surface 

that is possibly hundreds if not thousands of year old. Although it remains undated, a sheep (Ovis dalli dalli) 

metacarpal was located in the rear chamber of Karst Feature #102. This bone was located on top of a small 

backdirt pile immediately adjacent to a small porcupine-excavated pit. Plentiful porcupine scat all around the 

area, along with quills, identified the culprit. Based upon the provenance of the find, we feel confident that the 

porcupine activity dug up the bone from a buried context. 
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

61

Summary of the White Mountains 

Karst Surveys

Between 2002 and 2005, eight surveys were conducted in the Limestone Gulch area of the White Mountains 

National Recreation Area, managed by the Bureau of Land Management’s Fairbanks District Office (Figures 

1-2). In total, about 3,350 acres of limestone peaks, valleys, and slope were thoroughly surveyed for karstic 

features (Figure 3), including caves, rock shelters and natural stone arches. A total of 102 such features were 

located (Figures 4-12), and basic biological, physical/natural, and cultural/paleontological attributes were 

recorded for each locale. These raw data are presented in Appendix 3. A variety of modern and paleontological 

biological samples were collected from some of the features (Appendix 2).

This report briefly outlines the basic findings of the 102 karst features examined. Succinctly, no large cave 

systems were found (e.g., 100s or 1000s of meters in length); in fact, the overwhelming majority of the 

caves and rockshelters that were located (93%, n=71 of 76 measured) had greatest lengths of 15 meters or 

less. Likewise, no “spectacular” speleothem formations, nor any underground hydrological systems, were 

located in any of the caves, which could serve to attract recreational hikers and spelunkers. Similarly, no 

historic or prehistoric cultural resources were encountered during the survey, whether inside the caves or in 

the surrounding landscape.

There is abundant evidence that various animals on the landscape today utilize these karst features for both 

short and long-term shelter. Birds were directly sighted using some of the caves, bird nests were located inside 

some caves or at their entrances, and faunal and pellet evidence of raptor feeding and roosting were present in 

some of the caves. Most of the caves (65%, n=66) had scat and other signs of mammal use, including sheep, 

porcupine, marmot, bear and wolverine, in decreasing frequency. Evidence of bear dens were found in nine of 

the caves examined. Several of the caves were found to contain late Pleistocene and Holocene deposits, and 

hold further paleontological interest.
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

62

Intentionally Left Blank
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

63

References Cited

Ager, T. A. (1975). “ Late Quaternary Environmental History of the Tanana Valley, Alaska.” Ohio State 

University Institute for Polar Studies, Columbus.

Ager, T. A. (2000). Postglacial vegetation history of the Kachemak Bay area, Cook Inlet, southcentral 

Alaska. In “Geologic Studies in Alaska by the U.S. Geological Survey, 1998.” (K. D. Kelley, and L. P. 

Gough, Eds.), pp. 147-165. U.S. Geological Survey Paper 1615. U.S. Geological Survey, Washington.

Anderson, P. M., Edwards, M. E., and Brubaker, L. B. (2004). Results and paleoclimate implications of 

35 years of paleoecological research in Alaska. In “The Quaternary Period in the United States.” (A. R. 

Gillespie, and S. C. Porter, Eds.), pp. 427-440. Elsevier, Amsterdam.

Bigelow, N. H., and Edwards, M. E. (2001). A 14,000 yr paleoenvironmental record from Windmill Lake, 

central Alaska: Lateglacial and Holocene vegetation in the Alaska Range. Quaternary Science Reviews 20, 

203-215.

Brubaker, L. B., Anderson, P. M., Murray, B. M., and Koon, D. (1998). A palynological investigation of 

true-moss (Bryidae) spores: morphology and occurrence in modern and late Quaternary lake sediments of 

Alaska. Canadian Journal of Botany 76, 2145-2157.

Cwynar, L. (1990). A late Quaternary vegetation history from Lily Lake, Chilkat Peninsula, southeast 

Alaska. Canadian Jounal of Botany 68, 1106-1112.

Faegri, K., and Iversen, J. (1989). “Textbook of Pollen Analysis.” John Wiley & Sons, Chichester.

Finney, B., and Krumhardt, A. P. (2004). Sediment, pollen, and charcoal analyses of an unnamed lake 

in the White Mountains Recreational Area, Interior Alaska. Submitted to Jim Herriges, Bureau of Land 

Management, Fairbanks.

Hu, F. S., Brubaker, L. B., and Anderson, P. M. (1993). A 12,000 year record of vegetation change and soil 

development from Wien Lake, central Alaska. Canadian Journal of Botany 71, 1133-1142.

Hu, F. S., Brubaker, L. B., and Anderson, P. M. (1995). Postglacial vegetation and climate change in the 

northern Bristol Bay region, southwestern Alaska. Quaternary Research 43, 382-392.

Hultén, E. (1968). “Flora of Alaska and Neighboring Territories.” Stanford University Press, Stanford, CA.

Jacobson, G. L., and Bradshaw, R. H. W. (1981). The selection of sites for paleovegetational studies. 

Quaternary Research 16, 80-96.

McAndrews, J. H., Berti, A. A., and Norris, G. (1973). “Key to the Quaternary Pollen and spores of the 

Great Lakes Region.” Royal Ontario Museum, Toronto.

Moore, P. D., Webb, J. A., and Collinson, M. E. (1991). “Pollen Analysis.” Blackwell Scientific 

Publications, Oxford.

Moriya, K. (1976). “Flora and Palynomorphs of Alaska.” Kodansha Pub. Co, Tokyo.

Peteet, D. M. (1991). Postglacial migration history of lodgepole pine near Yakutat, Alaska. Canadian 

Journal of Botany 69, 786-796.
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Intentionally Left Blank
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

65

Appendix 1.

Cave/Rock Shelter Inventory Form
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

66

Intentionally Left Blank
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

67
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

68
Limestone Gulch, White Mountains NRA: Natural Cultural, and Biological Karst Reconnaissance, 2002-2005

 69

Collected 

Sample #

BLM 

Karst 

Description UAMES2009.013.

ESCI. Bag #

1 96 Bison sp. lunate; collected from surface of "anteroom" in 2001. 27

2 96 Sediment sample; lower silty clay from test pit.

3 96 Nine large mammal bone fragments from surface & upper 1" loose surface rock of "antechamber". 27

4 96 Three large mammal bone fragments collected on surface of "backchamber". 26

5 96 Sediment sample; lower layer from Test Pit #1.

6 96 Granule sedminent sample; small, fluvially rounded pebbles from surface of rear of main chamber.

7 3 Soil & bones from test pit. 17

8 33 Surface bird bones & 1 feather. 18

9 34 Test pit bones & soil, from the lower 30 cm of this 45 cm deep test pit 19

10 35 One bird bone on surface. 20

11 37 Bones on surface. 21

12 37 Bones found at base of test pit. 21

13 46 Test pit 2003; bones collected from all layers 1

14 46 Test pit 2003; bones collected from Layer 2. 2

15 46 Test pit 2003; bones collected from Layer 3. 3

16 46 Bones and regurgitated pellet from surface surface (2005). 4

17 46 Sample 1 of 9 (0-5 cm bs) of 2005 column test, off of original 2003 test pit. 5

18 46 Sample 2 of 9 (5-10 cm bs) of 2005 column test, off of original 2003 test pit. 6

19 46 Sample 3 of 9 (10-11 cm bs) of 2005 column test, off of original 2003 test pit. 7

20 46 Sample 4 of 9 (11-16 cm bs) of 2005 column test, off of original 2003 test pit. 8

21 46 Sample 5 of 9 (16-21 cm bs) of 2005 column test, off of original 2003 test pit. 9

22 46 Sample 6 of 9 (21-26 cm bs) of 2005 column test, off of original 2003 test pit. 10

23 46 Sample 7 of 9 (26-31 cm bs) of 2005 column test, off of original 2003 test pit. 11

24 46 Sample 8 of 9 (31-42 cm bs) of 2005 column test, off of original 2003 test pit. 12

25 46 Sample 9 of 9 (42-45 cm bs) of 2005 column test, off of original 2003 test pit. 13

26 81 Complete bird skeleton on surface. 22

27 82 Mammal scat. 23

28 87 Mammal longbone fragment on surface at rear of lower-most chamber. 24

29 92 Two mammal longbone fragments from surface, center of cave. 25

30 102 Porcupine-excavated sheep metacarpal. 28

31 46 Faunal material from backdirt of 2003 test pit. Screened through 1/8" mesh in 2005. 15

32 46 Faunal material from backdirt of 2003 test pit. Screened through 1/8" mesh in 2005. 16

Appendix 2. Samples collected and accessioned to the 

University of Alaska Museum of the North, Earth Sciences 

Department (UAMES2009.013ESCI) 

Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

71

Appendix 3. Karst Data 2002-2005 

Database

(Refer to inclosed CD)
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72

Intentionally Left Blank
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

Sample 

depth (cm)

Sample middepthCrucible 

no.

Crucible 

wt.

Cruc. + wet 

sed wt.

wet sed wt. Cruc. + dry 

sed. wt.

dry sed. wt. post 550 sed. wt. + 

crucible wt.

post 550 sed 

wt

%LOI 550 post 850 wt. + 

crucible wt.

post 850 

wt. 

%CaCO3 Oven

0-5 2.5 500 9.274 10.052 0.778 9.693 0.419 9.544 0.270 35.561 9.519 0.245 13.560 Matheus

5-10 7.5 501 9.522 10.176 0.654 9.930 0.408 9.815 0.293 28.186 9.778 0.256 20.611 Matheus

10-11 10.5 502 8.263 9.128 0.865 8.899 0.636 8.771 0.508 20.126 8.685 0.422 30.732 Matheus

11-16 13.5 503 9.469 10.357 0.888 10.144 0.675 10.056 0.587 13.037 9.920 0.451 45.791 Matheus

16-21 18.5 504 8.774 9.743 0.969 9.478 0.704 9.378 0.604 14.205 9.254 0.480 40.031 Matheus

21-26 23.5 505 9.383 10.609 1.226 10.389 1.006 10.268 0.885 12.028 10.071 0.688 44.506 Matheus

26-31 28.5 506 9.861 10.824 0.963 10.550 0.689 10.463 0.602 12.627 10.335 0.474 42.222 Matheus

31-42 36.5 507 9.384 10.709 1.325 10.683 1.299 10.538 1.154 11.162 10.235 0.851 53.013 Matheus

42-45 43.5 508 9.261 11.051 1.790 11.022 1.761 10.892 1.631 7.382 10.416 1.155 61.432 Matheus

Appendix 4. Karst Feature #46, Limestone Gulch Region, WMNRA. Loss-On-Ignition data from 

2005 column excavation
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

Sample Sample 

middepth 

(cm)

Picea 

glaucatype

Picea 

marianatype

Picea 

undiff.

Betula Alnus Salix cf. 

Shephe

rdia

Arctostap

hylostype

Ericales 

undiff.

cf. 

Rosaceae 

undiff.

Artemesia Saussurea Tubulifl

orae 

undiff.

Caryophy

llaceae 

undiff.

Brassica

ceae

Cypera

ceae

Poaceae cf. 

Liliaceae

Lycopodium 

annotinum

Lycopodium 

clavatum

Lycopodium 

complanatum

Raw Number Counts

0-5 cm 2.5 12.0 1.0 39.0 17.0 29.0 4.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.0 3.0 1.0 0.0 3.0 1.0 0.0

5-10 cm 7.5 0.0 0.0 27.0 34.0 45.0 1.0 0.0 0.0 0.0 0.0 0.0 0.0 1.0 1.0 4.0 1.0 1.0 0.0 4.0 1.0 0.0

10-11 cm 10.5 0.0 0.0 13.0 34.0 66.0 2.0 0.0 1.0 0.0 0.0 3.0 0.0 0.0 0.0 2.0 1.0 1.0 0.0 2.0 1.0 0.0

11-16 cm 13.5 0.0 0.0 6.0 34.0 53.0 5.0 0.0 0.0 0.0 0.0 3.0 0.0 2.0 0.0 2.0 0.0 3.0 1.0 11.0 0.0 0.0

16-21 cm 18.5 0.0 0.0 8.0 44.0 48.0 3.0 0.0 0.0 1.0 1.0 1.0 1.0 0.0 0.0 2.0 1.0 1.0 0.0 9.0 1.0 1.0

21-26 cm 23.5 0.0 0.0 4.0 38.0 58.0 2.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.0 1.0 3.0 0.0 19.0 1.0 1.0

26-31 cm 28.5 0.0 0.0 2.0 51.0 69.0 5.0 0.0 0.0 0.0 1.0 2.0 0.0 1.0 0.0 1.0 0.0 3.0 0.0 23.0 5.0 0.0

31-42 cm 36.5 1.0 0.0 2.0 51.0 60.0 1.0 1.0 0.0 0.0 1.0 0.0 0.0 1.0 0.0 0.0 1.0 1.0 0.0 22.0 0.0 2.0

42-45 cm 43.5 1.0 0.0 9.0 42.0 56.0 1.0 0.0 0.0 1.0 1.0 1.0 0.0 1.0 0.0 0.0 1.0 0.0 0.0 9.0 0.0 0.0

Raw Numbers Percentages

0-5 cm 2.5 11.2 0.9 36.4 15.9 27.1 3.7 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.9 2.8 0.9 0.0 1.1 0.4 0.0

5-10 cm 7.5 0.0 0.0 23.5 29.6 39.1 0.9 0.0 0.0 0.0 0.0 0.0 0.0 0.9 0.9 3.5 0.9 0.9 0.0 0.8 0.2 0.0

10-11 cm 10.5 0.0 0.0 10.6 27.6 53.7 1.6 0.0 0.8 0.0 0.0 2.4 0.0 0.0 0.0 1.6 0.8 0.8 0.0 0.4 0.2 0.0

11-16 cm 13.5 0.0 0.0 5.5 31.2 48.6 4.6 0.0 0.0 0.0 0.0 2.8 0.0 1.8 0.0 1.8 0.0 2.8 0.9 2.6 0.0 0.0

16-21 cm 18.5 0.0 0.0 7.2 39.6 43.2 2.7 0.0 0.0 0.9 0.9 0.9 0.9 0.0 0.0 1.8 0.9 0.9 0.0 1.8 0.2 0.2

21-26 cm 23.5 0.0 0.0 3.7 35.5 54.2 1.9 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.9 0.9 2.8 0.0 4.1 0.2 0.2

26-31 cm 28.5 0.0 0.0 1.5 37.8 51.1 3.7 0.0 0.0 0.0 0.7 1.5 0.0 0.7 0.0 0.7 0.0 2.2 0.0 3.9 0.8 0.0

31-42 cm 36.5 0.8 0.0 1.7 42.5 50.0 0.8 0.8 0.0 0.0 0.8 0.0 0.0 0.8 0.0 0.0 0.8 0.8 0.0 3.7 0.0 0.3

42-45 cm 43.5 0.9 0.0 7.9 36.8 49.1 0.9 0.0 0.0 0.9 0.9 0.9 0.0 0.9 0.0 0.0 0.9 0.0 0.0 2.0 0.0 0.0

Raw Number Counts

Strat. Unit 1 (0-11 cm) 12.0 1.0 79.0 85.0 140.0 7.0 0.0 1.0 0.0 0.0 3.0 0.0 1.0 1.0 7.0 5.0 3.0 0.0 9.0 3.0 0.0

Strat. Unit 2 (11-26 cm) 0.0 0.0 18.0 116.0 159.0 10.0 0.0 0.0 1.0 1.0 4.0 1.0 2.0 0.0 5.0 2.0 7.0 1.0 39.0 2.0 2.0

Strat. Unit 3 (26-45 cm) 2.0 0.0 13.0 144.0 185.0 7.0 1.0 0.0 1.0 3.0 3.0 0.0 3.0 0.0 1.0 2.0 4.0 0.0 54.0 5.0 2.0

Raw Numbers Percentages

Strat. Unit 1 (0-11 cm) 3.7% 0.3% 24.3% 26.2% 43.1% 2.2% 0.0% 0.3% 0.0% 0.0% 15.0% 0.0% 5.0% 5.0% 35.0% 25.0% 15.0% 0.0% 0.7% 0.2% 0.0%

Strat. Unit 2 (11-26 cm) 0.0% 0.0% 5.9% 38.0% 52.1% 3.3% 0.0% 0.0% 0.3% 0.3% 18.2% 4.5% 9.1% 0.0% 22.7% 9.1% 31.8% 4.5% 2.8% 0.1% 0.1%

Strat. Unit 3 (26-45 cm) 0.6% 0.0% 3.7% 40.4% 52.0% 2.0% 0.3% 0.0% 0.3% 0.8% 23.1% 0.0% 23.1% 0.0% 7.7% 15.4% 30.8% 0.0% 3.3% 0.3% 0.1%

Appendix 5. Karst Feature #46, Limestone Gulch Region, WMNRA. Raw pollen data from 2005 

column excavation
Limestone Gulch, White Mountains NRA: Natural, Cultural, and Biological Karst Reconnaissance, 2002-2005

Lycopodium 

selago

Lycopodium 

undiff.

Selaginella 

selaginoides

Botrychium Sphagnum Trilete 

undiff.

Dryopteris Monolete 

undiff.

Monolete 

scabrate

Monolete 

verrucate

Monolete 

rugulate

cf. 

Encalyptatype

Monolete 

aberrant

Indetermi

nable

Unknown Exotics 

counted

Trees 

and 

Shrubs

Herbs 

and 

Forbs

Pollen 

sum

SporeproducersUnkown

/Indet

Pollen sum 

& Sporeproducers

2.0 0.0 0.0 2.0 39.0 2.0 1.0 39.0 82.0 1.0 0.0 1.0 100.0 25.0 0.0 37.0 102.0 5.0 107.0 173.0 25.0 280.0

1.0 0.0 2.0 3.0 64.0 3.0 0.0 169.0 141.0 15.0 1.0 0.0 164.0 28.0 0.0 49.0 107.0 8.0 115.0 404.0 28.0 519.0

3.0 0.0 7.0 5.0 87.0 1.0 0.0 194.0 104.0 3.0 0.0 0.0 122.0 35.0 2.0 53.0 116.0 7.0 123.0 407.0 37.0 530.0

3.0 0.0 4.0 1.0 57.0 2.0 0.0 130.0 101.0 2.0 0.0 1.0 124.0 34.0 4.0 53.0 98.0 11.0 109.0 312.0 38.0 421.0

1.0 4.0 5.0 1.0 162.0 0.0 0.0 109.0 100.0 1.0 0.0 1.0 213.0 36.0 0.0 83.0 104.0 7.0 111.0 395.0 36.0 506.0

3.0 2.0 3.0 0.0 119.0 1.0 0.0 78.0 132.0 0.0 0.0 0.0 115.0 14.0 1.0 50.0 102.0 5.0 107.0 359.0 15.0 466.0

4.0 0.0 10.0 0.0 168.0 3.0 0.0 185.0 61.0 0.0 0.0 0.0 121.0 15.0 0.0 63.0 127.0 8.0 135.0 459.0 15.0 594.0

5.0 2.0 13.0 0.0 125.0 3.0 0.0 234.0 66.0 0.0 0.0 0.0 160.0 14.0 0.0 42.0 116.0 4.0 120.0 472.0 14.0 592.0

3.0 4.0 6.0 0.0 80.0 0.0 0.0 109.0 129.0 2.0 0.0 0.0 145.0 33.0 5.0 86.0 110.0 4.0 114.0 342.0 38.0 456.0

0.7 0.0 0.0 0.7 13.9 0.7 0.4 13.9 29.3 0.4 0.0 0.4

0.2 0.0 0.4 0.6 12.3 0.6 0.0 32.6 27.2 2.9 0.2 0.0

0.6 0.0 1.3 0.9 16.4 0.2 0.0 36.6 19.6 0.6 0.0 0.0

0.7 0.0 1.0 0.2 13.5 0.5 0.0 30.9 24.0 0.5 0.0 0.2

0.2 0.8 1.0 0.2 32.0 0.0 0.0 21.5 19.8 0.2 0.0 0.2

0.6 0.4 0.6 0.0 25.5 0.2 0.0 16.7 28.3 0.0 0.0 0.0

0.7 0.0 1.7 0.0 28.3 0.5 0.0 31.1 10.3 0.0 0.0 0.0

0.8 0.3 2.2 0.0 21.1 0.5 0.0 39.5 11.1 0.0 0.0 0.0

0.7 0.9 1.3 0.0 17.5 0.0 0.0 23.9 28.3 0.4 0.0 0.0

6.0 0.0 9.0 10.0 190.0 6.0 1.0 402.0 327.0 19.0 1.0 1.0 386.0 88.0 2.0 139.0 325.0 20.0 345.0 984.0 90.0 1329.0

7.0 6.0 12.0 2.0 338.0 3.0 0.0 317.0 333.0 3.0 0.0 2.0 452.0 84.0 5.0 186.0 305.0 22.0 327.0 1066.0 89.0 1393.0

12.0 6.0 29.0 0.0 373.0 6.0 0.0 528.0 256.0 2.0 0.0 0.0 426.0 62.0 5.0 191.0 356.0 13.0 369.0 1273.0 67.0 1642.0

0.5% 0.0% 0.7% 0.8% 14.3% 0.5% 0.1% 30.2% 24.6% 1.4% 0.1% 0.1%

0.5% 0.4% 0.9% 0.1% 24.3% 0.2% 0.0% 22.8% 23.9% 0.2% 0.0% 0.1%

0.7% 0.4% 1.8% 0.0% 22.7% 0.4% 0.0% 32.2% 15.6% 0.1% 0.0% 0.0%

Acknowledgments

This project absolutely could not have been accomplished without the very enthusiastic and knowledgeable 

volunteer surveyors who spent 100s of hours walking the slopes of the White Mountains: Carrie Barta, Larry 

Fleming, Andrea Hunter, Duff McEnteer, Jim Nichols, Steve Reidsma, Bob Sattler, and Steve Springer. Lauren 

Attanas and Chris Tannehill also volunteered, but could not participate on any trips because of wildland fires in 

2004 and 2005. Besides myself, paid BLM employees who participated in the surveys include Pat Cotter, Tim 

DuPont, and Steve Lanford. Funding for the project came from the cultural program of the BLM Fairbanks 

District Office, and landscape-level planning funding from the BLM Washington Office; thanks to Richard 

Brook for allocating those latter funds. Cindy Hamfler, BLM-FDO GIS Specialist, produced the landscape 

maps in this report (Figures 1-12). Vanessa Rathbun, BLM-AKSO Visual Information Specialist, laid out 

this report. The BLM Alaska Fire Service provided contracted helicopters at a much-reduced rate, which 

were used to transport the survey crews into the field; the continued support of the AFS for BLM resource 

management work is greatly appreciated.