C
OLORADO WILDLIFE SCIENCE
Ecological Research, Management & Consulting
T E C H NI C AL ME MO R AN D U M
To:

Gary Tennenbaum, Director, Pitkin County Open Space & Trails
Lindsey Utter, Planning and Outreach Manager, Pitkin County Open Space & Trails

From:

Jonathan Lowsky, Principal Biologist

Date:

December 26, 2018

Re:

Beaver Occupancy Survey

The North Star Nature Preserve (North Star) is excellent beaver (Castor canadensis) habitat. Beavers
typically inhabit streams with a gentle gradient (< 15%) and in wide valleys (at least wider than the
stream channel) (Bierly 1972). In Colorado, beavers’ preferred forage is woody members of the plant
family Salicaceae (i.e., genus Populus – aspens, cottonwoods and genus Salix – willows) (Pastor and
Naiman 1992). The presence of beavers enhances the heterogeneous complex of wet meadows and
riparian shrublands and increases species richness on the landscape. For example, Wright et al. (2002)
noted that beaver-modified areas may contribute as much as 25% of the species richness of
herbaceous species. Naiman et al. (1988) note that beaver-influenced streams are very different from
those not impacted by beaver activity by having numerous zones of open water and vegetation,
large accumulations of detritus and nutrients, more wetland areas, having more anaerobic
biogeochemical cycles, and in general are more resistance to disturbance. Neff (1957; in Knight 1994)
estimated that a Colorado valley with an active beaver colony had eighteen times more water storage
in the spring and an ability to support higher streamflow in late summer than a drainage where
beaver were removed. It is apparent that active beaver colonies are very important for ecosystem
development in riparian systems such as those at North Star where beaver activity has resulted in the
flooding of former upland areas and creation of new side channels to the river. These areas have
been colonized by herbaceous hydrophytic vegetation, as well as woody riparian plants such as alders
(Alnus incana ssp. tenuifolia), birch (Betula glandulosa), and willows.
Beavers have a relatively low biotic potential due to small litter size and a long juvenile development
period. Beavers, however, are strong dispersers, and populations can recover quickly from local
reductions when dispersal corridors are maintained. Key conservation elements for beavers on OST
lands are, therefore, protection and enhancement of aquatic and riparian habitats by management
of water resources and riparian vegetation.
Following many years of aggressive beaver control by the former owners and neighbors, the beaver
population at North Star has been steadily increasing over the past decade or so. In 2014, Golder Inc.
(Golder Associates 2014) recommended that, in order to assist with the adaptive management of the
property, surveys should be conducted at North Star to determine the number and location of active
lodges, more accurately locate important forage areas, and identify other areas of beaver activity.

I. 2018 SURVEYS
In 2018, Colorado Wildlife Science, LLC (CWS) initiated a survey effort to locate and document all
0100 Elk Run Drive, Suite 128  Basalt, CO 81621  970.927.4549  jonathan@coloradowildlifescience.com  http://coloradowildlifescience.com

 TECHNICAL MEMORANDUM
North Star Nature Preserve Great Blue Heron Colony Assessment
December 26, 2018
Page 2

active and inactive lodges, foraging areas, and other features important to the long term persistence
of beavers at North Star. The surveys were implemented following protocols developed by the U.S.
Forest Service Region 2 (Beck et al. 2009) and the Johnson Creek (Oregon) Watershed Council
(Johnson Creek Watershed Council 2016). Two CWS biologists surveyed the entire river reach (~2.8
mi) and side channels at North Star (Figure 1), recording all beaver lodges and other signs of activity
such as bank tunnels, chewed trees, mud slides, and scent mounds. Each substantial sign of beaver
activity encountered was documented via data sheets and GPS (Most were photographed as well). If
a lodge was found, it was further investigated to determine whether it was active.

II. RESULTS
The 2018 survey effort located 2 active freestanding surface lodges, 2 active bank lodges, 1 inactive
freestanding lodge, and substantial beaver activity throughout North Star’s river reach (Table 1;
Figure 1). This equates to a density of approximately 1 lodge per 0.7 river miles. In addition, we
identified 15 somewhat discrete areas important to beaver ecology at North Star (Figure 1). Most of
Table 1. American beaver activity at North Star
Latitude

Longitude

Bank

Slide

Tunnels

Chew

Canal

Scent Lodge

Comments

39.176035

-106.79709239

East

Y

N

Y

N

N

N

Many recent chews

39.17570

-106.79707

East

Y

N

Y

N

Y

Y

Active slide

39.17486

-106.79741

East

N

N

Y

N

N

N

Major foraging area

39.173359

-106.79514166

East

Y

N

Y

N

N

N

Slide & many chews

39.17228

-106.79301

East

Y

Y

Y

Y

Y

Y

Large surface lodge N of beach, S of obs deck

39.17038

-106.79266

East

Y

N

Y

N

Y

N

Large active foraging area

39.17011

-106.79181

East

Y

N

Y

N

Y

N

Major foraging area with 3 slides, scent mounds

39.16807

-106.79071

East

Y

N

Y

N

Y

N

Foraging area – multiple slides, many chews

39.16689

-106.78972

East

Y

N

Y

N

Y

N

Foraging area

39.16555

-106.78994

East

Y

N

Y

N

Y

N

Important forage area starts here…

39.16509

-106.79085

East

Y

N

Y

Y

Y

N

…and goes to here

39.16556

-106.79172

East

Y

N

Y

N

N

N

Foraging

39.16580

-106.79214

East

Y

N

Y

N

Y

N

Foraging

39.16543

-106.79383

East

Y

N

Y

N

Y

N

Multiple felled trees

39.16366

-106.79233

East

Y

Y

Y

N

Y

Y

Large surface lodge near S border; newer

39.165494

-106.792992

West

Y

N

Y

N

Y

N

Slide with scent mound & recent chews

39.164909

-106.793126

West

Y

N

Y

N

N

N

Slides & mounds; sand dragged into water

39.165131

-106.794599

West

Y

N

Y

N

Y

N

3 food caches

39.164080

-106.79469

West

Y

N

N

Y

N

N

Old, inactive lodge

39.163710

-106.794032

West

N

N

Y

Y

N

N

Large slide between ponds

39.163665

-106.79314062

West

N

N

N

N

Y

N

Modest amount of fresh chew

39.163641

-106.79349369

West

Y

N

N

N

N

N

Large scent mound

39.171560

-106.79280

West

N

N

Y

Y

N

N

Active previous season; some fresh

39.170258

-106.79305938

West

N

N

Y

Y

N

N

Active canal

 TECHNICAL MEMORANDUM
North Star Nature Preserve Great Blue Heron Colony Assessment
December 26, 2018
Page 3

Table 1. American beaver activity at North Star
Latitude

Longitude

Bank

Slide

Tunnels

Chew

Canal

Scent Lodge

Comments

39.170050

-106.791880

West

N

N

Y

Y

Y

N

Heavy activity; willow piles

39.169541

-106.79170391

West

N

Y

Y

Y

N

N

Well used canal

39.167321

-106.79053376

West

N

N

Y

N

N

N

Old dam site washed out

39.166020

-106.792520

West

Y

N

Y

N

N

N

Heavy chew activity on large cottonwoods

these areas are active forage areas marked by canals, chews, and scent piles and 3 are activity areas
associated with the active and inactive lodges. Beavers at North Star clearly preferred willow species
(Salix spp.) with some narrowleaf cottonwood (Populus angustifolia) selected as well. The number of
cut stems was a small percentage of available of willows and cottonwoods within the forage areas.

III. DISCUSSION & MANAGEMENT IMPLICATIONS
Our survey found that the increase in beavers, beaver influenced areas, and beaver dens or lodges
have paralleled the improved health of the riparian ecological system at North Star. Although it is
difficult to determine how many beavers occupy the river reach at North Star, it is likely that each of
the 2 freestanding lodges are occupied by a single beaver family or colony. Beaver colonies usually
consist of an adult pair along with the young of the current and previous years (Olson and Hubert
1994, Longcore 2007). Some studies have estimated that their activities can influence up to 40% of
the total length of 2nd to 5th order streams1 (Naiman et al. 1988, Olson and Hubert 1994).
Plants: The current density of beavers appears to be sustainable and beavers are likely improving
ecological conditions at North Star. Beaver cutting stimulates vigorous sprouting in willow and beaver
and willow can persist indefinitely in a stable equilibrium. Empirical evidence from the headwaters of
the Colorado River in Rocky Mountain National Park (RMNP) showed willow populations can be
entirely dependent on the dams, canals, and ponds built by beaver, which can place water and
sediment on high terraces beyond the reach of other fluvial processes (Westbrook et al. 2006,
Westbrook et al. 2011). Response to beaver foraging depends on plant life history traits. For example,
mountain willow (S. monticola) in RMNP recovered 148.4% of their pre-cut stem number during the
first growing season after all stems were removed to simulate beaver herbivory (Baker et al. 2005).
In addition, willows respond to beaver cutting with a burst of growth that increases stem production
both in terms of numbers of stems per plant and rate of elongation (Kindschy 1985, Kindschy 1989).
Under natural conditions beaver and willow are capable of coexisting on a stream reach indefinitely
because beaver shift centers of foraging which allows willows to recover in a continuing cycle (Hall
1960, Baker 1995, Smith 2007).
Wildlife: Beavers improve many aspects of riparian habitats for wildlife at North Star. Ponds, canals,
and tunnels created by beavers improve water quality, increase riparian area and store water during
dry periods (Olson and Hubert 1994, Baker and Hill 2003). A number of studies have documented
higher bird abundance and diversity associated with beaver activity in comparison with sites without
beavers (Medin and Clary 1990, Grover and Baldassarre 1995, Chandler et al. 2009, Aznar and
1

The Roaring Fork River at North Star is a 5th order stream.

 TECHNICAL MEMORANDUM
North Star Nature Preserve Great Blue Heron Colony Assessment
December 26, 2018
Page 4

Desrochers 2015). In one case, bird densities in active beaver habitats were shown to be three times
that of adjacent riparian habitats (Collins 1993). Forage production is improved around beaver
influenced streams, which increases grazing capabilities for wild and domestic ungulates (Schulte and
Müller-Schwarze 1999, Cooke and Zack 2008). Allowing for and encouraging beaver recolonization in
appropriate areas is widely viewed as a cost-effective wetland and riparian habitat restoration
strategy, especially when compared to the cost and challenge of other human-engineered restoration
alternatives (Burchsted et al. 2010).
Conservation Issues: Historically, the greatest threats to beavers in the Roaring Fork Valley were
overharvesting by the unregulated fur trade from the early 1800’s to the early 1900’s, coupled with
extensive degradation of riparian areas by livestock overgrazing and other human land uses during
the late 1800’s to early 1900’s (Boyle and Owens 2007). The most serious remaining threat to beavers
region-wide is loss and degradation of habitat to human land uses including water manipulations,
livestock grazing in riparian areas, and urban and agricultural development in riparian areas. Excessive
browsing of woody riparian vegetation by wild ungulates, particularly elk and moose, can also reduce
the quality and abundance of beaver food (Kay 1994). Trampling and browsing by large herbivores
can suppress aspen reproduction along streams and reduce beaver food availability (Rutherford 1964
in Boyle and Owens 2007) .
Management Recommendations:
1. Protect cottonwood seedlings and saplings from browsing ungulates.
2. Restore the flood regime on North Star to support seed-based reproduction of
cottonwoods.
3. Restore or allow the continued re-establishment of the cottonwood-willow riparian
community along the river where it is absent.
4. Avoid disturbance of side channels where beavers are active.
5. Establish 50 foot terrestrial buffer zones and river-based quiet zones around lodges, dens,
and activity (e.g., foraging) areas. Exclude recreationists from those areas.

IV. LITERATURE CITED
Aznar, J.-C., and A. Desrochers. 2015. Building for the future: Abandoned beaver ponds promote bird diversity.
Écoscience 15:250-257.
Baker, B. 1995. Restoring healthy riparian ecosystems on western rangelands: beaver as a keystone species.
Bulletin of the Ecological Society of America 2.
Baker, B. W., H. C. Ducharme, D. C. S. Mitchell, T. R. Stanley, and H. R. Peinetti. 2005. Interaction of beaver and elk
reduces standing crop of willow. Ecological Applications 15:110–118.
Baker, B. W., and E. P. Hill. 2003. Beaver. Pages 288-310 in G. A. Feldhamer, B. C. Thompson, and J. A. Chapman,
editors. Wild mammals of North America: Biology, management, and conservation. Johns Hopkins University
Press, Baltimore, MD.

 TECHNICAL MEMORANDUM
North Star Nature Preserve Great Blue Heron Colony Assessment
December 26, 2018
Page 5

Beck, J., D. Dauwalter, K. G Gerow, and G. Hayward. 2009. Design to monitor trend in abundance and presence of
American beaver (Castor canadensis) at the national forest scale.
Bierly, K. F. 1972. Meadow and fen vegetation in Big Meadows, Rocky Mountain National Park. Colorado State
University, Fort Collins, CO.
Boyle, S., and S. Owens. 2007. North American Beaver (Castor canadensis): a technical conservation assessment.
[Online]. . USDA Forest Service, Rocky Mountain Region. Available:
http://www.fs.fed.us/r2/projects/scp/assessments/northamericanbeaver.pdf.
Burchsted, D., M. Daniels, R. Thorson, and J. Vokoun. 2010. The River Discontinuum: Applying Beaver Modifications
to Baseline Conditions for Restoration of Forested Headwaters. Center for Integrative Geosciences. Paper 1.
http://digitalcommons.uconn.edu/geosci/1.
Chandler, R. B., D. I. King, and S. DeStefano. 2009. Scrub-Shrub Bird Habitat Associations at Multiple Spatial Scales
in Beaver Meadows in Massachusetts. The Auk 126:186-197.
Collins, T. 1993. The Role of Beaver in Riparian Habitat Management. Wyoming Game and Fish Department,
Cheyenne, Wyoming.
Cooke, H., and S. Zack. 2008. Influence of beaver dam density on riparian areas and riparian birds in shrubsteppe of
Wyoming. Western North American Naturalist 6.
Golder Associates. 2014. Ecological Communities & Fluvial Geomorphology Baseline Report: North Star Nature
Preserve. R. Mandel & J. Lowsky, lead authors. Unpublished technical report submitted to Pitkin County Open
Space & Trails. Lakewood, CO. 215 pp.
Grover, A. M., and G. A. Baldassarre. 1995. Bird species richness within beaver ponds in south-‐central New York.
Wetlands 15:108-‐118.
Hall, J. G. 1960. Willow and aspen in the ecology of beaver on Sagehen Creek, California. Ecology 41:484-‐494.
Johnson Creek Watershed Council. 2016. Beaver Survey Methods. Available at
http://www.jcwc.org/beavers/#methods. Portland, OR.
Kay, C. E. 1994. The impact of native ungulates and beaver on riparian communities in the Intermountain West.
Natural Resources and Environmental Issues 1:23-44.
Kindschy, R. R. 1985. Response of red willow to beaver use in southeastern Oregon. Journal of Wildlife
Management 49:26-‐28.
Kindschy, R. R. 1989. Regrowth of willow following simulated beaver cutting. Wildlife Society Bulletin 17:290-‐
294.
Knight, D. H. 1994. Mountains and Plains: The Ecology of Wyoming Landscapes, New Haven, CT.
Longcore, T. 2007. Management by Assertion: Beavers and Songbirds at Lake Skinner (Riverside County, California).
Environmental Management 39:460-471.

 TECHNICAL MEMORANDUM
North Star Nature Preserve Great Blue Heron Colony Assessment
December 26, 2018
Page 6

Medin, D. E., and W. P. Clary. 1990. Bird populations in and adjacent to a beaver pond ecosystem in Idaho. Res.
Pap. INT-432. U.S. Department of Agriculture, Forest Service, Intermountain Research Station, Ogden, UT.
Naiman, R. R., C. A. Johnston, and J. C. Kelley. 1988. Alteration of North American streams by beaver. BioScience
38:753-762.
Neff, D. J. 1957. Ecological effects of beaver habitat abandonment in the Colorado Rockies. Journal of Wildlife
Management 21:80-84.
Olson, R., and W. A. Hubert. 1994. Beaver: Water resources and riparian habitat manager. University of Wyoming
Cooperative Extension.
Pastor, J., and R. J. Naiman. 1992. Selective foraging and ecosystem processes in boreal forests. American
Naturalist 139:690-705.
Rutherford, W. H. 1964. The beaver in Colorado: Its biology, ecology, management, and economics. Colorado
Game, Fish, and Parks Department, Fort Collins, CO.
Schulte, B. A., and D. Müller-Schwarze. 1999. Understanding North American beaver behavior as an aid to
management. Pages 109-128 in P. E. Busher and R. Dzieciolowski, editors. Beaver protection, management,
and utilization in Europe and North America. Kluwer Academic and Plenum Publishers, New York, NY.
Smith, J. D. 2007. Beaver, willow shrubs and floods. Pages 603-‐672 in E. A. Johnson and K. Miyanishi, editors.
Plant Disturbance Ecology: The Process and the Response. Elsevier Academic Press.
Westbrook, C. J., D. J. Cooper, and B. W. Baker. 2006. Beaver dams and overbank floods influence groundwatersurface water interactions of a Rocky Mountain riparian area. Water resources research 42:1-12.
Westbrook, C. J., D. J. Cooper, and B. W. Baker. 2011. Beaver assisted river valley formation. River Research and
Applications 27:247-256.
Wright, J. P., C. G. Jones, and A. S. Flecker. 2002. An ecosystem engineer, the beaver, increases species richness at
the landscape scale. Oecologia 132:96-101.

 TECHNICAL MEMORANDUM
North Star Nature Preserve Great Blue Heron Colony Assessment
December 26, 2018
Page 7

BACKGROUND & QUALIFICATIONS

Colorado Wildlife Science, LLC (CWS) is a small wildlife and ecological consulting firm based in Basalt,
Colorado, specializing in wildlife research, management, and monitoring, ecological assessments,
wetland & riparian delineations, conservation easement baseline inventories, ecological planning,
habitat management, and ecological restoration. CWS applies a scientifically sound approach to
biological resource studies and management. Our work combines professional integrity and strong
academic training with extensive experience working for government, private, and non-profit clients.
With an extensive network of professional collaborators that includes plant ecologists, foresters,
hydrologists, and soil scientists, CWS leverages the collective knowledge of experienced professionals
working toward practical, effective and cost saving solutions.
CWS provides expert services to a diverse array of clients. Since we are a small company, personal
attention is ensured. We combine full in-house GIS (ArcGIS) with real-time, sub-meter GPS to provide
state-of-the-art spatial data, analyses, maps, and presentations. We have prepared Biological
Assessments and Biological Evaluations, and contributed to EAs and EISs. CWS has worked with large
private firms such as Jacobs; Carter & Burgess; Mead & Hunt; Parsons; Amec Foster Wheeler; SE
Group; and SAIC as well as city, county, state, and federal agencies such as City of Aspen, City of
Glenwood Springs, Pitkin County, Town of Basalt, Colorado Department of Transportation, and
Roaring Fork Transportation Agency. CWS has prepared over 70 conservation easement baseline and
Present condition reports for 8 different conservation organizations in 5 western Colorado counties.
Owner and Wildlife Biologist Jonathan Lowsky, M.S. Wildlife Biology, Colorado State University, has
a broad range of knowledge. With more than 26 years of professional experience with federal (US
Forest Service), state (Colorado Division of Wildlife), and county agencies as well as two major
universities (Colorado State University and University of Washington), Jonathan’s career has focused
on a diverse array of wildlife from bighorn sheep, elk, and songbirds to northern goshawks, flying
squirrels, small mammals, and spotted bats. Mr. Lowsky’s experience includes biological assessments
and evaluations for NEPA compliance, conservation planning, GIS mapping and modeling, wildlife
research, and ecological monitoring design and implementation, as well as wetland and riparian
delineations, evaluations, and restoration. He has authored management plans and conservation
easement baseline inventory reports and published scientific papers. An expert birder, experienced
tracker, certified wetlands delineator, trained fluvial geomorphologist, and passionate observer of
wildlife, Jonathan has spent countless hours studying and appreciating Colorado’s diverse ecological
communities. A detailed description of Mr. Lowsky’s professional experience and references are
available. For additional information, please visit our website at www.coloradowildlifescience.com.

 TECHNICAL MEMORANDUM
North Star Nature Preserve Great Blue Heron Colony Assessment
December 26, 2018
Page 8

V. FIGURES

 106°47'50"W

106°47'40"W

106°47'30"W

106°47'20"W

39°9'52"N

39°9'52"N

39°10'0"N

39°10'0"N

39°10'8"N

39°10'8"N

39°10'16"N

39°10'16"N

39°10'24"N

39°10'24"N

39°10'32"N

39°10'32"N

106°48'0"W

106°48'0"W

106°47'50"W

106°47'40"W

o

106°47'30"W

106°47'20"W

0

Legend:

50 100

200

300

400

500
Feet

1 inch = 350 fee t

Pi
Pitk
tkiinn Cou
Counnty
ty Op
Open
en Sp
Space
ace &
& Trai
Trails
ls
Am
Ameeric
rican
an Beave
Beaverr Su
Surve
rveyy
Pitkin County, CO

Area of Detail

Figure 1. Results

Important Beaver
Activity Area

Property Boundary

I
H

Inactive Lodge

H
I

Active Lodge or Den

!

Documented
Beaver Activity

Coordinate System:
NAD 1983 StatePlane Colorado Central
Datum: North Am erican 1983

Base Layer Source:
Pitkin County GIS
Digital Orthophotos
2014

Colorado Wildlife Science LLC
Ecological Research, Management & Consulting

0100 Elk Run Dr, Ste 128, Basalt, CO 81621 970.927.4549
jonathan@coloradowildlifescience.com
http://coloradowildlifescience.com

 106°47'40"W

106°47'30"W

106°47'20"W

!7
(

39°10'16"N

39°10'16"N

40
!
(

32
!
(

33
(
!

39°10'8"N

39°10'8"N

34
!
(

36
(
!

39°10'0"N

39°10'0"N

!8
(

39
(
!

(6
!
25
!
(

10
!
(
11
!
(

(4
!1 !
(

27
!
(

12
!
(
39°9'52"N

39°9'52"N

22
(
!

29
(
!

31
(
!
35
(
!

14
(
!

106°47'40"W

106°47'30"W

o

106°47'20"W

0

Legend:

50

100

200

300

400

500
Feet

1 inch = 243 fee t

Pi
Pitk
tkiinn Cou
Counnty
ty Op
Open
en Sp
Space
ace &
& Trai
Trails
ls
Am
Ameeric
rican
an Beave
Beaverr Su
Surve
rveyy
Pitkin County, CO

Area of Detail

Figure 2. Photopoints

Property Boundary

14
(
!

Important Beaver
Activity Area

Photopoint
Location & Number

Coordinate System:
NAD 1983 StatePlane Colorado Central
Datum: North Am erican 1983

Base Layer Source:
Pitkin County GIS
Digital Orthophotos
2014

Colorado Wildlife Science LLC
Ecological Research, Management & Consulting

0100 Elk Run Dr, Ste 128, Basalt, CO 81621 970.927.4549
jonathan@coloradowildlifescience.com
http://coloradowildlifescience.com

 TECHNICAL MEMORANDUM
North Star Nature Preserve Great Blue Heron Colony Assessment
December 26, 2018
Page 11

VI.PHOTOS

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Felled narrowleaf cottonwood - recent
4/26/2018 11:23:56 AM
P1020448.JPG
N 39° 09' 55"
W 106° 47' 39"
WGS-84
1

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Another recently felled narrowleaf cottonwood
4/26/2018 11:24:08 AM
P1020449.JPG
N 39° 09' 55"
W 106° 47' 39"
WGS-84
1

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Recently felled quaking aspen
4/26/2018 11:24:18 AM
P1020450.JPG
N 39° 09' 55"
W 106° 47' 39"
WGS-84
1

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Chew - willow sp.
4/26/2018 11:36:20 AM
P1020452.JPG
N 39° 09' 55"
W 106° 47' 38"
WGS-84
4

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Active forage near trail
4/26/2018 11:36:37 AM
P1020453.JPG
N 39° 09' 55"
W 106° 47' 38"
WGS-84
4

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Recently felled narrowleaf cottonwood
4/26/2018 11:37:21 AM
P1020454.JPG
N 39° 09' 56"
W 106° 47' 34"
WGS-84
6

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Slide
5/10/2018 12:13:37 PM
IMAG4293.jpg
N 39° 10' 01"
W 106° 47' 23"
WGS-84
8

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Dam on side channel - comprised mostly of willow
5/10/2018 12:13:47 PM
IMAG4294.jpg
N 39° 10' 01"
W 106° 47' 23"
WGS-84
8

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Heavy chew activity
5/10/2018 12:20:10 PM
IMAG4295.jpg
N 39° 09' 56"
W 106° 47' 24"
WGS-84
10

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Fresh cuttings
5/10/2018 12:24:07 PM
IMAG4296.jpg
N 39° 09' 55"
W 106° 47' 25"
WGS-84
11

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Lodge - active bank lodge on west bank from opposite
bank
5/10/2018 12:55:29 PM
IMAG4297.jpg
N 39° 09' 52"
W 106° 47' 41"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Active surface lodge near south boundary
5/10/2018 1:09:26 PM
IMAG4301.jpg
N 39° 09' 49"
W 106° 47' 32"
WGS-84
14

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
North active surface lodge
10/16/2018 10:20:47 AM
P1020458.JPG
N 39° 10' 20"
W 106° 47' 35"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
10/16/2018 10:21:02 AM
P1020459.JPG
N 39° 10' 20"
W 106° 47' 35"
WGS-84
39

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Another tunnel at north lodge
10/16/2018 10:21:24 AM
P1020460.JPG
N 39° 10' 20"
W 106° 47' 35"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Beaver observed in this tunnel
10/16/2018 10:21:49 AM
P1020462.JPG
N 39° 10' 20"
W 106° 47' 35"
WGS-84
39

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Slide and chew activity
N3.JPG
N 39° 09' 54"
W 106° 47' 35"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Slide and chew activity
N2.JPG
N 39° 09' 54"
W 106° 47' 35"
WGS-84
39

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Slide and chew activity
N1.JPG
N 39° 09' 54"
W 106° 47' 35"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Slide, scent mound, chew
M2.JPG
N 39° 09' 56"
W 106° 47' 35"
WGS-84
39

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Slide, scent mound, chew
M1.JPG
N 39° 09' 56"
W 106° 47' 35"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Old, inactive lodge remnants
P2.JPG
N 39° 09' 53"
W 106° 47' 41"
WGS-84
39

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Old, inactive lodge
P1.JPG
N 39° 09' 53"
W 106° 47' 41"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Large slide between ponds
Q2.JPG
N 39° 09' 51"
W 106° 47' 41"
WGS-84
39

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Large slide between ponds
Q1.JPG
N 39° 09' 51"
W 106° 47' 41"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Chew near active slide
R.JPG
N 39° 09' 49"
W 106° 47' 39"
WGS-84
39

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Slide
T.JPG
N 39° 10' 13"
W 106° 47' 35"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Cuttings
U.JPG
N 39° 10' 12"
W 106° 47' 31"
WGS-84
39

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Recent chew on mature willow
V.JPG
N 39° 10' 10"
W 106° 47' 30"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
South active lodge from opposite bank
VV.JPG
N 39° 09' 49"
W 106° 47' 33"
WGS-84
39

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Dam attempt remnants
W3.JPG
N 39° 10' 03"
W 106° 47' 26"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Heavy chew activity
W2.JPG
N 39° 10' 03"
W 106° 47' 26"
WGS-84
39

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Chew & food cache
W1.JPG
N 39° 10' 03"
W 106° 47' 26"
WGS-84
39

2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Heavy chew on large cottonwoods
X.JPG
N 39° 09' 58"
W 106° 47' 33"
WGS-84
39

 2018 American Beaver Survey

Title
Subject
Comment
Date/Time
File Name
Latitude
Longitude
Map Datum
Photopoint

Attributes
North Star Nature Preserve
2018 American Beaver Survey
Chew from previous season with some fresh
S.JPG
N 39° 10' 18"
W 106° 47' 34"
WGS-84
39