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Ya Ha Tinda Carnivore Diet Analysis Study
Summer Progress Report
Kara MacAulay and Dr. Evelyn Merrill, University of Alberta
Submitted to: The Wild Sheep Foundation of Alberta
1 October 2016
SUMMARY
The following report is a project update that includes field work completed the summer of 2016 as
part of Kara MacAulay’s MSc. Project at the University of Alberta. Scat analyses in the laboratory
will begin in the fall of 2016 and will be completed in the fall of 2017.
BACKGROUND
Predation risk has previously been modeled using surrogates for risk such as distribution of predators
or encounters between predator and prey (Kristan and Boarman, 2003; Hebblewhite et al. 2005). The
goal of this project to provide a spatial model of mortality risk for ungulate prey by measuring what is
found in the scats of carnivores. Scats reflect actual mortality rather than potential mortality as
measured by other techniques. By analyzing the diets wolves, coyotes, cougars, lynx, grizzly bears and
black bears, we will be able to compare the diets of large carnivores as an indication of which
carnivores may be bighorn sheep predators, and map the relative the predation risk for sheep across
our study area.
Photo credit: K. MacAulay
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OBJECTIVES
The overall objective is to determine whether spatial differences in predator diets reflect predation
risk for bighorn sheep and other ungulates. Using scats from six large carnivores, specifically we
will:
(1) determine what proportion ungulates species, including bighorn sheep, comprise of the
scats of wolves, coyotes, cougars, lynx, grizzly bears and black bears
(2) spatially model the mortality risk to bighorn sheep and other ungulates based on scat
contents across the Ya Ha Tinda region and assess model predictions to known ungulate kill
sites.
METHODOLOGY
Using scat detection dogs, cougar, lynx, grizzly bear, black bear, coyote and wolf scats were
collected over a 1200-km2 study area in Ya Ha Tinda and surrounding areas from 2014 and 2015. We
conducted a final field season in the summer of 2016 from 25-July to 29-August. We divided the
study area into 3 blocks to spatially represent elk distributions patterns in summer (west, central and
east; Figure 1), and to focus our efforts on collecting 100 scats per species spatially representing the
study area. We aimed to collect more felid scats, specifically cougar, as they comprised only 8% of
our data set. Furthermore, they are considered a major predator to bighorn sheep in Alberta, and
preliminary results from cause-specific mortality studies suggest cougars prey upon elk and other
ungulates (Alberta Environment and Parks, 2015). We collaborated with local outfitters and trappers
to determine areas of high cougar use and focused our surveying efforts in those locations.
Furthermore, we sampled off-trail in rugged habitat which is indicative of cougar habitat (Knopff et
al. 2009; Johnson et al. 2013) We surveyed 235-km this past summer to a total of 1292-km sampled
from 2014-2016.
Figure 1. Carnivore scat project study area and transects surveyed from 2014-2016.
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When a scat was located, dog handlers recorded the suspected
species based on physical characteristics such as scat diameter
measurement ranges and physical descriptions of Elbroch (2003),
Weaver and Fritts (1979) and Rezendes (1992). Scats were
ranked visually to estimate time of defecation. Ranks included
‘fresh’ ‘semi-old’, ‘old’, and ‘very-old’ based on colour, moisture
level, presence of mold, and weathering of fecal material. ‘Fresh’
scats had visible mucous lining where ‘very-old’ scats were those
where most of the fecal material was degraded (adapted from
Wasser et al. 2004).
To verify field identification of scats, we swabbed a subset of the
scats for DNA using non-finished toothpicks following protocols
recommended by Wildlife Genetics International. The toothpicks
were used to scrape the outer mucous lining off fresh scats and
dried mucous off semi-old and old scats while avoiding fecal material. The toothpicks were placed in
coin envelopes and stored at room temperature with silica desiccant packages to aid in mucous
drying to preserve the DNA structure. Scats were frozen at -20°C.
RESULTS
We collected 288 scats in Summer 2016, which brings the total of scats collected to 729 over 3
summer seasons (Table 1). The carnivore family group with the highest number of scats collected
was canids (43%), followed by ursids (41%), and the fewest scats collected were from felids (16%).
Table 1. Total number of carnivore scats collected from
2014-2016 from the Ya Ha Tinda region.
a2016 scats have not yet been verified by DNA analysis.
We identified all bear scat as ‘Unknown Bear’ in 2016 because DNA results from 2014 and 2015
indicated handlers were unable to discriminate between grizzly bear and black bear scat in the field
(52% accuracy). We swabbed all bear scat except very old scats since field identification is very
difficult, if not impossible. Coyote scat identification in the field from 2014-2015 was correct only
2014-2015 2016a Total
Grizzly 75 - 75
Black 30 - 30
Unk. Bear 62 131 193
Wolf 129 42 171
Coyote 102 44 146
Cougar 5 27 32
Lynx 35 44 79
Unk. Felid 2 - 2
Unk. Canid 1 - 1
TOTALS 729 Figure 3. A cougar latrine located by a scat detection dog
in Banff National Park. Cougar scats were often found at
the base of a coniferous tree buried under duff or litter.
Photo credit: E. Spilker
Figure 2. A cougar scat with indigestible
material (hair and bones) useful for prey
identification. Photo credit: E. Spilker
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50% of the time, where misidentifying fox as coyote was the most common error. For lynx, 64% of
the scats tested were correctly identified. Only one cougar scat from 2014-2015 was misidentified,
and wolf identification was 88% accurate. We expect DNA analyses from 2016 to be complete in
Spring 2017.
ON-GOING ANALYSES
Revise scat species identification as per DNA
analyses results
Determine the contents of scats using a comparison
of two methods: (1) Macroscopic hair analysis for
detailed analysis of scat contents on a subset of
scats randomly selected to represent a spatial
gradient, and (2) fecal DNA analysis of all scats to
detect the presence absence of a carnivore in a scat.
Using the two methods, determine how many hairs
must be selected from a scat sample in the detailed
analysis to identify accurately all prey species
present (validated through fecal DNA analysis)
Determine what variables (landscape, predator distribution and/or prey distribution) best predict
the amount and presence/absence of a particular prey species in scats of the six carnivores across
the study areas.
Use known adult elk kill sites (2002-2016) and calf elk (2013-2016) to validate predictions of
mortality risk.
Figure 4. Cougar and wolf scat locations from summer 2014-2016 from Ya Ha Tinda and surrounding areas found using scat
detection dogs
Figure 5. Eric Spilker and Rounder taking a break from
surveying for carnivore scat in Banff National Park. Photo
credit: K.MacAulay
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Funding provided by the Wild Sheep Foundation of Alberta will help tremendously during the scat
analysis phase of the project. It will contribute to a technician’s salary who will be responsible for
macroscopic hair analysis, and for contracting the services for fecal DNA analysis. We thank you for
your past and continued support of our research.
ACKNOWLEDGMENTS
We would like to thank the project collaborators and funding partners: Colleges and Institutes
Canada, NSERC, Parks Canada, Safari Club International- Northern Alberta Chapter, University of
Alberta and the Wild Sheep Foundation of Alberta. We would also like to thank Rick and Jean Smith
and other Parks Canada staff for their continued support of our research and for logistical help with
use of the ranch facilities and backcountry cabins. Finally, we would especially like to thank Eric
Spilker his scat detection dog, Rounder. Your knowledge of the study area and willingness to always
keep on surveying allowed us to be very successful during a short field season. Without all of your
support, this project would not be possible!
LITERATURE CITED
Alberta Environment and Parks. 2015. Management plan for bighorn sheep (Draft). Wildlife
Management Plan Series. Wildlife Management Branch. Edmonton, Alberta, Canada
Elbroch, M. 2003. Mammal tracks & sign: a guide to North American species. Stackpole books.
Hebblewhite, M., Merrill, E.H. and McDonald, T.L. 2005. Spatial decomposition of predation
risk using resource selection functions: an example in a wolf-elk predator-prey system.
Oikos 111: 101–111.
Knopff, K.H., Knopff, A.A., Warren, M.B., Boyce, M.S. 2009. Evaluating Global Positioning
System Telemetry Techniques for Estimating Cougar Predation Parameters. J Wildl Manage
73:586–597.
Kristan, W.B.I. and Boarman, W.I. 2003. Spatial pattern of risk of common raven predation on desert
tortoises. Ecology 84:2432–2443
Rezendes, P. 1992. Tracking and the Art of Seeing. Camden House Publishing, Inc. Charlotte,
Vermont.
Wasser, S.K., B. Davenport, E.R. Ramage, K.E. Hunt, M. Parker, C. Clarke, and G. Stenhouse. 2004.
Scat detection dogs in wildlife research and management: Application to grizzly and black
bears in the Yellowhead Ecosystem, Alberta, Canada. Canadian Journal of Zoology 82(3):
475-492.
Weaver, J.L., and S.H. Fritt. 1979. Comparison of coyote and wolf scat diameters. Journal of
Wildlife Management 43(3): 786-788
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