kodiak mtgoat cobb_20111019
TRANSCRIPT
Ghosts of the Hil ls :
Mountain Goats
on Kodiak
McCrea Cobb Kodiak National Wildlife Refuge
Brown Bag Lunch Series
Oct. 20, 2011
Ghosts of the Hills
Presentation Outline
• Natural history and
ecology
• How goats ended up
on Kodiak
• Research and
monitoring work
– 2011 Field Season
• Future research and
monitoring goals
B. Dunker
Mountain Goats
• Member of Caprinae
– “Goat/antelopes”
• Serow spp.
• Goral spp.
• Chamois spp.
– Only living
species in it‟s genus
Natural History
• Distribution
• Western N.A.
• S. to Colorado
• N. to Alaska
• 80-120K goats
• ~58K in Canada
• ~12K in lower 48
• ~30K in Alaska
Alaska Distribution
ADF&G
Life History
• Diet and Habitat
– Graze grasses, sedges,
forbs, lichens, ferns,
and moss.
– May browse shrubs and
conifers during the
winter when other
forage is unavailable.
– Need escape terrain
• Especially important
during kidding season.
Life History • Home Ranges
– Generally small
• 300 ha females
• 1,200 ha males
• Movements
– Daily to acquire food, rest, find a mate, thermoregulate, and avoid predators.
– Seasonal for nutritional and reproductive needs.
• Altitudinal migrations
K. White ADF&G
K. White ADF&G
Annual Life Cycle
• Nannies give birth to 1
kid (usually) in late
May – early June
• Rut in late Oct.– early
Dec.
• Billies solo to
small groups.
• Nannies/kids
nursery groups
Nanny or Billy?
Quiz: Nanny or Billy?
N
B
K
Nanny or Billy?
B
N
Nanny or Billy?
B
B
N
N N
?
Introductions to Kodiak Species Release Date Release Site Current Status
Sitka deer 1924, 1934 Long & Kodiak Is. ~60-80,000 (?)
Roosevelt elk 1929 Afognak Is. ~610 (2010)
Moose 1966, 1967 Kodiak Is. XX
Reindeer 1924 Alitak Bay ~320
Dall sheep 1964, 1965 Kodiak Is. XX
Beaver 1929 Kodiak & Raspberry Is. 30-50,000 (?)
Muskrat 1925 Long Is. Chiniak area
Marten 1952 Afognak Is.
(Paramanof)
2-3,000 (?)
Mink 1952 Kodiak Is. (Karluk) XX
Snowshoe hare 1934 Kodiak & Afognak Is. 100,000 (??)
Red squirrel 1952 Afognak & Kodiak Is. 10-15,000 (?)
Raccoon pre-1936 & 1980 Long & Kodiak Is. XX
Spruce grouse 1957, 1959 Woody Is. XX
Vancouver Canada goose 1986 Shuyak & Kodiak Is. ~1,000 (?)
Goat
Introductions • “Easier rugs or roasts
should be available and in more places”
• 1924, 18 goats introduced to Baranof Is.
• Federal Aid in Wildlife Restoration funding
• Experimented with numerous methods to capture • Dogs
• “feed pail” traps
• Collapsible box trap
• Self-injecting syringe on an arrow
• Drop net from a helicopter
Goats to
Kodiak
• Initial attempts
were unsuccessful.
• Private trappers
– $350-400/goat
– Dangerous work
• 18 goats captured
in 1952 and 1953.
1952-1953
1975-1984
1984-1995
1985-1994
2004-2010
Population Growth
0
500
1000
1500
2000
2500
# G
oats
Cou
nte
d
*Currently ~2,400 – 2,600 goats island-wide
Population Growth
Management Concerns • Mountain goats are
an economically important game species on Kodiak.
– Maintaining high harvests in important
• Rapid population growth is a concern.
– Classic ungulate irruptive growth pattern
– Potential for long-lasting changes to the landscape
Management Goal:
• Maintain a sustainable mountain goat population
that:
1) Meets agency harvest objectives.
2) Does not detrimentally impact native flora and fauna.
Management Questions
1. An estimate of the number of goats, with confidence intervals.
2. An understanding of the effects of hunting and other limiting factors on changes in population size.
3. An understanding of how big the population can get without causing damage to the landscape.
Information Needs
1. An estimate of the number of goats, with confidence intervals.
2. An understanding of the effects of hunting and other limiting factors on changes in population size.
3. An understanding of how big the population can get without causing damage to the landscape.
1. How many goats are not being counted during surveys.
2. Rates and sources of mortality and reproductive rates.
3. Resource selection patterns
1. Diet
2. Feeding Site Selection
3. Habitat Selection
Summer 2011 Pilot Field Study
• Goals:
1. Quantify
mountain
goat diets.
2. Determine
feeding
site
selection.
Where? • 3 study sites
– Hidden Basin/
Terror Lake
– Uyak region
– Hepburn Pen.
• Selected based on
duration of goat
occupancy.
• Visited each study
site twice between
May and Aug.
What did we do?
• Diet
– Collected fresh
pellets
– Sent to WSU
– Results by Feb „12
What did we do?
• Feeding Site Selection
– Transects at feeding
sites and random
locations
– 17 plots along transects
– Surveyed plant species
diversity and
composition
• Will compare data
from feeding sites to
random locations
Preliminary Results
• Surveyed 298 plots
• 5,066 plots!
• 161 unique plant
species / habitats
– Most common plants:
• Long-awned sedge,
patridgefoot, arctic
daisy, black
crowberry
• Distance to rock
outcropping
important, slope less.
Future Research Goals
• Cost-effective estimate of population size that includes confidence interval
– VHF radio collars
• Resource Selection
– GPS collars
• Survival & Reproduction
– Monitor collared goats
The Goat Crew