predator prey dynamics

historic predator-prey models

Lotka-Volterra model, Guase, Huffaker (mites and oranges), Holling, Morris, Errington

wolf-livestock tension zones in AB

where wolves and agriculture interacts

government compensation when wolves kill livestock

ways to study wolves in the field

observations, scat collections, carcasses (inform population structure and reproduction), radio tracking with VHF radios,

more common now are satellite tracking and computer technology

wolf and man competition?

each wolf in NWT kills about 25-35 caribou per year, wolf eradication thus saved about 207 000 caribou

modern calculations say that one elk is worth about $2000 in food

similarly, wolf kill about 22 elk per year which then = $44 000

do wolves surplus kill?

not very common, only if they had so much food at one point

some examples of them partially killing calves to feed on milk curds in the stomach

wolf control in NWT 1950s

6890 wolves were poisoned in ten years to protect food supply for northern communities (probs wouldn’t pass today considering public input)

rough calculations assume approx 3500-6289 tons of human food lost to these 6000 wolves

caribou declines in NWT

bathurst herd declined from 470 000 in 80s → 8200 in 2019

bluenose herd declined from 100 000 in 2010 → 19 000 in 2019

HUGE declines attributed to wold predation, human hunting, climate change, fires, and more

wolves in yellowstone

historically persecuted by govt and ranchers, last killed in 1926

but lack of wolves and other large predators resulted in massive increases of elk, peaking at about 14 000 → ecosystem services and biodiversity threatened

reintroduced in 1995 w wolves from alberta, also contributed to the increase in bison numbers

ecological cascade effects

huge increases in tourism revenue and visitation with the reintroduction (compared to minimal losses in hunting)

diseases in wolves

canine distemper - viral and impacts adults

parvo virus - kills pups, very contagious

rabies - bacterial, contagious via biting, dangerous to humans and warm blooded hosts

mange - ecto-parasite, recovery is possible but contagious

ungulate disease in yellowstone

brucellosis

infection rate varies depending on feeding grounds

only elk transfer to cattle, bison do not