Affiliation:
1. Washington Department of Fish and Wildlife Olympia WA 98501 USA
2. Olympic National Park 600 E. Park Avenue Port Angeles WA 98362 USA
3. Washington Department of Fish and Wildlife Ellensburg WA 98926 USA
4. Stillaguamish Tribe of Indians Arlington WA 98223 USA
5. Muckleshoot Indian Tribe Wildlife Program 39015 172nd Avenue SE Auburn WA 98092 USA
6. University of Alaska Southeast Juneau AK 99801 USA
7. Sauk‐Suiattle Tribe Darrington WA 98241 USA
Abstract
AbstractElucidating patterns of adult survival rates is key to understanding population dynamics of large mammals. We used data from 7 separate studies of mountain goats (Oreamnos americanus) conducted from 2002 through 2022 in western Washington, USA, to quantify survival rates in relation to key biotic and abiotic factors using known fate models implemented in program MARK. We monitored 324 (206 females, 118 males) radio‐marked mountain goats for 178,339 days. A substantial number of mountain goats in our sample (n = 217) had been translocated from the Olympic Peninsula to the Cascade Mountains on Washington's mainland, providing an added opportunity to examine translocation effects. We adopted a sequential modeling approach, first building a set of models to examine fundamental survival patterns by age, sex, season, study area, and translocated status. We used variables retained from the top model in a second set to investigate relationships between annual survival and local weather covariates hypothesized by previous studies to influence mountain goat behavior, habitat selection, and vital rates. Survival among adult females in spring was slightly lower than other sex and age categories, but seasonal patterns were otherwise not evident. There were significant negative relationships between survival and winter snow depth, an index of the previous year's drought, and mean daily temperature during the previous May, and a positive relationship with previous year's precipitation. Weather effects were similar among resident and translocated animals. By the end of the study period, weather effects had evidently contributed to reductions in mountain goat survival to a level low enough that population stability was unlikely. Because the frequency of droughts and warm spring temperatures are expected to increase with climate change, mountain goat populations in Washington will likely be increasingly challenged as the atmosphere warms.
Subject
Nature and Landscape Conservation,Ecology,Ecology, Evolution, Behavior and Systematics,Nature and Landscape Conservation,Ecology,Ecology, Evolution, Behavior and Systematics