The origin, connectivity, and individual specialization of island wolves after deer extirpation DOI
Charlotte E. Eriksson, Gretchen H. Roffler, Jennifer M. Allen

et al.

Ecology and Evolution, Journal Year: 2024, Volume and Issue: 14(4)

Published: April 1, 2024

Wolves are assumed to be ungulate obligates, however, a recently described pack on Pleasant Island, Alaska USA, is persisting sea otters and other marine resources without prey, violating this long-held assumption. We address questions about these wolves regarding their origin fate, degree of isolation, risk inbreeding depression, diet specialization by individual sex. applied DNA metabarcoding genotyping amplicon sequencing using 957 scats collected from 2016 2022, reduced representation tissue samples establish detailed understanding Island wolf ecology compare them with adjacent mainland wolves. Dietary overlap was higher among (Pianka's index mean 0.95 ± 0.03) compared (0.70 0.21). The diets island were dominated otter, ranging 40.6% 63.2% weighted percent occurrence (wPOO) (mean 55.5 8.7). In contrast, primarily fed ungulates (42.2 21.3) or voles during population outbreak (31.2 23.2). traced the pair that colonized around 2013 produced several litters. After breeding killed, female offspring an immigrant male became new breeders in 2019. detected 20 individuals which 8 (40%) trapped killed while two died natural causes 6-year study. Except for male, pedigree analysis genotype results showed no additional movement island, indicating limited dispersal but evidence inbreeding. Our findings suggest exhibit more flexible foraging behavior than previously believed, hunting strategies can substantially differ between within packs. Nevertheless, anthropogenic mortality combined connectivity may inhibit continued persistence

Language: Английский

Switching to marine prey leads to unprecedented mercury concentrations in a population of coastal Alaska wolves DOI Creative Commons
Gretchen H. Roffler, Angela Gastaldi,

Camilla Lieske

et al.

The Science of The Total Environment, Journal Year: 2025, Volume and Issue: 980, P. 179542 - 179542

Published: April 30, 2025

Methylmercury (MeHg) bioaccumulates in organisms and biomagnifies food webs, resulting elevated concentrations tissues of apex predators that may negatively impact health. As MeHg is mainly produced by aquatic microbes, feeding webs tend to have higher mercury (Hg) their than those terrestrial webs. In a region coastal Southeast Alaska, wolves switched from marine-based diet specializing on recently recovered sea otters. We hypothesized this prey switch would lead Hg wolf tissues. Therefore, we quantified total (THg) hair (n = 25) THg liver 7), muscle 3), kidney 2), brain 2) two packs - marine foraging island pack (located Pleasant Island), an adjacent mainland the Gustavus Forelands) with predominantly diet. paired information carbon (δ13C) nitrogen (δ15N) stable isotope analyses 65) collected 2000 2023 determine proportional contribution subsidies infer trophic positions packs. For comparison completely diet, Interior Alaska wolves. Liver Island (mean 17.59 ppm; range 0.63-64.30) categorized individuals at 'high risk' 'severe were 7 278 times other wolves, respectively, 11 >2000 reported globally. increased both δ13C δ15N indicating for position species exposes level which health consequences.

Language: Английский

Citations

0

Vegetation influences wolf fine-scale habitat selection and movement rate in a logged coastal rainforest DOI Creative Commons
David P. Gregovich, Gretchen H. Roffler, Christina M. Prokopenko

et al.

Oecologia, Journal Year: 2025, Volume and Issue: 207(3)

Published: Feb. 27, 2025

Vegetation and its modification by humans can shape wildlife habitat selection movement. A better understanding of how wolves select move through natural human modified vegetative cover be used to implement forest management that considers impacts on their prey. We analyzed fine-scale wolf movement in a coastal temperate rainforest (Prince Wales Island, Alaska, USA) relation to: (1) young (≤ 30 years) old (> logged areas, (2) continuous measures (as estimated via LiDAR), (3) distance roads, using integrated step-selection analysis (iSSA). Wolves selected areas with less canopy understory at the population level, although they switched selecting when within stands. The vary fine spatial scale thus appear explain than categorical landcover classes representing age Wolf successional near was mixed across individuals. All individual avoided cover, but varied stands, understory, roads. Similarly, there variability rate response wolves, level moved faster vegetation. Open vegetation including present recently after logging is facilitates movement, this effect may ephemeral as undergoes succession.

Language: Английский

Citations

0

The origin, connectivity, and individual specialization of island wolves after deer extirpation DOI
Charlotte E. Eriksson, Gretchen H. Roffler, Jennifer M. Allen

et al.

Ecology and Evolution, Journal Year: 2024, Volume and Issue: 14(4)

Published: April 1, 2024

Wolves are assumed to be ungulate obligates, however, a recently described pack on Pleasant Island, Alaska USA, is persisting sea otters and other marine resources without prey, violating this long-held assumption. We address questions about these wolves regarding their origin fate, degree of isolation, risk inbreeding depression, diet specialization by individual sex. applied DNA metabarcoding genotyping amplicon sequencing using 957 scats collected from 2016 2022, reduced representation tissue samples establish detailed understanding Island wolf ecology compare them with adjacent mainland wolves. Dietary overlap was higher among (Pianka's index mean 0.95 ± 0.03) compared (0.70 0.21). The diets island were dominated otter, ranging 40.6% 63.2% weighted percent occurrence (wPOO) (mean 55.5 8.7). In contrast, primarily fed ungulates (42.2 21.3) or voles during population outbreak (31.2 23.2). traced the pair that colonized around 2013 produced several litters. After breeding killed, female offspring an immigrant male became new breeders in 2019. detected 20 individuals which 8 (40%) trapped killed while two died natural causes 6-year study. Except for male, pedigree analysis genotype results showed no additional movement island, indicating limited dispersal but evidence inbreeding. Our findings suggest exhibit more flexible foraging behavior than previously believed, hunting strategies can substantially differ between within packs. Nevertheless, anthropogenic mortality combined connectivity may inhibit continued persistence

Language: Английский

Citations

2