Population vital rates of resident and translocated female greater sage-grouse

作者：Gruber Hadden Natasha W^*; Messmer Terry A; Maxfield Brian D; Koons David N; Guttery Michael R

来源：Journal of Wildlife Management, 2016, 80(4): 753-760.

DOI：10.1002/jwmg.1062

• Centrocercus urophasianus
• greater sage-grouse
• isolated landscapes
• translocation
• Utah
• vital rates

Translocations have been recommended to reestablish, augment, and sustain genetic diversity in declining wildlife populations, including greater sage-grouse (Centrocercus urophasianus; sage-grouse). Characteristics of successful sage-grouse translocations include suitable contiguous sagebrush (Artemisia spp.), seasonal habitats surrounded by geomorphic barriers, a residual resident population, and pre-nesting releases. From 2009 to 2010, we studied vital rates of 60 translocated and 15 resident radio-marked female sage-grouse and their broods on Anthro Mountain, in the Ashley National Forest, northeastern Utah, USA to determine whether translocations could augment a declining meta-population that inhabited suitable breeding habitats in a small spatially isolated landscape. Survival rates, and nest and brood success estimates for the resident and translocated sage-grouse we studied were lower than reported range-wide averages. Nest success was similar for resident and translocated birds (survival estimate: 0.468, 95% CI=0.288-0.648) and we calculated weak, yet positive relationships to grass height and grass cover. Daily survival rates for chicks 0-19 days of age for resident females in 2009 (0.904, CI=0.875-0.940) and in 2010 (0.910, CI=0.888-0.945) were higher than for chicks raised by translocated females (0.883, CI=0.850-0.915; 0.892, CI=0.856-0.936, respectively), although differences were small and all 95% confidence intervals had substantial overlap. In 2009 and 2010, daily survival rates for chick 20-50 days of age were slightly higher for chicks reared by resident females (0.980, CI=0.963-0.994; 0.998, CI=0.978-1.000, respectively) than chicks reared by translocated females (0.877, CI=0.623-0.959; 0.988, CI=0.945-0.993, respectively). Chick survival for both groups was weakly correlated with grass cover. Although most translocated birds remained on the study area (82%), the low overall survival rates we report indicate that managers need to consider factors affecting survival of adult females, nests, and chicks when planning future translocations to augment sage-grouse meta-populations that occupy spatially isolated and space-limited habitats.

• 出版日期2016-5