The efficacy of translocation as a tool to augment populations of Gambel's quail

Abstract

AbstractTranslocation is a management strategy that can be used to augment and reestablish populations or increase a species' range by establishing new populations. Gambel's quail (Callipepla gambelii) are the only native upland game birds in many desert areas of the American Southwest. Drought may be a driver in Gambel's quail population declines; however, quail in urban environments may remain abundant because these areas may contain more reliable sources of food, water, and cover. We hypothesized that translocation of urban quail following a wet winter, when resources are plentiful in their native habitat, might allow us to increase the rate at which extant populations are able to recover following drought by capitalizing on the high reproductive capacity of quail. To assess translocation as a management tool for augmentation of populations of Gambel's quail, we translocated 370 quail from 2019 to 2021 to augment 2 sites in the Altar Valley in Arizona, USA: King's Anvil Ranch (KA) and Santa Margarita Ranch (SM). We radiotracked 155 female quail on 2 study areas (KA: n = 77, SM: n = 78) to estimate 200‐day post‐release survival. Release site had the most impact on demographic rates. Quail in KA had higher survival (63.4–70.9%) than quail in SM (19.3–33.1%); however, quail in SM had higher nesting effort and success (nest effort = 63%, nest success = 50%) than quail in KA (nest effort = 33%, nest success: 0%) in the first year. Although this study showed that urban quail can survive and reproduce following translocation, neither site showed both high survival and high reproductive success. Furthermore, although spring call counts indicated augmentation may have had some short‐term benefits due to increased reproductive activity, we are not able to conclude that it increased quail abundance. Given the low annual adult survival rates of Gambel's quail, high spring‐summer survival alone will not be enough to boost wild populations in a measurable way the following year. Therefore, the ability of translocation to augment extant populations may be limited by low and variable reproductive success.