The Efficacy of Translocation as a Tool to Augment Populations of Gambel’s Quail (Callipepla gambelii)

Abstract

Translocation is a valuable management strategy that can be used to augment and reestablish populations or increase the range of a species by establishing new populations. Gambel’s quail (Callipepla gambelii) are an iconic species enjoyed by all and are the only native upland game bird in many desert areas of the American Southwest. Drought may be a driver in the population decline of Gambel’s quail; however, quail in urban environments, such as golf courses, can remain abundant due to 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 the augmentation of populations of Gambel’s quail, we translocated 370 quail to augment 2 sites in the Altar Valley, Arizona: King’s Anvil Ranch (KA) and Santa Margarita Ranch (SM). We fitted 155 female quail with VHF radio-transmitting collars and released them on 2 study areas (KA: n = 77, SM: n = 78). Release site had the most impact on demographic rates. KA quail had higher survival to 200 days post-release (63.4% - 70.9%) than SM quail (19.3% - 33.1%); however, SM quail had higher nesting effort and success (nest effort = 63%, nest success = 50%) than 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 augmentation may have had some short-term benefits in reproductive activity, we are not able to conclude from these data that it led to a measurable increase in 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.