Effects of Climate on Scaled Quail Reproduction and Survival
Across the southwestern U.S., long-term declines in populations of scaled quail and contraction of their range-wide distribution have caught the attention of avian ecologists (Cantu et al. 2006). One of the factors hypothesized as a primary cause of this decline is a long-term trend in warmer, drier conditions and reduced monsoonal rainfall across their range. The mechanism believed to be driving this trend is declining nest success due to temperature and humidity levels above a critical threshold for egg and chick survival. While habitat loss cannot be discounted as a possible driver, areas managed specifically for scaled quail in western Texas have seen similar losses in population numbers across the same time frame indicating that these reductions are independent of habitat related factors (Rollins 2000). Coupled with climate models forecasting shifts in the arrival of summer monsoon rains away from the critical reproductive periods of June and July (Cook and Seager 2013), the long-term forecast for scaled quail response to decreased rainfall and higher temperatures is bleak. Scaled quail are considered to be a key indicator species of the health of the habits they occupy across the southwest and are frequently used to assess the success of restoration projects undertaken by federal and state agencies (Coffman 2012). Researchers will use this species to study climate effects (temperature, humidity, and precipitation) preceding, during and following the nesting season with a primary focus on how these climate variables affect nest success. The primary objective will be to measure nest success in different populations across their range and determine if nest success is related to temperature and humidity measurements taken in incubating nests using ibuttons. This project could be expanded in future years if funding becomes available to compare presence/absence of scaled quail on White Sands Missile Range (where habitat condition is driven by only climate variables because grazing has not occurred in over 50 years) using drought indices to determine if measures of precipitation, temperature and humidity can predict scaled quail abundance.