Effectiveness of Surrogators As A Propagation Tool for Northern Bobwhites In South-Central Texas
Abstract
Attempts to restore populations of northern bobwhites (Colinus virginianus) using game-farm quail have been documented since the early 1900s. Low restoration success rates are likely to the result of low post-release survival rates (8-15 days) and long distance dispersal from release sites averaging 2.33 km. Claims have been made that Surrogators®, a quail propagation tool, has increased success rates in both these areas. Following steps outlined in the Wildlife Management Technologies 2009 Surrogator System Guide, I tested the effectiveness of surrogators on bobwhite survival, dispersal, and habitat selection. I accomplished this by raising 1,000 bobwhites in two surrogators and conducting two trials per year in 2009 and 2010 on a 990-ha ranch in Wilson County, TX. Twenty bobwhites from each surrogator were fitted with transmitters 12 h before release. I attempted to locate each bobwhite daily for 3 weeks, followed by a reduced effort of three times per week until mortality reached 100%. Transmitter attachment techniques used during 2009 failed; thus no data were recorded on mortality and dispersal. Bart and Robson’s Maximum Likelihood Estimators of daily survival rates calculated for bobwhites released from surrogators A and B during the first trial 2010 were low (0.87 and 0.96, respectively). Daily survival rates of bobwhites calculated for surrogators A and B in the second trial of 2010 were also low (0.83 and 0.87, respectively). Mean distances traveled by bobwhites post-release during the first trial of 2010 were 401 m and 1,416 m for surrogators A and B, respectively. Dispersal statistics were not calculated for the second trial of 2010 because of small sample size (n < 2). There was no difference in habitat use. My results do not support the use of surrogators as an effective means of restoring wild populations of northern bobwhites in southern Texas.
