Demographic data provide a basis for understanding the life history and ecology of species, factors which are vital for informing conservation efforts; however, little is known regarding the population ecology of most snake species, including the threatened Eastern Indigo Snake (Drymarchon couperi). We used 11 years (1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)) of capture-mark-recapture (CMR) and 2.5 years (2003)(2004)(2005) of radiotelemetry data from southeastern Georgia, USA, in a CMR modeling framework to estimate apparent survival, capture and transition probabilities, and evaluate factors influencing these parameters. The model-averaged estimate of overall apparent annual survival probability was 0.700 (±0.030 SE) and is comparable to that obtained from known fate analysis (radiotelemetry) at the same site. Body size positively influenced survival, regardless of sex. Capture probability differed seasonally by sex, suggesting lower capture probability for females in fall and males in winter. There was no evidence for effect of precipitation or site-specific differences in survival. Model averaged estimate of annual adult survival estimated using multistate CMR models was 0.738 ± 0.030 and 0.515 ± 0.189 for subadults. We estimated population growth rate (k) and elasticity (proportional sensitivity) of k to vital rates using a stage-structured matrix population model. Population growth rate ranged from 0.96 to 1.03 depending on the value of the probability of transitioning from subadult to adult stage. The k was proportionally most sensitive to changes in adult survival rate, followed by subadult survival. Our results suggest that protecting adult snakes and their habitats would result in the highest likelihood of long-term population stability and growth.

Picoides borealis (Red-cockaded Woodpecker) is an endangered bird endemic to the Pinus (pine) ecosystems of the southeastern US. Mature pine savannahs with a minimal midstory and lush herbaceous groundcover represent high-quality habitat. This study examines the foraging-habitat patterns of Red-cockaded Woodpeckers in East Texas. We present a logistic regression model that best differentiates between foraged and non-foraged habitat. Increases in hardwood-midstory basal area have the greatest negative impact on the probability of Red-cockaded Woodpeckers selecting a habitat patch for foraging. Five additional variables negatively impact foraging probability: shrub height, diameter at breast height (DBH) of pine midstory, canopy closure, density of pine midstory, and density of hardwood midstory. Our model shows a high degree of accuracy as to the probability of habitat-patch selection for Red-cockaded Woodpeckers foraging in East Texas forests composed of different pine species.

The eastern indigo snake (Drymarchon couperi) is the longest snake in North America. Population declines due to extensive loss of habitat led to federal listing as a threatened species in 1978. Knowledge deficiencies regarding the biology of the eastern indigo snake, including population connectivity and gene flow, are impediments to the development of effective conservation and restoration strategies. We describe primers and polymerase chain reaction (PCR) conditions to amplify 22 tetranucleotide and pentanucleotide nuclear microsatellite loci isolated from the eastern indigo snake. We tested primers using 28 shed skins representing 24 individuals from Fort Stewart, Georgia. Primers yielded an average of 4.6 alleles per locus (range 3-7) and an average observed heterozygosity of 0.63 (range 0.46-0.79). These loci should prove useful for individual identification as well as population level analyses of this federally threatened species.

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