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.

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Military lands are a valuable resource in recovery of threatened, endangered, and at-risk species worldwide and have the highest density of threatened and endangered species of all major land management agencies in the United States. Many red-cockaded woodpeckers (Picoides borealis) that reside on federal lands occur on 15 military installations in the southeastern United States. This close association has increased concern over potential conflicts between conservation requirements of endangered species and the military's mission of combat readiness. Our objectives were to 1) determine if military training operations affect behavior, reproductive success, and productivity of red-cockaded woodpeckers; 2) develop a frequency-weighting function to assess woodpecker hearing sensitivity; 3) identify factors that affect woodpecker responses to military training operations; 4) develop distance and dose-response thresholds for quantifying woodpecker responses to noise levels and stimulus distances; 5) characterize military training operations through quantification of sound levels, source identification, distance from active woodpecker nests, frequency spectra, duration, and frequency of occurrence; and 6) document baseline woodpecker nesting behavior. We conducted our study on the Fort Stewart Military Installation located in southeast Georgia, USA.Downy woodpeckers, as surrogates for red-cockaded woodpeckers, had their best hearing sensitivity within the peak range of the power spectrum of both downy and red-cockaded woodpecker vocalizations, which is at a higher frequency than that of a typical passerine. Overall, woodpeckers had a reduced auditory sensitivity relative to human hearing sensitivity and other species of small birds, especially in the frequency range >4 kHz. Woodpeckers were most sensitive in the 1.5-to 4.0-kHz range. Sensitivity appeared to drop off quickly at frequencies <1.0 kHz and >4.0 kHz. Overall, we did not find that the woodpecker-frequency-weighting function we developed provided a better predictor of woodpecker flush response compared with A-weighting. More research is needed to better understand the relationship between frequency-weighting functions and woodpecker response behavior.Potential breeding groups of woodpeckers across the population increased from 158 in 1997 to 181 in 2000, wheras nesting groups increased from 141 in 1998 to 170 in 2000, for overall increases of 14.6% and 20.6%, respectively, over the 3 years of this project. Fledging success rates for individual nests within the overall population remained consistent from 1998 to 2000, averaging 84.4%. Mean clutch sizes for woodpecker groups for 1998 to 2000 ranged from 2.75 to 3.01 eggs/nest, brood size ranged from 2.01 to 2.22 nestlings/nest, whereas the average number of young fledged ranged from 1.57 to 1.76 young/ occupied nest. We observed no difference in reproductive success or productivity between experimental and control-tested red-cockaded woodpecker groups. Overall, experimental test groups produced an average of 2.98...

Blood parasites and nest cavity arthropods associated with the red-cockaded woodpecker (Picoides borealis) were surveyed and the impact of blood-feeding arthropods on woodpecker fitness traits was assessed. Five woodpeckers (8%) were infected with unidentified microfilariae, and 1 woodpecker (2%) was infected with 2 species of haemoproteid (Haemoproteus velans and Haemoproteus borgesi). This is the first record of haemoproteids in this species and the first observation of H. borgesi in North America. We collected representatives of at least 6 families of mites and 12 families of primarily commensal insects from woodpecker cavities. Only a few specimens of blood-feeding insects were recovered. The mite Androlaelaps casalis was the most common hematophagous arthropod (prevalence = 76%, mean density = 51+/-7 mites/cavity). The number of A. casalis mites increased with cavity age but there was no association between the number of mites and the number of woodpecker eggs laid or the number of hatchlings or fledglings. In conclusion, the prevalence of blood parasites in the red-cockaded woodpecker is low, woodpecker cavities are not heavily infested with blood-feeding insects, and there is no evidence that A. casalis mites affect woodpecker fitness.