@article{borkhataria_frederick_hylton_bryan_rodgers_2008, title={A preliminary model of Wood Stork population dynamics in the southeastern United States}, volume={31}, DOI={10.1675/1524-4695(2008)31[42:APMOWS]2.0.CO;2}, abstractNote={Abstract We modeled population dynamics and extinction probabilities for the endangered Wood Stork (Mycteria americana) using count data from synoptic aerial surveys, annual measures of productivity from throughout the southeastern U.S., and survival data from satellite-tagged juveniles. Using a simple, count-based diffusion approximation approach we were able to quantify an increasing population trend since 1976. High inter-year variability resulted in wide confidence intervals and we could not eliminate the possibility of long-term population decline in spite of recently measured population increases. We also used a stage-based population matrix model to incorporate observed differences in survival rates among age classes. Fledging success, and survival of fledglings, one, and two-year-old birds were estimated using data from the satellite telemetry study. Because the survival rates of three-year-olds and adults are presently unknown, we analyzed population dynamics over a range of these values. Long-term population growth was most sensitive to changes in adult survivorship. This deterministic matrix model indicated that adult survival rates >0.94 were necessary to maintain a growing population, an estimate considerably higher than that observed in the European White Stork (Ciconia ciconia). This study underscores the need for reliable estimates of juvenile and adult survival in Wood Storks, and for a conservation focus on the factors that affect adult survival. It also provides a tool for understanding and projecting potential trajectories of the Wood Stork population in the Southeastern United States.}, journal={Waterbirds}, author={Borkhataria, R. R. and Frederick, P. C. and Hylton, R. and Bryan, A. L. and Rodgers, J. A.}, year={2008}, pages={42–49} }
 @article{hylton_frederick_fuente_spalding_2006, title={Effects of nestling health on postfledging survival of wood storks}, volume={108}, ISSN={["1938-5129"]}, DOI={10.1650/0010-5422(2006)108[0097:EONHOP]2.0.CO;2}, abstractNote={Abstract Little is known about the period between fledging and breeding in long-lived birds, including survival rates and factors affecting survival, yet this period may be critical to population regulation. We conducted health exams on 72 nestling Wood Storks (Mycteria americana) aged 4–6 weeks, and monitored survival of these birds via satellite telemetry for up to two years of age. Eighty-two percent of nestlings fitted with transmitters in 2002 (n = 33) survived to fledging. Of these fledglings (n = 27), 44% survived their first year. Second-year survival for the same cohort (n = 12) was 75%. In contrast, 50% of nestlings fitted with transmitters in 2003 (n = 34) survived to fledging, and 6% of fledglings (n = 17) survived the first year. Of the health parameters we measured in large nestlings, white blood cell count was consistently the most closely related to postfledging survival. Significantly elevated heterophil:lymphocyte ratios in 2003 coincided with the observed high colony abandonment that year. After controlling for health parameters, gender also appeared to play a significant role in predicting survival, with males at greater risk of mortality. Hematological factors and gender were both more closely associated with survival in 2003 than in 2002, suggesting these factors may play a greater role in regulating postfledging survival or, in the case of hematology, serve as indicators of poor health in less favorable years when nestling storks are exposed to multiple stressors.}, number={1}, journal={CONDOR}, author={Hylton, RA and Frederick, PC and Fuente, TE and Spalding, MG}, year={2006}, month={Feb}, pages={97–106} }