@article{collazo_krachey_pollock_perez-aguilo_zegarra_mignucci-giannoni_2019, title={Population estimates of Antillean manatees in Puerto Rico: an analytical framework for aerial surveys using multi-pass removal sampling}, volume={100}, ISSN={["1545-1542"]}, DOI={10.1093/jmammal/gyz076}, abstractNote={Effective management of the threatened Antillean manatee (Trichechus manatus manatus) in Puerto Rico requires reliable estimates of population size. Estimates are needed to assess population responses to management actions, and whether recovery objectives have been met. Aerial surveys have been conducted since 1976, but none adjusted for imperfect detection. We summarize surveys since 1976, report on current distribution, and provide population estimates after accounting for apparent detection probability for surveys between June 2010 and March 2014. Estimates in areas of high concentration (hotspots) averaged 317 ± 101, three times higher than unadjusted counts (104 ± 0.56). Adjusted estimates in three areas outside hotspots also differed markedly from counts (75 ± 9.89 versus 19.5 ± 3.5). Average minimum island-wide estimate was 386 ± 89, similar to the maximum estimate of 360 suggested in 2005, but fewer than the 700 recently suggested by the Puerto Rico Manatee Conservation Center. Manatees were more widespread than previously understood. Improving estimates, locally or island-wide, will require stratifying the island differently and greater knowledge about factors affecting detection probability. Sharing our protocol with partners in nearby islands (e.g., Cuba, Jamaica, Hispaniola), whose populations share genetic make-up, would contribute to enhanced regional conservation through better population estimates and tracking range expansion.}, number={4}, journal={JOURNAL OF MAMMALOGY}, author={Collazo, Jaime A. and Krachey, Matthew J. and Pollock, Kenneth H. and Perez-Aguilo, Francisco J. and Zegarra, Jan P. and Mignucci-Giannoni, Antonio A.}, year={2019}, month={Jul}, pages={1340–1349} } @article{boone_merrick_krachey_2014, title={A Hellinger distance approach to MCMC diagnostics}, volume={84}, number={4}, journal={Journal of Statistical Computation and Simulation}, author={Boone, E. L. and Merrick, J. R. W. and Krachey, M. J.}, year={2014}, pages={833–849} } @article{porter_deperno_krings_krachey_braham_2014, title={Vegetative Impact of Feral Horses, Feral Pigs, and White-tailed Deer on the Currituck National Wildlife Refuge, North Carolina}, volume={79}, ISSN={["1938-4386"]}, DOI={10.2179/13-037}, abstractNote={ABSTRACT  The Currituck National Wildlife Refuge (CNWR) in North Carolina is inhabited by feral horses (Equus caballus), feral pigs (Sus scrofa), and white-tailed deer (Odocoileus virginianus). The impact of these species on the vegetation of CNWR is unknown. To assess impact, we created two replicate exclosure plots within maritime forests, brackish marshes, and maritime grasslands. An electric fence divided each habitat into two sections: including or excluding horses. On each side of the electric fence within each habitat, we sampled three different 5 × 5 m plots (i.e., 36 plots). The first was a fenced exclosure 3 m high, the second a fenced exclosure raised 1 m above the ground and extended to 3 m, and the third, a control, was not fenced. Within plots, we created two 1 m transects, and randomly selected and tagged grasses, forbs, shrubs, and trees. We measured the distances from base to tip of herbs and from branching point to terminal bud in shrubs. We used a linear model to analyze plant growth rate. We used a length ratio adjusted by the number of days as the response variable. Out of 1,105 tagged plants, we detected 87 disturbances; 80 where horses were present and 7 where horses were excluded. Overall, horses were responsible for 84% of disturbances. Most disturbances occurred in brackish marshes on Schoenoplectus pungens. We detected a significant effect of exclosure treatment on plant growth rate where horses were present (p = 0.035), but not where they were excluded (p = 0.32).}, number={1}, journal={CASTANEA}, author={Porter, Kimberly M. and DePerno, Christopher S. and Krings, Alexander and Krachey, Matthew and Braham, Richard}, year={2014}, month={Mar}, pages={8–17} } @article{blackman_deperno_heiniger_krachey_moorman_peterson_2011, title={Effects of crop field characteristics on nocturnal winter use by American woodcock}, volume={76}, ISSN={0022-541X}, url={http://dx.doi.org/10.1002/JWMG.254}, DOI={10.1002/jwmg.254}, abstractNote={Abstract}, number={3}, journal={The Journal of Wildlife Management}, publisher={Wiley}, author={Blackman, Emily B. and Deperno, Christopher S. and Heiniger, Ron W. and Krachey, Matthew J. and Moorman, Christopher E. and Peterson, M. Nils}, year={2011}, month={Nov}, pages={528–533} }