Influence of Chinese Tallow Infestation on Winter Bird Community along Lanana Creek Basin

Exotic invasive plant species are among the greatest threats to biodiversity and persistence of rare wildlife species in the United States. These plants compete with native plants, causing extinctions or severe reductions in native populations. They may also affect wildlife through loss of preferred food items or changes in vegetation structure. Chinese tallow tree (Triadeca sebifera) is one of the most important and widespread exotic plants in the Southeast. Although impacts of Chinese tallow on vegetation communities are well studied, impacts on native wildlife are less well understood. This study explored the interaction between native wildlife and Chinese tallow infestation in the Lanana Creek basin in Nacogdoches, TX

Daily Movements of Female White-tailed Deer Relative to Parturition and Breeding

To assess how white-tailed deer (Odocoileus virginianus) herd demographics influence reproductive behaviors, we examined 24-h diel movements of female whitetailed deer relative to parturition and breeding in a low-density population with a near even sex ratio at the Savannah River Site (SRS), South Carolina. We conducted a series of intensive, 24-h radio-tracking periods of 13 females during spring and fall 2002. We compared daily range (ha), rate of travel (m/h), and distance between extreme daily locations (m), among the periods of pre-parturition and post-parturition and pre-, peak-, and post-rut. From pre-parturition to post-parturition, we observed decreases in diel range size (–38.2%), distance between extreme diel locations (–17.0%), and diel rate of travel (–18.2%). Diel range size, distance between extreme diel locations, and diel rate of travel during the pre-rut and rut exceeded those observed during post-rut. We further identified substantial increases in mobility during 12 24-h diel periods for eight females during our fall monitoring. Our data suggest that female white-tailed deer reduce mobility post-fawning following exaggerated movements during pre-parturition. Furthermore, despite a near equal sex ratio, estrous does may be required to actively seek potential mates due to low population density

Effects of Controlled Dog Hunting on Movements of Female White-tailed Deer

Understanding the responses of white-tailed deer (Odocoileus virginianus) to controlled dog hunting can aid in the effective implementation of canine-assisted population management strategies. We examined the 24-h diel movements of 13 radio-collared female deer exposed to dog hunting on the Savannah River Site (SRS) near Aiken, South Carolina, where regulated dog hunting has occurred since 1965. We compared diel home range size, rate of travel, and distance between extreme diel locations before, during, and after hunts from 14 September-14 December 2002. Die1 home range size (F2,91= 7.71, P \u3c 0.001) and distance between extreme diel locations (F2,9l= 6.78, P = 0.002) on hunt day were greater than 10-day pre- and post-hunt periods. There was no difference between pre-and post-hunt diel home range size (F2,91= 7.71, P = 0.999) and distance between extreme diel locations (F2,91= 6.78, P = 0.704). Rate of travel (F2,91=2.74, P = 0.070) did not differ among the pre-, hunt day, and post-hunt periods. In 8 of 15 monitoring periods of individual deer during hunts, deer moved outside the periphery of their fall home range. The mean distance deer moved outside of their fall home range boundary was 0.8 krn (SE = 0.2 km) and all returned within 13 hours. Our data suggest short-term, controlled dog hunting has little long-term effect on adult, female white-tailed deer movement on the SRS. Because deer did not leave the hunt area, the effectiveness of such hunts may be increased by extending their duration

SPATIALLY EXPLICIT MODEL OF AREAS BETWEEN SUITABLE BLACK BEAR HABITAT IN EAST TEXAS AND BLACK BEAR POPULATIONS IN LOUISIANA, ARKANSAS, AND OKLAHOMA

Although black bears (Ursus americanus, Ursus americanus luteolus) were once found throughout the south-central United States, unregulated harvest and habitat loss resulted in severe range retractions and by the beginning of the twentieth century populations in Oklahoma, Louisiana, Texas and Arkansas were nearing extirpation. In response to these losses, translocation programs were initiated in Arkansas (1958-1968 & 2000-2006) and Louisiana (1964-1967 & 2001-2009). These programs successfully restored bears to portions of Louisiana and Arkansas, and, as populations in Arkansas began dispersing, to Oklahoma. In contrast, east Texas remains unoccupied despite the existence of suitable habitat in the region. To facilitate the establishment of a breeding population in east Texas, I sought to identify suitable habitat which bears could use for dispersal between known bear locations in Louisiana, Arkansas and Oklahoma and the east Texas recovery units. I utilized Maxent, a machine learning software, to model habitat suitability in this region. I collected known black bear presence locations (n=18,241) from state agencies in Louisiana, Oklahoma, Arkansas and east Texas and filtered them to reduce spatial autocorrelation (n=664). I also collected spatial data sets based on known black bear ecology to serve as environmental predictor variables. The model was developed at 30-m resolution and encompassed 417,076 km 2. The final model was selected to minimize model over-fitting while maintaining a high test Area Under the Receiver Operating Curve (AUC TEST)score. For final model interpretation and analysis, I used the 10th percentile training threshold available in Maxent which excludes the lowest 10% of predicted presence suitability scores from the binary predictive map, thus resulting in a more conservative predictive map. The final 10th percentile model predicted 43.7% of the pixels in the study area as suitable and 53.7 % percent of the pixels identified as potential recovery units by Kaminski et al. (2013, 2014) as suitable. To focus management efforts, I identified three movement zones with a high proportion of suitable habitat within which connectivity analyses were performed. Suitable patches greater than or equal to 12 km2 were classified within ArcGIS as stepping stone patches. Buffers of 3,500 m were generated around these patches to determine the level of functional connectivity in each zone. The final Maxent model confirmed that suitable bear habitat exists between source populations and the east Texas recovery units. The importance of percent of mast producing forest, percentage of cultivated crops and percentage of protected lands reflect what is known about basic bear biology and ecology. Furthermore, 153 stepping stone patches were identified within the movement zones, demonstrating that there is a reasonable chance of bears naturally dispersing to east Texas using the habitat identified in this study. Thus, protection of existing bear habitat and the stepping stone patches identified in this study should be a priority for managers seeking to facilitate natural bear recolonization of east Texas