Behavioral and endocrine correlates of dominance in captive female Jackson's hartebeest (Alcelaphus buselaphus).

For species that form dominance hierarchies, such as group-living ungulates, aggressive interactions can pose a challenge to successful captive management. For example, Jackson's hartebeest (Alcelaphus buselaphus), a rare antelope of east Africa, can be difficult to maintain in captivity because aggression within female dominance hierarchies can lead to injury and death. We quantified behavioral and endocrine correlates of dominance in a captive herd of ten female hartebeest with the goal of understanding how to minimize dangerous interactions. We observed hartebeest for 18 months in a 4-ha enclosure on St. Catherines Island, Georgia. We quantified type of agonistic behavior, initiator and recipient of the behavior, who displaced whom, and age and relative size of participants. We also used fecal steroid analysis to take weekly measurements of corticoids, a hormonal correlate of stress. Hartebeest maintained a stable, linear dominance hierarchy. Only 5.9% of interactions were reversals of established rank. Most dominance interactions were low intensity, but 17.3% of interactions carried a high risk of injury (chase, horn butt, horn clash, horn clash on knees, and head push). High-ranking individuals usually initiated interactions. Most interactions were between animals of similar rank, and animals of intermediate rank participated in the highest number of interactions. The frequency of high-intensity interactions was unrelated to rank. Rank was correlated with age, but not size. There was no relationship between rank and fecal corticoid levels. Dominance interactions in hartebeest are not a function of social instability, and the frequency of dangerous interactions is not a function of rank.

Intestinal parasites of the gopher tortoise (Gopherus polyphemus) from eight populations in Georgia.

The gopher tortoise (Gopherus polyphemus), one of five tortoise species endemic in the USA, was recently classified as a candidate for federal listing as a threatened species. Fecal samples collected from 117 tortoises from eight sites in Georgia were examined for endoparasites using a combination of sedimentation and flotation. Samples from an island population were examined for parasitic oocysts and ova only by flotation, protozoan cysts by trichrome-stained direct smear, and Cryptosporidium by direct immunofluorescence assay and ProSpecT rapid assay. A total of 99 tortoises (85, range 0-100%) was infected with pinworms (Alaeuris spp.), 47 (40, 0-86%) with cestodes (Oochorstica sp.), 34 (41, 0-74%) with Chapiniella spp., 2 (3, 0-33%) with Eimeria paynei, and a single tortoise each with a capillarid and ascarid (1%). On the island, Entamoeba was detected in one tortoise (2%) while Cryptosporidium oocysts were detected in eight (17%). In conclusion, at least eight species of parasites were detected including Cryptosporidium, a possible pathogen of tortoises. Interestingly, we detected spatial variation in the distribution of several parasites among populations suggesting additional work should be conducted across a gradient of tortoise densities, land use, and habitat characteristics.