Male chimpanzees produce a species‐typical call, the pant hoot, to communicate to conspecifics over long‐distances. Calls given by males from the well‐known Gombe and Mahale populations typically consist of four different phases: an introduction, build‐up, climax, and let‐down. Recent observations suggest that chimpanzees living in the Kibale National Park, Uganda, consistently give calls that lack a build‐up and are thus qualitatively distinguishable acoustically from those made by other East African conspecifics. We analyzed additional recordings from Mahale and Kibale to re‐examine geographic variation in chimpanzee calls. Results indicate that males from both sites produce pant hoots containing all four parts of the call. Calls made by chimpanzees from the two populations, however, differ in quantitative acoustic measures. Specifically, males at Kibale initiate their calls with significantly longer elements and build‐up over briefer periods at slower rates than individuals from Mahale. Kibale males also deliver acoustically less variable calls than chimpanzees at Mahale. Although climax elements do not differ between populations in any single acoustic feature, discriminant function analysis reveals that acoustic variables can be used in combination to assign calls to the correct population at rates higher than that expected by chance. Ecological factors related to differences in habitat acoustics, the sound environment of the local biota, and body size are likely to account for these observed macrogeographic variations in chimpanzee calls. Am. J. Primatol. 47:133–151, 1999. © 1999 Wiley‐Liss, Inc.

Lobomycosis (lacaziosis) is a chronic fungal disease of the skin that affects only dolphins and humans. Previous studies have shown a high prevalence of lobomycosis in bottlenose dolphins (Tursiops truncatus) from the Indian River Lagoon, Florida (IRL). We studied the occurrence and distribution of lobomycosis in the IRL using photo-identification survey data collected between 1996 and 2006. Our objectives were to (1) determine the sensitivity and specificity of photo-identification for diagnosis of lobomycosis in free-ranging dolphins; (2) determine the spatial distribution of lobomycosis in the IRL; and (3) assess temporal patterns of occurrence. Photographs from 704 distinctly marked dolphins were reviewed for skin lesions compatible with lobomycosis. The presumptive diagnosis was validated by comparing the results of photographic analysis with physical examination and histologic examination of lesion biopsies in 102 dolphins captured and released during a health assessment and 3 stranded dolphins. Twelve of 16 confirmed cases were identified previously by photography, a sensitivity of 75%. Among 89 dolphins without disease, all 89 were considered negative, a specificity of 100%. The prevalence of lobomycosis estimated from photographic data was 6.8% (48/704). Spatial distribution was determined by dividing the IRL into six segments based on hydrodynamics and geographic features. The prevalence ranged from <1% in the Mosquito Lagoon to 16.9% in the south Indian River. The incidence of the disease did not increase during the study period, indicating that the disease is endemic, rather than emerging. In summary, photo-identification is a useful tool to monitor the course of individual and population health for this enigmatic disease.

Photo-identification surveys conducted between 2002 and 2005 were used to determine dolphin home ranges and site fidelity within the Indian River Lagoon (IRL), Florida. The IRL was divided into six segments based on hydrodynamics and geographic features for purposes of characterization. Among the 615 dolphins with identifiable dorsal fins, 339 had > or =6 sightings and were used in segment and linear range analyses. The majority (98%) of dolphins were seen in < or =3 consecutive segments (331/339); of these, 44% (144/331) occurred in two segments, and 33% (109/331) in one segment. No dolphins were observed in all six segments. The largest number of dolphins was sighted in segment 1C (North Indian River). However, the highest density of dolphins was found in segment 2 (North-Central Indian River). Re-sighting rates for dolphins with > or =6 sightings ranged from 2.8 to 8.7 times observed. The mean linear home range varied from 22 to 54 km. Distributional analyses indicated that at least three different dolphin communities exist within the IRL: Mosquito Lagoon, and the North and South Indian River. No statistically significant correlations were found between the total number or density per km(2 )of dolphins and surface water area, salinity, or contaminant loads within segments of the lagoon. These results suggest that dolphins do not selectively avoid areas with relatively unfavorable water quality. IRL dolphins should be studied on smaller spatial scales than currently practiced, and potential anthropogenic impacts should be evaluated based on geographic partitioning.