Radio-tracking studies of ringtail possums (Pseudocheirus peregrinus) were carried out in Ku-ring-gai Chase National Park at its border with suburban Sydney. Hand-reared and relocated ringtail possums released into the study site survived an average of 101 days and wild ringtail possums resident in the study area survived an average 182 days. Of the 118 individuals whose fates were determined, all but eight were killed by predators, 52% by foxes and 29% by cats. Within the study area both introduced and wild ringtail possums used dreys (nests) more frequently than tree hollows, and nests on the ground were used about 7% of the time.

Sea turtle stranding events provide an opportunity to study drivers of mortality, but causes of strandings are poorly understood. A general turtle carcass oceanographic drift model was developed to estimate likely mortality locations from coastal sea turtle stranding records. Key model advancements include realistic direct wind forcing on carcasses, temperature driven carcass decomposition and the development of mortality location predictions for individual strandings. We applied this model to 2009-2014 stranding events within the Chesapeake Bay, Virginia. Predicted origin of vessel strike strandings were compared to commercial vessel data, and potential hazardous turtle-vessel interactions were identified in the southeastern Bay and James River. Commercial fishing activity of gear types with known sea turtle interactions were compared to predicted mortality locations for stranded turtles with suggested fisheries-induced mortality. Probable mortality locations for these strandings varied seasonally, with two distinct areas in the southwest and southeast portions of the lower Bay. Spatial overlap was noted between potential mortality locations and gillnet, seine, pot, and pound net fisheries, providing important information for focusing future research on mitigating conflict between sea turtles and human activities. Our ability to quantitatively assess spatial and temporal overlap between sea turtle mortality and human uses of the habitat were hindered by the low resolution of human use datasets, especially those for recreational vessel and commercial fishing gear distributions. This study highlights the importance of addressing these data gaps and provides a meaningful conservation tool that can be applied to stranding data of sea turtles and other marine megafauna worldwide.

Human-induced mortality of marine animals is a complex issue and the health of animals prior to human interaction is often questioned. We reviewed 74 cases of loggerhead turtles in the mid-Atlantic region of the US to determine whether fresh, dead loggerhead turtles that died from acute vessel or fishery interaction (acute VI/FI) were healthy animals prior to human-induced mortality. We used the presence of significant underlying pathology to determine health status and compared the body condition and adipose stores with turtles that died from other causes. We qualitatively and quantitatively assessed body condition using images, morphometrics, mass dissection data, % lipid and % triacylglycerol in the adipose tissue. We used the quantitative indices to validate the qualitative index. Acute VI/FI turtles were significantly less likely to have significant lesions indicating compromised health compared with turtles that died from other causes (χ 2 = 12.9012, df = 1, p = 0.0003). There was a significant relationship between qualitative body condition and cause of death category, with acute VI/FI turtles more likely to exhibit normal body condition than turtles that died from other causes (χ 2 = 18.879, df = 2, p < 0.0001). Values for 3 quantitative indices were significantly higher for acute VI/FI turtles compared with other causes of death, while 3 others were not different across turtles, most likely because there were some healthy turtles in the 'other' cause of death category. Our results suggest that the majority of acute VI/FI loggerhead turtles represented normal, healthy turtles in the population and were not compromised prior to human-induced mortality.

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