Abstract: Studies on three species of big cats at Dublin Zoo have led to firm conclusions about the effects of certain forms of enrichment, some of which will be presented here. Lions, jaguars, and snow leopards were studied over two years and their behaviours quantified using focal animal sampling during selected hours during daylight. By comparison of these activity budgets with and without the enrichments being present, it was possible to identify the exact behavioural changes caused by each enrichment method, and to quantify these changes. In this contribution we present results showing that the presence of a platform in both lion and jaguar enclosures dramatically reduced stereotypic pacing behaviour. We will demonstrate that the effects of short term enrichment devices may have a wide range of effects on behaviours which outlast the presence of the stimulus. For instance scents added to the cage, or food/play items such as horse hides, hidden fish or ice-blocks often reduce pacing and increase resting later in the day, even after the cats have ceased using the enrichment items. This reduction in pacing and increase in resting time often meant that the amount of the enclosure used per hour was actually reduced with the presence of new stimuli, as result opposite to what might have been expected. The results of these studies will be discussed in relation to effective animal management.

Abstract: In the 1960s, the endangered snow leopard was locally extirpated from the Sagarmatha (Mt. Everest) region of Nepal. In this Sherpa-inhabited high Himalaya, the flourishing tourism since the ascent of Mt Everest in 1953, has caused both prosperity and adverse impacts, the concern that catalyzed the establishment of Mt. Everest National Park in the region in 1976. In the late 1980s, there were reports that some transient snow leopards may have visited the area from adjoining Tibet, but no biological surveys exist to confirm the status of the cats and their prey. Have snow leopards finally returned to the top of the world? Exploring this question was the main purpose of this research project. We systematically walked altogether 24 sign transects covering over 13 km in length in three valleys, i.e. Namche, Phortse and Gokyo, of the park, and counted several snow leopard signs. The results indicated that snow leopards have made a comeback in the park in response to decades of protective measures, the virtual cessation of hunting and the recovery of the Himalayan tahr which is snow leopard's prey. The average sign density (4.2 signs/km and 2.5 sign sites/km) was comparable to that reported from other parts of the cats' range in the Himalaya. On this basis, we estimated the cat density in the Everest region between 1 to 3 cats per 100 sq km, a figure that was supported by different sets of pugmarks and actual sightings of snow leopards in the 60 km2 sample survey area. In the study area, tahr population had a low reproductive rate (e.g. kids-to-females ratio, 0.1, in Namche). Since predators can influence the size and the structure of prey species populations through mortality and through non-lethal effects or predation risk, snow leopards could have been the cause of the population dynamics of tahr in Sagarmtha, but this study could not confirm this speculation for which further probing may be required.

Abstract: Liver tissues from 126 captive cheetah were evaluated by light microscopy and histochemistry; eight animals were evaluated by electron microscopy. The main hepatic lesion, a vascular lesion resembling veno- occlusive disease (VOD) of the liver and characterized by subendothelial fibrosis and proliferation of smooth muscle-like cells in the central veins, was seen in 60% of the sexually mature cheetah. Although this hepatic vascular lesion was seen in cheetah as young as 1 year of age, the most severe lesions, usually associated with liver failure, were found in cheetah between the ages of 6 and 11. There was no sex predisposition, and in approximately 40% of the VOD cases, liver disease was not suspected clinically or at necropsy. VOD was found in other felidae, especially in the snow leopard. High levels of vitamin A in livers, as well as in diets of the cheetah, could be a contributing factor in the development of VOD in some groups of cheetah.