Predation ecology of large sympatric carnivores, tiger, leopard and dhole, as influenced by available wild ungulates, chital, sambar, nilgai, gaur and wild pig, were studied between January 2007 and June 2010 in a tropical deciduous forest of Central India. Both line transect and vehicle transect methods were used to estimate population structure and sex ratios of wild ungulates. The observed adult sex ratio (female:male) was found to be skewed towards females for all ungulates. A total of 123 tiger kills were recorded in the cold season and 162 in the hot season, 32 leopard kills were recorded during the cold season and 48 during the hot season and 32 dhole kills were recorded in the cold season and 55 in the hot season. The age–sex class distribution of each ungulate species in the kill data was compared with the corresponding population age–sex distribution recorded from line transects and vehicle transects. All three large carnivores preferred medium-sized prey species, e.g. chital. A significant difference was observed when comparing different health conditions of prey species predated by the three large carnivores. The observed difference in prey choice as per their body size is a strategy adopted by large carnivores to partition prey resources, thus increasing the potential to avoid intra-guild competition.

Although the harbour seal (Phoca vitulina vitulina) is relatively common in coastal waters of the Republic of Ireland, it remains largely unstudied. Issues including potential interactions with coastal fisheries and the occurrence of phocine distemper virus outbreaks in 1988 and 2002 have highlighted the need to increase our knowledge of the ecology of these animals. The diet of harbour seals was investigated using a combination of approaches: hard-part analysis of scat contents and fatty-acid analysis. A total of 102 scat and 13 blubber samples were collected from two locations in Ireland and were analysed following standard methodologies. Results from scat analysis indicate that the seals are opportunistic, generalist feeders, and probably consume prey in relation to its availability. Eighteen prey species were identified, with sandeels (Ammodytidae spp.) constituting 55% of the prey items by number. Biomass of prey was reconstructed using otolith-length regression equations, with and without the application of digestion correction factors and sole (Solea solea) (16.1%), sandeels (15.2%), and Trisopterus species (12.4%) were found to be the most important species by weight. Rarefraction curves were used to determine prey species diversity on a sample site basis and we used accumulation curves to ascertain whether sampling was sufficient on a site basis. Sixty-four fatty acids were isolated from the blubber and analysis of the fatty-acid profiles revealed the possible influence of season, seal weight and sex on the seals' long-term diet. Some of the prey species recorded in the diet overlap with commercially and recreationally caught fish species in Ireland; however, there was little overlap with marketed size-ranges.

Many small carnivores include rodents in their diet. However, due to varying evolutionary strategies, carnivores differ in their metabolism and energy requirements. Hence, comparisons of diet between carnivores would be more meaningful if the body size and energetics of the predators are considered. The diet of three small carnivores (jungle cat Felis chaus; caracal Caracal caracal; golden jackal Canis aureus) from a semi-arid part of western India was studied through scat analysis, and the importance of rodents in their diet was estimated as a percentage of their daily energy requirement. Although percentage frequency in scats and biomass consumption showed rodents to be equally important to all three carnivores, energy calculations showed that rodents were more important as prey for the felids than the jackal. Up to 70% of the daily metabolizable energy in felids was obtained from rodents, as compared to 45% in the jackal. Rodents are generally viewed as pests, and their importance to the small carnivore community is overlooked. Change in land use over the decades in the arid/semi-arid tract of western India has led to several adverse as well as favourable modifications in rodent assemblages, which could influence the persistence of species like the caracal and jungle cat in this region, that largely depend on rodents for their survival.

American mink Mustela vison are an invasive species in many parts of the world (e.g. Europe, Iceland and South America) and in many of these areas they are a threat to the native wildlife. It is therefore important to establish a reliable and efficient method to estimate their relative abundance in order to manage their populations. In this study, the use of surveys of signs (scats and footprints) as a way to estimate the relative abundance of American mink was evaluated. Populations of mink in three areas of England were studied to evaluate the impact of three factors (surveyor, marking places and month) on the probability of deposition and detection of signs. Among these factors only month had a significant effect. In the second part of the study, sign surveys were compared with live trapping and it was found that the proportion of sections with mink signs was only loosely correlated to the abundance of mink as estimated from live trapping. In conclusion, this study suggests that, provided that surveyors are trained, that there is a sufficient number of marking places in each section, and that the surveys are carried out in comparable seasons, sign surveys are an appropriate way to monitor the relative abundance of mink. Sign surveys are better than trapping when it is necessary to monitor mink populations over large areas because they are less time consuming, require less manpower and are cheaper.

Charismatic mammals remain a linchpin in attracting publicity and funds for the conservation of native habitats and organisms. Unfortunately, the same animals are frequently scarce and difficult to survey. For many, confirming their presence through faecal surveys is the only cost-effective approach. Here we show that, contrary to received opinion, expert naturalists fail reliably to distinguish pine marten Martes martes faeces (‘scats’) from those of foxes Vulpes vulpes. Moreover, their judgement fails completely when the animals and their scats are at their most scarce. This unexpected result from such a well-studied species has important implications for the monitoring of endangered mammals. We recommend that in the future, a multi-evidence approach should be adopted to monitor elusive mammals, involving DNA methods, cast hair identification, camera traps, and non-leading ‘sighting’ questionaires. For national surveys, it may soon become cost-effective to screen large numbers of samples using microarray technology.