Free-ranging pet cats (Felis catus) frequently kill wildlife but also return live prey to their owners. This raises welfare concerns if live animals released by cat owners subsequently die, since this is preventable, eg through prompt euthanasia. To estimate the mortality rate of birds released alive by cat owners, we examined the fates of 3,597 cat-attacked individuals submitted to four RSPCA wildlife centres in the UK. Individuals from 64 species were received but most cases (77%) involved just seven species commonly found in urban areas. The overall mortality rate (based on all individuals received at centres, ie including those which perished in transport, those which were euthanased on arrival and those which were admitted for care after having been triaged) was 78%; the post-admittance mortality rate (n = 2,070 birds admitted for care) was 62%. On average, individuals that perished (n = 2,798) survived for 3.0 days before dying or being euthanased. Juveniles were more likely to survive to release than adults, possibly because their small size means they are less likely to receive injuries that are ultimately fatal. Extrapolating from the limited data currently available, and applying conservative estimates at each stage, we estimate that a minimum of 0.3 million birds are released annually by cat owners but subsequently die. Substantial welfare improvements could be achieved if owners were more prepared to adopt strategies to limit hunting behaviour (eg fitting cats with collars and bells) and if owners and rehabilitators were able to effectively identify individuals with fatal injuries. The latter will require studies that quantify the effects of identifiable physical injuries on the likelihood of survival to release, in order to establish effective triage criteria.

The hunting behaviour of leopard seals Hydrurga leptonyx was monitored opportunistically at Seal Island, South Shetland Islands, during the austral summers from 1986/87 to 1994/95. Leopard seals used several methods to catch Antarctic fur seal pups Arctocephalus gazella and chinstrap penguins Pygoscelis antarctica, and individuals showed different hunting styles and hunting success. One to two leopard seals per year were responsible for an average of 60% of observed captures of fur seal pups. Leopard seals preyed on penguins throughout the summer, but preyed on fur seal pups only between late December and mid-February. Hunting behaviour differed significantly between different locations on the island; fur seals were hunted only at one colony, and penguins were hunted in several areas. The relative abundance of prey types, size of prey in relation to predator, and specialization of individual leopard seals to hunt fur seal prey probably influence individual prey preferences among leopard seals. On five occasions, two leopard seals were seen together on Seal Island. Possible interpretations of the relationship between the inter-acting leopard seals included a mother–offspring relationship, a consorting male–female pair, and an adult leopard seal followed by an unrelated juvenile. In two incidents at Seal Island, two leopard seals were observed interacting while hunting: one seal captured fur seal pups and appeared to release them to the other seal. Observations of leopard seals interacting during hunting sessions were difficult to confirm as co-operative hunting, but they strongly implied that the two seals were not agonistic toward one another. The hunting success of individual leopard seals pursuing penguins or fur seals is probably high enough for co-operative hunting not to become a common hunting strategy; however, it may occur infrequently when it increases the hunting productivity of the seals.

African wild dogs Lycaon pictus have been extirpated across most of West and central Africa, and greatly depleted in eastern and southern Africa. Given an urgent need for population recovery, especially in West and central Africa, this paper discusses the possibilities for using reintroduction to re-establish wild dog populations. Reintroduction is probably now technically possible, as long as release groups include wildcaught animals; several past attempts failed because captive-reared animals lacked skills needed to survive in the wild. However, reintroduction has only a limited role to play in wild dog conservation. Ideally, it should involve animals of the appropriate local genotype. Limited genetic data indicate that wild dogs from West and central Africa may be distinct from those in eastern and southern Africa. Because there are no wild dogs with West or central African genotypes in captivity, and no wild populations in the region large enough to be harvested for translocation, future reintroductions might have to use animals with non-native genotypes. In addition, there appear to be no suitable sites for wild dog reintroduction in West or central Africa, and few in eastern and southern Africa. Releases currently planned in the Republic of South Africa will be locally valuable, but will not establish a population likely to remain viable without intensive management in perpetuity. For these reasons, protecting remaining wild dog populations currently represents a better investment than any attempt at reintroduction.