Characteristic "neck collar" injuries in Australian sea lions (Neophoca cinerea) caused by marine debris.

An adult male Australian sea lion (Neophoca cinerea) presented with a deep, almost circumferential, incised wound around the neck caused by a noose formed by a single strand of green nylon rope. The wound extended 4-5 cm deeply through the skin and blubber into skeletal muscle, predominantly on the dorsal surface and left side, but had not involved the airway or major vessels. The edges of the wound were sharply incised and oozing blood with a granulating infected base. The rope was removed and the wound debrided of necrotic tissues and irrigated with disinfectant. Antibiotic and rehydration therapy were successful and the seal was released after 2 weeks of treatment. Entanglement injuries such as "neck collars" have characteristic features, are increasing in incidence and often have lethal outcomes. This type of injury may significantly impact upon populations of pinnipeds in the wild.

Neonatal mortality in New Zealand sea lions (Phocarctos hookeri) at Sandy Bay, Enderby Island, Auckland Islands from 1998 to 2005.

As part of a health survey of New Zealand sea lions (Phocarctos hookeri) on Enderby Island, Auckland Islands (50 degrees 30'S, 166 degrees 17'E), neonatal mortality was closely monitored at the Sandy Bay colony for seven consecutive years. Throughout the breeding seasons 1998-99 to 2004-05, more than 400 postmortem examinations were performed on pups found dead at this site. The primary causes of death were categorized as trauma (35%), bacterial infections (24%), hookworm infection (13%), starvation (13%), and stillbirth (4%). For most pups, more than one diagnosis was recorded. Every year, two distinct peaks of trauma were observed: the first associated with mature bulls fighting within the harem and the second with subadult males abducting pups. In 2001-02 and 2002-03, epidemics caused by Klebsiella pneumoniae increased mortality by three times the mean in nonepidemic years (10.2%). The increased mortality was attributed directly to acute suppurative infection due to the bacterium and also to an increase in traumatic deaths of debilitated pups. Parasitic infection with the hookworm Uncinaria spp. was a common finding in all pups older than three weeks of age and debilitation by the parasite may have contributed to increased susceptibility to other pathogens such as Klebsiella sp. or Salmonella sp. This study provides valuable quantitative data on the natural causes of neonatal mortality in New Zealand sea lions that can be used in demographic models for management of threatened species.