Southern Right Whale (Eubalaena australis) health monitoring program at Península Valdés, Argentina: evaluating health risks affecting the recovery of Right Whales

NADIA MOHAMED; LUCIANA POZZI; LUCIANO LA SALA; LUCIANA MUSMECI; JULIAN ANDREJUK; DEE MCALOOSE; MARCELA UHART; VICTORIA ROWNTREE; MARIANO SIRONI

Cape Town, South Africa

Conferencia; 17th Biennial Conference on the Biology of Marine Mammals; 2007

Society for Marine Mammalogy

More right whales strand on the nursery ground at Península Valdés than anywhere else in the world. The Península’s large bays with gradually sloping beaches and big tides probably contribute to the high number of strandings. Tissue samples from stranded animals are valuable for monitoring the health of the population and the whales’ biology. The SRW stranding project was established in 2003 to collect information that could contribute to the conservation of right whale populations worldwide. To date, the majority (80%) of the strandings at Península Valdés have been reported by members of a stranding network maintained by the project. Between 2003 and 2006 we examined 90 calves, 6 juveniles, 10 adults and 2 individuals of unknown age class (total 108 whales). Twenty-two percent of the strandings were in fresh condition and permitted the collection of tissue samples for histopathology and/or blubber thickness measurements. All strandings in fresh condition were calves. Most of the strandings, however, were in advanced decomposition. Tissues for histopathology were collected from 30 whales (27.8%). In four years we recorded only one possible event of watercraft-induced trauma. In 2004 we recovered the skeleton of an adult whale stranded the year before with severe vertebral bone lesions. Additionally, in 2003 and 2005 the number of strandings was unusually high (31 and 46 respectively, compared to 13 in 2004 and 18 in 2006), and in 2005, five adults died within a two-week period. We report a summary of the strandings, descriptions of morphometric, blubber thickness, bacteriology and histopathology results to date, and a list of current and future research that will be undertaken with materials collected from the stranded animals. Comparisons with other populations should allow researchers to identify aspects associated with successful and failing populations and thus highlight health issues contributing to population declines.