Population dynamics of southern right whlaes at Península Valdés and Golfo San Matías Argentina: rates of increase and changes in distribution

CRESPO, ENRIQUE A.; COSCARELLA, MARIANO A.; ARIAS, MAGDALENA; SUEYRO, NICOLÁS; GONZÁLEZ, RAÚL A. C.

Cambridge - Virtual

Congreso; 68°C Annual Meeting of the International Whaling Commission; 2022

International Whaling Commission

The recent mortality of southern right whales at Península Valdés, Argentina is the highest ever recorded for the species. Understanding the causes is critical to propose management and mitigation actions. Preliminary results from glucocorticoids in baleen from stranded calves show that stress from injuries due to Kelp Gull attacks negatively affects their physiological homeostasis, potentially leading to death. Also, aerial counts show an important reduction in population rate of increase as a whole (from 7% in the past to 0.5% at present), and changes in distribution (mainly of adults) and density along the Argentine coast. The expected outcomes of this project include (1) necropsies of stranded whales during the 2018 season (June-December), (2) the collection and analysis of baleen plates to evaluate stress hormones and (3) eight aerial surveys to count whales and record their distribution in Península Valdés and in their expanded range in Golfo San Matías in 2018.