Abstract
The Peruvian population of the South American fur seal (Arctocephalus australis) has been considered in danger of local extinction since a 72% population decline caused by the 1997–1998 El Nino Southern Oscillation (ENSO).1 One of the largest rookeries for this species in Peru is located within the Punta San Juan (PSJ) reserve (15°22'S, 75°12'W). A component of current conservation efforts is focused on understanding the current health of the population. The objective of this project was to evaluate exposure to 7 pinniped pathogens in adult female fur seals (n = 29) via serology and PCR techniques, with the hypothesis that this population was naïve. The results suggest this population is naïve to canine and phocine distemper viruses (serum neutralization test), five Leptospira spp. serovars (microscopic agglutination test), and Brucella canis (card test). Immunofluorescent antibody testing for Toxoplasma gondii, Neospora caninum, and Sarcocystis neurona was also uniformly negative. PCR testing of nasal swabs for Mycoplasma spp. were positive in 37.9% (11/29) of samples. One animal was positive via card test for Brucella abortus. Antibody to SEHV-1 was identified in 85.7% (24/28) of the sampled population by serum neutralization testing. SEHV-1 titers were considered low to moderate and did not correlate with an increased total white blood cell count. Overall results indicate low to no exposure to many recognized pinniped pathogens. As Peruvian coastal development continues, bringing increased human occupancy and industrialization, the likelihood of exposure to some of these pathogens increases. The naivety of this key population of South American fur seals raises concerns about potential risk for disease introduction.
Acknowledgements
The authors wish to thank Marco Cardeña, Franco Garcia, Paulo Guerrero, Maria Jose Ganoza, and Jennifer Langan. The authors also thank the Chicago Board of Trade Endangered Species Fund and the Chicago Zoological Society for financial support of this project.
References
1. Oliveira LR, Meyer D, Hoffman J, Majluf P, Morgante J. Evidence of a genetic bottleneck in an El Nino affected population of South American fur seals, Arctocephalus australis. J Mar Biol Assoc UK. 2009;89(8):1717–1725.