Abstract

Parasites are known to have a significant impact on marine mammal health.^1,2 Though the parasites of stranded weanling northern elephant seals (Mirounga angustirostris) are well documented, very little work has investigated the types of parasites commonly found in healthy juvenile, sub-adult and adults of the species.^2-5 The objective of this study is to provide pilot data about the parasites endemic to the northern elephant seal population of Año Nuevo State Park. Northern elephant seals feces collected from Año Nuevo were screened for parasites over the course of the molting season, in spring of 2015. Throughout the season, a total of 20 fecal samples were collected opportunistically off the beach from individuals of both genders and all age classes over one year old. The samples underwent a fecal floatation and were surveyed for parasites. In addition to samples from specific individuals, random non-individual specific fecal samples were collected and analyzed. A number of parasites were found, including Parafilaroides sp., Anisakis sp., Contracaecum sp., as well as trematodes and cestodes. These results offer insights into current understandings of host-parasite relationships of northern elephant seals. These results also begin to build a baseline of normal parasite loads in apparently healthy individuals and begin to lay the ground work for future screening for potentially significant pathogenic parasites.

Acknowledgements

The authors would like to thank all the staff and volunteers at The Marine Mammal Center and the other students, both graduate and undergraduate, in the Costa lab at UCSC.

* Presenting author
+ Student presenter

Literature Cited

1.  Dailey MD. Parasitic diseases. In: Dierauf LA, Gulland FMD, eds. CRC Handbook of Marine Mammal Medicine. 2nd edition. CRC Press, LLC.; 2001:357–374.

2.  Geraci JR, St. Aubin DJ. Effects of parasites on marine mammals. Int J Parasitol. 1987;17(2):407–414. Retrieved from www.ncbi.nlm.nih.gov/pubmed/24271151.

3.  Colegrove KM, Greig DJ, Gulland FMD. Causes of live strandings of northern elephant seals (Mirounga angustirostris) and Pacific harbor seals (Phoca vitulina) along the Central California coast, 1992–2001. Aquat Mamm. 2005;31(1):1–10. http://doi.org/10.1578/AM.31.1.2005.1.

4.  Gulland FMD, Beckman K, Spraker T, Dailey M. Nematode (Otostrongylus circumlitus) infestation of northern elephant seals (Mirounga angustirostris) along the Central California cost. Mar Mamm Sci. 1997;13:446–458.

5.  Lyons ET, Kuzmina TA, Spraker TR, Jaggi N, Costa DP, Crocker DE, Tift MS. Parasitological examination for presence of hookworms (Uncinaria spp.) in northern elephant seals (Mirounga angustirostris) at Año Nuevo State Reserve, California (2012). Parasitol Res. 2012;111(4):1847–1850. http://doi.org/10.1007/s00436-012-2919-5.