Parasites of harbor seals (Phoca vitulina) in Glacier Bay and Prince William Sound, Alaska.

摘要

This study was conducted to assess the parasite prevalence in the faeces and tracheal swabs of harbor seals (Phoca vitulina) of both sexes from Price William Sound (PWS) and Glacier Bay (GB), Alaska, USA between 2004 and 2006. Faecal samples were collected from seals which defaecated from on boat decks. The seals were grouped into adults (n=6), subadults (n=3) and juveniles (n=15) using morphometric methods. Additional faecal samples were collected from haul-out sites in both PWS (n=67)and GB (n=257). DNA was extracted from faecal samples to identify the sex of the seals. Worms were collected from faecal samples by using sieves. Results revealed that adult worms were present in 20% of 271 samples from GB and 43% of 77 samples from PSW. Tracheal swabs showed lungworms(Parafilaroides gymnurus and Otostronylus circumlitus) from 46 and 73% seals from PWS and GB, respectively. The most prevalent faecal parasite was Anisakis. It was observed that the parasites were high for both sexes and regions. The prevalence of parasites among the different age groups were similar among age classes and areas and included Anisakis, Contracaecum sp., and P. decipiens. Anisakis sp. was found in 100, 66 and 93% of the adult, subadult and juvenile seals, respectively. It is recommended that other studies regarding other infectious agents should be included in order to determine their effects on seal population.Digital Object Identifier http://dx.doi.org/10.1111/j.1748-7692.2009.00355.x