Geographic Variation of Persistent Organic Pollutants in Hawaiian Monk Seals Monachus schauinslandi in the Main Hawaiian Islands
Twenty seals were outfitted with tracking devices to map their home ranges, which were then compared with the persistent organic pollutants in their serum.
Geographic variation in the levels of persistent organic pollutants was assessed in the serum of Hawaiian monk seals Monachus schauinslandi from the main Hawaiian Islands. Twenty seals were outfitted with tracking devices to map their home ranges, which were then compared with the persistent organic pollutant levels in their serum. Seals with similar ranges were shown to have similar persistent organic pollutant levels, and seals with home ranges around the island of O‘ahu had significantly higher summed polychlorinated biphenyls and polybrominated diphenyl ethers than seals around the islands of Kaua‘i and Moloka‘i. This difference was not seen for summed diphenyl-dichlorotriphenylethanes or chlordanes. Non-metric multi-dimensional scaling was used to determine if this geographic variation in serum persistent organic pollutant levels was associated with specific persistent organic pollutants, watersheds, or state land use districts. The scaling ordination revealed patterns at the island scale, rather than the finer watershed scale. Additionally, there were differences in the land use characteristics adjacent to seals’ home ranges between two islands: seals with home ranges around O‘ahu had a high percentage of area adjacent to urban land use districts, and seals with home ranges around Moloka‘i had a high percentage of area adjacent to rural and agricultural land use districts. Integration of serum persistent organic pollutant levels and seal home ranges revealed geographic patterns that will help assess the risk of persistent organic pollutants to individual seals. The integrated approach highlighted in this study is applicable to other marine wildlife exposed to local and non-point pollutants.
Lopez J, Hyrenbach KD, Littnan C, Ylitalo GM. 2014. Geographic variation of persistent organic pollutants in Hawaiian monk seals Monachus schauinslandi in the main Hawaiian Islands. Endangered Species Research 24:249-262. https://doi.org/10.3354/esr00602.