Abstract
Hawaiian monk seals (Neomonachus schauinslandi; HMS) are endangered phocids endemic to Hawaii. Prey limitation and poor foraging success are the main threat to HMS in the Northwestern Hawaiian Islands (NWHI).1,2 In the main Hawaiian Islands (MHI), conflicts involving humans, disease, and pollution pose the greatest threat to HMS surviva.3,4 With extremely poor juvenile survival in the NWHI and increasing human-seal interactions in the MHI, the rehabilitation of sick, injured, or malnourished HMS has been identified as an important conservation strategy for this species.5-7 With the establishment of a dedicated monk seal hospital and in conjunction with the existing long-term HMS research program, 12 weaned pups and 3 yearling seals that had poor probabilities of survival were rehabilitated from 2014–2016. Initial examinations included morphometrics, hematology, serum chemistry, fecal bacterial culture, serology, blood ciguatoxin levels, and ocular, nasal, and rectal swabs for virology screening. Seals were treated for malnutrition, gastrointestinal cestodiasis, skin wounds, abscesses, and Campylobacter enteritis. Upon admission, pups weighed 27.6 ± 7.4 kg and yearlings weighed 40.8 ± 7.2 kg. Time in rehabilitation for the 8 released seals ranged from 66–198 d with weight gains of 39.3 ± 34.4 kg (range 9.4–91.5 kg). Post-release telemetry data revealed that all 8 seals were foraging until their tags stopped transmitting, and 4 of these animals have been re-sighted in good nutritional condition one year post-release. To date, these seals represent more than 1% of the entire HMS population and highlight the essential role of rehabilitation in conservation of this critically endangered species.
Acknowledgements
The authors would like to thank the staff and volunteers of The Marine Mammal Center - Ke Kai Ola for their care of the animals undergoing rehabilitation and the staff of the NOAA HMS Research Program for the rescue, transport, and release of the seals.
* Presenting author
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