Long-Term Strategies for Studying Rare Species: Results and Lessons from a Multi-Species Study of Odontocetes Around the Main Hawaiian Islands

English:

Context. Funding agencies are often unlikely to fund research on rarely-encountered species and limited time is usually spent with such species when they are not the focus of research. Thus, knowledge of these species often lags behind their encounter rates. Aims. To gain information on rarely-encountered odontocetes in Hawai‘i while simultaneously studying common ones. Methods. During a long-term small-boat based study, we prioritized time spent with rarely encountered species, collecting photos and biopsy samples, and satellite tagging. Sample sizes were augmented with photo contributions from members of the public and other researchers, and genetic samples from stranded animals and other researchers. Results from genetic and tag data analyses were interpreted in the context of social network placement and re-sighting histories. Key results. Pygmy killer whales (Feresa attenuata) represented <2% of odontocete sightings, and sighting rates varied by depth and among islands. Photo-identification shows that 318 of 443 identified individuals are linked by association in the main component of the socialnetwork. Movements among islands were limited, with individuals off O‘ahu and Hawai‘i exhibiting high site fidelity, although resident groups from each island share a common mitochondrial haplotype. Three groups involved in mass strandings in two different years were not linked to the main component of the social network, and did not share mitochondrial haplotypes with known resident groups.  Conclusions. The approach of prioritizing rarely-encountered species for additional sampling is an effective way of learning more about poorly-known species. Implications. Such an approach may be critical for filling data gaps for populations potentially at risk from human activities.

Ka Hōʻuluʻulu:

Ka Pōʻaiapili. ʻAʻole paha e kākoʻo nākeʻena kālā i ka noi ʻina i nā lāhulu e ʻike kākaʻikahi ʻia a ʻaʻole hoʻi nui nā hola e lilo ana i ka launa ʻana me ia mau lāhulu inā hoʻi ʻaʻole nō lākou ke kia ʻi ʻē aʻe, a pēla pū i nā hāpana ōewe o nā holoholona ili me nā kānaka noiʻi ʻē aʻe. Kālailai ʻia ka hopena o nā hāpana ōewe me nā wehewehena ʻikepili lepili i loko ka pōʻaiapili o ka hoʻonoho launa a me nā moʻokūʻauhau ʻike hou ʻana. Nā hua nui. Mai loko mai o nā ʻikena i nā koholā niho, ʻike ʻia nā koholā luku ʻiʻi (Feresa attenuata) he ʻuʻuku iho o ka ʻelua pākēneka, a kū ka pinepine o ka ʻike ʻia ʻana i ka hohonu a puni nā mokupuni. Hōʻike ʻia nā kiʻi, pili he 318 mai loko mai o ka 443 i ka ʻūmaupaʻa nui o ka hoʻonoho launa. ʻAʻole i nui ka holo ʻana i waena o nā mokupuni, hōʻike ʻia naʻe ke kū loa o nā mea ma kai aku o Oʻahu me Hawaiʻi i ka leo, like naʻe kekahi ōewe hoʻoilina i waena o nā pūʻulu noho o kēlā me kēia mokupuni. ʻAʻohe pilina oʻekolu pūʻulu i pili i nā nuʻa ili o ʻelua makahiki ʻokoʻa i ka ʻūmaupaʻa nui o ka hoʻonoho launa, a ʻaʻole hoʻi i kaʻana like ʻia kekahi mau ōewe hoʻoilina me nā pūʻulu noho ʻike mua ʻia. Nā hopena. He kiʻina hana kūpono ka hoʻomakakoho ʻana i nā lāhulu ʻike kākaʻikahi ʻia no ka hāpana hou ʻana i mea e mōakāka hou aku ai ka ʻike no nā lāhulu laha ʻole. Nā panina manaʻo. He mea koʻikoʻi nō pha kēia ʻano kiʻina hana no ka hoʻopihapiha ʻana aku i nā ʻikepili kōā no nā lāhulu pā paha i nā hana kānaka.

Citation:

Baird, R.W., S.D. Mahaffy, B. Hancock-Hanser, T. Cullins, K.L. West, M.A. Kratofil, D.M. Barrios, A.E. Harnish, and P.C. Johnson. 2024. Long-Term Strategies for Studying Rare Species: Results and Lessons from a Multi-Species Study of Odontocetes Around the Main Hawaiian Islands. Pacific Conservation Biology. In Press. doi: 10.1071/PC23027