title: Comparative population assessments of Nautilus sp. in the Philippines, Australia, Fiji, and American Samoa using baited remote underwater video systems.
abstract: The extant species of Nautilus and Allonautilus (Cephalopoda) inhabit fore-reef slope environments across a large geographic area of the tropical western Pacific and eastern Indian Oceans. While many aspects of their biology and behavior are now well-documented, uncertainties concerning their current populations and ecological role in the deeper, fore-reef slope environments remain. Given the historical to current day presence of nautilus fisheries at various locales across the Pacific and Indian Oceans, a comparative assessment of the current state of nautilus populations is critical to determine whether conservation measures are warranted. We used baited remote underwater video systems (BRUVS) to make quantitative photographic records as a means of estimating population abundance of Nautilus sp. at sites in the Philippine Islands, American Samoa, Fiji, and along an approximately 125 km transect on the fore reef slope of the Great Barrier Reef from east of Cairns to east of Lizard Island, Australia. Each site was selected based on its geography, historical abundance, and the presence (Philippines) or absence (other sites) of Nautilus fisheries The results from these observations indicate that there are significantly fewer nautiluses observable with this method in the Philippine Islands site. While there may be multiple possibilities for this difference, the most parsimonious is that the Philippine Islands population has been reduced due to fishing. When compared to historical trap records from the same site the data suggest there have been far more nautiluses at this site in the past. The BRUVS proved to be a valuable tool to measure Nautilus abundance in the deep sea (300-400 m) while reducing our overall footprint on the environment.
authors: Department of Biology, Graduate Center, City University of New York, New York, New York, United States of America; Department of Biology, Brooklyn College, City University of New York, Brooklyn, New York, United States of America.
authors: Gregory J
authors: GJ
authors: Barord
authors: Department of Biology, University of Washington, Seattle, Washington, United States of America.
authors: Frederick
authors: F
authors: Dooley
authors: School of Biomedical Sciences, University of Queensland, Brisbane St. Lucia, Queensland, Australia.
authors: Andrew
authors: A
authors: Dunstan
authors: Department of Biology, University of San Carlos, Cebu City, Cebu, Philippines.
authors: Anthony
authors: A
authors: Ilano
authors: Department of Biology, Alaskan Observers Incorporated, Seattle, Washington, United States of America.
authors: Karen N
authors: KN
authors: Keister
authors: Department of Psychology, Hunter College, City University of New York, New York, New York, United States of America.
authors: Heike
authors: H
authors: Neumeister
authors: Department of Psychology, Hunter College, City University of New York, New York, New York, United States of America.
authors: Thomas
authors: T
authors: Preuss
authors: Department of Biology, University of Washington, Seattle, Washington, United States of America; Department of Earth and Space Sciences, University of Washington, Seattle, Washington, United States of America.
authors: Shane
authors: S
authors: Schoepfer
authors: Department of Biology, University of Washington, Seattle, Washington, United States of America; Department of Earth and Space Sciences, University of Washington, Seattle, Washington, United States of America.
authors: Peter D
authors: PD
authors: Ward
mesh_terms: D018948:American Samoa; D000818:Animals; D001315:Australia; D057894:Coral Reefs; D005367:Fiji; D049850:Nautilus / Q000254:growth & development*; D010679:Philippines; D010781:Photography; D011157:Population Dynamics; D058998:Remote Sensing Technology / Q000379:methods*; D014741:Video Recording; D014867:Water
chemical_list: D014867:Water