title: Passive acoustic monitoring of beaked whale densities in the Gulf of Mexico.
abstract: Beaked whales are deep diving elusive animals, difficult to census with conventional visual surveys. Methods are presented for the density estimation of beaked whales, using passive acoustic monitoring data collected at sites in the Gulf of Mexico (GOM) from the period during and following the Deepwater Horizon oil spill (2010-2013). Beaked whale species detected include: Gervais' (Mesoplodon europaeus), Cuvier's (Ziphius cavirostris), Blainville's (Mesoplodon densirostris) and an unknown species of Mesoplodon sp. (designated as Beaked Whale Gulf - BWG). For Gervais' and Cuvier's beaked whales, we estimated weekly animal density using two methods, one based on the number of echolocation clicks, and another based on the detection of animal groups during 5 min time-bins. Density estimates derived from these two methods were in good general agreement. At two sites in the western GOM, Gervais' beaked whales were present throughout the monitoring period, but Cuvier's beaked whales were present only seasonally, with periods of low density during the summer and higher density in the winter. At an eastern GOM site, both Gervais' and Cuvier's beaked whales had a high density throughout the monitoring period.
authors.affiliation: Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0205, USA.
authors.forename: John A
authors.initials: JA
authors.lastname: Hildebrand
authors.affiliation: Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0205, USA.
authors.forename: Simone
authors.initials: S
authors.lastname: Baumann-Pickering
authors.affiliation: Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0205, USA.
authors.forename: Kaitlin E
authors.initials: KE
authors.lastname: Frasier
authors.affiliation: Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0205, USA.
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Trickey
authors.affiliation: Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0205, USA.
authors.forename: Karlina P
authors.initials: KP
authors.lastname: Merkens
authors.affiliation: Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0205, USA.
authors.forename: Sean M
authors.initials: SM
authors.lastname: Wiggins
authors.affiliation: WhaleAcoustics, 11430 Rist Canyon Road, Bellvue, Colorado 80512, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: McDonald
authors.affiliation: National Marine Fisheries Service, Southeast Fisheries Science Center, 75 Virginia Beach Dr. Miami, Florida 33149, USA.
authors.forename: Lance P
authors.initials: LP
authors.lastname: Garrison
authors.affiliation: Centre for Research into Ecological and Environmental Modelling, The Observatory, University of St Andrews, St Andrews, KY16 9LZ, Scotland.
authors.forename: Danielle
authors.initials: D
authors.lastname: Harris
authors.affiliation: Centre for Research into Ecological and Environmental Modelling, The Observatory, University of St Andrews, St Andrews, KY16 9LZ, Scotland.
authors.forename: Tiago A
authors.initials: TA
authors.lastname: Marques
authors.affiliation: Centre for Research into Ecological and Environmental Modelling, The Observatory, University of St Andrews, St Andrews, KY16 9LZ, Scotland.
authors.forename: Len
authors.initials: L
authors.lastname: Thomas
mesh_terms: D000162:Acoustics; D000818:Animals; D004455:Echolocation; D005843:Geography; D060851:Gulf of America; D011156:Population Density; D013018:Sound Spectrography; D014828:Vocalization, Animal; D014907:Whales