MARMAM readers may be interested in this recent publication that, while focusing on white sharks, also reports on marine mammal occurrence in an oceanic region:
Domeier, M.L., N. Nasby-Lucas and D.M. Palacios. 2012. The Northeastern Pacific White Shark Shared Offshore Foraging Area (SOFA): A First Examination and Description from Ship Observations and Remote Sensing. Pages 147–158, Chapter 12, in: M.L. Domeier, Ed. Global Perspectives on the Biology and Life History of the White Shark, CRC Press, DOI: 10.1201/b11532-15. Abstract Previous studies have shown that adult White Sharks (*Carcharodon carcharias *) migrate from aggregation sites near the coast to pelagic habitats situated between North America and Hawaii. Studies using satellite-linked radio transmitting (SLRT) tags have allowed for a better spatial description of this region while also delineating sex-specific offshore habitat partitioning. Although females roam widely in the pelagic habitat, males occupy a more defined region called the Shared Offshore Foraging Area (SOFA). Here we report the first direct observations of the SOFA, made from a ship in June 2009, and compare these observations with oceanographic remote sensing data to characterize the SOFA habitat. White sharks tagged with SLRT tags provided real-time tracking positions to guide the research vessel toward offshore regions used by White Sharks. The timing of the expedition coincided with a seasonal contraction of the SOFA. Ship observations in the region where the sharks were detected revealed an absence of epipelagic fish and small cetaceans, but Sperm Whales (*Physeter macrocephalus*) and three species of spawning squid (*Architeuthis* and two species of Ommastrephid squids) were present. Oceanographic remote sensing data showed the region to be an epipelagic cold spot, broadly characterized by downwelling conditions, reduced horizontal motions or other dynamical processes, no major temperature fronts, and very low phytoplankton biomass. However, the presence of apex predators like White Sharks, Sperm Whales, and squid suggests that the SOFA ecosystem supports a considerable mesopelagic biomass. Oceanic hot spots are currently described primarily by epipelagic and surface observations; this study demonstrates the need to incorporate mesopelagic observations into the characterization of hot and cold spots. A PDF is available (10.7MB). -- *Daniel M. Palacios, Ph.D.* Joint Institute for Marine and Atmospheric Research, Univ. Hawaii & Environmental Research Division, NOAA/NMFS/SWFSC Pacific Fisheries Environmental Laboratory 1352 Lighthouse Ave. Pacific Grove, CA 93950-2097 USA Phone: 831-658-3203 Fax: 831-648-8440 Email: [email protected] http://www.pfeg.noaa.gov/~dpalacio http://scholar.google.com/citations?user=bBjy6ZcAAAAJ http://www.researcherid.com/rid/B-9180-2008 ------------------------------------------------------------------------------------ Disclaimer: The contents of this message are mine personally and do not necessarily reflect any position of the Government or the National Oceanic and Atmospheric Administration.
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