Department of Oceanography
Naval Postgraduate School
Monterey, CA 93943-5000

January 7, 2008

Oceanography Seminar

SPEAKER:

Jay Barlow

AFFILIATION:

NOAA Southwest Fisheries Science Center, La Jolla, CA

TITLE:

NOAA west-coast cetacean surveys: advancements in understanding the role of cetaceans in the California Current Ecosystem

DATE:

Friday, January 11, 2008

TIME:

2:00 PM

PLACE:

Spanagel 316

ABSTRACT

The SWFSC has been conducting cetacean surveys along the US West Coast for over 25 years. These surveys cover waters from the coast to 300 nmi offshore and have evolved to include a broad range of oceanographic and ecosystem measurements. The primary motivation of the surveys is to estimate the abundance of cetacean species and to monitor trends in their abundance. I describe the past surveys and present estimates of cetacean abundance from surveys in 1991-2005. These abundance estimates are used to estimate the biomass and food consumption of cetaceans in the California Current Ecosystem. To better understand the role played by cetaceans as top-level predators in the California Current ecosystem, I estimate the fraction of annual net primary production (NPP) required to support cetaceans using a simple trophic transfer model. Assuming a 10% trophic transfer efficiency, cetaceans are estimated to require approximately 12% of the NPP in the California Current to sustain the prey that they directly consume. Whales in the California current are still recovering from whaling, and their prey and primary production requirements are expected to increase over the next decade. A new cetacean survey of 150 sea days is planned for the summer and fall of 2008, and I will talk about our plans for that survey and for the ecosystem sampling that will occur on that survey.

NOTE: Gate access requires 48 hour notice. Please notify Katherine (656-2757) or Susan (656-2553) if you need to be placed on the gate access list. For more information about the NPS Oceanography Department Seminar Series, see http://www.oc.nps.navy.mil/seminars.