Marine Mammals and Birds

Whales and seabirds utilize oceanic plankton and nekton as food and may congregate in productive frontal zones and around topographic features. Researchers plan to conduct visual surveys of the large-scale migration patterns of whales and seabirds during the MAR-ECO cruises.

Aims

1. Map cetacean and seabird species composition and their temporal and spatial distribution at varying scales.
2. Establish knowledge of scale-dependent habitat use.
3. Establish knowledge of behavioural interactions among and between cetaceans, seabirds and their prey at different spatial scales.
4. Develop and test models of the relevance and importance of hydrographical and topographical features, associated prey distribution and frontal processes for the formation of seabird and cetacean habitats.
5. Test the application of marine mammals and seabirds as indicators of key food webs and areas of aggregations of pelagic prey.

Hypothesis

Compared to shelf environments the migration and distribution of birds and
mammals in the open ocean is less patchy. These top predators are influenced at
relatively large (meso) scale, by topographic and hydrographic features such as
the MAR or the Sub-polar front and the concentrations of prey associated with
these features.

Strategy

Acoustic corridor and visual transect sampling in the three MAR-ECO
Sub-areas, and also lander observations and submersible observations.

Technology (methods)

• Visual census.
• Towed and bottom-mounted hydrophones for recording sounds from
  mammals.
• Satellite tags for large cetaceans.
• Instruments to collect data on hydrography, circulation and potential prey abundance and distribution. Please see MAR-ECO components Z1, PN1, and DN1.
• GIS-based statistics and modelling. (EasyGIS).

Schedule

Preparation of fieldwork: 2002-2003, Sampling and observation at sea: 2003-2005, Analysis, modelling and dissemination: 2005-2008.

Partners

Principal Invetigators: Leif Nøttestad (Norway), Henrik Skov (Denmark)

Gisli Vikingson (Iceland), Monica Silva (Portugal), Erik Olsen, Arne Bjoerge, Bjoern Erik Axelsen (Norway), Jim Reid, Mark Tasker, Rus Hoelzel (UK), Gordon Waring, Tim Smith, Mike Vecchione (USA).