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Poster Abstract Title: 
Endeavour Integrated Studies Site: Distribution of fin whales above hydrothermal vent fields
Authors and their affiliations: 
Soule, D., University of Washington

From 2003-2006, we deployed an eight-station seafloor seismic network along a 10-km portion of the Endeavour segment of the Juan de Fuca ridge. In addition to microearthquakes, the network recorded an extensive data set of 20-Hz fin and blue whale calls. During the first year of operation we have identified more than 100,000 fin calls. The call rates vary seasonally with highest rates from November through January and very few calls from May to August (Soule et al.,2009). Previous work at this site has detected enhanced concentrations of zooplankton throughout the water column above the hydrothermal vent fields compared to sites ≥10 km away (Burd and Thomson 1995). As part of the project to investigate the hypothesis that whales are preferentially found above the hydrothermal vent fields, we have developed an algorithm to detect and track vocalizing whales that swim near the seismic network. The tracking algorithm can successfully track whales up to 10-15 km from the seismic network with little human intervention. The statistical analysis is focused on understanding the calling patterns and how these could be correlated with known diving patterns that have been linked to feeding (Croll, Acevedo-Gutierrez et al. 2001). For each track we measure the spatial length, total elapsed time, estimated velocity, the distribution of call intervals, and the distribution of call frequencies. My poster will present the detection results from all three years of data, as well as the whale tracks and initial statistical analysis of the call patterns from the first year of data.

Burd, B. J. and R. E. Thomson (1995). "DISTRIBUTION OF ZOOPLANKTON ASSOCIATED WITH THE ENDEAVOR RIDGE HYDROTHERMAL PLUME." Journal of Plankton Research 17(5): 965-997.

Croll, D. A., A. Acevedo-Gutierrez, et al. (2001). "The diving behavior of blue and fin whales: is dive duration shorter than expected based on oxygen stores?" Comparative Biochemistry and Physiology a-Molecular & Integrative Physiology 129(4): 797-809.

Soule, Dax C., Wilcock, William S. D., Thompson, R. E. (2009) " Distribution of fin and blue whales above hydrothermal vent fields on the Juan de Fuca Ridge, N. E. Pacific Ocean" Society for Marine Mammology Poster.

Contributions to Integration and Synthesis: 
As summarized in E&O WG forum: Mantle to Mammal - White Paper: Endeavour Integrated Studies Site: Distribution of fin whales above hydrothermal vent fields. Extending ridge studies beyond “mantle to microbe” to encompass “mantle to mammal.” Soule describes ongoing work to test the hypothesis that whales are preferentially found above the hydrothermal vent fields. Results of this work could confirm a trophic link between the mantle and the rest of the food chain. “Establishing this link would connect a food chain that encompasses the oldest and smallest microbes on the planet with some of the largest animals to have ever lived.”