Resource drivers of the behavior of teuthivorous whales
Abstract
Deep-diving, teuthivorous whales appear to be particularly sensitive to operational military sonars and other anthropogenic sound sources. Population-based models have revealed that estimates of the consequences of non-lethal disturbances are strongly affected bythe distribution and abundance of prey. Estimating the distribution of highly mobile prey over the 500- to >1000-meter depth rangesover which these toothed whales dive, however, has proven a difficult task. As a result, the foraging ecology of squid-eating toothed whales including sperm whales, beaked whales, and Risso#s dolphins remains relatively poorly described. In order to quantify the consequences of disturbance for effective compliance and mitigation efforts, a comprehensive understanding of the relationship between whales and their habitat must be developed. This project seeks to apply and advance the integration of advanced, synoptic multi-sensor tools to measure the physical and ecological factors that drive foraging behavior of deep-diving cetaceans. We have developeda predator guided approach whereby real-time information on the location and behavior of focal species can provide adaptive sampling strategies using a suite of environmental sensors to sample areas that are both selectively targeted and less utilized by feeding focal species. This approach is strategically proposed for the Monterey Bay region to leverage substantial existing environmental measurement systems and rich ongoing datasets to quantify resource drivers of movement and diving behavior of top predators. We propose a phased, two-year pilot approach to test and evaluate the integration of methods in a locally-opportunistic field context with low-cost access to a robust set of environmental measurement sensors and an adaptive telemetry approach with different sensor configurations and settings. Results will provide not only novel, fine-scale synoptic measurements of diving and horizontal behavior of key cetacean species over weeks and months within well-characterized conditions, but also a means of informing how best to optimize and transfer such approaches to other regions where fewer remote sensing tools are currently in place. The goals of this work are: 1) Describe how sympatric teuthivorous (squid-eating) predators partition dynamic, three-dimensional habitats2) Explore differences in the foraging tactics of teuthivours predators that may result in differences in their susceptibility to and relative impacts from human disturbances3) Identify the minimum critical measurement suite for addressing questions about deep-diving predators and their preythat would allow these questions to be addressed in other ecosystems, including those that are a high priority for the NavyFuture Navy relevanceThe proposed work will advance integrated technology approaches to quantifying ecological drivers of behavior in federally-protected marine mammal species. Such knowledge is essential in understanding factors that influence basic behavior as well as how ecological context influences whether and how disturbances from military sonar and other active U.S. Navy noise sources will influence behavior. These data will amplify and complement ongoing Navy-funded research and monitoring using some of the sampling methods applied here. This work seeks to determine what tools are critical in making assessment decisions through all areas of interest for the Navy. Ultimately, these results will inform and improve impact assessments and compliance with Navy monitoring and mitigation requirements.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Nov 08, 2024
- Source ID
- N000142412457
Entities
People
- Kelly Benoit-Bird
Organizations
- Monterey Bay Aquarium Research Institute
- Office of Naval Research
- United States Navy