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  • Using DTAGs to study vessel sound exposure & effects on behavior in southern resident killer whales


Northwest Fisheries Science Center (NWFSC) Conservation Biology CB - Ecosystem Science


Using DTAGs to study vessel sound exposure & effects on behavior in southern resident killer whales
Drs. Marla Holt, Brad Hanson, and Candice Emmons of the NWFSC, along with collaborators from Cascadia Research Collective and UC Davis, are currently conducting a study using digital acoustic recording tags (DTAGs) to examine sound exposure, sound use, and behavior of Southern Resident killer whales (SRKWs) in core summer habitat. The DTAG is suction cup attached and consists of a number of different sensors that record sound, pitch, roll, heading, and depth. The tag was developed by Woods Hole Oceanographic Institution specifically to monitor the behavior of marine mammals and their response to sound, continuously throughout the dive cycle. Prey samples and vessel data are also concurrently collected relative to tagged whales in a manner similar to previous work. The project research goals include the following:

(1) Measure noise levels in biological relevant frequency ranges that are received by individual SRKWs.

(2) Quantify the relationship between vessels and received noise levels.

(3) Determine acoustic behavior during different activities and matched with fine scale details on movement, especially those indicative of foraging.

(4) Quantify foraging efforts and determine potential effects of vessels and associated noise levels.

The results of this study will provide pertinent data to address multiple risk factors of SRKWs including vessel disturbance, noise exposure, effects on foraging, and cumulative effects. The specific work that will be done includes experimental design, data collection, data analysis, and writing for submission to peer-reviewed journals.

Research Themes

Recovery and rebuilding of marine and coastal species
The Pacific Northwest is home to several iconic endangered species, including Pacific salmon and killer whales, and several rockfish species. Mandates such as the Endangered Species Act, MagnusonStevens Act, and the Marine Mammal Protection Act, grant NOAA Fisheries the authority to manage the recovery of depleted species and stocks. The NWFSC contributes to species recovery through research, monitoring and analysis, providing NOAA managers and regional stakeholders the tools and information they need to craft effective regulations and develop sustainable plans for recovery.

Research Foci

Describe the relationships between human activities and species recovery, rebuilding and sustainability
Human activities play a major role in determining the status of species and stocks. Rebuilding and recovery therefore need to address how these activities affect their status. At the NWFSC, biophysical modeling is used to link specific human activities such as land use and pollution to habitat conditions, and then to link these conditions and other activities to particular life stages. These models can be used to quantitatively assess how human activities influence species abundance, productivity, distribution and diversity. Not surprisingly, altering human activities in some way is often necessary for species or stock recovery and rebuilding. It is therefore important to understand the socio-economic effects of alternative management structures. Gathering data on their economic costs and social impacts helps identify actions that are cost-effective. These actions will need to be resilient to potential changes in climate throughout the region. Research on how humans react to management strategies helps policy makers avoid those that lead to unintended consequences that can hinder rather than help recovery.


digital acoustic recording tag
behavioral effects of noise
killer whale
focal species
vessel sound exposure
specific anthropogenic effect


None associated


Species Orcinus orca
grampus, killer whale, killer-trasher, orca


Brad Hanson
Candice Emmons
Internal Collaborator
Marla Holt
Principal Investigator