Deep Sea Acoustic and Optical Predator-Prey Observations
Abstract
Marine mammals, particularly beaked whales, are of concern to the US Navy regarding noise impacts during naval training exercises. T,o successfully quantify behavioral responses to noise and potential short- and long-term impacts, it is essential to understand indi,viduals and their behaviors under natural as well as disturbed circumstances. Behavioral responses caused by naval sound sources, es,pecially mid-frequency active sonar (MFAS), will likely be dependent upon the behavioral state of an individual. This behavioral sta,te in turn is often driven by the underlying environmental conditions that determine prey distributions.The pelagic environment whic,h marine mammals inhabit is a highly dynamic, mobile environment. Dynamic ecosystem-based management and impact mitigation requires,a holistic view of the pelagic ecosystem, with an understanding of the organismal, individual behavior of the top predator but also,deep knowledge of the composition and behavior of prey communities as well as underlying physics of the pelagic. Due to the elusive,nature of marine mammal prey and their remote, deep-sea habitat, knowledge on their presence, abundance, behavior, and distribution,is extremely limited. Enhancement of our understanding requires the application of a suite of state-of-the-art technology. Here we,propose to improve the instrumentation for deep sea acoustic and optical predator-prey observations. It is intended to procure compo,nents to assemble one passive-active acoustic tracking mooring, four autonomous deep sea camera systems and four animal-borne camera, tags.The proposed instrumentation is designed to gather detailed insights into predator-prey dynamics and associated oceanography i,n the deep sea, with a focus on beaked whales. This is done through combined passive acoustic tracking and visual recording of prey,, in their habitat as well as from the direct perspective of the predator. The passive-active acoustic tracking (PAAT) mooring is des,igned to determine deep-sea prey abundance and distribution, how these are influenced by oceanographic conditions, and how these con,sequently influence predator foraging behavior and habitat use. However, with this instrumentation we lack more complex identificati,on of prey species, their size classes and precise behavioral interactions of predator and prey. Data collection will therefore be e,xtended with concurrent recording by autonomous deep sea camera systems and animal-borne camera tags. With this holistic suite of se,nsors, we can begin to incorporate ecosystem-based management practices to mitigate noise impacts on marine mammals, specifically be,aked whales, caused by US Navy training operations.This project summary is publicly releasable.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 05, 2022
- Source ID
- N000142212243
Entities
People
- Simone Baumann-Pickering
Organizations
- Office of Naval Research
- United States Navy
- University of California, San Diego