Inter-Research >  > Prepress Abstract

MEPS prepress abstract   -  DOI: https://doi.org/10.3354/meps13219

A decade of monitoring Atlantic cod (Gadus morhua) spawning aggregations in Massachusetts Bay using passive acoustics

Paul E. Caiger*, Micah J. Dean, Annamaria I. DeAngelis, Leila T. Hatch, Aaron N. Rice, Jenni A. Stanley, Chris Tholke, Douglas R. Zemeckis, Sofie M. Van Parijs

*Corresponding author:

ABSTRACT: Atlantic cod (Gadus morhua L.) populations in the northeast U.S. have failed to recover since major declines in the 1970’s and 1990’s. To rebuild these stocks, managers need reliable information on spawning dynamics to design and implement control measures. Discovering cost-effective and non-invasive monitoring techniques is also favorable. Atlantic cod form dense, site-fidelic spawning aggregations, during which they vocalize, permitting acoustic detection of their presence at such times. The objective of this study was to use multiple fixed station passive acoustic recorders to sample across Massachusetts Bay during the winter spawning period of Atlantic cod for the detection of spawning activity. A generalized linear modeling approach was used to investigate spatio-temporal trends of cod vocalizing over ten consecutive winter spawning seasons (2007-2016), the longest such timeline of any passive acoustic monitoring of a fish species. The vocal activity of Atlantic cod was associated with diel, lunar, and seasonal cycles, with a higher probability of occurrence at night, during the full moon, and near the end of November. Following 2009 and 2010, there was a general decline in acoustic activity. Furthermore, the northwest corner of Stellwagen Bank was identified as an important spawning location. This project demonstrated the utility of passive acoustic monitoring in determining the presence of an acoustically active fish species, and provides valuable data for informing the management of this commercially, culturally and ecologically important species.