Vessel Monitoring and Right Whales
Vessel strikes are the leading cause of mortalities for N.A. right whales and the southeast U.S. (SEUS) calving ground is where this species is the most vulnerable. In a study, researchers of the Marine GIS Group assessed vessel operator compliance to mandatory speeds and recommended routes that were implemented to protect the N.A. right whale from vessel collisions. Researchers used the Automatic Identification System (AIS) to collect data on large ocean going vessels during the aerial surveys for the duration of the calving season in the SEUS from 1995-2009.
AIS is an automated vessel tracking system which supplements marine radar to identify the location and identity of surrounding vessels for maritime safety1. Vessels transmit and receive AIS signals, each transmission includes information on the location of the vessel, speed, direction, name, destination, type, and size. Vessels transmit signals every 2-8 seconds, so the researchers were able characterize the behavior and use patterns of the vessels with high spatial and temporal resolution.
The study found vessels only complied to speed restrictions when mandatory speed restrictions were in place compared to recommended speed restrictions. However, vessels seemed to comply with recommended routes reducing the potential overlap between high use areas and vessels. The mandatory ship restrictions and recommended routes in combination show the most conservation impact, having the potential to reduce the annual mortality rate by 72% in this important habitat.
For more information see: Lagueux K.M., M.A. Zani, .A.R. Knowlton, S.D. Kraus. 2011. Response by vessel operators to protection measures for right whales Eubalaena glacialis in the southeast US calving ground. Endangered Species Research.