White Sharks (NW Atlantic)
Massachusetts, USA
Key Objective:
The objective of the current study is to use passive acoustic telemetry to examine fine-scale movements, habitat use, site fidelity, and feeding behavior of white sharks in the western North Atlantic.
Why this is important:
Although the occurrence of white sharks is well documented in the North Atlantic, the species is relatively rare and much of what is known about its distribution and movements is limited to historical sightings data. With growing evidence that white shark populations are overexploited worldwide, studies to examine the life history and ecology of this species are warranted for conservation and protection.
Background
The seasonal (summer, early fall) presence of great white sharks off the coast of Massachusetts has been well documented. However, based on historical sightings data, the species is known to be relatively rare in the Atlantic. Data compiled by the MA Shark Research Project show that the number of white shark sightings has been rising in recent years off the coast of Massachusetts. There has also been a concurrent increase in the number of white shark attacks on seals, largely adjacent to Monomoy Island off the coast of Cape Cod, which hosts a sizeable growing population of gray seals. White sharks, which were thought to generally feed offshore in the Atlantic, appear to be exhibiting a dietary shift in response to changes in seal abundance. As a result, it is anticipated that the number of white shark sightings as well as seal attacks will continue to rise off the coast of Massachusetts. The advent of new tagging technologies has allowed researchers to examine the movements, habitat use, and behavior of white sharks in the Pacific and Indian Oceans, but, until recently, the elusive nature of this species in the Atlantic has been a roadblock to such studies in this region. However, the relative increase in white sharks off the coast of cape Cod has allowed us to tag 13 individuals during the summers of 2009 and 2010 with pop-up satellite archival transmitting tags or acoustic transmitters. Given the high profile nature of the white shark, these tagging efforts garnered considerable media attention. This was also the first successful effort to apply these tags to white sharks in the North Atlantic Ocean. The proposed study will augment these initial tagging efforts.
Aims and Objectives
The general aim of the proposed work is to study the ecology of the white shark in a part of the world where it remains largely unknown. The objective of the study is to examine fine- and broad-scale movements, habitat use, site fidelity, residency, and feeding behavior of white sharks in southern New England and along the east coast of the US.
Project leader:
Greg Skomal
Partners:
MA Marine Fisheries
Related threat:
Years funded:
2011