Our lab is part of a consortium of academic institutions that is implementing a large-scale monitoring program to provide the U.S. Navy with baseline data on the occurrence, density and residency patterns of marine mammals, seabirds and sea turtles at three reference sites in the Atlantic Fleet Active Sonar Training area.  We are conducting year-round field work off Cape Hatteras and Onslow Bay, North Carolina and Jacksonville, Florida.  The Consortium includes Duke University, the University of North Carolina at Wilmington, the Scripps Institution of Oceanography and the University of St. Andrews. Our monitoring program includes line transect vessel and aerial surveys, photo-identification, biopsy sampling, behavioral observations and passive acoustic monitoring using towed arrays and High Frequency Acoustic Recording Packages.  This program is yielding a rich picture of the distribution and ecology of marine megafauna in these three areas.  This project is supported by Naval Facilities Engineering Command Atlantic.

The objective of this study is to determine the degree of overlap in distribution of two stocks of bottlenose dolphins off the North Carolina coast during the summer months.  The Northern North Carolina Estuarine stock is distributed primarily within Pamlico Sound, but occasionally extends into coastal waters.  The Southern Migratory Coastal stock is only found in coastal waters (as its name implies).  Dolphins from both stocks are at risk of entanglement in near-shore gill net fisheries; this project is designed to determine which of the two forms is most as risk of entanglement in near-shore nets.  We are employing photo-identification, biopsy sampling and analysis of stable isotopes to determine the distribution of the two stocks.  This work is supported by the National Oceanic and Atmospheric Administration.

We are monitoring the distribution and abundance of marine mammals (primarily bottlenose and spotted dolphins) in Camp Lejeune, Notth Carolina.  The U.S. Marine Corps conducts a variety of training exercises in Camp Lejeune and we are providing them with baseline information on marine mammals in these estuarine and coastal habitats.  Our regular visual surveys and photo-identification work is limited by weather, daylight, and training exercises. Thus a more comprehensive picture can be provided by complementing these surveys with passive acoustic monitoring systems. We currently use archival click detectors (CPODs) to monitor dolphin use of the New River estuary system to provide information on daily and seasonal patterns of bottlenose dolphin use of these area.  This work is supported by the U.S. Marine Corps.

We are conducting a long-term study of short-finned pilot whales off Cape Hatteras, North Carolina.  We employ a variety of methods, including photo-identification, biopsy sampling, fisheries oceanography and the application of Digital Acoustic Tags (DTags) to study the behavior and ecology of these animals.  We are particularly interested in their foraging behavior and interactions with the pelagic longline fishery in this area; some whales have learned to remove captured tuna – a behavior termed depredation – which leads to an economic cost to the fishery and a risk of entanglement to the whales.  This research is conducted with colleagues at the Woods Hole Oceanographic Institution and is supported by the National Oceanic and Atmospheric Administration, Naval Facilities Engineering Command Atlantic, North Carolina Sea Grant Fishery Resource Grant Program and the Consortium for Wildlife Bycatch Reduction.

The objective of this project is to understand how odontocete cetaceans respond to the sounds of potential predators, which share some characteristics with the sounds of some military mid-frequenncy active sonars. We will use DTags to examine the responses of several species with different social patterns, from solitary species to those that live in permanent family groups, to determine whether social structure influences the response to acoustic stimuli.  Our field work will be conducted off Cape Hatteras, North Carolina and Kona, Hawaii.  We will use these observations will be used to create a conceptual model of the anti-predator behavior of odontocete cetaceans to improve understanding of their response to certain anthropogenic sounds.  This project is funded by the Strategic Environmental Research and Development Program.

Damon Gannon’s Ph.D. thesis (Gannon 2003) described patterns of habitat use for bottlenose dolphins in the Neuse River estuary. The prey of dolphins is distributed evenly throughout the estuary, but dolphins are found almost exclusively along the shallow margins of the estuary. Therefore, bottlenose dolphin habitat use cannot be predicted solely by the distribution of their prey. Damon hypothesized that predation risk could be structuring the habitat use of estuarine dolphins. Bull sharks are euryhaline predators that inhabit both estuarine and coastal ecosystems. As top predators, they have the potential to directly and indirectly influence the distribution and abundance of their prey species, such as bottlenose dolphins. Approximately 34% of bottlenose dolphins in North Carolina have scars from predation attempts by sharks. We are using fishing and acoustic tracking to evaluate the habitat use of bull sharks in the Neuse River estuary. Understanding the movement patterns and habitat use of bull sharks will allow us to examine the influence of this predator on the habitat use of bottlenose dolphins. This project is funded by the Joseph F. Ramus Endowment Fund.