Documenting Whale Migration off Virginia's Coast
Virginia is poised to become a leader in offshore wind energy development. Although wind can provide clean renewable energy, the development of a wind farm is likely to impact the animals that live in our offshore waters. Aquatic species most likely impacted by wind turbine construction will be marine mammals, especially large whales, many of which are endangered. In order to plan for renewable energy development that creates the least impact on Virginia's marine mammal species, the Aquarium has teamed up with the University of North Carolina Wilmington to conduct aerial surveys of Virginia's Wind Energy Area (WEA). Knowing what protected species occur in and around the WEA is essential for environmentally responsible offshore wind energy development.
A twin engine aircraft that carries two pilots and two observers conduct these aerial surveys. Thus far during the fall, winter, and spring of 2012 and 2013, we have conducted a small number of surveys. We have sighted humpback, fin, and minke whales as well as several species of dolphin and numerous sea turtles. Data collected from aerial surveys will be included in ocean mapping tools that are being developed to assist in the siting of offshore energy projects – a process called marine spatial planning.
This project is supported by the National Oceanic and Atmospheric Administration (NOAA) funding and a grant from the Virginia Coastal Zone Management Program. We have funds to continue aerial survey efforts in 2014 and hope to be able to conduct surveys in all months of the year.
Discovering Life History from Stranded Bottlenose Dolphins
Coastal bottlenose dolphins are the most commonly observed marine mammal in Virginia, are seasonally present, and can be observed consistently from April through October of each year. They are also the most commonly stranded marine mammal with an average of 64 strandings per year during the last ten years (2003-2012). Little has been known about the life history and overall ecology of these dolphins from the mid-Atlantic region until now.
The Aquarium Stranding Team conducts necropsy (animal autopsy) examinations on stranded dolphins, resulting in a vast archive of data and samples such as teeth, gonads, and stomachs. In 2009, the Aquarium initiated a three-year project to conduct analyses of archived teeth (to determine age) and gonads (to investigate reproductive status) from stranded bottlenose dolphins. We examined teeth from more than 300 dolphins and found they ranged in age from 0-48 years. The oldest male was 35 and the oldest female was 48. Examination of the gonads provided data on the sexual maturity of the animals.
Beginning in 2012, we analyzed the stomach contents from archived samples. This project primarily investigates the dietary preferences of bottlenose dolphins and will complete the analyses of our archived life history samples. The data will be applied to characterize diet and investigate feeding habits and understand the occurrence of domoic acid and other biotoxins in dolphin prey. These projects represent the first comprehensive life history studies focusing exclusively on bottlenose dolphins in Virginia.
These life history studies have been funded by two grants from the NOAA John H. Prescott Marine Mammal Stranding Response Grant Program.