Research

The Effects of Wind Speed and Direction on Both Sea Surface Temperature and Strandings of Harbor Porpoise

Dr. Aleta Hohn
NOAA Beaufort Laboratory
101 Pivers Island Road
Beaufort, NC 29815
Tel: 252-728 8797 or 8732

Interns for the summer of 2004 will assist with determining whether an unusually high number of strandings of harbor porpoise during the winter of 1999 was due to an unusual juxtaposition of oceanographic features in the western the mid-Atlantic. The goals are to investigate whether a narrow band of cold water near shore followed by a strong warm water front results in higher numbers of stranded harbor porpoise than when the front is further offshore. Further, interns will examine the effects of wind speed and direction on both sea surface temperature and strandings. Positive results may allow for development of a model that predicts relative numbers of harbor porpoise strandings. This question has been a concern because an alternative explanation for unusually high numbers of strandings is entanglement of porpoises in gillnets along the mid-Atlantic coast. The interns will work on compiling extracted sea surface temperature (SST) and wind data, creating graphs and GIS plots, and assisting with analysis of the data. Only one other episode of alarming numbers of strandings of harbor porpoise in North Carolina has occurred in recent times and that was in 1977. Interns will use SST and wind data for years when it was available to ensure that the convergence of oceanographic events seen in 1999 did not occur in other years when high numbers of strandings also did not occur. Although comparable data do not exist for the 1970’s, oceanographic sampling cruises did collect data that may be useful. Access to these results will require a literature search.

Required skills:

Interns should have a background in the natural sciences (biology, geology, oceanography) and statistics, with knowledge of Geographic Information System (GIS). An interest in applying remotely-sensed data to studies of marine mammal strandings in also valuable. In addition, the interns will have the opportunity to participate in field activities including small boat surveys for bottlenose dolphins and stranding responses. A strong background in computers with experience using GIS is preferred, but not essential. All necessary training to complete the tasks will be available for the duration of the internship. Interns should be familiar with remotely sensed data including sea surface temperature and wind. Familiarity with statistical and numerical software packages such as MatLab, SAS, and SYSTAT would be beneficial.