Distribution and Accumulation of Marine Debris: Implications for Cetaceans

Project Name:

Distribution and Accumulation of Marine Debris: Implications for Cetaceans

Study System:

Marine debris and odontocetes of Maui

Motivation and Goals:

Marine debris or trash is one of the biggest environmental threats since much of the debris is comprised of plastics and other materials that resist natural degradation.  This results in adverse effects to marine organisms via ingestion and entanglement. 

This research project aims to determine where concentrations of marine debris may exist in Maui waters. The marine debris research is also integrated with our odontocete research and will allow us to determine if any areas of debris concentration overlap with the distribution of odontocetes.  Simultaneously studying marine debris and odontocete distribution enables us to directly quantify potential impacts of debris on marine mammals. 

Methods:

Using line transect surveys, we search for floating marine debris.  When marine debris is sighted, we record its location before removing the debris to reduce potential entanglement or ingestion instances for marine mammals.  After debris has been removed, we inspect it for any features that may link the debris with recent tsunami events and report any such debris to the Department of Land and Natural Resources to contribute to their Japan tsunami debris database. 

Results To Date:

Analysis of the composition and location of marine debris around Maui suggests that there is a steady flow of debris throughout the four-island region. The majority of debris is comprised of plastics, and higher concentrations occur if oceanic currents are stalled for long periods of time. 

Next Steps:

To better understand the potential threat that marine debris poses to marine mammals, we will incorporate data from our odontocete research to examine any areas of overlap between concentrations of marine debris and the odontocete species of Maui.