Introduction & Objectives

Prior to this project, no surveys had been completed for marine mammals in the Mariana Archipelago.  The objective for this study was to determine what species of marine mammals and sea turtles are present in the Marianas and estimate abundance. 

Technical Approach

A systematic line transect survey was completed along the Mariana Archipelago.  Data collected included visual sightings data, photos, and towed array acoustics.  

Progress & Results

The survey was conducted January-April 2007 and covered over 11,033 km of tracklines.  There were 153 sightings of 13 species.  This survey produced the first density estimates for 12 marine mammal species in the Mariana Archipelago.  The density estimates were used in effects models and consultations between the Navy and NOAA for the Navy’s Mariana Islands Training and Testing environmental impact statement and associated regulations. 

Publications 

Distribution and Abundance Estimates for Cetaceans in the Waters of Guam and the Commonwealth of the Northern Mariana Islands

Estimation of minke whale abundance from an acoustic line transect survey of the Mariana Islands