Project Information

Title: Sea Otter Demographics and Habitat 93043-2

Project Year and Number: 1993: 93043-2

Other Fiscal Years and Numbers for this Project: 1993: 93043

Principal Investigator (PI): Jim Bodkin (US Geological Survey)

Managing Agency: USGS

Assisting Personnel: Mark Udevitz

Research Location: Prince William Sound

Restoration Category: Monitoring

Injured Resources Addressed: Sea Otters

Abstract: Immediate sea otter losses associated with the EVOS probably ranged from 3,000 to 5,000 animals. Sampling of sediments and sea otter prey items indicates that the exposure of otters to petroleum hydrocarbons may be continuing, affecting the survival and therefore the recovery of the population. As a continuation of work conducted in 1991 and 1992, this project will conduct population surveys of sea otters in the Prince William Sound using aerial surveying. Due to the identification of bias resulting in the boat surveys, aerial survey method began to be developed in 1991. A Global Positioning System (GPS) was used in the aircraft to locate the endpoints of each transect. Concentric circles within the width of the survey transect were flown, and data was collected. Continued survey development includes the investigation of two methods for increasing the sample size of intensive search units. Prince William Sound will be partitioned into 400 km-wide strip transects divided into 2 strata, feeding and non-feeding habitat. Data collected using aerial survey will be entered into a database. Mortality patterns will be evaluated through the recovery of sea otter carcasses surveyed on beaches in Prince William Sound. A Leslie matrix model for males and females will be constructed to model the sea otter population to predict recovery. Habitat use patterns will be analyzed.


Proposal: Not Available

Reports:
Final Report: View (1,563 KB)

Publications from this Project: None Available

Datasets:
EVOSTC Data Archive: 1) Aerial Survey Data - Prince William Sound wide survey of sea otter abundance, (point attribute data for transects). 2) Carcass collection data - Green Island, April 1993. 3) Carcass collection data - Western PWS, April - August 1989, (location, age, sex if known). ARCInfo, SAS, ASCII (Aerial Surveys). R-BASE, SAS, ASCII (Carcass Data). Availability: Could be made available, contact custodians.