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Annual California Sea Otter Census


A standardized method to survey sea otters (Enhydra lutris nereis) was developed by WERC scientists and put into use in 1982 in California. Survey procedures involve counting animals during the "spring survey" -- generally beginning in April and ending in June or early July, depending on weather conditions. Two-person teams use binoculars and spotting scopes to count individuals from accessible stretches of coastline and from fixed-wing aircraft in the remaining areas. The counts made from shore are plotted on maps and then entered into a spatial database. The aerial counts are entered directly into a geographic information system-linked database in the aircraft. The survey records the total otter numbers, the number of dependent [...]

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Principal Investigator :
M. Tim Tinker, Julie L Yee

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