City of Seattle, Seattle Public Utilities, Amphibian Egg Mass Counts 2002 - Current, Cedar River Municipal Watershed, King County, WA

This data package contains survey data beginning in 2002 for amphibian egg masses in five small kettle lakes (known as "14 Lakes") in the Cedar River Municipal Watershed, located in King County, Washington, USA. These surveys are conducted annually and are intended to be continued. The lakes range in size from 0.8 to 4.3 acres, have no perennial inlet or outlet, and were formed through glacial outwash deposits. The lakes are located at an elevation of 800 feet and are well suited for pond breeding amphibians because the lakes have no fish. Surveys were conducted annually, typically during the last week of March or first week of April, to coincide with amphibian breeding seasons. Surveyors walked, waded, or paddled the perimeter of each of the lakes during a survey, and tallied the number and type of egg masses that were encountered. Red legged frogs (Rana aurora) were of specific interest for the surveys, though egg masses of other species were noted during some survey years. The lakes represent the largest known breeding concentration of red legged frogs in the municipal watershed. The water depth of the lakes fluctuates year-to-year, which affected the feasibility of surveys. Lower water levels correspond to easier survey conditions: steep slopes and thick vegetation make surveying challenging when the water is high. Surveys were periodically cancelled during years where high water made surveying difficult or during staffing shortages. Counts of red legged frog egg masses across all lakes ranged between 24 and 1778 in a given year.