Year one results of Egg Mass surveys in Portland Metro Area and Coos Bay

Our amphibian citizen science program shows that amphibians love our preserves, both in the Portland Metro area, and on the coast. Preliminary results showed the presence of more than 1,000 egg masses…and we’re still counting!

Portland Metro Area: After classroom and field training, 15 citizen volunteers worked with TWC land steward Megan Garvey, and resident amphibian specialist Katie Holzer, to inventory amphibian egg masses at six TWC Portland-Metro Area urban Preserves. Surveys were conducted between February and April. Preliminary results included the presence of more than 1,000 egg masses, including all four local native amphibian species; red-legged frog, Pacific chorus frog, northwestern salamander, and the long-toed salamander

The first year survey results found long-toed salamander egg masses at both Pascuzzi pond and Knez wetland. Hedges Creek had northwestern salamander and red-legged egg masses as well as chorus frogs and rough skinned newt. Cedar Mill was rich in all four species surveyed. One pleasant surprise was finding a few pacific frog egg masses in a very small almost dried up pond at Hearthwood Preserve. No amphibian egg masses were found at Nyberg or Minthorn preserves. We found that the larger, wetter and less urbanized sites with greater  complexity and  habitat diversity supported a greater diversity of amphibians.

Coos Bay: In March the 8th grade students participating in the Coos Watershed Association’s Master Watershed Stewards program launched the first amphibian monitoring study at TWC’s Matson Creek Preserve. During the two day survey, 41 egg masses were found; including 35 Northern red-legged frog, 5 Northwestern salamander, and 2 Pacific tree frog egg masses within a 1,000 square feet study area. As a result of the unusually hot and dry spring, some of the ponded areas that provide key habitat dried up, leaving some of the eggs and tadpoles high and dry. Heavy rains a week later came in the nick of time, and saved many of the egg masses and emerging tadpoles.

The information collected in this year’s surveys provide the baseline for current use of our wetland preserves by native amphibian species. Over the next few years, we will  compare vegetation communities and habitat conditions in the areas where egg masses were present and absent. This information will be used to define desired future conditions, goals and objectives for potential enhancement, restoration and conservation strategies and actions.




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