Eggs
From mid-July through early August American bullfrogs deposit their eggs in vegetation along the margins of lakes and ponds. Each adult female will deposit as many as 20,000 or more eggs in a single jelly mass.
If a site is being monitored rigorously it will be evident where reproduction is taking place because the males will have selected specific sites based upon the appropriate combination of vegetation to anchor and conceal the egg mass and a specific water temperature threshold of around 25 degrees Celsius or more. At most local lakes, reproduction will be concentrated at just a few spots along the lake margin. These sites should be selected consistently from year to year because the environmental factors that attract the bullfrogs to them will recurr annually - such as the character of the vegetation, sun exposure, water depth, and most importantly water temperature.
