female frogs

[phil]

happy new year to all.the other day (just after the ice had melted) i decided to clean the garden pond out and rid it of all the sycamore leaves that have accumulated. however, having drained about 50cm of water(no mean feat in itself as the pond is approx 1500gallons) i noticed some movement near one of the pots of water plants, but took no notice thinking it was a goldfish or shubunkin perhaps.anyway i removed all the pots of plants and started scooping leaves out with my landing net, only to find about 25-30 common frogs all swollen with spawn. i believe they are all female, and although i have observed frogs overwintering in the water before, this must make up the entire population of female frogs that use my pond. also i was unaware it was only females that did this