Sunday, July 15, 2012

Pacific chorus frog ~ 07/15/12 ~ at home

Pacific chorus frog / Sierran chorus frog / Pacific treefrog
Pseudacris sierra (also Pseudacris regilla and Hyla regilla)

This is the first healthy adult form juvenile I've seen completely out of the water this year. It still has a tiny bit of tail that's not apparent in my early morning photo. In addition to the juvenile shown above, I have 5 tadpoles left swimming around from an original 16 that hatched last year at the end of May. Yes, you read that correctly, I've been keeping the same tadpoles outside for almost 14 months now. Several online sites (see embedded links in the IDs above) state Pacific chorus frogs metamorphose within 2 to 2½ months and according to Wikipedia up to 5 months in captivity. Perhaps it's the artificial conditions I provided (variously a standard goldfish bowl, an extra large glass kitchen bowl, and a 5 gallon aquarium with either partially or fully changed fresh water every several weeks) that have kept them from transforming. My last full water change was last weekend.

So, over the course of the past year, I casually observed their feeding, development, and behavior that I haven't found specifically mentioned elsewhere online. In addition to sucking on algae, they voraciously eat duckweed roots, which leaves a considerable amount of leaf debris at the bottom of the containers. I've transferred this debris along with any remaining duckweed and a large algae covered rock with every full water change. The tadpoles seem to like burrowing themselves in the debris, and the almost-tranformed juveniles with all 4 legs will hide there for days while their tails get absorbed. After I switched out the 5 gallon aquarium for cold water white cloud minnows this past April, I started supplementing the tadpoles' diet with anacharis and small amounts of fish flakes. Other than one dead adult form juvenile, I haven't had anymore deaths. This has been nice for me, because it was rather gruesome to watch how the tadpoles aggressively scavenge dead bodies, including squashed bladder snails (bred like rabbits and were very difficult to eradicate). The tadpoles get quite bulky, approximately 3 times the size of the ½ inch juvenile shown here. The hind feet gradually appear first with very little change in body mass. Once the front leg stubs start showing, their body mass reduces quickly, and they get very twitchy, almost as if growing front legs is painful. Hmm, growing pains?

I'm hoping the remaining 5 tadpoles will successfully metamorphose. I'm still not sure what to do with the adults since my balcony is not likely suitable habitat, even though there are plenty of places to hide in and around planters and small flies from my compost bins. I do not want to randomly release them into the wild since Pacific chorus frogs could carry a fungus that can kill other amphibians. I may give them back to my friend who originally gave me the last of last year's seasonal batches of eggs. This year she found frog eggs as early as the end of January, 2 months earlier than the previous 2 years.