Visitors to the dams this week have noticed that the primary sustained some dam-age. Our forward-thinking beavers invested their repair energy in the secondary dam, keeping the water at the gates. Jon says this morning they have done some major repairs on the first dam, using high bushy willow that makes the structure look a little madcap and creative. They haven’t mudded it yet, but firsts things first. It’s a start.
In the meantime, its time for the frog chorus again. Every year around this time we get a couple mornings with enormous frog song, as the male tree frogs gather in hope of luring a mate. Here’s what I said about it last year:
Last night’s visit to the dam showed four rascally kits, a yearling, and a very loud chorus of Pacific Tree Frogs. I remember when they showed up last year: (January 27th) after a rain, all at once, almost as loud as traffic. These are the males who come to gather and advertise for a mate. They use “ephemeral” wetlands that temporarily hold enough water for mating, but won’t run as great a risk of their offspring getting eaten by fish.
In the days after their population explosion we got our first scaup visitors, and oddly all the frog song got alot quieter. Turns out that scaup are carnivores, and they probably climbed this creek looking for the tastey makers of that song. I thought at the time that the song ceased because the adults been eaten, but actually the “mating advertisement” ceased because the campaign had been successful. Procreation had occurred and eggs were laid. I’m sure the Scaup enjoyed the tadpoles.
The 2008 state of the estuary report says that scaup are declining in number in practically every watershed in the Bay Area. Except Martinez, where there were flocks of 30-50 seen for the very first time.
Listen for the frogs and watch out for their predators. Apparently the females don’t make any noise and that’s how the males know who to breed with. I read that they sometimes accidentally choose a soft-spoken salamander by mistake. Keep that in mind while you enjoy them, and make a noise or two just to be on the safe side.
They seem to be farther down this year, more towards the fourth dam. I think Hess scraped away their favorite places. Hmm. Some of mine too.
Keep your ears open!
Photo: January 2010 Cheryl Reynolds
