Perhaps it was because it was the night of the Beaver Moon.
Whatever it was, two of Martinez's beavers made an appearance at sundown Wednesday while a dozen onlookers watched.
About 5:15 p.m., the first beaver swam out from its den along the banks of Alhambra Creek. He disappeared, but a few minutes later another beaver came out, swam near one of the colony's dams, grabbed a vine and brought it back to the den.
The event, organized by the community group Worth A Dam, was designed as a celebration of the beaver community in town.
Heidi Perryman, founder of Worth A Dam, said this is a special year to celebrate because the colony's male beaver found a new mate and they have a new baby to go along with another young beaver born in 2010.
Igor Skaredoff and his wife, Shirley, both attended. Both are members of Friends of Alhambra Creek as well as Worth A Dam.
Igor Skaredoff said it's important to support as well as learn from the wildlife that can be found in urban areas.
"The beavers are part of the ecosystem here," he said.
Kathy Epperson of Walnut Creek attended because she was curious after she heard Perryman talk about the beavers at Rossmoor.
"I thought it'd be fun," she said. "I've never seen a beaver in the wild."
Worth A Dam was formed in 2006 when the beavers were first spotted in the river. There have been arguments over the years whether the dams built by the beavers is destructive to the downtown creek.
There have been proposals to get rid of the animals, but Perryman's group has so far prevailed in allowing them stay.