Richardson Bay Audubon Center’s migratory bird tracker pings its first visitor
On April 24, Red Knot 458809 — a plump, red-breasted shore bird weighing just over 4 ounces — was captured and fitted with a digital radio tag in the Biosphere Reserve of the Upper Gulf of California and Colorado River Delta in Mexico.
The bird likely had journeyed there from the far south, perhaps as far as Tierra del Fuego, before reaching the warm shores of Baja California. On May 26, it flew north, resting for a few hours in the brackish waters of the Salton Sea. The next day, May 27, it flew up the Central Valley to a slough near Merced, turned west to the coast, passed through Santa Cruz and continued up to the Bay Area, where it rested for a few minutes at the San Francisco National Wildlife Refuge in Fremont. Then the bird was off again, flying north to Marin, where it landed for 2 minutes, 39 seconds at Richardson Bay before continuing north.
At Richardson Bay, a tag on the bird’s back sent a signal to a radio tower perched on a hill at the Richardson Bay Audubon Center and Sanctuary in Tiburon. Computers at the center pinged, registering the bird as it flew by and adding to the database that was tracking the bird’s flight in real time. It was a moment center staff had been awaiting for almost a year.
“We were so excited, and there was a big sigh of relief,” said Paige Fernandez, a biologist at the center. “Now we know for sure it’s working on a real bird.”
“It” is a Motus tower, or a tower fitted with a radio antenna that uses automated radio telemetry to track the migratory journeys of birds, bats and even insects.
The tower, erected by staff at the Audubon Center on Greenwood Beach Road last July, is part of the Motus Wildlife Tracking System, which was set up by Canadian conservationists and allows a community of researchers, educators, conservationist nonprofits and ordinary citizens around the world to share data on the migratory patterns of endangered species. According to the project’s website, there are 1,671 Motus receiver stations deployed in 34 countries.