Around 57,000 vulnerable tricolored blackbirds on Central Valley farmland were saved during this year’s harvest season, Audubon California said.
The saved birds represent 100 percent of the tricolored blackbird colonies on agricultural fields in the Central Valley, the organization said. Tricolored blackbirds, which once numbered in the millions, live almost entirely in California. Their population has been dwindling for years. A statewide survey completed in 2014 found the population of the species declined by 44 percent since 2011.
The birds establish nesting colonies in triticale, a plant that dairymen feed their cows, Audubon California said. Harvest season for triticale coincides with the birds’ nesting season. When the plant is harvested before young birds are large enough to fly, thousands of of eggs and nestlings are lost.
Since 2011, Audubon California collaborated with Western United Dairymen, Dairy Cares, the California Farm Bureau Federation and other organizations to form agreements with dairy farmers to delay harvests and allow the young tricolored blackbirds time for their wings to grow large enough to fly – which takes approximately 40 days.
This is the first year every colony found in an agricultural field was protected.
In 2015, the California Fish and Game Commission voted to designate the species as a candidate for the state endangered species listing.