Showy birds breed in Orange County

A male black-headed grosbeak claims a territory along the Barano Walk Trail in Mission Viejo. Photo by Anthony Gliozzo

Here's my latest column, scheduled to run in Saturday's Orange County Register. 


     If you’ve seen a flash of black and orange at your bird feeder recently, it was probably a black-headed grosbeak. Adult males sport showy black, white and burnt orange plumage in the spring while females remain relatively drab in shades of buff and brown. Grosbeaks are easily distinguishable by their large triangular bills. 
     These stocky songbirds from the cardinal family migrate this time of year from their wintering areas in Mexico to the western part of the United States to breed. The males generally migrate first so they can begin claiming a territory, with females arriving a few weeks later. 
     “It’s typical of the grosbeaks and orioles during spring migration. Males benefit from an early arrival by potentially securing a better breeding territory from which to court a female and raise young,” said naturalist Kurt Miethke of Tucker Wildlife Sanctuary. He logged his first grosbeak sighting in Modjeska Canyon on March 27. 
      “There’s even a hierarchy in arrival times by age of males,” he said. “Younger males arrive 12-16 days later than the older adult males, perhaps avoiding aggressive encounters with older, more experienced males.”
      Typically, a male black-headed grosbeak does not get its bright adult plumage until it is 2 years old, although first-year male plumage can vary.
     “Generally, only the young males with adult-looking plumage will have any chance of holding a territory and breeding that year,” Miethke said.
     The black-headed grosbeak is a fairly common breeder in Orange County, particularly in the oak-sycamore woodlands, with small numbers nesting in other habitats in the lowlands, he said.
     Highly territorial males spend time foraging for food and establishing and defending territories before the females arrive. Females build the nest while the males stand guard. She generally lays three to four eggs. During incubation, males and females share nest duties equally. Both parents tend the young for about 12 days.
     Their strong bills can easily crack seeds and crush hard-bodied insects or snails. Insects, especially beetles, spiders and other animals make up the majority of their diet during the breeding season. Fruits and seeds provide additional nutrients. Berries are particularly favored during migration.
     Watch for black-headed grosbeaks at bird feeders filled with sunflower seeds, and fruit and nectar feeders typically meant for orioles.