What does it take to rebuild a depleted species with birds bred in captivity? In the case of one of the longest-running breeding projects, it can take decades of patience and persistence – and hundreds of chicks added to the wild for every one that will go on to thrive.
A Loggerhead Shrike in eastern Canada. Photo by Larry Kirtley.
Our stories in the Washington Post on the rescue mission of the Florida Grasshopper Sparrow prompted a call from the research project that has been working for more than 20 years to save the Loggerhead Shrike in eastern Canada. Researchers there have valuable perspective on the laborious process of captive breeding.
“In our case, it’s years in the making,’’ said Jane Hudecki, coordinator for the Shrike conservation breeding program with Wildlife Preservation Canada. “It can be a tough field to work in.’’
Added Hazel Wheeler, the lead biologist on the project: “I’ve certainly read a lot of papers that speak to the long-term investment needed for a successful recovery program.”
There are a number of parallels between the shrike project and the mission to save the Florida Grasshopper Sparrow, which just had its first hatchings produced by captive birds in the wild. While both programs have figured out how to raise, release and establish mating pairs, questions loom around what it will take to restore the wild populations to strength.
Researchers put a transmitter on a Loggerhead Shrike to track its movement and migration. Photo by Sarah Matheson.
Wildlife Preservation Canada has released 1,300 Loggerhead Shrikes since the recovery program’s formation in 1998. Still, only about 20 breeding pairs remain in the areas of Ontario where the local subspecies settle for the spring and summer. “Basically, we’re just keeping the wild population stable,’’ she said.
The Canadian shrikes and Florida grasshopper sparrows are very different species, living on either end of the continent.
Of the 37 species in the Eastern U.S., the male Prothonotary is the only one that glows. His head is a saturated yellow-orange, earning him the nickname “Golden Swamp Warbler.”
Robert Rice, a veteran bird scientist who spent his career with the Smithsonian’s Migratory Bird Center, explained what happens: “They can eat so much fruit, it ferments in their gut and they go wobbly for a while,” Rice said.
It’s a magnificent sight, one I assumed I’d miss this year with our limited mobility. But the other day, wandering through the trees not 50 feet from our home, I noticed what looked like a new arrival. It was the first of a flock of Cedar Waxwings that gradually became an avalanche, all collecting insects as if their lives depended on it.
As birders all know, the more people get interested in birds, the more likely they are to want our state and federal government agencies to protect them.
Most of the answers are guesses, since the bird wasn’t tagged and certainly isn’t talking. But Andrew Farnsworth, a research associate with the Cornell Lab of Ornithology who specializes in migration, said the likely drivers are genetic migration instincts that go off track, lack of food back home and changing weather patterns that are becoming more frequent around the globe.
