WV Wildlife: Loggerhead Shrike Study
MONROE COUNTY, WV (WCHS/WVAH) —
Recently, on a cloudy and drizzly day across the Greenbrier Valley, we took a hike through a pasture with DNR Biologist, Richard Bailey, and some veterinarians.
Their goal? To catch a bird.
Not just any bird, though. One that is clever and unique--the loggerhead shrike.
The first pasture that we tried, in Greenbrier County, wasn’t a success. An unbanded shrike was seen, but the bird—for whatever reason—wasn’t interested in the ‘bait’, a couple of cages with mice in them. No worries, though, the mice were in a smaller cage that prevented them from being harmed. Perhaps this particular shrike was caught before? Bailey says these birds have a good memory—and once they’re caught, you won’t catch them again.
You have to sneak up on these predatory songbirds--you heard that right. These songbirds can be ruthless with their prey--actually impaling them onto sharp objects. This is a clever adaptation, though, given their lack of raptor talons.
After having no luck on a cow pasture in Greenbrier County, we decided to try a wind-swept ridge in Monroe County; that’s where the luck changed!
It probably wasn’t more than 15 minutes later that a mature shrike, a male, was captured in one of the cages out in a field.
The clicking noises that the bird was making made it clear—it wasn’t happy, but little did the shrike know that biologists are only trying to help in the long-run. These particular shrikes have been declining at an alarming rate--about 2-3% per year, and Bailey is trying to find out why.
"Everywhere you find this bird, it is in steep decline. These shrikes are actually a newly described sub-species with a very small population--this is why we are doing work. It's possible that this sub-species only has 500 pairs left in the world", said Bailey.
Feather samples--used for genetic analysis--were taken and the bird was banded. The shrike’s beak is so strong that only certain types of bands can be used!
"Shrikes, given that they are unique in a lot of ways, can crush aluminum bands in their beak because they're so strong, and so, I use stainless steel bands", said Bailey.
Before the shrike was set free, blood samples were taken, too, along with measurements and weight.
Shrikes, given their unique style of hunting, need sharp objects--and Bailey suspects that may explain their decline through habitat loss. Hawthorns are perfect for them, but with clear-cut farming now days--these plants aren’t as widespread anymore. Thanks to sinkholes in the Greenbrier Valley, though—owing to the Karst topography structure there—hawthorn-filled divots still remain. Farmers simply don’t want to risk their equipment in trying to clear brush from these small dips.
Bailey says this type of habitat is crucial for the future of the loggerhead shrike.
"We try to work on habitat. Habitat's an easy thing. If you look at this pasture here, this is a unique pasture. You see shrubs, scattered shrubs--it looks like the way farms use to look like 100 years ago. We try to work with landowners, private landowners, to actually let some hawthorns stay in their pastures. Here in West Virginia, hawthorns are absolutely what you want to have.”
Let's hope--for the shrike’s sake--that hawthorn bushes can begin to thrive like they once did.
- To visit the West Virginia Division of Natural Resources homepage, just click here.