By Joe Sebastiani, Seasonal Program Team Leader
On Thursday, March 27, 9am to 3pm, I will be conducting a citizen science field trip to seek Rusty Blackbirds in New Castle County, participating in an effort called the Rusty Blackbird Blitz. This field trip is free for members of the Delaware Nature Society, and $15 for non-members. Rusty Blackbird (Euphagus carolinus) is a scarce, declining, and poorly known blackbird species that prefers to live and feed in swamps, bogs, beaver ponds, and other wooded wetlands. Unfortunately, over the last 40 years, this species is thought to have declined 85-95% across its range probably due to wetland habitat loss and disturbance. However, the causes of this steep decline are largely unknown, and the International Rusty Blackbird Working Group is leading the effort to learn more. Delaware Nature Society, with the help of University of Delaware PhD student Desiree Narango, is coordinating the Rusty Blackbird Blitz effort locally. Our field trip is part of this project to identify spring migration stopover sites that might be important to their survival.
Female Rusty Blackbirds are fairly distinctive, with a broad eyestripe, pale eye, and rusty feather edges.
Why go out and look for Rusty Blackbirds now? In Delaware, Rusty Blackbirds are migrating through the state from their wintering grounds further south. Rusty Blackbirds are on their way to the wild boreal forests of Canada and Alaska to nest in boggy wetland areas. The migration period in Delaware is roughly early March through mid-April. Rusty Blackbirds stop and feed along their migration route and can be found in wooded wetlands flipping over wet leaves, and poking along water edges for food. On our field trip, we will visit a variety of such wetlands looking for these birds, which travel in small groups of less than 100. We will also be listening for their spring song, which sounds like a creaky, rusty door hinge.
Here, a male Rusty Blackbird forages along a wet woodland, their favorite habitat on their wintering and breeding grounds.
Since March 1, Delaware birders have been looking for Rusty Blackbirds, and contributing their sightings to the Blitz project by entering them into eBird. Anyone can participate, and all you need is a free eBird account. When entering your sightings, choose Rusty Blackbird Blitz when indicating the type of birding you were doing. Thirty reports of Rusty Blackbirds have been entered into the system through today, and the biggest flock reported so far was 70 at Bombay Hook National Wildlife Refuge on March 22. 70 is a large number to see these days. In the past, their migratory flocks were referred to as “spectacular, noisy, and ubiquitous”*. This is certainly not the case today.
By the time breeding season rolls around for Rusty Blackbirds, they lose the rusty edges to their feathers and appear black with a pale eye. Rusty Blackbirds are very easily confused with the much more common Red-winged Blackbird, Common Grackle, and Brown-headed Cowbird.
Large-scale, international citizen science data collection projects like the Rusty Blackbird Blitz are helping scientists collect the data they need to learn more about declining species. The Delaware Nature Society is proud be a part of such an effort which could lead to more effective conservation of this species and the habitats it requires. What will we learn about their spring migration stopover sites in Delaware? Join our field trip on Thursday to help find out, and if you would like a chance to see Rusty Blackbirds. Register by visiting www.delawarenaturesociety.org or by calling (302) 239-2334. If you can’t g0 on the trip, keep you eyes out for these interesting blackbirds, and listen for their creaky, rusty-door-hinge sound. If you find some, get photos and note your location and the date. If you do not use eBird, but find these birds, you can report them to me by emailing joe AT delawarenaturesociety.org.
*(Avery, Michael L. 2013. Rusty Blackbird (Euphagus carolinus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu.)
Photos courtesy of the International Rusty Blackbird Working Group.