The Rusty Blackbird (Euphagus carolinus) has suffered a severe population crash in the past four decades. An estimate from 2004 put its population at two million birds. This represents a decline of 85%-98% from its population in the 1960s, and the species continues to decrease at a rate of 10% per year.
The causes of this decline are still not well understood. Even less is known about the Rusty Blackbird's habitat requirements and potential threats during spring migration. To that end, eBird is asking birders to gather and submit Rusty Blackbird sightings during the week of April 1 to April 7.
To address this information gap, eBird is calling on bird watchers for help. April 1-7, look for Rusty Blackbirds on their northward migration. The data collected will help identify important migration stopover locations and habitats for conservation and will help researchers examine whether long-term changes to key migration habitats are responsible for the species' decline. If you are interested in participating, please collect the following information, then submit your data to eBird, taking note of the following:Additional information, including identification tips, are available on the Rusty Blackbird project page. If you want to search specifically for Rusty Blackbirds, look in the same types of habitat you might expect to find other blackbird species, such as Red-winged Blackbirds. Check agricultural fields and wetlands, especially wooded swamps. Boyle's Guide to Bird Finding in New Jersey suggests Allaire State Park, Great Swamp NWR, Princeton Institute Woods, Scherman-Hoffman Sanctuary, Troy Meadows, and Whittingham WMA as reliable sites. Other locations may also be fruitful; I have seen a Rusty Blackbird at Trenton Marsh, for example.
1. Date, time, location of the observations. Area, traveling and stationary counts are preferred. Be as precise as possible when mapping your location.
2. Rusty Blackbird flock size, including an estimate of number of males vs. females. Answer 'yes' to the question 'do you want to report age/sex or add species comments' at the top of the eBird checklist page.
3. General behavior: flying, feeding, loafing (day), roosting (dawn, dusk, night). Put these in the species comments field.
4. Habitat: agricultural field, scrub-shrub wetland, forested wetland, shores of rivers or creeks, shores of lakes or ponds. Put these in general checklist comments field.
5. Comments: Please include "Rusty Blackbird Survey" in the general checklist comments section so we can determine whether you were specifically looking for Rusty Blackbirds during your birding expedition.
6. If possible please submit a complete checklist of the birds you identified on your outing, and answer 'yes' to the 'are you reporting all the species you saw/heard' question on the eBird checklist page. This will give us an idea of what other birds were in the area, as well as whether or not Rusty Blackbirds were associating with other blackbirds species during migration.
More information on Rusty Blackbirds is available from the National Audubon Society Watchlist and the Smithsonian Migratory Bird Center, which has research project devoted to the species.