No one is exactly certain why rusty blackbird numbers have been declining so drastically over the past half-century. “There’s no one smoking gun,” says Ben Schonewille, a Whitehorse naturalist and local station manager for the Society of Yukon Bird Observatories. Instead, he says there is likely a suite of causes behind the 90 per cent decline.
This spring, Schonewille and other experienced and trained birders, hoping to prevent the extinction of this once-common wetland resident, are urging the rest of us to pitch in and help determine just what is happening to Euphagus carolinus.
The International Rusty Blackbird Spring Migration Blitz 2014 has been underway since March in the U.S. As the birds progress along migration routes from the hardwood forests of the American Southeast to their northern boreal breeding grounds, which stretch from Newfoundland to Alaska, ornithologists and amateur birders, representing all degrees of experience and skill, are being asked to join the effort to determine what rusties are up against.
Over the past decade, ornithologists have been able to monitor birds in their winter ranges more readily than along the spring migration paths, especially at the northern end, near the boreal nesting grounds. The rusties disperse over a wide area in the North, and in much of the Yukon and Alaska there are far fewer birders to monitor them than there are to the south.
“This is the first time we’ve held the spring blitz,” says Cameron Eckert, president of the Yukon Bird Club. “We sort of know where rusties are breeding and where they’re wintering,” says Eckert. Something is happening in the rusties’ world. Could contaminants be a culprit? Habitat destruction is likely a major reason for the birds’ decline. Rusties need forested wetlands to survive. They are very habitat-specific.
In much of their winter range, wetlands are being drained to make way for construction, logging and agriculture. And, to add irony to injury, rusty blackbirds are caught up in the general vilification of blackbirds - primarily red-wings, grackles, and the non-blackbird starling - which are considered agricultural pests. Meanwhile, among blackbirds, it is the non-rusties that thrive on the cleared fields. As Eckert puts it: “The rusty has become emblematic for conservation of boreal species at risk.”
Both Schonewille and Eckert stress that birders don’t have to be highly trained ornithologists to be a great service in monitoring rusty blackbirds during the blitz. That’s especially true for Yukon. There are few other species in the territory that can be mistaken for rusties, they say. Brewer’s blackbirds, which do resemble rusties, remain south of the territory for the most part. There are only a couple sighting of Brewer’s here each year.
“The big identification challenge,” says Eckert, occurs in the fall when rusty males lose the blue-black gloss in their feathers and the brilliant yellow colouration in their eyes. In autumn, long after the spring blitz, they can be mistaken for brown-headed cowbirds.
“The first rusty blackbirds generally show up in the Yukon about the third week of April,” he says. “This year is maybe a little colder than average but about normal. That’s when we expect to see the first birds, but the main migration push is in the last week of April and first two weeks of May.” The earliest recorded sighting is April 12. “In the Yukon the migration continues in dribs and drabs right through the end of May.”
Good places to look for rusties are marshy areas with nearby shrubs and trees. In Whitehorse, the marsh on Quartz Road is readily accessible. Rusties show up in the Hidden Lakes area, at McIntyre Creek and in many other nearby wetlands.
The Yukon Bird Club is holding a field trip that will focus specifically on rusty black birds, on April 29. Pam Sinclair, Canada Wildlife Service ornithologist and co-chair of the steering committee of the International Rusty Blackbird Working Group, will lead the tour. Greg Brunner and Cynthia Hunt will lead a similar expedition at Henderson Corner near Dawson City on May 17. For more information on both field trips and on participating in the blitz contact yukonbirdclub@gmail.com
Individual birders are urged to watch for rusties throughout the April and May. Detailed information on blitz protocols and how to contribute data can be found at http://rustyblackbird.org/outreach/migration-blitz/
Eckert will be proofing the data contributed to the eBird site (ebird.org) before it’s made official in order to prevent errors slipping through. Each region covered by the blitz will be served by such data monitors.
The blitz will be repeated over the next two years and it’s hoped that by the end we’ll have a better idea of where the rusties are congregating along their migration routes and what habitats they are using.
Eckert stresses that beyond the much-needed data, there is a “huge awareness component” to the blitz. “Many people may have never heard of rusty blackbirds or they may not know that a common species in the Yukon is in a really critical decline throughout its range.”
As well, a blitz will help convince folks that an individual bird watcher, even the most casual of bird enthusiasts, can contribute to the conservation of a species. “A blitz like this has the potential of being beneficial to the species but also extremely rewarding for those who participate.”
So can all the new, improved rusty blackbird data help save a species and their environments? Some people may fear that ever more cautionary data can’t make a real difference. There are, however, plenty of land users, business people and politicians who comprehend the urgency of wildlife conservation in general and the threat to rusties specifically, says Eckert. Updated information can affect how we shop, how we modify our environment and how we vote. The more we learn the more we have to share with those who care.
“With the blitz, citizen science will be put to use,” adds Schonewille. “And it’s great to put our dot on the map.”
This column is co-ordinated by the Yukon Research Centre at Yukon College with major financial support from Environment Yukon and Yukon College. The articles are archived at www.yukoncollege.yk.ca/research/publications/newsletters_articles