Keweenaw Raptor Survey

The Keweenaw Peninsula is located on the shoreline of Lake Superior in Michigan’s Upper Peninsula.  Brockway Mountain is located on the Keweenaw Fault and climbs to a height of 1,328 feet above sea level and 726 feet above the surface of Lake Superior.

The annual spring migration of raptors past Brockway Mountain has long been recognized, but remains little studied.   An extended raptor survey is necessary to obtain a picture of the long-term pattern of migration, accounting for year to year variability.  Data gained from this survey will contribute to the knowledge of raptor migration in the Lake Superior region, including the effects of possible climate change and lake-influenced weather patterns on raptors.

Copper Country Audubon Club (CCAC) and Laughing Whitefish Audubon Society (LWAS), will contract  with a qualified observer, to conduct a survey of migrating raptors at Brockway Mountain during the spring migration period during the years, 2010 to 2012.  A committee of four people will organize and manage the project.  The committee is charged with establishing a count protocol, daily count times, season start and end dates, hring the expert counter, finding lodging for the counter in the Copper Harbor area, and arranging for use of a snowmobile.

Download the project specifics and estimated annual budget.

Raptor Migration in the Keweenaw

For migrating raptors, the 350 mile long expanse of icy blue water known as Lake Superior presents a tremendous obstacle to north-bound spring migration.  The south shore of the Lake is noticeably uniform with the exception of the northeast protruding Keweenaw Peninsula that terminates 70 miles from its base at Keweenaw Bay with some 70 miles of water remaining to mainland Canada.  To raptors this apparent land-bridge is like a Northwest Passage—one that initially looks very promising, but actually fizzles out well short of the desired goal.  For most species of land-loving hawks the Keweenaw’s gradually tapering peninsula concentrates hawks further with every mile until it ends as a cul-de-sac in Lake Superior.

This geographic feature, while most likely a waste of valuable time and expended energy for most hawks, provides one of the largest concentrations of spring raptors and perhaps the best viewing conditions in the Upper Midwest.  The site where Keweenaw raptors are at their peak concentration is Brockway Mountain, a narrow east-west oriented ridge nine miles from the Keweenaw’s terminus.  Situated less than a mile south of Lake Superior near the town of Copper Harbor, Brockway is the most northerly and prominent of a series of parallel ridges running along the spine of the Keweenaw.  For hawks carried along the peninsula on southerly winds, it acts as a funnel for movement further toward Keweenaw Point, where most appear to turn around and come back down the Keweenaw Peninsula.  This two-way flow of hawks past Brockway Mountain, and the viewing location at 1328 ft (726 ft above Lake Superior level) combine to produce two things very uncommon at hawk-watching locales:  hawks migrating in two directions simultaneously, and eye level views of the birds!  Indeed few things in nature are as striking as an eye-to-eye view of a Golden Eagle, its golden nape glinting in the sun against a backdrop of distant trees.

Despite Brockway’s obvious charm, it has received little attention when compared with well-known raptor migration sites like Hawk Ridge (in Duluth) and Whitefish Point Bird Observatory. The most detailed study to date was one conducted from 2 April-31 May 1992 by John Peacock (with an average of 6.8 hrs/day on 57 days).  During this count he tallied 15033 eastbound and 7191 westbound raptors of 16 species, for an average of 263.7 raptors per day. The westbound birds, less than half the number of the eastbound, are most likely birds that have already been to the tip of the Keweenaw.  An interesting question which yet remains is where the other 7842 eastbound raptors which were not re-tallied as westbound at Brockway Mountain went. A minority may have actually crossed Lake Superior (species like Sharp-shinned, and Rough-legged Hawks, and Northern Harriers are known to cross large bodies of water), but it is most likely that the majority dispersed throughout the Keweenaw after reaching the tip, possibly following the south shore back to the mainland U.P. Additionally, raptors may have cycled past Brockway Mountain on several eastward loops, returning west past Brockway Mountain the first few, and then moving along the south shore after several runs.

While yielding interesting data, the Peacock study has not answered all of the questions about Brockway raptor migration.  From occasional birding forays and brief counts by other observers a picture has begun to emerge: starting in early March when deep snow clothes the seasonal road-system, the migration of adult Golden and Bald Eagles begins. In April, Sharp-shinned and Red-tailed Hawks become more common until mid May when Broad-winged Hawks reach their peak numbers. In June, when most people think migration is over, birds are still moving at Brockway, but they are largely immature Broad-winged Hawks.  A full season of raptor migration at Brockway—encompassing the early March to early June period—has never been surveyed.  A full season survey would also provide data linking large hawk movements at Brockway with specific weather and wind patterns, enabling birders to predict the passage of hawks.  In addition, with only one survey completed before, it is impossible to know what the actual frequency, abundance, and timing of migration most species of raptors actually have; each year is probably slightly different and it is not safe to make judgments based on one season.

With this object  in mind, Copper County and Laughing Whitefish Audubon Societies, have decided to partner on organizing and managing an extensive spring count of raptors at Brockway Mountain.  To successfully pull this off we will have to put a great amount of time into developing, managing and raising money for the count.  We have proposed a three-year study, to monitor raptors at Brockway on three successive springs from early March through early June.  The logistics are challenging. Finding a veteran hawk-watcher willing to brave long counts day after day in harsh weather is a not an easy task. Starting the count in March when Brockway Mountain Drive is usually covered by several feet of snow will rule out easy access to the best viewing site without a snowmobile. In order to pay an expert hawk counter to do the count, rent lodging for him/her, hire a snowmobile for commute, and take care of many additional expenses, we will need to raise at least $6,000 per year. This is the single largest obstacle to the Brockway count, as for our volunteer clubs, the treasury has never been well endowed with funds.  Therefore we are asking for your support and those of others you know if this project seems important to you.  Any donation, of any size is a welcome addition. We encourage birders interested in the Brockway spectacle to come and see for themselves, particularly during the peak migration period

For more information on Brockway Mountain raptor migration see The Birds of the Keweenaw Peninsula, Michigan by Laurie Binford, pages 258-266.

Text for this page was written by Zach Gayk

WHO WE ARE:

The Keweenaw Raptor Survey is a joint project between Copper Country Audubon Club and the Laughing Whitefish Audubon Society. The KRS also is partnered with Michigan Audubon Society. KRS is managed by a four person volunteer committee including two individuals each as representatives of CCAC and LWAS. In addition the managing committee, KRS hires a field staffer as the spring raptor counter.

Contact email:

[email protected]

2010 Spring Counter: Max Henschell

Max Henschell grew up in northern lower Michigan along the Lake Michigan coast. Though always interested in the outdoors and nature, his interest in birding was sparked 6 years ago by a single Magnolia Warbler. While working on Isle Royale, Max came across the bird in the middle of the trail. With little knowledge and an entire field guide to look through, it took him nearly an hour to identify. Throughout the summer his interest in birds grew. But since that summer, Max’s interest in birds and birding has become a passion. Max has been an active birder in the Keweenaw and Upper Peninsula for the last 5 years. He has had the opportunity to bird in many birding “hotspots” across the country including the Rio Grande Valley and Southeast Arizona, with a life list of over 500 birds in just a few short years. Max has worked as the waterbird counter at Whitefish Point Bird Observatory and at Seney National Wildlife Refuge as a marsh-bird surveyor as well as volunteering at Patagonia Lake State Park in Arizona as a bird walk leader and with the Manitou Island Bird Survey. Max will be completing his master’s degree from Michigan Technological University in grassland bird ecology in March before joining the KRS.

KRS Managing Committee

Greg Cleary