Beginning in the autumn
of 2012 the Great Lakes Commission began a collaborative project to document
bird distribution in the offshore waters of the Great Lakes. One of the ultimate goals of this project was
to use the bird distribution data collected to help inform wind energy
developers about important bird areas and consequently help mitigate the
negative impacts of wind farms on birds that use the open waters of the Great
Lakes. Data is collected for this
project via aerial surveys, and I am part of a team of observers that makes
weekly flights over Lake St. Clair, the Detroit River, and western Lake Erie
recording and mapping bird locations.
Lake St. Clair lies
between lakes Huron and Erie connecting to the two through the St. Clair and
Detroit Rivers, and even though it measures close to 24 mile across at its
widest point it’s rarely included as a member of the Great Lakes. Despite its small stature in comparison to
Superior or even Erie, Lake St. Clair is an incredibly productive fishery and
one of the most important migration staging areas for ducks, geese, and swans
in North America. Because Lake St. Clair
encompasses over 400 square miles of open water but rarely exceeds 20 feet in
depth the entire lake is capable of supporting aquatic plants that provide the
habitat and food resources necessary to support strong populations of smallmouth
bass, walleye, and muskie and hundreds of thousands of waterfowl every fall and
spring.
|
Picture
taken during our winter aerial survey work over Lake St. Clair that contains
over 1700 canvasbacks. |
On any given survey
it’s not unusual for us to see a host of different bird species including bald
eagles, northern harriers, common loons, tundra swans, coot, and any number of
different dabbling duck species; however, if one is looking for a headliner,
diving ducks certainly steal the show.
Canvasback, scaup, and redheads are all members of a guild of ducks
collectively referred to as diving ducks because they often feed by diving
underwater to eat aquatic plants or small invertebrates and all three species
stage in staggering numbers on Lake St. Clair during October and November. Our peak estimates of all diving ducks on
Lake St. Clair and western Lake Erie have exceeded over a half a million ducks
during peak fall migration! To put this
in perspective, on one particular survey we counted 262,200 canvasbacks. The entire population of canvasbacks as
estimated by the U.S. Fish and Wildlife Service in the spring of 2012 was
759,900 meaning that approximately 36% of the entire population of canvasbacks
was on Lake St. Clair on that one, single day.
Furthermore, we have encountered a flock of diving ducks that covered
approximately 12 square miles of water and through a series of photos we
estimated that group to contain at least 350,000 ducks.
|
Picture
taken during our winter aerial survey work on Lake St. Clair that includes
canvasbacks, scaup, and redheads. Notice
the muddy water that is likely an indication these birds were feeding prior to
being alerted to the presence of the airplane. |
Perhaps the most
intriguing aspect of Lake St. Clair isn’t just that it supports booming fish
populations and hundreds of thousands of birds, but that it does all this while
at the same time being in millions of people’s backyards seeing as it’s only a
hop, skip, and a jump from Detroit, Michigan.
This proximity to people is a bit of double edged sword because Lake St.
Clair offers a tremendous number of folks an opportunity to hunt, fish, and
appreciate Michigan’s natural resources, but ultimately it’s this proximity to
such a heavily altered and developed landscape that causes a multitude of
problems for the lake. Negative impacts
from invasive species, decreased water quality, and shoreline development can
all be observed on Lake St. Clair, and although wind energy is largely
perceived as green energy, without careful planning offshore wind turbines
could have significant impacts on waterfowl and other waterbirds. Although most research suggests mortality
caused by collisions between waterfowl and wind turbines is minimal, it is
likely large wind farms will exclude ducks from using large portions of the
lake as they tend to give these turbines a wide berth. This being said, it will be critical for wind
energy developers to avoid areas of the lake that are important feeding and
loafing areas for the birds and corridors that help connect these areas if Lake
St. Clair is to continue as an area of continental significance to
waterfowl. The thought of depriving my
child or your child of the opportunity to see 10,000 canvasbacks fill the
western sky as they arrive on Lake St. Clair fresh off their travels from the
windswept prairies of Canada is not a thought I am comfortable with.
|
Canvasbacks
and scaup in flight observed during our second survey of this spring over Lake
St. Clair. |
Special thanks to my fellow observers Howie Singer,
Ryan Boyer, and Dave Luukkonen as well as Northwoods Aviation’s Derek
DeRuiter. Without these people none of
this work would have been possible.
Brendan Shirkey
Research Assistant
Michigan State University