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Why are bald eagles in
Wabasha?
 Food!!!
Eagles’ primary diet is fish. Bald Eagles are
fishing raptors and prefer gizzard shad, which are abundant in the river
here in the winter.
During the nesting season, eagles are territorial. They don’t share their feeding territory. As the eagles’ nests sites in northern Minnesota and northern Wisconsin and southern Canada freeze over, the eagles are forced to move south in search of food. They prefer to fly only as far south as they have to and usually stop in
Wabasha. Some harsher winters will cause them to fly even farther south than here (Missouri, for example).
Why does the river stay open here?
From the base of Lake Pepin the rivers channel narrows considerably. The Chippewa River enters the Mississippi River at the south end of Lake Pepin. The volume of water leaving Lake Pepin and the volume of water entering from the Chippewa River cause the current to be so strong that the river remains free from ice for about three miles (from Reads Landing to just south of Wabasha) for the majority of the winter.
There are some times when the temperature is –30 to –40 degrees below zero. When temperatures are this cold there are times that the river can become blocked with ice breaking off of Lake Pepin or coming out of the Chippewa River. It can remain blocked for a few days, but will open again when temperatures return to the usual 20+ degrees. During this time the eagles may be forced farther south to find open water for fishing.
Eagles need open water to fish and feed. The open water between Reads Landing and Wabasha remains open naturally. There are other areas on the river that have open water because of human intervention – most typically locks and dams and power plants. Lock and dams have roller gates that, if left in the water over the winter, churn up the water keeping it open and injuring or killing any fish that may get too close.
Power plants pump warmed water back into the river. (The power plants use river water to cool their boilers and then release the warmed water back into the river). The NSP coal-fired power plant releases warm water into the Mississippi just north of Colville Park in Red Wing. That is why at most times you are able to see a number of eagles congregating in and around Colville Park in Red Wing. There is another coal-fired power plant south of us in Alma, WI.
The most typical meal of the eagle is gizzard shad (a non-game fish) because they are prolific breeders and in plentiful supply in the river. Eagles will also scavenge for food and in years of little snow cover will find everything from dead animals along roads to waste animal matter discarded by pork and chicken operations. Lead poisoning is a problem during low snow cover as eagles scavenge the gut piles left by hunters that may contain lead from slugs used to kill the deer.
Finding eagles on the river.
Spotting eagles on the river is usually quite simple once you know what you’re looking for. There are no other birds on the river this time of year with the size and the coloration of the juvenile and adult bald eagles. Look in the taller stands of cottonwood trees and then in the top third of the branches. You may see a large vertical black spot. If this black spot is very dark with only a few streaks of white on its body it is a juvenile bald eagle; if you see one with a white head and tail, you have just spotted an adult bald eagle. Juvenile eagles begin to get the adult coloring (white heads and tails) between the ages of 4 and 6 years. With each consecutive molt around the age of four, the juvenile eagle will gain more white feathers in the head and tail until virtually all of the feathers of the head and tail are white.
Usually in late March we begin to see some turkey vultures returning to the area, but their eating habits are different from the bald eagle. They are seen more often over the bluff tops than over the river.
By the end of March and early in April most of the eagles that have called Wabasha home for the winter will return to northern Minnesota, northern Wisconsin and southern Canada to lakes where they nest during the summer. These lake nest sites must thaw before the eagles can begin laying their eggs and supporting their soon-to-be-hatched chicks with food. Locally we have about 12 pairs of bald eagles that stay in our area year ‘round. These eagles nest in the backwaters of the Mississippi River and its tributaries.
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