The Upper Mississippi River National Wildlife and Fish Refuge will be undertaking an emergency closure of the Mertes Slough heron colony beginning Thursday, May 23, 2013.
The heron colony is located near the Hwy 43/54 bridge between Winona, MN and Fountain City, WI.
Maps outlining the affected area will be posted at the Mertes Slough Boat Landing and are available at the Refuge office. The boundary of the 57 acre area closed to entry will be posted with signs in the field.
Winona District Manager Mary Stefanski said the closure is being undertaken to protect the nesting birds during a time when they are highly susceptible to nest abandonment due to human disturbance. This spring, high water conditions have created easy access to the colony by boat.
The colony is a unique biological attribute on the refuge and is home to over 800 great blue heron and great egrets during the nesting season. Last year, the colony produced an estimated 600 young herons and egrets.
The closure will remain in effect until July 12, 2013 when most of the young birds will be fledged. Those wishing to view the heron colony may still do so from outside the posted area.
For more information, contact the Winona District Office at 507-454-7351.