Managed Wildlife Species
The Park District conducts management programs for a variety of wildlife species of concern, as well as for wildlife whose increasing population in the Metro area is of concern for the species, habitat and the public. Managing any wildlife species involves providing suitable habitat and maintaining a healthy but controlled population.
Bats are found in most of the Three Rivers Parks. They are most noticeable around dusk when they emerge to feed on flying insects. There are two types of bats in the Park District, tree bats and cave bats.
Tree bats include hoary and red bats, which spend their time in trees, under loose bark or under leaves. They do not form colonies and are not encountered in buildings. These bats are migratory and spend their winter in the southern states.
Cave bats include the big brown and little brown bats. These bats live in caves and manmade buildings, including barns and houses. The females form colonies to raise their young. The colonies can be as few as 10 bats, to colonies in the 1,000’s. In the Park District cave bats can be found in older barns and some buildings. Efforts are made to exclude them from buildings and staff have installed specially built bat houses to the outside of buildings to give the bats a place to live. In the winter, these bats move into caves along the Minnesota and Mississippi Rivers.
Currently, there is a fungal disease infecting and killing cave bats called White-nose Syndrome. This disease was first documented in Minnesota in 2015 and is expected to cause widespread mortality in bats over the next few years. Unfortunately, there is no management to stop this disease.
Beaver ponds provide valuable wildlife habitat for a variety of animals. Occasionally, beavers plug culverts, flood fields and forests, cut trees in recreational areas or cause other damage. The Park District uses private trappers to control beavers as necessary on park property.
The Park District has been managing Blanding’s turtles in the parks since the 1990’s. There are Blanding’s turtle populations in Crow-Hassan, Elm Creek and Murphy-Hanrehan Park Reserves. Blanding’s turtles are listed as a Threatened Species in the State of Minnesota, and the Three Rivers Park District populations are some of the best in the Twin
Over the years, Three Rivers’ wildlife management staff have conducted radio telemetry studies on the turtles in the three park reserves to learn about the habitats they use and where they make their nests. Blanding’s turtles are currently only tracked at Crow-Hassan Park Reserve to assist in scheduling prairie burns. The prairie habitat is important for the Blanding’s turtle nesting, so it is essential to know that the turtles are in the wetlands when a burn is conducted.
Canada geese have adapted very well to urban environments. The Park District uses summer roundups and special fall hunts to control numbers as needed. In some parks, the Park District uses a border collie to chase geese from picnic areas and golf courses.
The Park District began receiving reports of coyotes in 1990, by 1994 they were documented in all of our parks and park reserves. Nationally, they have moved eastward and now are in each of the lower 48 states.
Coyotes are considered canine predators and serve many benefits. Rodents make up the bulk of their diet and, although rarely taking an adult deer, they are a primary predator of fawns, helping to reduce the deer herd within the metro area. Coyotes have been known to also take young turkeys and geese, species that may also need population reduction.
Did you know:
Coyotes are smaller than you might expect. They are under 40 pounds, with most weighing between 18 – 28 pounds.
Coyotes are intelligent and able to adapt quickly, so it’s important to ensure that coyotes do not associate people with food - a primary reason that coyotes may become habituated to people. Of course, coyotes should never be fed by humans; unintentional feeding can be prevented by keeping pet food, garbage and bird feeders contained.
Educating park visitors is a key strategy of the Park District to prevent conflicts with coyotes. Hazing is the simple act of teaching a coyote to be afraid of people, keeping people and pets safe from harm. Most people use the acronym SMART to haze a coyote.
- Make yourself big
- Announce yourself loudly
- Repeat if necessary
- Teach others to do the same.
Park visitors need to be able to haze coyotes to ensure that coyotes in the metro are constantly aware of their surroundings with people. For more information or to report a coyote conflict, call 763-694-7840 or email wildlife@ThreeRiversParks.org.
Found in every county of Minnesota, the Eastern Bluebird is one of the most popular songbirds. Bluebird populations declined greatly from the 1930s to the 1960s due to habitat loss and competition from other cavity-nesting birds, especially House Sparrows and European Starlings.
One successful way to increase bluebird numbers is through the use of Bluebird trails. A bluebird trail is a series of managed nesting boxes. The key to the trail’s success is monitoring the boxes throughout the breeding season, April to August. Monitoring insures that the boxes are not occupied by undesirable species such as the House Sparrow, and makes it possible to intervene if a serious problem is detected such as ants in the nest.
Three Rivers staff from the Wildlife Section and the nature centers maintain and manage bluebird trails in nearly all of the parks. Three Rivers currently monitors over 600 bluebird boxes, which in 2015 fledged a total of 962 bluebird chicks. Volunteers assist with the bluebird monitoring in a variety of ways, closing up the boxes in spring, checking them weekly during breeding season, reporting nesting data and cleaning out the boxes in the fall. The Park District also participates in the Bluebird Recovery Program of Minnesota.
One of the groups of birds that are seeing a decline in population are grassland nesting birds, including Bob-o-links, Eastern Meadowlarks, Grasshopper Sparrows, Henslow’s Sparrows, Dickcissels, Northern Harriers and others. These species need native grasslands that exceed 100-200 acres for nesting and raising their young. The Park District has been creating large prairie complexes at Crow-Hassan, Murphy-Hanrehan and Carver Park Reserves for these and other prairie dependent species.
Prescribed prairie burns are timed to provide a variety of grass densities across the prairie. Three Rivers’ wildlife management has allowed the Henslow’s Sparrow, a state endangered species, to maintain healthy populations at Crow-Hassan and Murphy-Hanrehan. These species are tracked through songbird surveys.
The Purple Martin (Progne subis) is listed as a species of special concern in Minnesota due to documented declines over the past three decades and continuing threats to the state’s population. Historically, this bird nested in natural cavities such as woodpecker holes and dead snags, however, due to habitat loss and the ease with which this species is attracted to artificial structures, Purple Martins in Minnesota exclusively use nest boxes.
In 2004, Three Rivers’ wildlife staff attempted to re-establish a Martin colony by installing Martin houses at the Baker Campground beach and along the shore of Lake Minnetonka at Noerenberg Gardens. Due to tree plantings (Martins will not nest near trees), the houses were moved in 2006 to open locations at Baker National Golf Course, the swimming beach at French Regional Park, and at Eagle Lake Golf Center. As of 2008, all three colonies were thriving, and new housing structures were later installed at Noerenberg Gardens, Gale Woods Farm and Cedar Lake Farm.
With dedicated efforts from staff and volunteers, the newly installed sites also successfully attracted nesting Martins and remain active for six established colonies. In addition to their summer homes in Minnesota, these amazing birds migrate and spend their winters in Brazil.
Our highest recording of fledged Purple Martins was recorded in 2020 with a total of 377 young chicks produced from the six active sites.
For Martin colonies to be successful, careful monitoring and maintenance must be completed. The biggest threats to the colonies are competition for nest cavities by non-native, aggressive house sparrows and other native species, along with a variety of predators and other threats that can destroy the colony. While establishing the colonies has been a challenge, the efforts of Three Rivers staff and many helpful volunteers have paid off. The Park District submits all nest check data to the Purple Martin Conservation Association.
Want to know more about Purple Martins? Read about how we're protecting these birds in our parks, or listen to our Purple Martin podcast episodes of The Wandering Naturalist.
Three Rivers is committed to maintaining a viable population of white-tailed deer in the park reserves and some regional parks. Deer herds in the parks are counted annually through aerial deer surveys conducted by helicopter each winter.
Without control, deer populations increase to the point where they start to damage vegetation and deer/car collisions increase. Managed archery and shotgun deer hunts, as well as sharpshooters, are used to keep populations in balance with available habitat.