Yes, kestrels are found in Wisconsin. There are two species of kestrel that reside in the state – the American kestrel and the merlin. Kestrels are small falcons that are known for their ability to hover in place while hunting. They are a common sight in both rural and urban areas of Wisconsin.
What types of kestrels live in Wisconsin?
The two kestrel species found in Wisconsin are:
- American kestrel (Falco sparverius)
- Merlin (Falco columbarius)
American Kestrel
The American kestrel, sometimes referred to as the sparrow hawk, is the most common and widespread kestrel species in North America. Some key facts about American kestrels in Wisconsin:
- Abundant summer resident and breeder across the state.
- Migrates out of the state in winter, though some individuals may overwinter in southern Wisconsin during mild winters.
- Nests in cavities in trees, man-made structures like nest boxes, or on building ledges.
- Male has colorful plumage with blue-gray wings and a rusty colored back and tail.
- Female’s plumage is less colorful with a rusty back and barred tail.
Merlin
The merlin is slightly larger than the American kestrel. Key facts about merlins in Wisconsin:
- Uncommon summer resident and breeder in the northern half of the state.
- Migrates through the state in spring and fall.
- Nests in tree cavities in coniferous or mixed forests.
- Male is slate-gray above with a streaked chest.
- Female is brownish above with heavy streaking below.
Where are kestrels found in Wisconsin?
Kestrels can be found in a variety of open and semi-open habitats across Wisconsin, including:
- Grasslands
- Prairies
- Agricultural areas
- Meadows and fields
- Open woodlands
- Forest edges
- Urban and suburban areas
American kestrels are widespread and can be found statewide during the summer breeding season. They are absent from northern Wisconsin in the winter.
Merlins primarily breed in northern Wisconsin and migrate through the rest of the state. They are more closely associated with forested areas than the American kestrel.
American Kestrel Habitats
Some specific habitats frequented by American kestrels in Wisconsin:
- Grasslands – nest in isolated trees or structures, forage over open areas
- Prairies – common in tallgrass prairies like those in central Wisconsin
- Agricultural areas – use trees in hedgerows or shelterbelts for nesting and perching
- Pastures – may nest in cavities in old wooden fence posts
- Meadows and fields – often seen perched on power lines overlooking open areas
- Urban areas – nest on building ledges and feed on pigeons and house sparrows
Merlin Habitats
Some habitats used by merlins in Wisconsin:
- Coniferous forests – nest in conifers of northern Wisconsin
- Deciduous forests – nest in tree cavities, often old woodpecker holes
- Forest openings – forage along edges and openings within forests
- Wetlands – sometimes nest in trees around bogs and marshes
- Parks & Cemeteries – merlins utilize trees in urban green spaces for nesting
What does a kestrel look like?
Kestrels are elegant, slender falcons. They have long, pointed wings and a long tail. Their heads are rounded with a neat facial pattern. Here are some more details on the plumage of each species:
American Kestrel
- Males have blue-gray wings and rusty colored backs and tails
- Females have a rusty back and barred tail
- Both sexes have two bold black stripes on their faces
- Their breasts may show varying amounts of dark spotting
- Talons and beak are yellow-orange
- About 9-12 inches in length
Merlin
- Males are slate-gray above with a streaked chest
- Females are brownish above with heavy streaking below
- Plain facial pattern
- Orange bands can be seen on the tail at close range
- Talons and beak are bluish-gray with a yellow base
- About 9-12 inches in length
When are kestrels present in Wisconsin?
The seasonal occurrence of kestrels in Wisconsin is:
American Kestrel
- Summer (breeding) – present statewide from approximately April through September
- Winter – absent from northern Wisconsin, may overwinter in southern counties during mild winters
- Migration – spring migration is March through May, fall migration peaks in September and October
Merlin
- Summer (breeding) – found in suitable nesting habitats primarily across northern Wisconsin from May through August
- Winter – migrate south out of Wisconsin from September to November
- Migration – migrate through the state April-May and September-November
The American kestrel has a more extensive summer range and is more likely to be encountered statewide during summer. Merlin populations are concentrated in the North during nesting season. Both species migrate out of northern Wisconsin for winter but American kestrels are partial migrants and some remain statewide year-round.
What do kestrels eat?
Kestrels are carnivorous and feed mostly on small mammals, birds, reptiles, amphibians, and insects. They hunt by perching and scanning for prey or hovering in place.
American Kestrel Diet
American kestrels feed on:
- Small mammals – voles, mice, shrews, bats
- Small birds – sparrows, swallows
- Large insects – grasshoppers, dragonflies
- Reptiles – lizards, snakes
- Amphibians – frogs, salamanders
Merlin Diet
Merlins take a wide variety of small birds:
- Songbirds – juncos, goldfinches, sparrows
- Shorebirds – sandpipers, plovers
- Game birds – quail, grouse
- Small mammals – voles, mice, bats, squirrels
- Insects – mainly large species
Merlins are able to take down larger bird prey than the American kestrel thanks to their greater speed and maneuverability in flight.
How do kestrels nest in Wisconsin?
Kestrels breed in Wisconsin during the summer months. Here are some details on their nesting habits:
American Kestrel
- Nest in cavities in trees, nest boxes, or building recesses
- Do not build an elaborate nest, just a scrape in the bottom of the cavity
- Clutch size is 3-5 eggs
- Incubation is 30 days
- Fledging occurs at 30 days
Merlin
- Nest in old woodpecker cavities and natural tree hollows
- Lays 3-6 eggs
- Incubates eggs for 28-32 days
- Young fledge at 28-30 days
American kestrels are more adaptable to nesting in human-made structures. Merlins rely more heavily on finding suitable natural tree cavities.
What is the kestrel population status in Wisconsin?
Kestrel populations face some conservation threats in Wisconsin:
American Kestrel
- Populations declining in parts of range but still abundant in Wisconsin
- Habitat loss and pesticide use may impact numbers
- Nest boxes help provide nesting sites
Merlin
- Listed as a species of Special Concern in Wisconsin
- Sensitive to habitat loss in northern forests
- Breeding populations thought to be declining in state
While still common, the American kestrel has shown declining trends in parts of North America. Providing nest boxes helps boost kestrel numbers. Merlins have a smaller population in Wisconsin and loss of nesting habitat in northern forests is a concern. Monitoring and protection of their habitat can help merlins.
Conclusion
Kestrels hold an important place in Wisconsin’s avian ecosystems. Their acrobatic hunting skills and cavity nesting habits make them fun birds to observe. The American kestrel can be found statewide during summer and is more numerous. The merlin is less common and concentrated in northern Wisconsin. Both species migrate out of the state for winter. Habitat loss and other threats require ongoing monitoring of kestrel populations. Suitable habitat protection and maintenance of nest sites will help ensure these falcons remain a part of Wisconsin’s natural heritage.