We are fortunate to have a nice diversity of birds at Driftless Prairies. This listing will be “under construction” for the rest of my life!!! Click on the bird’s name and you’ll see tidbits of information. Here’s the references for those tidbits!
The most vulnerable time in a bird’s life is the egg stage and the nestling stage. Predators range from other birds to mammals to snakes. Even insects such as black flies cause death.
Each bird has a “signature” nest building design and preferred building location ; some use preexisting cavities such as woodpecker holes or nest boxes that we humans create for them. If they were all the same, it would be like a red neon sign pointing the way for predators.
Birds insulate themselves by fluffing out; this traps their body heat in the air surrounding their feathers, keeping them warm. For additional warmth, some will tuck their heads and feet into their feathers. Birds use their wings as raincoats. A cold rain can be very hazardous; if their downy feathers get wet, they lose warmth. Birds found in our northern climates during winter have a higher metabolism. They eat during the day and burn those calories staying warm at night. They can lower their body temps to stretch calories. Without food, these birds would not survive.
Birds found in wooded areas and forests depend on snags or standing dead trees. Nearly 1/3 of our woodland birds nest or forage for beetle grubs inside snags.
Habitat loss is reducing the numbers of our birds. Habitat is being destroyed by urbanization, farming, and degradation. Farming practices are changing but there’s much to be done. Degraded habitat can be restored with time and resources. Areas allowed to be overgrown with non-native bushes leave no food for the birds because insects aren’t adapting quickly enough to use non-native plants. This is devastating for migrating birds in need of food. McCormac has a great sentence in his article; “conservation of songbirds starts with conservation of native plants.”
Caterpillars are a preferred bird food source, even for chipping sparrows who are known to be vegetarians. Most warbler diets are 30% caterpillars and vireos are a caterpillar’s greatest fear; maybe this is why caterpillars have such great camouflage and emerge at night.
I love learning bird song. Many birds can be shy but if they’re singing, I know they’re around. Birds sing for a variety of reasons, the two most common reasons are territory marking and attracting a mate. It’s particularly interesting to hear the regional dialects of the same bird species or to hear the babies learning their song. Insects are crucial to the quality of song. Insects provide protein and other valuable nutrients to baby birds during their development and the quantity of insects available is important. I’ve often wondered how the birds can hear each other when it seems they are singing equally as loudly and simultaneously. This is overcome by singing louder, at a higher pitch, or more often and they alternate their singing time. Bird songs change for birds in open environments such as the country and closed environments such as urban neighborhoods and downtown areas.
Predation is a big concern for most birds. Generally, in a nesting season a songbird will lose a nest due to predation. Scientists are learning that merely having a predator nearby can change the reproduction of many songbirds; laying eggs and raising babies are high resource activities. It’s amazing that any songbirds reproduce!
Cornell’s All About Birds is an excellent website. Cornell’s site has info on bird identification, photos, videos, song/call recordings, habitat, life cycles, etc.
Ubitiquitous as these are, they are considered a marsh bird. After raising 2-3 broods per year, they will flock together in the hundreds of thousands. We consider them the true harbingers of spring.
Their habitat is marshy areas where they will nest in cattails or reeds over water. There’s a nice area for them across the highway. I had no idea how rare they were to see in our area until I began this listing, therefore, there will not be a reported sighting shown on any of the referenced maps.
This species feeds exclusively on insects.
Much like squirrels, they bury seeds and acorns, which are never retrieved, so we can attribute tree planting to these raucous, beautiful birds. Blue Jays are attributed to planting many nut trees. They carry the nuts for considerable distances and hide them in the ground. Many are never retrieved. Along with nuts they eat lots of invertebrates – one study estimated 1/5 of an ounce per day.
It wasn't that many years ago that the Eastern bluebirds were nearly extinct. This was due to loss of habitat as the lands were cropped with monoculture and also due to the house sparrow introduction. Thanks goes to the many volunteers who worked to build nest boxes and provide habitat for these birds. To lose them from our earth would be tragic.
Bluebirds eat by setting a perch, flying to the ground to eat the insect, then flying back to a perch. Because of this foraging behavior, they like to be in areas that have some openness to them, such as prairies and grasslands. They will usually eat insects in the spring and summer months but will never turn down a mealworm treat!! During the winter, they will eat fruits and seeds.
Jim has maintained a bluebird trail for many years; we call is the Hess Trail. A bluebird trail is simply a number of nest boxes that are monitored monthly. Our trail runs around our property and along Hwy N; to make this weekly checks, Jim rides his bike. We sent our numbers in to the Lafayette County Bluebird Society and to the Bluebird Restoration Association of Wisconsin. Check out the blog article, too.
Along with the references above, the North American Bluebird Society is another place to find answers.
Cute little birds that probe the bark of trees in search of insects. It only moves up a tree so when it reaches the top, it flies to the bottom and begins its spiral ascent in search of food.
This bird is named after the red robes worn by Roman Catholic cardinals. Unique to this species, the female will also sing and will sing year round rather than only during mating season. When they are excited, they will raise their crest.
Part of the mimic family, this bird rambles various songs amidst its mew-like cry. As part of the mimic family, their song is a single version of another birds’ call, whereas the brown thrasher repeats the songs in pairs.
Waxwings spend most of their time in flocks, appearing at times in the hundreds to eat berries. Some of the berries they eat are the invasive, nonnative honeysuckles. While this doesn't make them sick, it does change the color on the tips of their tails from yellow to orange. This could have a negative effect on mating; it's not been studied well enough yet.
These guys are known as the “leaders of the pack.” When you see one, you can be sure there are other birds coming after him, so if you’re out birdwatching, keep your binoculars focused! Chickadees are the more thoroughly studied of our birds. I read an article recently that put into focus how much they weigh. It's hard to grasp what 0.4 ounces means unless you work with weights regularly, but knowing a chickadee weighs about the same a 12 paperclips puts it into a perspective most of us are familiar with.
The other thing I love about these birds is their "Hey Sweetie" song. When I'm outside, I'm just certain they are calling endearments to me!!!
We love having these birds around all year. Unlike other birds similar in size, chickadees have denser plumage, which helps them to stay warm in these northern climes during the winter months. Also, unlike other birds, except the Tufted Titmouse, Chickadees have a physiological response in the autumn and winter. Because they cache their food during these colder months, they need lots of memory. As such, their brains become larger, most specifically, their hippocampus enlarges; this is the area of the brain that is responsible for memory.
Cowbirds parasite over 200 songbird nests by laying their eggs in them and letting the songbird, which is much smaller, raise their ever-growing baby. Providing enough food for this larger bird sometimes means the other nestlings don’t get enough, causing high mortality rates among the songbirds who are the targets of cowbirds.
These birds have a most awesome and raucous call with mating pairs vocalizing in unison. The adults look a lot like Whooping Crane juveniles. Most birds have an internal navigation system, but cranes do not and they have to learn their routes from their parents. Migratory routes are recalled via visual landmarks.
Crows are very social and can gather in roosts of over 500,000 birds. They are beneficial to humans as they eat many insects that are harmful to agricultural crops. There are a couple of great books about these extraordinary birds: The Gifts of the Crow and In the Company of Crows and Ravens . Learning more about them will provide a perspective that is much different from the “pest” or “nuisance” that some call them.
Aside from humans, the greatest enemy of crows are Great horned Owls. During the day, the crows can outmaneuver the owls but this is just the opposite at night.
When this guy showed up, I knew we were doing something right and when he showed up year after year, I really knew it!! Dickcissels winter in Argentina and when they migrate back to the US, they are known to pick the most optimal breeding sites; this means that they may or may not be back the following year.
When we first bought the land and came out birding, we didn't see Mourning Doves. It wasn't until a few years later that we saw and heard their haunting, yet lovely, call. I find it interesting that their flight silhouette is very similar to a kestrel and I wonder if that wasn't intentional so they were not viewed as prey.
Wisconsin Bird Sounds has a great recording of their mournful song.
In November 2011, Birds and Blooms magazine printed 10 surprising facts about mourning doves:
1- When they grab seeds off the ground, they are not necessarily eating them. Instead, they are stockpiling for digesting later. The seeds collect in the “crop,” which is simply an enlarged part of their esophagus.
2- They are primarily seed-eaters, not insect-eaters. They can and do eat weed seeds, which is certainly valuable to gardeners as well as farmers, or anyone living near overgrown vacant lots. (They do like corn, though.)
3- The cooooOOOOO-woo-woo-woo call is almost always uttered by the male bird, not the female, and is—wait for it—a wooing call, an enticement to a mate or potential mate.
4- When they sleep, their head rests between their shoulders, close to the body (they do not tuck their little heads under their shoulder feathers, like a lot of other birds do).
5- Their long, pointed wings are almost falcon-like in appearance, while their pointed tails are longer than those of any other doves. These “design features” enable the birds to fly fast. Mourning doves have been clocked at 55 mph!
6- When they lay eggs, it is almost always just two. (Singletons are rare, as are bigger clutches.) Incubation takes just two weeks.
7- Males and females work together to feed their new babies something called “crop milk” or “pigeon milk” for the first few days of their life. Rich in protein and fat, it resembles cottage cheese, is secreted by the adults’ crop lining, and is regurgitated to the little ones. Weaning is fast, though—by the fourth day of life, the diet starts to segue to seeds, and by two weeks, the youngsters are nearly fledged.
Nearly wiped out in the 1960s, this US emblem is making a great comeback. We have a mating pair in two different spots within 4 miles of us. It's not unusual to see 2 of them circling above or perched in a tree. Even though we often see them, we never tire of the awe they inspire.
Described as dipped in raspberry juice, this little bird loves checking out our feeders for sunflower seeds. These birds also enjoy the seeds remaining on their stalks during the winter.
Our eastern birds have descended from cage birds release in 1940s in New York. At that time they were known as Hollywood Finches. The color variation of this bird have been documented by Cornell and are typically due to what they eat.
This is the only woodpecker that feeds on the ground and the only brown-backed woodpecker.
There are two types of northern flicker -- the yellow-shafted, which is considered the eastern species and red-shafted, which is the western species. This difference is determined by the coloring on the underside of the wings. Their song is similar to the pileated woodpecker so you'll have to listen close to know the difference!
This bird loves to use shed snake skins for making its nest; the reason is not known. It nests in holes, which makes it the only eastern flycatcher to do so. We find him hanging out at our garden - he can get straw, snake skins, and bugs all in one spot!!
Also known as the “Wild Canary,” these birds don’t nest until weed seeds, typically thistle, appear, which happens about mid-summer. They are the latest nesters in North America, which is probably why they typically raise only 1 brood per year. The nest photos show their “signature” nest with thistle and cattail fluff woven into it.
The American Goldfinch eats only seeds and they start their babies out on a seed diet very early. This is quite rare among song birds.
We have quite a number at our house as they love, love, love the bird feeders we have up in the winter. By the time they change color to their beautiful yellow we have so many that it’s like Easter eggs all over the yard.
We see V-shaped flocks flying over in fall, alerting us to the change of seasons. We have had one roam about for a couple of years but was probably nesting across the highway in the wetland area.
It was a beautiful late November day when we heard the flock fly over our property. They have such a unique sound as they honk each other forward; they were on their way to warmer climates!
We have this beauties at our feeder in late winter/early spring as they arrive. We don't feed during the summer months so they soon head for the leafy trees, which makes it much harder to see them. The females are similar looking to sparrows. These birds enjoy berries, especially the mulberries that we have around the property.
Also known as the Gray Ghost because of its feather coloring. It is the only one of this genus that is found on every continent, except Antarctica. Harriers have keener hearing than other hawks and hunt by flying low to the ground making a surprise attack on their prey. When you see them they are usually operating on powered flight (vs gliding); they rely on this more than other raptors. In flight, their “lazy, loping” wingbeat is a good way to recognize them.
The genus name Circus is derived from Ancient Greek kirkos, meaning 'circle', referring to a bird of prey named for its circling flight.
An accipiter, Cooper's hawks are truly the reason people call them "bird feeders" as they not only feed the little birds but Cooper's hawks are notorious for hanging around feeders for their food...the little birds!! These hawks are quick and agile, making them ideal for hunting in urban areas.
Cooper's hawks were once threatened with extinction because of DDT. Like the eagles, their eggshells were so thin they could not sustain a baby bird's development.
The most common and widespread of the buteos. I can spend hours watching these guys hunt. It's quite interesting!
One of the largest hawks. Their favorite food consists of voles and lemmings. We often see them in the winter hunting the prairies from the top of the kestrel house.
We don't have a pond but at least once a year, we have a great blue heron fly over. These are the largest and heaviest herons as well as the most vocal. They are solitary and nocturnal although you can spot these around ponds during the day.
These are the only birds that can fly backwards and hover like insects. When they fly into the feeder, the buzz of their wings is fairly loud, like a HUGE bumblebee. If they are stressed or crabbing at another bird, the sound is tiny little squeaks. When I first heard it I thought there was a rodent around!
One of their preferred foods are spiders, but unfortunately, hummingbirds can get trapped in the web and eaten. I suppose this would have to happen occasionally since the hummingbird is searching for spiders. It’s an eat or be eaten world! Our hummies come around the nectar feeder more often at dusk; I’ve since learned this is the case for most hummies. They need this additional boost to get thru the night.
There are lots of hummingbird organizations doing great work on behalf of these little birds:
Hummingbird Monitoring Network is a science-based, project-driven, nonprofit organization dedicated to the conservation of hummingbird diversity and abundance throughout the Americas.
The Hummingbird Society was founded by 1996 with the goals of teaching about hummingbirds and working to prevent their extinction.
Hummingbirds.net is a place to learn about attracting, watching, feeding, and studying the hummingbirds that breed in North America.)
These are considered beneficial bird to farmers because they eat insects and weed seeds. We see the indigo buntings hanging out on the “edges”—edge of the prairies, edge of the woods, etc. I’ve come to learn that they prefer this type of cleared areas, much like eastern bluebirds.
A very common winter bird that loves to feed at ground feeders and forage at the base of trees and shrubs. Flocks tend to stay together and return to the same location from year to year.
Also became known as the “Sparrow Hawk” because it would eat House Sparrows in urban areas. The female incubates the eggs and the male feeds them. When he has food, he calls and the female flies from the nest to meet him.
Most falcons are bird hunters but kestrels are a bit different and prefer small rodents. This difference also accounts for why they look at act a bit differently than other falcons. One interesting behavior is called “kiting.” This is where they hover with their wing flapping in one spot. This is hunting behavior and once they see their prey, they can drop and attack easily.
In 2009, Hawk Watch International has sited a study stating that the kestrel is in decline. It was based on migration counts so the reason why is not fully known. They suspect it is because of one or more of the following factors:
- poisoning by pesticides in agricultural areas
- predation by increasing populations of Cooper’s Hawks (Accipiter cooperii)
- development and reforestation of preferred habitats
- potential exposure to the West Nile virus
If you have kestrels in your area and would like to participate in data collection, check out the American Kestrel Partnership
These birds lay their eggs in indentation on the ground that they make with their bellies. It's amazing how the nest and eggs are so well camouflaged that they disappear.
These are one of the birds known for the "aerial hawking," a hunting behavior that begins from a perch. They fly out, get the prey in midair, and circle back to the perch. Eastern kingbirds are named for their aggressive nature when defending their territory.
These little birds will migrate with other warblers and insect-eating songbirds. Their preferred habitat is coniferous trees.
Females quack while males do not.
Mallards have complex courting behavior, which is displayed in fall.
Eastern and western meadowlarks look very similar and the only way to differentiate them is the song.
All bird's feathers are amazing. Meadowlark feather appear dull brown but over the winter, that color rubs off, showing the beautiful yellow!
These birds are not hawks although they do “hawk,” which means catching insects in flight. They eat copious numbers of insects; analysis has shown that 1 bird at 500 mosquitoes while another ate 2,175 flying ants. They have long bristles on their face, which act as insect catchers. These facial "feathers" also have sensory functions much like cat's whiskers do.
Their main winter food is conifer seeds and in bad years, it can move southerly. These birds feed by moving up and down a tree foraging in the crevices.
AKA Devil downhead, Tree mouse
The word "nuthatch" came from Europe and refers to their foraging technique. Nuthatches are among the few birds known to use tools. Some hold a piece of bark to uncover insects.
These beautiful birds got their name from Lord Baltimore. This family was business owners in colonial Maryland and they had orange and black in their coat of arms. This brilliant orange isn't seen in the males until the 2nd year when it's time to attract a mate. Orioles do not reuse their nests but they may take the material from an old one to create a new one.
Orioles eat insects throughout the year and they love sipping nectar from flowers and hummingbird feeders. In place of nectar, we feed them watered down jelly and oranges. They are important predators of tent caterpillars.
Baltimore orioles are one of the first birds to begin migration, which mostly takes place at night.
We love that these orioles come to spend the summer with us! They usually arrive about the same time the Baltimore orioles do.
We hear these owls singing their "who cooks for you" song most nights. It's nice to hear them calling to each other.
All owls are incredibly quiet when they fly. This is because their feathers have features that disperse the sound of the air movement, muffling the flapping of their wings.
The “Great Silent Hunter” is found in a diversity of habitats and they are permanent residents. As with all species, the younger ones will move about until they find and establish their territories; owlets leave their nest at 10 months. Unique to these are that they are the earliest nesting of our owls and they have the ability to fly silently, hence earning its nickname.
These migrant flycatchers love hanging out in our woods and singing Pee-ah-wee!! I'm happy to have them as they eat insects. If you watch them long enough, you'll notice they sally back and forth to the same favorite perch. You might notice they have a couple of favorites but the habit of going back to the same perch is unique.
Pewees have super long wings and super short legs!
Ringed-neck pheasants have a hard time making it through the winter around here. They are omnivorous and opportunistic with their feeding and will come to bird feeders, which you'd think would keep them healthy through the winter, yet many of them cannot survive our cold Wisconsin winters.
Eastern phoebes are in the flycatcher family meaning they eat mostly insects but occasionally they will also eat berries. This is thought to be the first bird ever banded by Audubon in 1840.
Flocks of these little birds will shake and tear at prairie plants then rush to the ground to eat the seeds. In winter, they love birch seeds.
These guys are thought to be the harbingers of spring but often they will hang around through winter. When they do come back, it is such an awesome sight to see the multitudes of robins hopping around the yard. Seeing them means I have worms and worms in the soil is a good, no, it’s a great, thing!!!!
Shrikes like to cache their food. They bite their necks to kill them, then impale them on a thorn or barbed wire. They earned the nickname “butcherbirds” for this practice. Shrikes are very cunning and will typically hunt from perches but they will also groundhop, hover, and flycatch. Some will resort to mimicry. Shrikes are a good indicator of quality habitat, so again, we were SUPER excited to have this guy around!
Field sparrows breed in old fields or prairies that have woody and/or shrubby areas (not woods or forest) nearby or tall grasses near a fenceline. They will sing all day long when breeding.
These are seen in the winter flitting around the prairie and are especially prevalent during the Christmas Bird Count.
Also called the “Hairbird” because it loves to line its nest with hair. Before the advent of cars, they got their hair from horses, but now they will pluck the fur from a sleeping dog!
These guys love hanging around golf courses. So appropro, huh!! Get it....CHIPPING sparrow!
These sparrows like brushy areas and thickets. According to Cornell, “Clay-colored Sparrow young leave the nest before they can fly. They hop to the ground from their nest in a shrub and run an average of 40 feet to seek cover in a thicket, where their parents will continue to feed them. They won’t fly for the first time for another 6 to 8 days.”
I do like the LBJs (Little Brown Jobs), but this one...not so much. They take over the bluebird boxes and act much like an invasive week in the prairie. We didn’t see one until 2013 and frankly, we would prefer they stayed in urban areas.
To avoid danger, this sparrow doesn’t immediately fly but rather runs along the ground. When it does fly, it flies low, barely over the tops of plants.
A very melodious bird that sings persistently during breeding season and is quite territorial.
Much of what is known about the physiology of bird migration has been learned from this species.
In 1890, 100 birds were released in New York City. They have easily adapted and congregate in roosts of tens of thousands. In the winter, it is common to see telephone lines thick with birds sitting side by side. While they compete with native birds for nest holes and food, they do provide benefit by eating great numbers of insects.
This swallow migrates great distances with some wintering as far as Argentina. When feeding young, they are estimated to cover 600 miles a day in search of food.
This is the only swallow that winters in Wisconsin. They like the use the bluebird boxes on our bluebird trail. They are beautifully iridescent with what I call a "liquid warble" song.
They fill their nests with various feathers that they find around. It's a nice surprise to discover some of the types of birds in the area via their feathers. In 2013, we learned we had wood ducks around!!
Scarlet Tanagers are secretive and mostly heard rather than seen. They prefer to live in forests but I had the pleasure of seeing one fly from our woods across the prairie to the other woods and occasionally we can listen to their "chick-bur" in the mornings. They prefer wasps, bees, caterpillars, moths, and beetles for food.
Males molt into yellow feathers when it is not breeding season. Without knowing this, it would be difficult to ID one of these beauties!
In 2014, I saw 2 male Scarlet Tanagers and 1 female looking for food along the edge of our Deer Camp Prairie.
One of my favorites with its repertoire of 2,400+ songs! Even with that many tunes to listen to, it’s easy to ID these birds from their songs because they sing them in pairs.
These are rather shy birds, hanging out at the edge of a wooded or shrubby area and flitting out for insects.
This bird has the most beautiful, flutey song. They are rather illusive, making photos of them difficult to get.
One doesn't see these birds often but you can hear them, not only their song but their scritching on the ground.
These very loud little birds share a unique characteristic with the Chickadee -- they cache their food and as such their brains (mainly their hippocampus) enlarge during the autumn and winter months. These birds are often heard and not seen but sometimes I caught glimpses of them in roadside bushes in the winter.
The Wild Turkey was nearly extinct by the end of the 1900s because of over hunting. In 1950s, there were about 500,000; today there are 6.8 million in North America. Turkeys can fly and glide up to a mile and they can swim easily but are rarely seen in water.
We never tire of seeing "our" turkeys!! One day we saw a few cross the road. We watched for a while and eventually started counting as the line seemed to not end -- 75 was total -- the largest group we've counted to date.
Turkeys are beautiful birds. We had one we called the "Monster Turkey." He was nearly 5' long and weighed 30-35#!!
A persistent singer, they may sing while capturing large insects. We love being serenaded by them while we're working in the woods!
Hangs out at the top of the canopy and is hard to see. Another one that sings to us while we work.
Turkey vultures locate carrion by their acute sense of smell. They do a great clean up service for our earth. But they lack the ability to screech because they have no syrinx. So, when they are stressed, their head pales from its “normal” redness. This nonverbal method is their way to convey warning to others.
The featherless head of the turkey vulture is a great design! Not have feathers means they don't have to worry about bacteria, parasites, and disease as their head stays clean when they are eating carrion.
Turkey vultures have communal roosts. These serve several functions, one of which is for young birds to learn from the older, more experienced birds.
Often parasitized by cowbirds, the yellow warbler has found a way around this by burying the cowbird egg and sometimes their own under another nest layer. Sometimes a nest can be found with up to 6 layers, each with a cowbird in it.
Feeds by picking insects from bark crevices. Sometimes will come to bird feeders. Singing is usually done from the canopy of the trees.
This warbler, also called a Butter Butt, is usually the first warbler seen in spring.
This warbler isn't common in the Great Lakes region so we feel pretty honored to have him visit us. He feeds much like a nuthatch and uses its long bill to get insects from pine cones. I remember him by thinking of the Lone Ranger!
Woodcocks mainly eat earthworms. The tip of their bill is flexible so they can grasp the worm while probing. We had a number of them stop by in 2010 and PEENT for us and give some great aerial displays. They would fly over the deck, making it very easy to see their silhouette. See my blog post for more information.
The smallest and tamest of the eastern woodpeckers. These are very similar looking to hairy woodpeckers. I've learned to differentiate them by the size of their bills.
Slightly larger than the Downy, this guy hangs out mostly in the woods and is a bit shyer than the Downy although we see him at our feeder quite often.
Also known as a “Logcock,” this elusive woodpecker is found mostly in woods. We refer to him as the Jungle Bird because of his call. It is easily mistaken with the Flicker's call so listen carefully!
Woodpeckers are very beneficial to our woods and forests. They consume large numbers of wood-boring beetles and other pests.
The red-headed woodpecker is a bird of Special Concern in Wisconsin. Their habitat is being destroyed or allowed to degrade at faster rates than the bird can reproduce. They prefer open woodlands and oak savannas.
Wherever savannas are and beavers, you could find these birds. They love to be where standing dead trees are found. This is partially because they are ravenous insectivores, eating more insects that other North American woodpeckers! They are known to eat eggs and nestlings of other birds as well.
Males and females look alike. They equally defend the nest and they both feed the young. Most of their nests are from used flicker excavations.
These little birds have a BIG voice!! We like having them around but not too close to the bluebird houses. They do not get along with bluebirds and will attack the babies and kill them.
They can create up to 6 nests in their territory and they will defend these against any other bird.