Articles about the various state barn owl populations with discussions on conservation and use in agriculture.

MARK BROWNING

North Carolina Barn Owls

Barn Owls in North Carolina

North Carolina is an important state for barn owls

North Carolina is an important state for barn owls

In addition to having its own populations of barn owls, North Carolina is an extremely important state for barn owls dispersing from the north. It is the first state after the high mountains that northern birds reach after traversing the mountain forests with dramatic flights and large expenditures of energy. Our satellite tracking study showed that a high percentage of young barn owls in the northeast fly south over the Allegheny Mountains, often flying as much as two hundred miles over four nights to cross onto the lower elevations of the Carolinas.

After the heavily forested mountains that afford poor hunting, North Carolina provides good habitat for birds that may need to replenish their energy with prey. All seven birds from our study that flew south crossed into North Carolina. The same is likely true for those many barn owls that fly over migration points such as Cape May, New Jersey. Some of these birds likely overwinter in the state.

 North Carolina Barn Owl Populations

North Carolina Barn Owl Map (credit Carolina Bird Club)

North Carolina Barn Owl Map (credit Carolina Bird Club)

North Carolina once had excellent populations of resident barn owls and good populations remain in certain areas. But human development, a decline in the number of farms and old barns, and the switch from hay and cattle to soy and corn has taken away habitat for barn owls. Today, the highest concentrations of barn owls are likely along the coastal region. A second area of high concentration is in the western-center of the state, where hay and cattle still predominate. Eastern counties that support high wheat production and large areas of salt-water marsh also harbor good populations. The only region where barn owls would be expected to be scarce would be the mountainous counties in the far western portion.

Since barn owls are very secretive and no comprehensive surveys have been done, the accompanying range map may underestimate populations of barn owls overall, however it provides a good indicator of relative abundance within the state.

Conservation Efforts by the New Hope Audubon Society

The New Hope Audubon Society is installing scores of barn owl nest boxes in good habitat

The New Hope Audubon Society is installing scores of barn owl nest boxes  in good habitat

In 2012, the New Hope Audubon Society began erecting nest boxes in what is known as the Triangle Area, in particular, Chatham, Orange, and Durham Counties. They have dubbed their efforts The Piedmont Barn Owl Initiative and they encourage residents to install nest boxes in these counties as well as Granville, Person, Guilford, and Randolph counties. They will actually donate excellent nest boxes to residents who own good habitat in their target counties of Chatham, Orange, and Durham. Contact them for more information.

 

 

 

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MARK BROWNING

Rhode Island Barn Owls

Barn Owls in Rhode Island

Barn owls exist along the coast and on islands off Rhode Island

Barn owls exist along the coast and on islands off Rhode Island

The first barn owl was recorded in Rhode Island in 1938. From then into the 1950’s it became fairly common throughout the coastal lowlands. Since then, in the face of intense development in those same areas, the barn owl has been nearly extirpated on the mainland where only widely scattered records are known. Almost all recent sightings have been within 5 miles of the coast. Two remaining populations exist on Aquidneck and Block Islands where farms still predominate and the owl is known to nest in abandoned buildings and dig its own burrows in sea cliffs.

Block Island and Wildlife Habitat Restoration

With only about 3500 acres of salt marsh and 65,000 acres of wetlands remaining, Rhode Island has lost approximately 35% of its wetlands. Despite ongoing losses of salt marsh, wetlands, and farmland, recent conservation efforts have restored salt marsh habitat on Block Island. Such conservation work is benefitting numerous bird species including the grasshopper sparrow, barn owl, northern harrier, and upland sandpiper. In 1998, the Partners program funded a saltmarsh restoration at Mosquito Beach, the largest producer of mosquitos on Block Island. Channels were dug to allow fish to swim farther into the saltmarsh, drastically reducing the mosquito production. Almost 13,000 acres have been targeted elsewhere as potential sites of freshwater wetlands restoration.

Rhode Island Agriculture

Yellow = good populations Blue = potential random breeding

Yellow = good populations
Blue = potential random breeding

About 60,000 acres of farmland are left in the state. Potatoes are the leading crop. Milk is second. However, Rhode Island is also home to numerous horse farms and, due to the small size of the state and the concentrated rural areas, the density of horses in RI may be one of the highest in the country. Because horses and cattle attract high numbers of rodents (house mice and Norwegian rats mainly), the potential for a win-win situation exists in such enterprises installing barn owl nest boxes. It could widen the distribution of barn owls in the state while helping livestock farmers lower pest damage.

 Barn Owl Conservation in Rhode Island

The barn owl could benefit from nest box programs near wetlands and salt marshes, and in rural areas that support horse, dairy, and hay farms. To report barn owl sightings or an interest in erecting barn owl nest boxes, contact: State Land Conservation and Acquisition Program, 235 Promenade Street, Providence, Rhode Island 02908 (401) 222-2776 x 4307

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MARK BROWNING

Louisiana Barn Owls

Barn owls thrive in Louisiana

Barn owls thrive in Louisiana

Barn Owls in Louisiana

Louisiana harbors excellent populations of barn owls. High numbers exist in the southern counties where sugar cane, rice fields, and marshlands dominate, in the northeastern rice growing areas, and along the Mississippi, Red, and Archafalaya river basins. Not so good for barn owls are cotton, soy, and corn, as well as the forests and silviculture in the northwestern third and northern panhandle, however nowhere do these crops dominate so greatly that other beneficial land uses such as hay, wheat, rice, horses and cattle do not help barn owls numbers. So the barn owl is present throughout the state.

 Barn Owls that Disperse from Northern States

From our satellite telemetry study, we know that Louisiana is an important state for young barn owls dispersing southward in the fall from farther north. Most young barn owls in northern states head southward, often traveling hundreds of miles to find wintering territory in the Gulf States. One of our barn owls, released in Pennsylvania, flew over the Alleghenies, through the Carolinas, then headed west to spend the winter along the shores of Lake Pontchartrain outside of New Orleans.

Louisiana Agriculture and Barn Owls

Rice fields can attract high barn owl numbers

Rice fields can attract high barn owl numbers

Sugar cane suffers high crop losses to astounding numbers of cotton rats that have a never ending supply of food in the cane; the same is true of rice fields in the NE and SW counties where marsh rice rats are the common pest. Barn owls can be induced to create dense populations in both crops. The only limiting factor to barn owl populations in these areas is the availability of suitable nest sites.

Barn Owl Prey in Louisiana

In a Louisiana coastal marsh, Jemison and Chabreck (1962) found that rice rats made up 97.5% of the prey of Common Barn-Owls. This will also hold true in rice fields. But in sugar cane, studies in Florida have shown cotton rats to dominate prey numbers. Around horse, cattle, and poultry farms, prey will likely be mostly house mice and Norwegian and black rats.

Distribution of Barn owls in Louisiana

Barn owls are most common in the south and northeast of LA

Barn owls are most common in the south and northeast of LA

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MARK BROWNING

Oregon Barn Owls

Barn Owls in Oregon

Oregon has good populations of barn owls

Oregon has good populations of barn owls

Distribution of the barn owl in Oregon is complex due to the presence of varied ecosystems. The Pacific Ocean moderates the coast and provides ample rainfall, and the Cascades Mountain Range that runs down through the western third divides the state. Generally, populations are very good in open areas west of the Cascades, with dairy farms along the coast and a rich agricultural valley that stretches from Portland to Eugene in the south. East of the Cascades, barn owls are found in good numbers in the northern regions where wheat and barley farms thrive. Southward, the remainder of the state holds moderate to low numbers of barn owls in the cattle raising counties. The barn owl is present everywhere except in forested regions and at altitudes higher than 6000 feet.

The Oregon Department of Fish and Wildlife says: “The Barn owl is a fairly common permanent resident in open country west of the Cascades. East of the Cascades it is more local in its distribution being most common in agricultural areas.”

Voles (meadow mice, genus Microtus) are the most common prey, however in some areas, the pocket gopher may predominate. In one pellet analysis study of 825 pellets, voles comprised 64% of prey items, with deer mice, pocket gophers, shrews, house mice, and small birds comprising the remainder. 

Red = Excellent Orange = Good Yellow = Poor to Fair

Red = Excellent
Orange = Good
Yellow = Poor to Fair

Voles are particularly destructive in agriculture, especially because of their high reproductive rate. Females born today can begin mating within a month. Voles damage roots, consume fruit, and even girdle vines and fruit bearing trees by chewing the bark near the ground.

Barn owls are being used for rodent control by both grape and blueberry growers in Oregon. The apple, pear, plum, and cherry orchards are excellent candidates for barn owl programs.

 

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MARK BROWNING

Colorado Barn Owls

Barn owls are common in Colorado

Barn owls are common in areas of Colorado

Barn Owls in Colorado

Barn owl numbers are good in the prairies and grasslands of eastern Colorado and in the valleys and scrub lands of the western part of the state. They nest in cottonwoods, hay bales, riverbanks, culverts, old mines, and even excavate their own nesting burrows in sandstone cliffs. They do well near fields of alfalfa and row crops as well as on the grassy plateaus at 5000 to 6500 feet. The central part of the state is dominated by the Rocky Mountains where barn owls are rare to nonexistent. Open field hunters, barn owls typically avoid forested areas and high altitudes.

Barn Owl Prey in Colorado

ORANGE = GOOD POPULATIONS OF BARN OWLS IN COLORADO

Barn owls are common in eastern Colorado and in the western valleys (Orange areas)

As in many arid western states, the kangaroo rat, an inhabitant of dry scrub and desert, is an important prey. Named for their habit of hopping along on their two hind legs, kangaroo rats are natural denizens of arid areas and provide a staple food for barn owl populations. However, in the agricultural areas, with large orchards of peaches and apples, barn owls concentrate on vole and gopher populations that are always attracted to fruit farms. Cattle remains Colorado’s largest agricultural enterprise, and on cattle farms, barn owls will likely find house mice and Norwegian rats to be the most common prey.

Barn Owls Digging their own Burrows

It was in New Mexico in 1973 when a researcher (Martin) witnessed barn owls excavating their own nesting burrow in an arroyo wall. Later, in 1978, two researchers (Millsap and Millsap), conducted more extensive research on this phenomenon in Colorado. They found that barn owls preferred to dig their own burrows over occupying already existing nest boxes even though it took a lot more effort. Burrows were typically dug directly into the hillside ending in a round hollow where the eggs were laid. Burrows took between five and nine nights to excavate. The researchers concluded that the burrows into the earth provided a survival advantage over other types of nest sites: they were cooler during the heat of the day, and provided more protection from predators.

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MARK BROWNING

Kansas Barn Owls

Barn Owls in Kansas

Kansas grasslands provide excellent barn owl habitat

Kansas grasslands provide excellent barn owl habitat

Kansas has abundant good habitat for barn owls including prairie, pasture, hayfields, river valleys, and scrublands, all with good supplies of food in the form of voles, mice, and kangaroo rats. Barn owls are present in every county, and anywhere they can find barns, outbuildings, abandoned houses, holes in cliffs, and nest boxes, they colonize very quickly. The main problem in Kansas is that suitable nesting sites in much of this good habitat are very scarce. Grasslands and hayfields stretch for miles without good nesting places.

Residents who put up nest boxes are often rewarded very quickly by barn owls taking up residence.

Barn owls both find and dig nest holes along the Cimarron River

Barn owls both find and dig nest holes along the Cimarron River

Max Thompson, a well-known birder and author of bird books of Kansas, agrees that a lack of nesting sites keeps barn owl populations lower than they could be. He does say that barn owls are common along the Cimarron River in the southwestern part of the state, particularly Morton County, where they find or even dig hollows in the clay and rock banks. This would indicate that anywhere in Kansas where high banks or cliffs border river valleys, barn owls will be present in good numbers. Both the Cimarron and the Arkansas River systems are comprised of many such tributaries.

Likewise, nest boxes should meet with good success in the state, since barn owls are always on the lookout for suitable breeding sites.

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MARK BROWNING

Idaho Barn Owls

Barn owl nests in the cliffs along the Snake River are common

Barn owl nests in the cliffs along the Snake River are common

Barn Owls in Idaho

As our range map shows, barn owl populations in the southern half of Idaho are excellent from the agricultural valleys to the high desert scrublands; the northern half is too heavily forested for barn owls except for certain lower altitude valleys in the west.

Biologist Bruce Haak of the Idaho Department of Fish and Game cites the existence of thousands of miles of river cliffs, such as those along the Snake River, where barn owls find abundant crevices and holes in lava, sandstone, and clay for nesting. In the agricultural valleys of orchards, crops, wheat, and irrigated hay, he says they breed in barns, silos, and other outbuildings. The desert scrub provides high numbers of rodents, including kangaroo rats; the farm lands produce rich supplies of voles and pocket gophers.

Road deaths of barn owls on Idaho highways have drawn a lot of attention. Jim Belthoff, biology professor at Boise,

Barn owls ready to fledge

Barn owls ready to fledge

has estimated that a few thousand barn owls die each year on roads in the state. Despite these high numbers, it must be kept in mind that the presence of so many barn owls (of which a percentage do succumb to being hit by vehicles) is actually a sign of a very healthy barn owl population in the surrounding countryside. Barn owls produce large numbers of young to offset high mortality (as much as 75% in the first year), and there are no signs that road deaths are adversely effecting barn owl numbers in the state. One of the main reasons that barn owls get hit so often is that they are edge hunters, and the roads provide just such an edge.

Idaho contains excellent numbers of barn owls in the southern half

Idaho contains excellent numbers of barn owls in the southern half

A large pellet study revealed that barn owls in Idaho prey heavily on voles (meadow mice), however this will vary depending on the specific area. Where pocket gophers or kangaroo rats predominate, they will likely predominate in the owl diet.

Farmers of blueberries, grapes, apples, and other crops are using barn owls in nest box programs in Idaho to help suppress rodent pests.

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MARK BROWNING

Wisconsin Barn Owls

Barn Owls in Wisconsin

Wisconsin grasslands

Wisconsin grasslands provide excellent barn owl habitat

The barn owl in Wisconsin is rare and listed as endangered. Most breeding records have come from the southern counties where the state Bureau of Endangered Resources has attempted to bolster barn owl populations over the years by installing over one hundred nest boxes and releasing captive bred owls. The Wisconsin Department of Natural Resources in recent years has also installed a number of nest boxes.

Although natural grasslands and wetlands have declined in the state and been replaced by row crops such as soy, there are plenty of pastures and meadows remaining throughout the state. A main limiting factor is the severe winters, particularly the heavy snowfalls that regularly occur, making it difficult if not impossible for barn owls to catch prey beneath the snow. Mild winters allow barn owl populations to grow, but a single heavy snowfall that lasts over a week on the ground can severely set back barn owl numbers.

Nonetheless, barn owls do breed each year in the state and nest box programs have had some success. The range map is from the Natural Heritage Inventory Base in 2012 and shows counties of confirmed nesting. Keep in mind that such records are dependent on field work which is often limited and that barn owls can be very difficult to detect since they are secretive and nocturnal. Chances are that there are more barn owls than found and that other counties may harbor them. Residents in these or neighboring counties who live in good habitat such as grasslands, wetlands, or pasture would be helping conservation efforts by installing nest boxes and contacting their local DNR office when barn owls are seen.

Barn Owl Breed and Release Program in Wisconsin

The state of Wisconsin conducted captive breeding program and released 98 young birds into the wild between 1982 and 1987. This program was discontinued since there was no apparent increase in barn owls in the wild. This is typical of such barn owl breed and release programs – due to dramatic dispersal of young in the fall, high mortality, and low returns to natal areas, barn owls are not a suitable species for breed and release. Habitat enhancement, such as nest box programs, have proven to be far more effective.

Barn Owl Diet and Nesting in Wisconsin

Barn owls in Wisconsin feed mainly on voles (meadow mice) and shrews. They nest in silos, barns, outbuildings, tree cavities, and nest boxes. They breed March through July, laying three to nine eggs, with four or five on average. Researchers believe that most Wisconsin barn owls leave for the winter, but there are records of overwintering as well. It may be the young that disperse in the fall, and the adults that stay as in many other states.

An excellent large paper on the barn owl in general, with Wisconsin as a subset focus: http://dnr.wi.gov/org/land/er/publications/reports/pdfs/ER_report037.pdf

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MARK BROWNING

Connecticut Barn Owls

Barn Owls in Connecticut

Barn owls are rare in Connecticut

Barn owls are rare in Connecticut

Barn owls have always been uncommon to rare in Connecticut due to the state’s harsh winters. They are principally found along the coast and within the large river valleys of the state. Breeding has been confirmed in coastal areas and near Middletown, 30 miles in from the coast, where there is an active monitoring and nest box program. The already low Connecticut population is declining from habitat loss as reforestation encroaches on grasslands and the numbers of small farms dwindle. Biologist Laura Saucier, who monitors barn owls for the state, says that they typically find less than five occurrences each season and that most nests are within a few miles of the coast. That said, there are always more barn owls than detected, and the fact that Middletown, near the center of the state, hosts barn owls, raises the possibility that others exist in counties not being monitored.

History of the barn owl in Connecticut: The barn owl has always occurred in low numbers in Connecticut due to the state’s northern latitude and deep winter snows which prevent the owls from grabbing their prey beneath the surface. Historic records from the late 1800’s indicate the bird was considered a rare breeder in the state then, with records from coastal areas such as  Stratford, Madison, Stamford, Leesville, and New London County. But there were also inland sites along the Connecticut River such as Portland and East Hartford as well sites further west such as Litchfield and Winsted, where one pair in an abandoned factory produced 6 young in 1892 and 7 eggs in 1893. As low as the population was in the nineteenth century, it is undoubtedly lower today.

Barn owls are known to inhabit only near the coast and inland near Middletown

Barn owls are known to inhabit only near the coast and inland near Middletown (gray areas) in small numbers

Diet and Breeding in Connecticut

Barn owls eat mainly voles and shrews in Connecticut. Breeding occurs April through August.

Installing Barn Owl Nest Boxes in Connecticut

Nest boxes would best be installed within ten miles of the coast, or in the Middletown area where barn owls have been known to breed. Any sightings of barn owls should be reported to the state Department of Energy and Environmental Protection at 860-424-3000.

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MARK BROWNING

Tennessee Barn Owls

Barn Owls in Tennessee

Barn owls are doing well in Tennessee overall

Barn owls are doing well in Tennessee overall

The western third of the state, with its low-country riverine and wetland systems, provides excellent habitat; and hay production in a wide band in the eastern third also produces good numbers. The middle of the state, though high in hay production, does not receive as many reports of barn owls as the east. This may be due to changing farming practices in which the land is cleared and farmed more extensively. The mountainous areas of the far eastern sections hold lower numbers as well. Yet, barn owls are likely present in every county.

In the absence of any in-depth studies of the barn owl in Tennessee, and with some decline in hay production along with an increase in development, the barn owl has been designated as a species in need of management.

Wildlife rehabilitators report that most of their orphaned owls come from tree nests, but barns and silos still play a big part in providing nesting sites for these large cavity nesters. The barn owl eats mainly voles (meadow mice), deer mice, and shrews in Tennessee. Nesting season begins as early as late March and extends through July. Three to seven eggs are laid normally.

Tennessee hayfields provide excellent barn owl habitat

Tennessee hayfields provide excellent barn owl habitat

Randy Whitworth, a wildlife rehabilitator at Henry Horton State Park in Marshal County, tells an interesting barn owl story. Since he gets barred, screech, great horned, and barn owls in that order, he had always assumed that barn owls were scarce in his area. In response to a call about baby owls, he went out to rescue six young barn owls that had emerged from a split oak, drove them ten miles back to his house, and placed them in a cage on his porch. Looking out the window later, his wife said she thought the barn owls were out of the cage. He went out to find four adult barn owls flying down to view the babies. That indicated to him that there were more around than he thought.

Orange = good pop. Yellow = fair pop.

TENNESSEE RANGE MAP AND RELATIVE ABUNDANCE OF BARN OWLS Orange = Good populations Yellow = Fair populations

Tennessee biologists encourage residents to erect barn owl nest boxes. Any county in Tennessee would be suitable. Anyone who does install a nest box and gets barn owls should alert their local DNR office.

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MARK BROWNING

Indiana Barn Owls

 

Barn owls once thrived in Indiana

Barn owls once thrived in Indiana

As in many northern states, in the late nineteenth and early twentieth centuries, when the original forest cover was cut in Indiana to create land for farming, the barn owl thrived. Since then, much of Indiana’s forests have regenerated and farming has moved from hay and cattle to soy and corn. These and other factors, such as the advent of metal barns which afford no access, have caused barn owls in Indiana to plummet.

Southern Indiana counties along the Ohio River have good barn owl populations

Southern Indiana counties along the Ohio River have good barn owl populations

“Although the Barn owl is endangered in Indiana,” says John Castrale, Nongame Bird Biologist with the Indiana Division of Fish and Wildlife, “the Indiana population is low but stable. Approximately 25 pairs are found each year, maybe 50 over exist over the entire state, mostly scattered along the Ohio River counties in pastures and mixed habitat of southern Indiana farm country.” In contrast, the central and northeastern regions, dominated by the vast Corn Belt, provide poor habitat. As with barn owl populations in neighboring Illinois, most confirmed presence has been in the southern third where there is mixed woodland, pasture, and hay.

Another excellent habitat happens to be, ironically, the thousands of acres of wild grasslands that have grown on top of areas that have been strip mined. Indiana Fish and Wildlife has begun erecting nest boxes in such areas.

Records of barn owl breeding sites in Indiana

Records of barn owl breeding sites in Indiana

Barn owls in Indiana eat primarily voles (meadow mice) and shrews. They may breed in any month of the year surprisingly, even in winter, but their primary breeding season is April through July. They nest in any available hollow, including barns, hay sheds, abandoned buildings, grain bins, and tree cavities.

Since 1984, the Non-game and Endangered Wildlife Division of the state’s Department of Natural Resources has been monitoring nest sites and has erected more than 200 boxes, some of which have attracted additional breeding pairs. The state encourages nest box installation near good habitat.If you see a barn owl in Indiana, or are interested in erecting a box on your property, contact the Indiana Division of Fish and Wildlife at 812-849-4586.

 

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MARK BROWNING

Iowa Barn Owls

Barn Owls in Iowa

barn_owl-flying-rodent

Barn owls eat mostly meadow mice (voles) in Iowa

Iowa once had far more barn owls than it does today, though the numbers in Iowa were never very high due to the normally severe winters. The main problem for barn owls is not so much cold as it is deep snow. When a heavy snow remains on the ground for more than a week, many barn owls succumb. Even so, the numbers of barn owls present in the state have declined as good habitat has disappeared.

 Today, Bruce Ehresman, Iowa DNR Wildlife Diversity Program says that the state usually locates around twelve nests per year, so there are probably a number that they do not find. Most nests are found in southern and southwestern Iowa.

Iowa Prairie

Iowa Prairie is good habitat for barn owls

 Iowa has lost 90% of its original 4.5 million acres of wetlands to farm conversion. Prairie has also seen similar losses. But today, Iowans are restoring wetlands and prairie. Farmers are creating 10,000 acres of wetlands under the federal Conservation Reserve Program, and another 91,000 acres are being created by the North American Waterfowl Management Plan and the federal Wetlands Reserve Program. Prairie too is being restored.

All of this bodes well for the barn owl in Iowa where efforts to help this beautiful bird have been in place since the 1980’s when the state attempted breeding and releasing 400 young owls in good habitat. Biologists placed radio transmitters on 36 released owls in 1985. Twenty-four of the birds perished in the first 60 days, and thirteen of them appeared to have been killed by great horned owls.

Without evidence that the program increased barn owl numbers, the IDNR finally ended the captive breeding program. They shifted the program’s emphasis from stocking birds to placement of secure nesting boxes in areas where owls have been seen. Most of the boxes are placed in old barns surrounded by extensive CRP grasslands.

Old barns near extensive grasslands could be a key to survival of the species in Iowa. State biologists encourage residents to install nest boxes in good habitat and to report any sightings and more interested yet in possible nesting attempts. The IDNR can be reached by calling 515-432-2823.

 

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