Barn Owls in Oklahoma

Barn_Owl_Flying_8349Barn owls were once very common in much of Oklahoma which harbored huge areas of natural grasslands. They are still particularly abundant in the panhandle of the northwest dominated by short grass prairie, and the southwest with its mix of mesquite grassland and mixed-grass plains. The northeast, west-central, and southern regions have good to fair populations in tallgrass prairie broken up by stretches of oak forest. However, these grasslands have recently begun to be overgrazed by cattle and planted with row crops, reducing barn owl numbers. Barn owls are rare or absent in the far eastern part of the state where oak-hickory forests and oak-pine forests dominate.

With almost three million acres of hay, and over five million head of cattle, Oklahoma provides expansive additional habitat for barn owls in the form of cultivation and pasture as long as overgrazing does not occur. The eastern third of the state is riddled with rivers and large bodies of water, and wetlands are widespread in the southeast and east central parts of the state.

With all of these attributes, Oklahoma still has seen a decline in barn owls in many areas. Researcher Steven Sheffield of the University of Oklahoma

Dark blue = abundant; Light blue = good; Green = poor; Gray = rare to absent

Dark blue = abundant; Light blue = good; Green = poor; Gray = rare to absent

points out that the barn owl was once the most abundant raptor in north-central Oklahoma, but that is no longer true. Since rodents have remained abundant, the issue appears to be lack of nesting sites, a common problem in grasslands. Combine this with the continuing loss of old buildings for nesting, the switch from wooden to metal barns, and the cutting down of dead trees, the barn owl in Oklahoma appears poised to benefit from nest box programs.

The University of Central Oklahoma analyzed 47,000 Barn Owl that revealed Oklahoma barn owls feed primarily on the Hispid Cotton Rat, followed by Deer Mice, and Ord’s Kangaroo Rat. It will breed in cisterns, church steeples, self-dug burrows in river banks, cliffs, caves, tree cavities and of course barn lofts and other outbuildings.

Thanks to biologists Doug Wood and Steven Sheffield for their contributions to the information on barn owls in Oklahoma.

Barn Owls in Utah

Barn_Owl_Flying_8349Utah is one of those states where extensive research has been conducted on barn owls. Researchers Dwight Smith and Carl Marti conducted a number of studies in the state. It was Smith who famously discovered a colony of barn owls in the buildings of an abandoned steel mill near Overton in 1968. Eventually this colony numbered 38 individuals before the mill was torn down. This was one of the first records of a dense breeding colony in the United States.

Essentially, the barn owl is quite common throughout Utah except in the forests, high mountains, and

Washington County farmland in Utah has excellent barn owl populations

Washington County farmland in Utah has excellent barn owl populations

the Great Basin desert in the western side of the state where they are likely rare. They are particularly common in the agricultural valleys. Smith and Marti found two excellent barn owl populations, a northern population that stretched from Utah County to Box Elder County and a southern population in Iron and Washington counties. Tony Wright, former Utah biologist who worked in southeastern Utah states that the barn owl is also common there. He reports that they are often hit by automobiles in that area due to their low flight pattern while hunting.

Old buildings, decayed cottonwoods, and self-dug burrows in the sides of arroyos are the most common nesting sites. The most common prey items found through pellet analyses are the meadow vole and mountain vole, followed by house mice, deer mice, and vagrant shrews.

Barn owls in Utah are common in many areas

Dark blue = common; Light blue = fair

Courtship runs from mid-January through March 1968. Eggs are laid as early as February but as late as April. The first hatchings occur in early March and the first fledglings leave the nests in mid-May. Fall nesting also occurs, though not as commonly. Usually incubation begins in early September with fledglings appearing in early December.

The agriculture of Utah plays an important role in sustaining healthy barn owls populations. Wheat, barley, and oats, poultry, and cattle are raised in almost every county.

An excellent paper on Utah barn owls can be found here: https://sora.unm.edu/sites/default/files/journals/jrr/v010n02/p00033-p00044.pdf

 

Barn Owls in New Jersey

Barn_Owl_Flying_8349New Jersey barn owls have experienced the most recent downturn of any population in the United States. Unlike so many eastern states where barn owls declined dramatically by the 1960’s, as late as the 1990’s barn owls were being found in very good numbers in the farmlands of New Jersey. Naturalist Leonard Soucy Jr. conducted a fifteen year study there, finding barn owl nests under bridges, in bell towers, warehouses, chimneys, and barns, with many nests in urban areas, and concluded that the New Jersey barn owl population was one of the most abundant populations in the nation.

Since then the barn owl has declined precipitously inland where much of New Jersey’s farmland with cattle and hay has been converted to housing tracts, lawns, shopping malls, and roads with a devastating effect on barn owl numbers. Today, barn owls are very rare there where they once thrived.

The Barn Owl Research Foundation Project

The bright spot in the New Jersey barn owl population is the excellent and stable habitat provided by the wetlands along the Delaware River in the southern portion of the state. Here, for over 30 years, researchers Bruce Colvin and Paul Hegdal of the Barn Owl Research Foundation have been installing and maintaining nest boxes in prime habitat and chronicling the year to year fluctuations in barn owl numbers and breeding success. Their work shows that barn owl numbers rise and fall annually according to a number of factors, not the least of which are the severity of the previous winter and the availability of small mammal prey.

Their study is one of the longest running and intensive studies of a barn owl population in the country and has resulted in adding valuable

New Jersey marshes, especially those along the Delaware River provide excellent barn owl habitat

New Jersey marshes, especially those along the Delaware River provide excellent barn owl habitat

information on barn owl population dynamics. In 2015, out of 39 nest boxes near marshes along the Delaware River, 16 nest boxes fledged young. That year, 65 chicks were banded, and to give an idea as to how the population’s breeding output fluctuates, the number of chicks banded between 2009 and 2014 ranged between a low of 68 in 2013 to a high of 155 in 2009. The recognition of natural swings in barn owl populations is significant: often, researchers will conclude that barn owl populations are declining when instead they are merely seeing short term fluctuations.

In addition to the populations along the marshes, there is some evidence that barn owls are breeding in some numbers in abandoned buildings near the coast in northeastern New Jersey but little monitoring of this population has been done.

In summary, even though barn owls may continue to be present throughout the state in scattered and low numbers, most of the breeding population is concentrated along the southern coast in Salem and Cumberland counties. This population continues to be stable, in large part due to nest box installation and maintenance.

Diet, Fall Nesting, and Other Findings

Prey consumption studies show that the meadow vole comprises a large percentage of the diet in New Jersey. A few fall nests have been observed but it should be noted that such nests suffer higher failure than those nesting attempts made in the spring. One important finding from the Colvin/Hegdal study was that they have found a fairly high number of previous year fledglings breeding in their natal area. Out of 22 adults captured in 2015, 6 (27%) had been banded in the study area in previous years. This shows that local populations, at least on the east coast, can recruit future breeding birds from their own fledglings.

 

Barn Owls in New Mexico

Barn owBarn-Owl-Box-1l distribution in New Mexico is defined by altitude—the mountains exclude barn owls– but excellent populations exist in the eastern third with over one million acres of farmland, the southwestern corner with lots of agriculture, and a central corridor of farmland formed by the mid-central Arizona New Mexico Plateau, extending from southern Sandoval County southward. San Juan County in the far northwestern corner also provides prime habitat where the southernmost portion of the Colorado Plateau extends into the state. Crops grown are melons, pecans, grapes, wheat, tomatoes, and other vegetables.

Exc. populations (dark blue) exist in the agricultural valleys; Fair populations (light blue) in drier, higher elevations

Exc. populations (dark blue) exist in the agricultural valleys; Fair populations (light blue) in drier, higher elevations; Rare in the mountains

The farmlands of New Mexico are excellent areas for the installation of nest boxes for the purpose of using barn owls as contributors to integrated pest management programs. Prey includes troublesome voles and pocket gophers, as well as shrews and deer mice.

Perhaps the best concentrations exist on the High Plains that cover the eastern third of the state. Researchers have discovered a heavy dependency of barn owls on nesting in abandoned buildings, evidence that manmade structures may be bolstering populations, and also suggesting that as these buildings disappear, the barn owl may decline. However barn owls also nest under railroad bridges, in culverts, cisterns, and often dig their own burrows in the soft banks of arroyos.

 

Barn Owls of New York

As shown by the range map, barn owls are more common in the southern half of the state, and most common near the southern coast. The barn owl’s best populations occur at Kennedy Airport, Staten Island, and the north shore of Long Island around Oyster Bay. Other known breeding has occurred in the Finger Lakes region, Hudson Valley, Genesee Valley, Wayne and Monroe counties along Lake Ontario, and the lowlands of Lake Erie.

Good populations clustered in the very south, scattered elsewhere

Good populations clustered in the very south, scattered elsewhere. Map based on Natural Heritage analysis of habitat and known locations.

A comparison of the latest two New York Breeding Bird Atlases show the number of blocks in which probable or confirmed breeding was recorded declined from 64 in 1988 to 28 in 2005 (out of a total of 126 Breeding Bird Atlas blocks). One thing to keep in mind however is the high number of heavy snowfalls that occurred between the first and second set of surveys which may have affected the outcome in 2005.

However, farmland is decreasing statewide, partly from reforestation and partly from development, and the type of farming has moved from hay and cattle to row crops such as soy (which is not good barn owl habitat).

The installation of nest boxes in New York farmland has met with good success and more nest box programs appear to be a good conservation approach.

A trip through southern and south-central NY in 2016 revealed a decrease in apple orchards, hay, and small farms. Over hundreds of miles of driving, not a single barn owl was seen dead on the roads, which would indicate that barn owls are very scarce in those regions. Nonetheless, plenty of good habitat remains, and so indeed do large trees and old barns. It may be that the barn owl populations in mid-state could rebound through being populated by young owls dispersing from the coastal regions as long as nesting sites were made available.

Barn Owls in New Hampshire

With 81% of its land covered in forest and severe winters, the barn owl is essentially non existent in NH

With 81% of its land covered in forest and severe winters, the barn owl is essentially non existent in New Hampshire

As the second most forested state in the nation, with forest covering 81% of the land area, and with routinely severe winters, the barn owl is essentially non-existent in New Hampshire. As testimony to its tenacity in expanding its territory, and despite these very adverse conditions, an actual breeding record exists from the town of Hollis in 1977, and they may occasionally be seen in southeastern New Hampshire where the climate is a bit milder.

Other species of owls do well in the state however, with four that breed regularly here, including the great horned owl, barred owl, screech owl, and saw-whet owl.

 

Barn Owls in Nevada

Barn owl populations are excellent in Nevada

Barn owl populations are excellent in Nevada

The most arid state in the union, Nevada is comprised of four basic eco-regions. The Northern Basin and Range is generally dry, but range land is widespread and irrigated agriculture occurs in eastern basins between the mountains. The Sierra Nevada in the western part of the state is a high mountain range covered in conifers. The Central Basin and Range contains a great deal of grazing land for cattle. The Mojave Basin and Range is the hottest and driest of the four.

Barn owls range throughout the state at elevations below 5000 feet. They are most common in agricultural areas. In the northwestern valleys, where much hay is grown, barn owls live in high concentrations. Here they nest in the huge stacks of hay bales that farmers assemble for curing before shipping. One problem that wildlife officials face is that often the farmers need to move the hay to market before the barn owls have finished fledging. Teams of wildlife rehabbers do a great deal of work every breeding season in raising and releasing young barn owls that were evicted from their haystacks. In the south central region, good populations of barn owls nest in abandoned hard rock mines. Over ten thousand such abandoned mines exist in the state, and barn owls utilize them frequently, usually nesting within fifty feet of the surface. In the northeastern region, barn owls often carve out nesting hollows in riverbanks.

One other area where barn owls concentrate is in the very southern tip of the state where, oddly, vineyards and fruit orchards have been established in the Mojave Desert.

The main prey animals in Nevada are the long-tailed vole, the mountain vole, the kangaroo mouse, and the kangaroo rat.

Barn Owls in Montana

iStock_000020901530MediumBiologist Denver Holt of the Owl Research Institute in Charlo, Montana reports that the first record of nesting in the state was in 1992, a surprisingly recent occurrence. Recently a number of nests have been discovered in the Mission Valley at an elevation of 3000 feet, where fertile soils, pasture, cattle, crops, and a national wildlife refuge contribute to good habitat. Here they nest in natural holes and juniper root systems in the clay cliffs.

The bird is most populous in the Mission Valley that lies within the Mission Mountains, with good possibilities in the Bitter Root Valley, and

Montana barn owls are most common in the western reaches and scattered through the rest of the state

Montana barn owls are most common in the western reaches and scattered through the rest of the state

then scattered in the rest of the state. It may be that other good populations in other parts of the state remain to be discovered, especially in agricultural areas at lower elevations. Although some authorities have cautiously called the barn owl a “rare visitor” to the state, it is clear that the barn owl breeds in the state, with successful breeding pairs in years without heavy snowfalls, and populations nearly wiped out during the worst winters, only to recolonize in subsequent seasons.

The large amounts of pasture, hay, and grasslands provide very adequate hunting, but the northern latitude tends to regulate numbers by severe winters. Undoubtedly the occurrences are scattered, and low in number in most areas. Yet the bird has been recorded year round.

Barn owls are most common in the western valleys and scattered throughout most of the state

Barn owls are most common in the western river and agricultural valleys (Green) and scattered throughout most of the rest of the state (Yellow)

Barn Owls of Mississippi

iStock_000020901530MediumWith a large cattle and hay industry, extensive rice production, numerous poultry farms, and southeastern saltwater marshes, Mississippi possesses excellent barn owl habitat in many areas of the state.

Although the Mississippi State Department of Wildlife has conducted no in-depth studies, and Turcotte and Watts in The Birds of Mississippi (1999) list it as a rare to uncommon resident, interviews of wildlife rehabilitators in north, central, and southern Mississippi reveal the barn owl to be highly common. It ranked as either the most common, or second most common owl brought in (the barred owl and great horned owl being the others).

Ranging throughout the state, most common in NW rice fields, central pastures, and SE marshes

Ranging throughout the state, most common in NW rice fields, central pastures, and SE marshes. Dark blue = excellent; Light blue= Good; Green = fair; F = forest/mixed forest & fields

The barn owl’s most common nesting site in the state is reported by rehabbers to be along the edges of woods, either in deer blinds, or trees (especially native locusts which split to create sizable cavities).

With the entire southern third and the eastern half of the state mostly covered in forests, barn owls are concentrated in areas of agriculture in these portions of the state. The north central counties, with less forest, and more hay and cattle, as well as the eleven-county rice-growing area in the northwest, likely support good populations of barn owls.

Barn Owl Potential in Mississippi Rice Fields

Rice is farmed intensively with few trees left standing and few places for barn owls to nest. But with dense populations of marsh rice rats consuming significant amounts of the harvest, rice farms in the state could well benefit from barn owl nest box programs. Barn owls would easily detect and inhabit nest boxes in these fields that contain so many rodents.

Rice fields can attract high barn owl numbers

Rice fields can attract high barn owl numbers

Barn Owls in Minnesota

Young barn owls chicks

Young barn owls chicks

Rare in the cold and snowy climes of Minnesota, the barn owl is occasionally seen in farmland, mainly in the southern part of the state. However, they have also been seen near Duluth and other northern Minnesota sites. According to the raptor center of the University of Minnesota, there have been less than ten recorded nests in the state.

Barn Owls in Michigan

Barn owls ready to fledge

Barn owls ready to fledge

Listed as endangered in Michigan, the last breeding pair was recorded in 1983. A single barn owl was sighted in 2000, so when a barn owl was found on the floor of a barn in Coopersville in 2012, it was a notable event. Barn owls, which are very secretive, may be a bit more common than suspected, but not much more due to the state’s severe winters and frequent, deep snowfalls. These lightly-feathered, long-legged owls are highly susceptible to periods of deep snow.

Barn Owls in Massachusetts

IMG_8134More populous in the southern end of the state, the highest populations occur on Martha’s Vineyard, Nantucket, and off shore islands, all of which have milder winters than the mainland. Occasional sightings have also been recorded in the Housatonic River Valley in the west and the Connecticut River Valley that runs through the center of the state. With its severe winters, Massachusetts harbors populations that ebb and flow according to the mildness of the seasons, however barn owls have been recorded in Massachusetts since the 1800’s and were first recorded nesting on Martha’s Vineyard in 1928.

The owl is listed as a species of Special Concern in Massachusetts.

Good places for sighting a barn owl in Massachusetts are Felix Neck Wildlife Sanctuary in Edgartown and Long Point Wildlife Refuge, both on Martha’s Vineyard.

Massachusetts Barn Owl Occurences

Massachusetts Barn Owl Occurences