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Barn Owls in Kentucky

HAVE YOU SEEN ME?
The Barn Owl is a
rare species in Kentucky. The Kentucky Department of Fish and Wildlife
Resources would like to learn more about our nesting Barn Owls, but we need your
help. Please report Barn Owl nests to 1-800-858-1549 or kathryn.heyden@ky.gov.
For information on
identifying Barn Owls, please visit:
http://fw.ky.gov/owlidentification.asp
For more information
on Barn Owls in Kentucky, please scroll down.
Barn Owls in Kentucky
Barn Owl Status-
Past and Present
The Barn Owl (Tyto alba) is a nocturnal
raptor found in open habitats where it preys primarily on rodents and other
small mammals. Although the species is one of the most widely distributed birds
in the world (found on all continents except for Antarctica), in Kentucky,
records of nesting Barn Owls have been quite rare both historically and in
modern times. Due to the predominance of forested habitat, the species was
probably very rare or absent from much of the state prior to European
settlement. During the late 1800s and early 1900s, the species likely colonized
open habitats created by settlers (Palmer-Ball 1996).
The infrequency of reports of this species in
Kentucky is somewhat surprising because much suitable habitat in the form of
pastures, hayfields, croplands, reclaimed surface-mine lands, and restored
grasslands is present. In fact, 38% of the state is composed of undeveloped,
open land (grassland/herbaceous, pasture, cropland, etc.). With such an
abundance of suitable habitat, it seems Kentucky should host an abundance of
Barn Owls. It is likely that the scarcity of breeding records is in part due to
the elusive nature of these nocturnal predators. Mengel (1965) noted that the
paucity of published records likely exaggerated the perceived rarity of the
species, and he stated that during his time most rural people were familiar with
the species, implying that Barn Owls must have occurred “widely and regularly.”
This has not been the case in recent years; despite efforts to track breeding
records for this species, detailed reports have remained few in number. For
example, only seven confirmed breeding records were documented 1985–1991 during
the state’s breeding bird atlas project (Palmer-Ball 1996).
Barn Owls have gained conservation concern
throughout most of North America in recent years due to noticeable population
changes. Severe declines have been recorded in several Midwestern states (Colvin
1985, WDNR 2005). Many possible causes for these declines have been identified
and examined including habitat loss, human-related mortality, variability in
prey populations, low survival during severe winters, predation, pesticides, and
limited number of suitable nest sites (Altwegg et al. 2006, Colvin 1985, Stewart
1980). Without doubt, a combination of these factors has affected Kentucky’s
Barn Owl population.
Due to local conservation concern, the Barn Owl has
been considered a Species of Special Concern by the Kentucky State Nature
Preserves Commission since 1986 (Warren et al. 1986), and as a Species of
Greatest Conservation Need in Kentucky’s State Wildlife Action Plan (KDFWR
2005).
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Barn Owl Monitoring
Conservation
actions for declining species are usually best implemented when the
status of the population is known. In the case of Barn Owl, so little
was known about its status in Kentucky that the first step was to
conduct a statewide inventory, beginning in 2010.
During the 2010 inventory, twenty-six
confirmed Barn Owl nest locations were documented. Additionally, 7
locations were recorded for roosting, non-breeding Barn Owls. Most
nests were found on privately owned land, although three were in nest
boxes on WMAs. Nests were found in a variety of structures including
nest boxes, silos, grain bins, barns, hollow trees, chimneys, and even
shooting houses. Nests were scattered throughout much of central and
western Kentucky, but none were reported in far eastern Kentucky (Figure
1). Although active nests were documented in 23 counties, most counties
produced only a single nesting record. Once located, the productivity of
each Barn Owl nest was monitored where possible.
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Figure 1. County
distribution of known nesting Barn Owl pairs documented during 2010. |
Barn Owl Nesting
Barn Owls do not bring any
vegetation to the nest. They simply lay eggs on the floor of the nesting
structure or on pellets. Nesting is typically initiated during spring
(March–May) and eggs are incubated for about 32 days. Young fledge at about 60
days of age, usually by the end of
July. Brood sizes usually vary between 3 and 8 young, though larger broods have
been documented elsewhere.

A Barn Owl nest in grain bin
containing six young owls.
Photo by: Kate Heyden
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During the
2010 monitoring, biologists were surprised to find that nesting activity
continued into late summer and fall/winter with five nests documented
with young after September! Surprisingly, “double-brooding” or
attempting to raise two nests of young in one year was documented at two
of these late nests which continued into December. Nesting during
fall/winter and double-brooding has been reported occasionally in
bordering states including Illinois and Ohio (Walk et al 1999, Shipley
and Scott 1999), but had not been previously reported in Kentucky.
Barn Owls
which nest in Kentucky appear to be non-migratory and usually remain on
site year-round, although different locations may be chosen for roosting
seasonally.
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A Barn Owl peers out
of the entrance to a nest box in a Wildlife Management area barn.
Photo by:
Kate Heyden |
| Barn Owl Diet
Barn Owls, like
other owls regurgitate undigested parts of food in pellets. Since Barn
Owls often swallow prey whole, pellets usually contain fur, skulls and
bones. Pellets are often left at the nest site or roost site, making it
easy to determine what the owls have been eating. KDFWR staff have
opportunistically dissected pellets found at nesting and roosting
locations to identify prey remains. Identifiable skulls are often those
of voles (Microtus spp.) or Southern bog lemmings (Synaptomys
cooperi), although mice (Peromyscus spp. and Mus musculus)
skulls have also been found. Other, less common prey items that have
been noted include crawfish and bird remains. The observed dominance of
voles in the diet of Barn Owls was consistent with other studies on the
contents of Barn Owl pellets in Kentucky (Brown 1989, Thogmartin et al
1999) and elsewhere in inland North America (Marti 2009). |

Barn Owl pellets are usually 1-1 ½ inches
thick and 1-3 inches long.
Photo by: Kate Heyden |
Management Efforts
Suitable nest site
availability in the proximity of areas with a large prey base is assumed to be a
major limiting factor for Barn Owl populations. Providing
nest boxes near source populations has been found to successfully increase
nesting populations (Marti et al 1979). The inclusion of the Barn Owl as a
species of greatest conservation need in Kentucky’s State Wildlife Action Plan
(KDFWR 2005) resulted in establishment of a program to install nest boxes in
suitable habitat on WMAs and other public lands in 2006. Initially, efforts
focused on installing nest boxes in barns and sheds near large tracts of
grassland habitat. Nineteen nest boxes have been installed in barns or sheds on
public land since 2006. However, several WMAs that have good Barn Owl habitat,
do not have barns that are conducive to nest box installation. Thus, in 2008, a
new nest box was designed that could be mounted onto a tree or pole. Since 2008,
18 nest boxes have been installed on trees and poles on public lands.
Although several nest
boxes on public lands have already become active, in 2010 the nest box focus
switched to maximizing the productivity of existing Barn Owl nests - whether
they are on public or private land. Nest success may be hindered at unreliable
nest sites, perhaps contributing to Barn Owl declines. For example, many nests
are discovered when hollow trees are cut down, grain bins are drained, or old
barns are demolished. In 2010, KDFWR worked to ensure that all known nesting
Barn Owl pairs had a safe and permanent nest site by installing 29 additional
nest boxes at locations with known pairs. Sometimes Barn Owls choose nest
locations that present an inconvenience for the landowner or will not be
available in future years (e.g. a hole in an attic vent that is planned to be
fixed). KDFWR works with landowners to encourage Barn Owls to nest in a location
which is convenient for the landowner and safe for the owls. The department also
ensures that destroyed Barn Owl nest sites (removed nest trees) are replaced
with a nearby nest box in an undisturbed area. It is
hoped that these efforts will encourage a more stable Barn Owl nesting
population statewide.
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Banding Efforts
In hopes of learning more about the
dispersal, movements, and survival of Kentucky Barn Owls, KDFWR
personnel bands Barn Owls, when possible.
Owls are banded by qualified KDFWR personnel with federal
permits. Each owl wears a lock-on aluminum leg band with a unique
9-digit number. Information on age and sex are recorded using a
combination of measurements and plumage characteristics. KDFWR
bands nestling Barn Owls at some nest locations and also cooperates with
local wildlife rehabilitators to the band and release rehabilitated Barn
Owls. These owls have been brought to
licensed wildlife rehabilitators and treated for various reasons
including poisoning, vehicle collisions, nest destruction, and falling
from a nest. When recovered, these owls are banded and released in or
near to a vacant nest box that has been installed in suitable habitat. |

A young Barn Owl at
the time of banding.
Photo by:
Kate Heyden |
The Future
Barn Owl nest monitoring, nest box installations and
banding will continue as time and funding permits, until the nesting population
demonstrates growth and sustained stability.
What can you do to help?
Because most Barn Owls are on private land, the
extent of KDFWR’s knowledge of and ability to help Kentucky’s population depends
greatly on the public’s cooperation in reporting sightings. Please report Barn
Owl nests/roosts by calling 1-800- 858-1549 or e-mailing kathryn.heyden@ky.gov.
Landowner and exact nest location information are kept confidential, and locations are released
to the public only at the county level. KDFWR works with landowners to encourage
Barn Owls to nest in locations that are convenient for the landowner and safe
for the owls.
Due to limited time and funding, KDFWR is not generally
able to install Barn Owl nest boxes on private land unless there is a local pair
in need of a safer nest site. However, many landowners have expressed interest
in installing a nest box in hopes to attract a pair of Barn Owls to their
property. Barn Owls are often welcomed by farmers and landowners since they
help to control rodent populations. Interested
landowners that would like to install their own nest box can find construction
plans via the KDFWR website at:
http://fw.ky.gov/pdf/barnowlboxes2010.pdf.
Private landowners are encouraged to inform KDFWR of any nest boxes installed
and if they become active. Leaving hollow trees if they do not endanger your
house or buildings is also recommended to provide Barn Owls and other species
with nest sites.
Acknowledgments
A project of this scope would not be possible without the
support of many volunteers, cooperators, wildlife rehabilitators and private
landowners. We would especially like to express gratitude to the many private
landowners which have become a host for this rare species. Due to this species’
scarcity, the contribution made by providing a single safe nesting site for each
pair of Barn Owls is significant.
Literature Cited
Altwegg,
R., A. Roulin, M. Kestenholz, and L. Jenni. 2006. Demographic effects of extreme
winter weather in the Barn Owl. Oecologia 149: 44-51.
Brown, R.K. 1989. Food habits
of Kentucky owls. The Kentucky Warbler 65:38-48.
Colvin, B. 1985. Common Barn
Owl population decline in Ohio and the relationship to agricultural trends.
Journal of Field Ornithology 56: 224-235.
KDFWR. 2005. Kentucky's
Comprehensive Wildlife Conservation Strategy. 2005. Kentucky Department of
Fish and Wildlife Resources, #1 Sportsman's Lane, Frankfort, Kentucky 40601.
http://fw.ky.gov/kfwis/stwg/.
Marti, C.D., P.W. Wagner, and
K.W. Denne. 1979. Nest boxes for the management of Barn Owls. Wildlife
Society Bulletin 7:145-148.
Marti, C.D. 2009. A
comparison of methods for estimating prey biomass of Barn Owls. Journal of
Raptor Research 43:61-63.
Mengel, R.M. 1965. The
birds of Kentucky. American Ornithologists’ Union Monograph No. 3. The Allen
Press, Lawrence, KS.
Palmer-Ball, B., Jr. 1996.
The Kentucky breeding bird atlas. University Press of Kentucky, Lexington,
KY.
Shipley, K.L. and D.P. Scott.
1999. Barn Owl Distribution and Productivity, 1998. Ohio Department of
Natural Resources, Division of Wildlife. Olentangy Wildlife Research Station,
Ashley, OH 43003. Unpublished Technical Report. 5 pp.
Thogmartin, W.E., A.T.
Morzillo, H.A. Brown, and J.H. Herner-Thogmartin. 1999. Feeding habits of
Barn Owls at Yellowbank Wildlife Management Area, Breckinridge County, Kentucky.
Cooperative Wildlife Research Laboratory, Southern Illinois University,
Carbondale, IL 62901. Unpublished Technical Report. 19 pp.
Walk, J.W., T.L.
Esker, and S.A. Simpson. 1999. Continuous nesting of Barn Owls in Illinois.
The Wilson Bulletin 111:572-573.
Warren, J.L.,
Jr., W.H. Davis, R.R. Hannan, M. Evans, D.L. Batch, B.D. Anderson, B.
Palmer-Ball, Jr., J.R. MacGregor, R.R. Cicerello, R. Athey, B.A. Branson, G.J.
Fallo, B.M. Burr, M.E. Medley, and J.M. Baskin. 1986. Endangered, threatened,
and rare plants and animals of Kentucky. Transactions of the Kentucky Academy
of Science 47:83-98.Wisconsin Department of Natural Resources (WDNR). 2005.
Wisconsin’s Strategy for Wildlife Species of Greatest Conservation Need.
Madison, WI.
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