Thursday, April 3, 2008

Barn Owl--Tyto alba

Barn Owl aka The Ghost Owl

My friend Gloria and I once walked under a Barn Owl Nest while bird watching at Turtle Rock Nature Center years ago. As we looked up, three downy owlets looked down at us. For quite a while we all gazed at each other. They were very cute and curious. For a birder, seeing an owl is always a wonderful treat. Especially during the daytime. With incredible eyesight and hearing, owls are very efficient nocturnal hunters. Out there in the dark night, they seem mysterious and fascinating.



Barn Owl profile. Such a beautiful bird. This is a female Barn Owl from a South Bay Wildlife Rehab show at Wildbirds Unlimited, Huntington Beach in October of 2008. Her name is Miss Luna.

Inhabiting all continents except Antarctica, Barn Owls are one of the most widespread owls in the World. They even inhabit large islands including Hawaii--although they were introduced there as rodent control. They are residents of Orange County. They are cavity nesters and adapt easily to buildings. Unconcerned about humans nearby, they have spread throughout the world nesting in barns and buildings. There have been reports of Barn Owls landing on ships offshore. They evidently will fly over the ocean to ships and islands.



Check out those long gams! Miss Luna has a moment with her handler with whom she lives.

Barn Owls have a heart-shaped white face rimmed with a brown ridge of feathers. Their unusual face has earned them the nicknames "Ghost Owl" and "Monkey-faced Owl." Its beautiful color is the reason for another nickname-- "The Golden Owl." They are brownish and white. Small brownish spots sprinkled all over the front and heavy metallic silver sprinkles on the back of the head, back, and wings. They do not hoot. They make hissing and screeching noise. It can be quite unnerving. Barn Owls have very long legs. Like other owls, they must turn their heads to look around. Their large eyes cannot move like ours do. The largest Barn Owl race is in the United States. Like many raptors, females are larger than the males.

Notice the brown and silver speckles. Not many birds have this silver color.


Owls are nocturnal. Barn Owls are one of the most nocturnal owls we have. They hunt at night using their excellent hearing and sight. They hunt low over the ground seeking out small mammals--mainly rodents. They also eat reptiles, small birds, and sometimes fish and insects. One study found crayfish in Barn Owl pellets. Like other owls, they regurgitate the inedible parts like the bones, fur, feathers, etc. in a pellet that falls to the ground under their perch. Lots of pellets will tell a birder that an owl's favorite perch is overhead. Usually, it is only during nesting season will you see a Barn Owl out in twilight, but in some areas the Barn Owl is seen more frequently during the day or crepuscular times of day. Its specialized feathers--similar to other owls--give it an almost silent flight.



Nap Time at the Orange County Zoo. A pair of Barn Owls sleeps the day away like good nocturnal animals. Birders can get a good idea of what Barn Owls are like by visiting the OC Zoo in Irvine Regional Park in the City of Orange .


During three months, a family of Barn Owls can eat 1,000 rodents. A single Barn Owl can eat 2,000 rodents a year. Most of these are rats, mice, and gophers. Rabbits are too large for Barn Owls to take. Barn Owls fly close to the ground looking for prey. This can cause fatalities when the owls flying low in search of prey cross a street. Because Barn Owls kill and eat many rodents every year--especially while they are raising young--farmers, land owners, and members of city and county government are beginning to install Barn Owl nesting boxes on their property in trees, on poles, and in barns. Encouraging Barn Owls on one's property can greatly reduce rodent problems with little cost or effort by merely installing Barn Owl nestboxes. It eliminates pesticides and is a nice natural way to keep down the rodent population. Sources for Barn Owl nest boxes or plans are listed in the links at the end of this post.



Silver back of a Barn Owl. Miss Luna.

Nesting season is from February through June with the most nesting occurring from March through May. Barn Owls may start house hunting as early as December or January, and so it is good to have your nestbox up and ready by then. Barn Owls mate for life. Life unfortunately for Barn Owls is short. Just about 2 years in the wild, but 18 or more years in captivity. Barn Owls are prolific and may nest two or more times a year.






Barn Owl Miss Luna with handler at South Bay Wildlife Rehab show at Wildbirds Unlimited, Huntington Beach in October of 2008.

Some populations in warm climates may mate year-round. The male brings the food to the female, and she prepares it and feeds it to the owlets. There are an average of 4-7 eggs laid in a nest. Owlets are covered with white down. The female makes the nest at the bottom of a cavity or nestbox by shredding regurgitated pellets and placing them on the floor of the nesting area. There are records of Barn Owls nesting in burrows in the absence of trees with cavities.



Notice the Heart-Shaped face and the well-defined facial disc.

The Great Horned Owl is a formidable predator of the Barn Owl. The Barn Owl is smaller than the Great Horned Owl. It is one of the biggest challenges when rehabilitators release birds into the wild. Rehabilitators have had some success with adding Barn Owlets to a nest and having a wild Barn Owl foster the owlets. There are some successful releases of Barn Owls. The dangers for rehabilitated Barn Owls is great and not all survive.



Stretching her wings. Miss Luna.

Barn Owls are considered by some to be spooky, but if you really look at them, they are incredibly beautiful and amazing creatures. From the carefully constructed white, facial disc with its beautiful brown border to the silver sprinkling over its feathers, it is hard to find a more beautiful owl. Wildlife rehabilitators and biologists testify to the sweet personality of this predator.






Barn Owl at the Orange County Zoo at Irvine Regional Park in the City of Orange.

Birders should consider going on either owl banding trips or night "Owl Prowls" Check out Sea and Sage's field trips or Starr Ranch Audubon for opportunities. Also check out listings of field trips and activities in Orange County Wild. You may get lucky. Maybe you will actually see a Barn Owl! Have fun birding in Orange County--even at night!






OC Birder Girl Links





Great Horned Owl--Bubo virginianus








Red-Shouldered Hawk








Red-Tailed Hawk--Buteo jamaicensis







Courtesy US Fish and Wildlife-- Barn Owl --Photographer CF Zeillemaker
External Links and Resources





All About Birds: Barn Owl

Detailed article about one of the most widely distributed birds in the world.





Animal Diversity Web: Barn Owls

Very thorough article on Barn Owls.





Backyard Barnyard Owls

About the benefits of Barn Owls.




Barn Owl Headquarters

Site encouraging and advocating the green method of rodent control: Barn Owls.








Barn owls all too happy to be your rat catchers--Birds a natural and chemical-free way to control pests

From the San Francisco Chronicle, an article about the use of Barn Owls in Rodent control.








Barn Owl Project

"A special program of the Lycoming Audubon Society in cooperation with the Pennsylvania Game Commission." Good advice about nestboxes and Barn Owls.










The Barn Owl Trust

From the UK, a great site on Barn Owls.












Burrow Digging by Barn Owls


(Journal of Field Ornithology: Vol. 44, No. 1, Winter, 1973)








Cape Romain: Barn Owl nest box project


Free plans and pictures of how to build a simple nest box for Barn Owls.



Common Barn-Owls From Captive Propagation Found Nesting in the Wild


(Journal of Raptor Research: Vol. 21, No. 2, 1987)




COMMON BARN-OWL POPULATION DECLINE IN OHIO AND THE RELATIONSHIP TO AGRICULTURAL TRENDS


(Journal of Field Ornithology: Vol. 56, No. 3, Summer, 1985)







COMPOSITION AND SEASONAL VARIATION OF THE BARN OWL "TYTO ALBA" DIET IN ARIZONA



(Journal of Raptor Research: Vol. 16, No. 2, 1982)









Continuous Nesting of Barn Owls in Illinois



(Wilson Bulletin: Vol. 111, No. 4, October-December, 1999)







Desert USA: The Common Barn Owl

Good article on the Barn Owl.












eHow: How to Build a Barn Owl Nesting Box


Step by step how to build a Barn Owl nesting box.










Farmers, Conservationists Seek Return of Barn Owls


The value of Barn Owls in pest reduction and reduced costs.










Food-niche Relationships Between Great Horned Owls and Common Barn-Owls in Eastern Washington



(Auk: Vol. 101, No. 1, January-March, 1984)









Growers find barn owls protect their crops


CCN article on how Barn Owls protect crops and save money.










Habitat for Hooters



Napa County Program.










The Hungry Owl Project

Good information from the Hungry Owl Project based in San Anselmo, CA.




The Internet Bird Collection: Common Barn Owl

High quality videos of Barn Owls.



National Geographic Barn Owl Coloring Page

For kids. Color a Barn Owl.





The Oregon Zoo: The Barn Owl

Detailed Article about Barn Owls from our neighbors up north.











Over-water Flights of Barn Owls



(Journal of Field Ornithology: Vol. 50, No. 1, Winter, 1979)







The Owl Cam: Frieda and Diego

Barn Owls Frieda and Diego's home is an online Barn Owl nestbox.






The Owl Pages: The Barn Owl

Article about the Barn Owl.









Owl Research Institute

Great organization located in Montana that does research on owls of all kinds. Great newsletter. Owl Id guide under construction.






Peregrine Fund: Barn Owls

Nice article.







The Progressive Farmer: Barn Owl Nesting Box Plan

Simple plan for making a Barn Owl Nesting Box. Plan only, you have to buy the wood. They charge for the plan. Interesting that the farmers are beginning to see the value in natural and cheap rodent control.











The Proof is in the Pellet

Audubon Magazine article on how Barn Owls can be used to reduce mice, rat, and other rodents and save money for homeowners, cities, farmers and more by providing free pest removal.











SUCCESSFUL RELEASES OF CAPTIVE BARN OWLS



(Journal of Raptor Research: Vol. 14, No. 2, 1980)












Summary of California studies analyzing the diet of barn owls.

Good diet info.









Wesley the Owl


Story of the relationship between a rescued baby Barn Owl and a biologist.








WildWathCams: The Barn Owl Cam Story



Owl Cam in Washington State.











USGS: Barn Owl


Good article on the Barn Owl.




















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Tuesday, April 1, 2008

Barn Swallow--Hirundo rustica

Copyright Karen McQuade, OC Birder Girl Male Barn Swallow perched on sign on private property in Huntington Beach.

I couldn't believe my luck when I stumbled upon a little group of swallows on private property in Huntington Beach. I asked if I could take some pictures and received permission. Despite the clouds and rain that day, the sun came out for several beautiful shots.


Barn Swallow on pipe. Notice the deeply forked tail. Easy to spot in flight.

The most noticeable thing about Barn Swallows is their deeply forked tail. They are dark blue and dark chestnut on their heads and back. Their chests and belly are a lighter buffy-rufous color. They have short, wide beaks perfect for catching insects as they fly low over water and fields. The female is similar to the male, but lighter in color.



Blowing in the Wind.



Barn Swallows are the most widespread swallow species in the world. They are present in Orange County in Spring and summer. I have noticed a few at other times of year. In North America, they breed throughout the United States and Canada and parts of Mexico. The only places Barn Swallows cannot be found are in Australia and Antarctica. With that many Barn Swallows all over the world, you might guess that there are several subspecies, and you would be right. There are six subspecies of Barn Swallows world-wide.



Barn Swallow singing on the No-Fishing Sign.
Barn Swallows tend to be seen flying low over water especially and sometimes over fields. They fly close to the ground or water with their short, wide bill open to catch their favorite food, insects. They catch them as they fly. Barn Swallows are very skilled fliers, swooping in and out along pathways at San Joaquin, and low over the water there and at Bolsa Chica Ecological Reserve, Mason Regional Park, Huntington Central Park, and any place with water including small lakes and ponds. You can recognize them by the metallic blue upper parts as the whiz by and the glimpse of the their trademark deeply forked tail. I have also seen them at Long Beach by the Catalina Express swooping along the surface of the water.







Barn Swallow on the nest in Huntington Beach. It is made of mud and grass.



Nests are open and made of mud, grass, animal hair, and feathers. The mud itself researchers say consists of sand, silt, and clay. You can see the little mouth fulls of mud stuck together with grass to form an open cup. (Sometimes they use old mud nests either of their own or another bird that builds a mud nest.) Like many Barn Swallow nests, the nest above is close to an overhang. They are also often build on ledges. Barn Swallows lay an average of about 5 eggs. The babies really get noisy when Mom or Dad returns with food. They stick their heads out and open their very large mouths. They don't want the parents to miss them. Barn Swallows have switched from nesting in caves to utilizing human structures including barns to build their nests in and on. Human dwellings have provided them with many nesting sites. They also build nests under docks. Parents remove fecal sacs for young nestlings, but older nestlings defecate over the side of the nest. So watch where you stand.





Cliff Swallow Nest for comparison--enclosed with a tunnel to the nest. Picture taken at the Lion Enclosure at the San Diego Wild Animal Park.








Barn Swallow Nest from You Tube.


Pairs form during Spring of each year. Repeat pairing are not unusual--especially among successful pairs. Females tend to pick males for symmetry of tails and wing, length of tail feathers, and color. Especially in North America, females like males with redder chests. Breeding season is May through August, though in Southern California, you may see them earlier. I have seen Barn Swallows nesting as early as late March.




Copyright Karen McQuade, OC Birder Girl

Barn Swallow Male. Note the long, forked tail.

In a very interesting North American study (see references below), the chest feathers of barn swallows were darkened to the color of the darkest males in the area. Suddenly these little guys became popular. The researchers where surprised to discover that the male birds they had darkened had an increase in their testosterone levels. The extra attention really had an affect on these male swallows. They were definitely more successful in breeding.






Copyright Karen McQuade, OC Birder Girl


Resting.


Like other birds, swallows sometimes have helpers. Barn Swallows are no different. They sometimes have birds who are not one of the mated pair who help defend the nest. These helpers are often male and evidently may have ulterior motives, because they may mate with the female on occasion as well. They do not help feed the offspring. The mated pair--mostly the female feed them the insects they catch in a pellet-like form. Immature Barn Swallow may assist in the feeding of nestling. (Read my post on Western Bluebird--Sialia mexicana to learn about Tree Swallows helping the Western Bluebird.) Tree Swallows are evidently pretty helpful. A nature center in Illinois put some orphaned Barn Swallows in a Tree Swallow nest and they raised them right along with their own.





Barn Swallows. Notice the short, wide beak, perfect for gathering insects as it swoops through the air.

Barn Swallows tend to nest together in colonies. Perhaps it is safety in numbers of perhaps a good nesting area is a popular one. They also like to sing together in pairs and as a group. They are a social kind of bird. You usually don't see one Barn Swallow, you see a large group.





Barn Swallow on the Ledge

Predators mostly target the nestlings. The predators are varied. From bullfrogs to owls. Hawks, Falcons, and Owls target the adult Barn Swallow as well, but their swift, skilled flight leaves many predators behind in the dust. They do form a helpful relationship with one raptor, the Osprey. They often nest near the Osprey who intimidates other predators due to sheer size. The Barn Swallows provide an early and loud warning system when there is danger afoot.













Most Barn Swallows live about 4 years with some exceptional individuals living twice as long. They will defend their nests against predators by mobbing species like Boat-tailed Grackles, Red-winged Black Birds, Snowy Egrets, Sharp-shinned Hawks, Loggerhead Shrikes, and others. These gregarious birds hang out together for protection and social interaction.

Two Barn Swallows on a light fixture.


When you are out birding in Spring and Summer, don't forget to watch low to the ground and water for the swift flying bird with the deeply forked tail. You may well see the Barn Swallow.



Copyright Karen McQuade, OC Birder Girl Front View of Male Barn Swallow




Loggerhead Shrike--Lanius ludovicianus





Osprey--Pandion haliaetus





All About Birds: Barn Swallow

Detailed article about Barn Swallows.








ANALYSIS OF MATERIALS IN CLIFF AND BARN SWALLOW NESTS: RELATIONSHIP BETWEEN MUD SELECTION AND NEST ARCHITECTURE



(Wilson Bulletin: Vol. 89, No. 4, October-December, 1977) These researchers got into the mud and figured out what was in it. Conclusions show the differences in mud may be related to the different types of nests built by Cliff and Barn Swallows.







Animal Diversity Web: Barn Swallow

Thorough article on the Barn Swallow. Lots of information.





Animal Planet's Wild Bird Guide: Barn Swallow

Short article. Awesome picture.










BioKids: Barn Swallow



Great article for kids and adults.








BirdWeb: Barn Swallows

Good information from Seattle Audubon.






Chipperwood Bird Observatory: Barn Swallow

Great information and pictures from the Chipperwood Bird Observatory in Indiana.





Colonial Breeding in the Barn Swallow (Hirundo Rustica) and Its Adaptive Significance



Snapp explores the significance of colonial breeding in Barn Swallows. (Condor: Vol. 78, No. 4, July-August, 1976)










For Barn Swallows, Feathers Make the Man, says CU-Boulder study

Artificially dyed male Barn Swallows get boost in hormones just by looking good. Watch the video about the study here.













By Rebecca J. Safran. She discusses her participation in a study of color and mate selection in North American Barn Swallows.











Helpers at the Nest in Barn Swallows



(Auk: Vol. 94, No. 3, July-September, 1977)







INTERFERENCE BY HOUSE SPARROWS IN NESTING ACTIVITIES OF BARN SWALLOWS



(Journal of Field Ornithology: Vol. 60, No. 3, Summer, 1989) Recorded instances of how those notorious House Sparrows interfere with Barn Swallow nests.











Internet Bird Collection

High quality videos.









(Wilson Bulletin: Vol. 87, No. 1, January-March, 1975)






National Wildlife Federation: Barn Swallow Migration

Good article on Barn Swallow Migration.




Nature Works: Swallows

Good article on the swallows.



















(Wilson Bulletin: Vol. 89, No. 4, October-December, 1977)


















(North American Bird Bander: Vol. 10, No. 1, January-March, 1985) I am beginning to think Tree Swallows are altruistic. They help Western Bluebirds and Barn Swallows. What a bird.












State of Washington: Living with Wildlife








USGS: Barn Swallow

Short, but good article.
































NOTE: ALL Photographs are copyright Karen McQuade aka The OC Birder Girl. Unauthorized copying is prohibited.




















































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