OWLSOur Feathered Mousetraps

Great Horned OwlFeather tuftsYellow eyesTiger of the Treetops

Aggressive20 inches tall5 foot wingspanConifer woods

Defensive postureStay away!

Great Horned owlets

On the menu:

On the menu:

On the menu:

On the menu:

On the menu:

Barred OwlQuiet natureBrown eyesTeddy Bear of the air

Bars or stripesCamouflage18 inches tallWoods near rivers, ponds, or lakes

Cavity Nesters

Barred owlet

On the menu:FrogsFishCrayfishSmall mammalsSongbirds

Swallow food whole

Head first

Gulp!

Whats next?

Owl PelletsRegurgitated 8 to 16 hours laterContains fur, feathers, and bones

The leg bones connected to the

Where in the world?

Look at base of trees where owls have been roosting

Eastern Screech OwlAggressive8 inches tallWild cat of the air

Two colorsGray-brown or redFound in small woodlots & orchards

On the menu:Large insectsMiceSmall songbirdsReptilesAmphibians

Iowas Three Common Owls

Iowas Endangered SpeciesBarn OwlOnce commonMonkey-like faceDNR reintroduction attempted

Barn Owl chicks

Owl Visitors to IowaBurrowing Owls

Common in western Plains statesVisits NW IowaNests underground

Owl Visitors to IowaLong-eared Owl

Long feather tuftsSmaller than Great Horned OwlFound in Minnesota and Canada

Owl Visitors to IowaShort-eared Owl

Short feather tuftsOften seen in daylight Found near fields, prairies, and marshes

Owl Visitors to IowaSaw-whet Owl

Smaller than ScreechFound in coniferous North woods

Owl Visitors to IowaSnowy Owl

Found in ArcticVentures south for food in winterLarger than Great Horned Owl

Owl Visitors to IowaWhat is it?

Large white birdFeather tufts presentRare arctic phase of Great Horned Owl spotted in Marshall County

AdaptationsExcellent eyesightLarge eyes set in facial diskCan see 10 times better at night Sometimes 100 times better!

AdaptationsExcellent hearingTwo slits on each side of headHandy feature on moonless nights

AdaptationsHawks have scale-covered legsOwls have feather-covered legsFeathers help to muffle sound

AdaptationsSnowy Owl feet have an abundance of feathersGreat leg warmers for cold arctic nights!

AdaptationsClose-up of outer primary flight feathersComb-like serrationsCreates silent flight

Predator: Friend or Foe?Historically, predators were persecutedToday, owls and hawks are protectedPredators have an important role controlling prey populations

*We will look at Iowas three common owls, a selection of visiting owls and owl adaptations which make them excellent feathered mousetraps.*This Great Horned Owl with its piercing yellow eyes and sharp talons is known as the Tiger of the Tree Tops.*This aggressive owl stands about 20 tall and has a 5 wingspan. Listen for its hooting in deep woods, especially woods containing evergreen trees.*When provoked owls may take on this defensive posture. By fluffing up its feathers and holding its wings out, the owl makes itself appear larger in order to scare off intruders.*Perhaps this owl was trying to protect her chicks after they had fallen out of the nest. Great Horned Owl chicks grow quickly and eat a large amount of food.*We often call owls mousetraps because their diet is high in mice, but other menu items are rabbits*Thirteen-lined ground squirrels..*Snakes.*Songbirds*And an occasional skunk making for a smelly Great Horned Owl! The owls poor sense of smell comes in handy here.*The Barred Owl with its dark brown eyes and quiet nature is known as the Teddy Bear of the Air.*The Barred Owl, which is slightly smaller than the Great Horned Owl, stands about 18 tall. It gets its name from the horizontal and vertical bars on the front of the bird.*Like other owls, the Barred Owl is a cavity nester. That is, they nest in holes of standing dead trees.*Sometimes in a windstorm the tree may break at this weakened point, thus exposing a curious chick or two.*Since the Barred owl is found in woodlands near water, they feed on frogs, fish, crayfish, small mammals and birds.*Owls swallow their food whole without plucking feathers, fur or bones.*The prey is swallowed head first*With successive gulps the prey in this case a 13-lined ground squirrel is slowly swallowed.*The owl seems to be saying You didnt think I could eat the whole thing, did you?*After 8 to 16 hours, the digestible material is consumed and the owl regurgitates the fur, feathers and bone in a pellet form. This action removes bacteria from the throat of the bird which, if left in place could grow and choke the bird.*This owl pellet can be taken apart to determine the owls diet.*Scientists often go to the woods to collect owl pellets for study. *The best place to look for owl pellets is at the base of trees where owls have been roosting. Pellets show up well against the snow.*Dont let the small size of this owl fool you! Know as the Wild cat of the Air this Screech Owl is very aggressive.*These owls come in two colors grayish brown or red. The coloration has nothing to do with age, sex of the bird, or season, its just a genetic trait like our hair or eye color. Look for this species of owl in neighborhoods with large trees, small woodlots or orchards.*Prey includes large insects like grasshoppers, mice, small songbirds, reptiles and amphibians.*The three owls weve just discussed are commonly found in Iowa. Do you remember their names?*The Barn Owl is an endangered species in Iowa. Many years ago the Iowa DNR tried a reintroduction program but it was unsuccessful. The Barn owls reproduced but the Great Horned Owl thought baby Barn Owls were tasty and out competed the Barn Owl. Report any sitings of Barn Owls to the DNR or County Conservation Board.*Lets take a look at some of the owls which might visit Iowa. First well look at the Burrowing Owl. Normally found in the western Plains states it can sometimes be seen in NW Iowa. This species nests underground in prairie dog towns.*The Long-eared Owl is so-called because of its long feather tufts. These tufts are not ears at all, but simply feathers. This winter visitor is normally found in Minnesota and Canada.*Can you see the short feather tufts on this owl? The Short-eared owl prefers the ground although it doesnt enter holes like the Burrowing Owl. This winter visitor can often be seen in daylight near fields, prairies and marshes.*Another winter visitor is the Saw-whet Owl. Although slightly smaller than the Screech Owl it is quite capable of catching a mouse or two for dinner. It is a very calm owl which is normally found in coniferous woods to the north.*The Snowy Owl ventures down from the Arctic in search of food. They have been spotted in Marshall County during many winters. Adult males are pure white. Adult females and young males have black spots. *At first glance, this appears to be another Snowy Owl, but look closely at its head. Can you see feather tufts? This is the rare arctic phase of the Great Horned Owl which was seen in Marshall County one winter.*Owls have several adaptations that make them effective mousetraps. One is there excellent eyesight. Large eyes are set in the center of a circular facial disk. This acts as a funnel allowing owls to see 10x better than we can at night. In some species its 100x better! You could compare that to humans using a flashlight or street light to navigate in while owls could use the starlight alone.*What if its cloudy and theres no starlight or moonlight to with which to navigate? It just so happens that owls also have excellent hearing. They dont have external ear flaps like we do, but rather just slits in the side of their head. See the white patch between the two pencils in this photo? Youre looking right through the owls ear into the white stuffing on the inside of this taxidermy mount of the owl.*In comparing the legs of hawks and owls, youll note the hawks have only a scaly covering while owls have feathers covering their feet. This feathery covering helps muffle sound which might give away an owls presence.*In the case of the Snowy Owls feet the abundance of feathers helps protect its feet from the cold Arctic air as well.*A close-up look at the outer primary flight feathers show another interesting adaptation to quiet flight. The comb-like serrations break up the air flow over the wing to prevent whistling as the owl flies. A great way to sneak up on prey, dont you think?*Because owls are predators, they have often been persecuted. They have been shot and hung on fences as an example. Fortunately, owls and hawks are protected. Like other predators, they have an important role to play in controlling prey populations such as rodents.*Now that you have a greater awareness of owls, I hope youll realize that owls are an important natural resource which need our continued support.