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owls - nocturnal raptors. most are solitary a group of owls is a parliament predators of small mammals, insects, and other birds a few species specialize in hunting fish. Classification:. Domain: Eukaryota Organisms with complex cells Kingdom: Animalia Phylum: Chordata
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owls - nocturnal raptors • most are solitary • a group of owls is a parliament • predators of small mammals, insects, and other birds • a few species specialize in hunting fish
Classification: Domain:Eukaryota Organisms with complex cellsKingdom:AnimaliaPhylum:Chordata Having a hollow dorsal nerve cord and flexible skeletal rodSub-Phylum: Vertebrata Having a backboneClass: Aves (Birds) Order:Strigiformes (Owls)
order Strigiformes • divided into two families: • the typical owls, Strigidae • barn-owls, Tytonidae largest: Eurasian eagle owl (left) smallest: least pygmy owl (top)
distribution • found in all regions of the Earth except Antarctica, most of Greenland, and some remote islands • variety of habitats, from thick forests to open prairies.
owl body plan • large forward-facing eyes and ear-holes • permits a greater sense of depth perception necessary for low-light hunting • hawk-like, downward pointing beak • flat face • Facial disc - circle of feathers around each eye • the female is often up to 25% larger
hunting adaptations • exceptional vision • acute hearing • powerful talons and beak • ability to fly silently
owl vision- exceptional • binocular vision • far-sighted • unable to see anything clearly within a few inches of their eyes • prey can be felt by owls with the use of filoplumes, which are small hair-like feathers on the beak and feet that act as "feelers“ • far vision, particularly in low light, is exceptionally good
skeletal system • 7-9% of its total body weight • many bones are fused • some larger bones are hollow • neck has 14 vertebrae -allows the owl to turn its head up to 270 degrees • large flat sternum to support the large and powerful flight muscles • differs in the two families • wing bones are relatively long and surface area is broad for easy take-offs and effortless flight • large eyes are fixed in their socket • must turn their entire head
Owls feed early in the evening and regurgitate a single pellet approximately 20 hours after eating.
hawks, eagles and other raptors that swallow their prey whole • Some Owl species will partially pluck bird and larger mammal prey.
no crop • sac in the throat that serves as storage for food for later consumption • 2 parts to stomach
How do Owl Pellets form? The protein enzymes and strong acids which occur in the digestive tract of raptors do not digest the entire meal. The relatively weak stomach muscles of the bird don’t break the bones so most are found whole.
The owl pellets that you will be examining in this lab have been collected and STERILIZED from common barn owls. • YOU SHOULD STILL WASH YOUR HANDS THOROUGHLY WHEN WE ARE FINISHED EACH DAY!
OWL PELLETS AS MICRO-ECOSYSTEMS • clothes moths • carpet beetles • fungi • The black spheres about the size of periods (.) that are found in the pellets are the droppings of the caterpillars. • The larvae metamorphose near the surface of a pellet in cocoons made of fur.
Use bone charts to identify bones and prey. Microscopes and hand lenses will help.
Sample notebook entry Observations of non-bone material: light gray fur, fur not dense, 2 thin white feathers on outside, few pieces of straw found outside
