Presentation on theme: "BARN OWLS. Critical Thinking You are a wildlife biologist. A group of farmers has come to you for help. The owl population in the area has increased significantly."— Presentation transcript:
Critical Thinking You are a wildlife biologist. A group of farmers has come to you for help. The owl population in the area has increased significantly over the last 2 years. Half the farmers believe that owls are killing their chickens, especially the young chicks, for food. They want a bounty placed on owls to encourage people to shoot and kill them.
Critical Thinking The other half of the farmers say that the more owls that are around, the fewer mice and rats they see in their grain storage bins and less grain is eaten by the rodents. They want the state wildlife service to import even more owls into the area. As a wildlife biologist, how would you collect data to solve this problem?
Think, think, think... In order to answer that question, it might be helpful to learn more about the Barn Owl. Let’s take a closer look at this interesting bird!
What Does the Barn Owl Look Like? Heart-shaped Face Small Eyes Long Legs White Chest and Underside No Ear Tufts
Where Do Barn Owls Live? Barns or Silos Hay Stacks Palm Trees Abandoned Buildings Rock Walls Holes in Cliffs
Barn Owls are Predators A predator is an animal that catches another animal for food. Some predators include: Hawks Eagles Owls Snakes Lions Alligators
What are Prey? The prey are animals that get eaten by predators! Some prey might include: Small insects Rats Rabbits Skunks Birds
How Does the Barn Owl Fit into the Food Chain? All living things depend on each other to live. The food chain shows how some animals eat other animals to gain energy for survival. Grasshopper eatsgrass. Field mouse eats grasshopper. Barn owl eatsfield mouse.
How the Food Chain Works: Hawk gets energy from eating the snake. Snake gets energy from eating the grasshopper. Grasshopper gets energy from eating grass. Grass gets energy from the sun to make its own food (photosynthesis)
Barn Owls are Raptors Raptors are birds that catch their prey with the long claws on their feet. These claws are called “talons”. Raptors also have: - Hooked beaks - Excellent eyesight - Strong legs and feet Hawks, eagles, and owls are raptors. talons sharp beak
How do Barn Owls Hunt? Barn owls are predators, which means they must kill other animals to survive. They use their amazing eyesight to hunt at night. But... on nights when it is too dark to see very far, they can find prey by listening. Owls ears are so precise, they can catch a mouse in total darkness, just by hearing its footsteps in the grass!
More on Hunting The barn owl’s wings are made of downy feathers, which muffle the sound as they approach their victim. They fly low and capture their prey with their feet. They rip through the back of the skull with their bill. They prey is swallowed whole.
Barn Owl Catching Prey
What do Barn Owls Eat? Mice Shrews Voles (meadow mice) Field rats Insects Small rabbits Other small animals (chickens, maybe?) shrew vole
What is an Owl Pellet? Owls swallow their prey whole in one big gulp. Since they can’t digest bones and fur, they cough up these parts of the meal into a compact mass called an owl pellet. The pellets are approximately two inches long and brownish in color.
1st2nd3rd 4th5th 6th How are Owl Pellets Made?
How to Dissect an Owl Pellet STEP #1: Tear open your owl pellet very gently. Be careful not to break any whole bones! You can use forceps and a probe or... You may pull the owl pellet apart with your fingers.
Dissecting an Owl Pellet STEP #2: Separate all the bones from the fur with forceps. When you think you have all the bones out, rub the fur between your fingers. If you feel anything hard, it’s a bone. You need all of them!
Dissecting an Owl Pellet STEP #3: Discard the fur. Take a clean sheet of paper and fold it into six sections.
Label your Paper STEP #4: Skulls and jaws Ribs Vertebrae Hips/shoulders Legs Feet and toes
Identifying your Bones Using a diagram of various skeletons, try to identify the bones. It will be helpful to identify the skull and jaw bones first.
Classify your Bones Arrange the bones on your paper in the appropriate box. Can you tell how many animals are found in your owl pellet? remains of 1 skeleton
Identify the Animal Types Could the Barn Owl have eaten a... Chicken? Mouse? Shrew? Vole? Rat? Mole? chicken skeleton
Critical Thinking How were you able to identify what type of animal your Barn Owl ate? Did the Barn Owl eat a chicken? What should the farmers do about the Barn Owls?