Owl pellet dissection
Download
1 / 14

Owl Pellet Dissection - PowerPoint PPT Presentation


  • 127 Views
  • Uploaded on

Owl Pellet Dissection. Five species of owls live in or pass through Maryland. Barn owls Great Horned owl Barred owls Eastern Screech owl Northern Saw-whet owl. Owls of Maryland. Barred Owl. Owls have special adaptations that enable them to hunt at night.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Owl Pellet Dissection' - hazelle


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Owls of maryland

Five species of owls live in or pass through Maryland.

Barn owls

Great Horned owl

Barred owls

Eastern Screech owl

Northern Saw-whet owl

Owls of Maryland

Barred Owl


Adaptations as predators

Owls have special adaptations that enable them to hunt at night.

Their eyes are large and fixed, with binocular vision and good depth perception.

Because owls are unable to move their eyes, they have developed an incredibly flexible neck that allows them to turn their head 270 degrees in both directions.

Their eyes are also extremely light sensitive, allowing them to see well at night.

Adaptations as predators

Barred Owl


Owls as predators

Owls rely on night.silent flight to surprise their prey.

The shape of the owl’s flight feathers muffles the sound wind makes as it flows past them.

These are all perfect adaptations for finding and catching prey at night, and explain why owls have become the most efficient “hunters of the night”.

Owls as predators

Saw-Whet Owl



Owl pellets

Predatory mammals such as bobcats and wolves have teeth to grind up bones and claws, and, a digestive tract adapted to pass these ground parts.

Owls, on the other hand, do not have teeth for grinding and cannot pass whole bone and claws through their digestive tract safely.

The protein enzymes and strong acids that occur in the digestive tract of raptors do not digest the entire meal.

The relatively weak stomach muscles of the bird form the undigested fur, bones, feather etc. into a bolus (or wet slimy pellets).

The undigested portions may include beaks, claws, scales, or insect exoskeletons. This type of material has little nutritional value and must be passed from the body.

Owl Pellets


Owl pellet dissection 1324713

The owl pellets that you will be examining in this lab have been collected and fumigated from common barn owls (Tytoalba).

Owl pellets themselves are ecosystems, providing food and shelter for communities that may include moths, carpet beetles and fungi.

Moth larvae are frequently abundant in pellets, feeding on fur and feathers. 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.


Owl pellets1

Ecologist examine owl pellets to estimate the diversity of prey species

The contents are a direct indicator on

What the owl has fed upon.

Species richness

Species abundance

Important information for species management and protection

Owl Pellets


Species diversity has two components
Species diversity prey specieshas two components:

  • Species richness: how many different species are present in a habitat

  • Relative abundance: total number of individuals of each species present given in % of total.


Species diversity has two components1
Species diversity prey species has two components:

  • Species richness: how many different species are present in a habitat

  • Relative abundance: total number of individuals of each species present given in %

2003

1. Red Maple

33%

2. Black Gum

18%

3. Sweet Gum

17%

4. Oaks

14%

5. American Holly

8%

6. Loblolly Pine

6%

7. American Beech

4%