Tytonidae

1
Tytonidae

• Barn Owls

Presentation by Dustin M. Prebilic
2
Diversity

• Tytonidae includes two extant genera
• Tyto (barn owls, masked owls)
• Phodilus (bay owls)
• Within these genera, there are 16 species, though
  taxonomy is frequently being revised.
• Greatest diversity in tropics, but not much is
  known about many of the species except the
  well-studied Tyto alba, the common barn owl.

3
Bay Owls Phodilus badius
Oriental Bay Owl
Sri Lanka Bay Owl
Masked Owls Tyto novaehollandiae
Tasmanian Masked Owl
Masked Owl
4
Barn Owls Tyto alba
5
Distribution and Habitat of Tyto alba

• One of the most widespread bird species,
  occurring on all continents except Antarctica.
• Prefers open country (such as farmlands) and
  usually hunts at the edge of forests.

6
Characteristics Separating them from Strigids

• Heart-shaped facial disk
• Elongated, but compressed bill
• Relatively smaller eyes
• Most will carry prey in their beak instead of
  with their talons like most owls
• Head morphology aiding in even better hearing

7
Specialized Hearing Adaptations

• Heart-shaped facial disk is made of stiff
  feathers that help amplify/collect sounds toward
  the ears.
• Silent wing feathers prevent their own hearing
  from being interrupted (as well as preventing
  being heard by prey).
• Ears are asymmetrical, giving them exceptional
  3-dimensional hearing.

8
Asymmetrical Hearing

• Diagram on page 194 of text.
• Left ear is set higher than the right, with the
  ruff facing downward to increase sensitivity to
  sound below the horizontal plane. Right ear is
  positioned lower with ruff facing upward.
• While humans bilateral ears are accurate at
  locating sounds horizontally, barn owls can
  locate sounds 3 times as well in the vertical
  plane just by tilting their heads up or down.
• Able to locate sounds within 1 degree in both
  horizontal and vertical planes.
• This allows them to accurately locate and catch
  prey even in total darkness.

9
Figure 7-6