12.4. Calypte anna: Anna’s Hummingbird http://www.ck12.org
brain-to-body size of any bird, giving them a phenomenal memory. The pneumatic bones of an Anna’s hummingbird
are hollow and only air-filled.C. annahas a four-chambered heart. That is very important since hummingbirds have
such a high metabolism. Their respiration is in two cycles, unlike mammals who only have one cycle. These two
cycles provide huge amounts of air and helps remove excess body heat. During the first cycle, they inhale air from
the posterior air sacs and then exhale air from the posterior air sacs to the lungs. When the air enters the lungs, this is
the oxygen/carbon dioxide exchange site. During the second cycle, air inhaled from lungs go into anterior air sacs.
From the anterior air sacs, air is exhaled out of the primary bronchus. The primary bronchus is one of the two main
air passages that branch from the trachea.
Digestion is a very important part of the bird’s body. The crop is an enlarged extension of the the esophagus. Here
they store food for digesting later or to feed their chicks. The proventriculus is the anterior glandular stomach that
produces gastric acids and digestive enzymes, just like in our stomachs. After the proventriculus, the food goes to
the gizzard. The gizzard is the posterior muscular stomach. Its main purpose is to grind food. The gizzard may need
to be aided with rocks or stones, called gastrolith.
Behavior
Anna’s hummingbirds are not social animals. They will dive at anything that comes near their territory. The Anna’s
hummingbird migrate in the fall and spring. To conserve energy, the Anna’s hummingbird are active during the day
and become torpid at night. Male Anna’s hummingbirds have a special mating ritual. The male flies to a height of
130 feet, and plummets down to the ground pulling up at the last minute, making a beautiful sound through their tail
feathers.
SeeThe Courtship of Anna’s Hummingbird (Britannica.com)at http://www.youtube.com/watch?v=NMErQg0dFDs
for a further description of this mating ritual and these birds.
References
- http://www.naturebytesvideo.com
- "All About Birds."Anna’s Hummingbird, Identification,. N.p., n.d. Web. 12 Mar. 2013.
- Bailey, Dave. "What Is a Bird?" San Diego: Mission Trails Regional Park Trail Guide Training Program,
2008. - Book of North American Birds. Pleasantville, NY: Reader’s Digest Association, 1990. Print.
- Calypte Anna —Details.Encyclopedia of Life. N.p., n.d. Web. 26 Mar. 2013.
- Chinery, Michael.The Grolier Illustrated Encyclopedia of Animals. Vol. 2. Danbury, CT: Grolier Educational,
1994. Print. - Peterson, Roger Tory.Peterson Field Guide to Birds of Western North America. 4th ed. Boston: Houghton
Mifflin Harcourt, 2010. Print. - Sibley, David.The Sibley Field Guide to Birds of Western North America. New York: Knopf, 2003. Print.
- Udvardy, Miklos D. F.Field Guide to North American Birds. New York, NY: Knopf, 1998. Print.
Attribution
Authors
- Hilary Castaneda
- Victoria Nguyen