Birds part B Flashcards
During flight metabolic rate increase by how much?
10xBMR
Birds have how many chambers in the heart?
4 chambered heart, good for circulation, high blood pressure as well
Crop?
Storage chamber - food passed on for digestion or regurgitated for young
Proventriculus
Enzyme production: site of pellet formation in owls
Gizzard
Muscular chamber line with rough keratin (contains sandy grit (ingested by birds)
Excreted uric acid goes into
the cloaca
Excess water is reabsorbed by
The cloaca
Endothermic
Use metabolic hear to maintain a warm constant body temp
ectothermic
Use environmental temperature to regulate body temp
5 ways for thermoregulation warming
Shivering, Feathers, posture, Thermal counter current, Communal roosts (social behavior)
thermoregulation for cool 3 ways
evaporation, Panting Gular Flutter
Poster (spreading of the wings)
radiation
2 ways for bird senses
Vision is a dominant sense
Hearing (owls have two asymmetrical ears)
defining characteristics for migration
Seasonal and large numbers of individuals
Movement away from a natal area for migration
Dispersal. solitary and new location unpredictable
Movement away from a good poor area
Irruptions. Not annual and unpredictable
Birds migrate when
Benefits are higher than costs
Modes of migration (5 in total)
Flight pattern Time of day Flight mode length of migration Completeness
Flight pattern?
Non stops and hops
Time of day migration
Diurnal migrants -using thermal wings and updrafts
Nocturnal migrants - 1/2 hour before sunset because its cooler and air less turbulent
Flight modes
Soarers - flight concentrated in mid - day when thermals occur
powered flight - often crepuscular (star before dawn)
Orientation in migration is achieved by
Sun compass, star compass and magnetic compass
Navigation in migration is achieved by
Coast lines, mountain ranges, large rivers
Natal dispersal
The first movement away from the nest area (high mortality)
Breeding dispersal
Movement of adults between different breeding locations
