Lecture 12 Flashcards
(32 cards)
what are the types of migration?
- Local. Loons from lake in summer to ocean in winter
- Long distance: Trans equatorial or nearly so. (Barn swallow)
- Short distance: stays within the same hemisphere, withdraws from the harshest regions near the poles (Northern flickr)
- Partial migration: within the same population, some individuals migrate but others are sedentary (lesser black backed gull)
Ultimately the distance the bird needs to migrate is associatd with the type and accessibility of —–
food
They often follow ———
landmarks
what is the importance of the bay of Funday?
about 75% of the world population of semipalmated sandpipers stops at the bay of funday for the mudshrimp which contain a large amount of fatty acids.
The bay of funday hosts more than how many shorebirds?
500,000
what bird has the greatest annual distance in migration?
Arctic Tern
Longest non-stop flght record holder is….
Bar-tailed godwits from alaska to new zealnd
what are some techniques and the data they give for studying migration?
- Band recoveries –> location
- Flight calls –> Timing
- Doppler radar –> timing
- Radio temetry –> full year data (timing, route, locations)
- Satellite telemetry –> full year data
- GPS –> full year data
- Light level geolocation –> full year data
- Intrinsic measures –> habitat and location
animal tissues reflect the isotopic composition of what?
their supporting food web
Hydrogen &D is found where and reflective of what?
found in feathers and is reflective of where the feather was grown. Heavier values mean it was further south and lighter values were north
what did the study of red-eyed vireos migration show?
the body cindition affects the migratory route chosen. Bad body condition took a stop route but longer route. Good body condition had an orientation directly south. Assentially take a short cut across the gulf of mexico
Blackpoll Warblers rely on what?
trade winds.
what is the leap frog migration shows by the fox sparrow?
where the northern most populations winter in the southern most.
what is the difference in wintering habitats between male and females?
males often winter farther north than females
how do juvenilles winter differently than adults?
often winter farther south in some species
what are the 3 factors that go into the female, male and juvenille differences?
- High migration mortality favors juvenilles flying short distances.
- Males winter farther north to return to breeding ground first and claim the best territories.
- Survival incrwases with decreasing latitude so females, unaffected by the first 2 factors, take advantage of higher survival and winter the farthest south.
V flight:
thought to be energetically advantageous
what did the study that impanted heart rate monitors on pelicans discover about being the leading individual or others?
Formation was reduced compared to pelicans alone. The heart beat was higher in first individual and declined for those who were following.
what are some example of birds changing their migration to diurnal or nocturnal?
- Soaring birds depend on thermals for soaring and will fly when these currents occur,
- Passerines can avoid predators and have calmer winds at night.
A study moved a bird off migration route and tried to observe if they would change their orientation, what happened?
they discovered they they can asses their angle and go in the right direction, they have a true navigation ability.
Birds navigate using a number of cues such as…
- visual cues- landmarks
- Accurate sense of time
- Earths magnetic field
- Celestial cues- sun by day, stars at night
when pigeons had frosted glasses placed over their eyes could they still find home?
Yes they could!
what happens to starlings on cloudy days?
starlings are day time migrators and can orient themselves via sun but on cloudy days this createa a challenge
is navigating by stars an innate or learned behaviour?
young birds must see the night sky within 1 month of hatching to learn the rotations of the stars
