Lecture 28- Bird Adaptations

Question 1

What are some different strategies for birds living in the north?

Answer 1

• Permanent residents
• Short distance migrants
• Long distance migrants

Question 2

What types of bird species are migrants because they rely on open water that freezes in the winter?

Answer 2

• Dabbling ducks
• Diving ducks
• Shorebirds
• Warblers

Question 3

Tundra swans use which migration corridor?

Answer 3

Atlantic flyway

Question 4

Smiths longspur use which migration corridor?

Answer 4

Mississippi flyway

Question 5

Gloden eagles use which migration corridor?

Answer 5

Central flyway

Question 6

Brants use which migation corridor?

Answer 6

Pacific flyway

Question 7

What are some pros to being a permanent resident as a bird?

Answer 7

• Low competition
• Energy espense to fly
• Ability to respond to changes in food

Question 8

What are some cons to being a permanent resident as a bird?

Answer 8

• Must survive cold
• Low available resources

Question 9

What are some pros to being a migrant as a bird?

Answer 9

• Dont have to tolerate cold
• Gain access to nutrient rich foods

Question 10

What are some cons to being a migrant as a bird?

Answer 10

• High energy expenditure
• Inability to respond to shift in food availability

Question 11

Describe population limitations in migratory birds

Answer 11

Question 12

What are some benefits for birds to migrate north?

Answer 12

• Long photoperiod = allows more time for foraging
• Abundant food (but limited over time) = can be unpredictable depending on the weather
• Reduced competition
• Reduced predation

Question 13

What are some issues with birds breeding in the north?

Answer 13

• Short breeding season = reduced feeding, growth and reproduction time
• Cool and variable temperatures
• Diet flexibility
• Many birds lay eggs directly onto cold ground = problem with keeping eggs warm

Question 14

What are some general patterns of bird breeders?

Answer 14

• Adaptation for breeding early (short interval between arrival and egg laying = already mated)
• Short, synchronous breeding period (hatch at peal nutritional value = predator swamping)
• Life history stategies (Increased clutch size = fewer clutches)

Question 15

What are some general patterns seen in northern bird breeders?

Answer 15

• Incubation and nesting strategies (down in nest, frequent egg turning, colony nesting in inaccessible sites)
• Rapid development of young (precocial young = born highly developed, short development to feldging)

Question 16

What are the two types of breeding strategies in birds?

Answer 16

1. Income breeders
2. Capital breeders

Question 17

What is an income breeding strategy?

Answer 17

Nutritional resources for breeding obtained on breeding grounds

Question 18

What is a capital breeding strategy?

Answer 18

Nutritional resources accumulated elsewhere and stored in body, brought to breeding grounds

Question 19

Bird breeding strategies exist on a _______

Answer 19

Continuum

Question 20

Capital breeders are best for?

Answer 20

For a stochastic environment

Question 21

Describe some characteristics of capital breeders

Answer 21

• Accumulate body fat for migration
• Food may not be available during laying
• Some species ride the green wave (take advantage of advancing green up)

Question 22

Describe the effects of climate change on breeding strategies

Answer 22

• Strength of selection on breeding strategies change as a result of climate change
• Income breeders affected by phenological mismatch (reliant on resources that may not be there)

Question 23

What must permanent bird residents to to survive?

Answer 23

• Must withstand winter temperatures
• Must find enough food
• Very few species are arctic residents

Question 24

What are some behavioural adaptations in birds to the cold?

Answer 24

• Adjust feeding strategies
• Marine birds migrate to polynya (accessibility to fish in open water)
• Burrowing under snow (traps warm air and protects from winds)
• Huddling or roosting

Question 25

What are some morphological adaptation to the cold in birds?

Answer 25

• White coloration (camoflauge and avoid predation)
• Fluff feathers (traps air next to body)
• Feathered legs (extra layer of insulation for exposed limbs)

Question 26

What are some physiological adaptations for the cold in birds?

Answer 26

• Nightly torpor to avoid energy use
• Countercurrent blood flow (heat remains in the core and allow feet to freeze, just need to keep them oxygenated)