Lecture 18

Question 1

what is the tradeoff with incubation?

Answer 1

tradeoff between few long recesses and many short recesses because rewarming eggs takes a lot of energy

Question 2

parents do not only insulate eggs, but instead use what?

Answer 2

conduction between eggs and own body to control egg temperature

Question 3

Transfer of heat to eggs is faciliated by what?

Answer 3

brood patch

Question 4

whats a method that mallee fowl and brush turkeys use instead of incubation from themselves?

Answer 4

moundbuilders! pile up vegetation heated by fermenting vegetation. Lay clutch of eggs. Test temperature every now and then

Question 5

is it now thought that incubation costs energy?

Answer 5

yes! costs more than basal metabolic rate! additionally cost with reduced time to forage

Question 6

Ability to leave eggs depends on what?

Answer 6

climate, predation pressure and number of parents

Question 7

length of incubation bouts may vary with what?

Answer 7

body contion, or with ambient temperature.

Question 8

what would be the difference in reccess during mid day of nests covered by vegetation (shaded) vs bare? white ptarmigan

Answer 8

bare would not take recesses during mid day whereas shaded ones did.

Question 9

whats the benefit of biparental incubation?

Answer 9

allows nearly constant attendance, allows the parents tto forage for themselves in alternating shifts and keep up their body condition

Question 10

what bird is an extreme example of female only incubation with males feeding them?

Answer 10

hornbill

Question 11

what is the disadvantage with an increase in number of visitation to the nests?

Answer 11

attracts predators!

Question 12

why do tropics have higher nest predation risk then temprate?

Answer 12

more predators in tropics

Question 13

Incubation feeding rates are higher at what nests?

Answer 13

cavity type nests

Question 14

Ptarmigan took more recesses as what started to decline during incubation

Answer 14

their body conditions

Question 15

what happened when they gave 5 diff species a stuffed hawk or squirrel?

Answer 15

change in incubation feeding, signficantly dropped. So they are awarre of the risks

Question 16

species with more vulnerable nest sites responded what way to increased predation risk?

Answer 16

more strongly. They decreased incubation feeding and increased nest attentiveness

Question 17

Do energetic demands constrain incubation scheduling in a biparental species?

Answer 17

yes, tested on sandpipers! suggests sandpipers would be more attentive to nests if they could but are forced to take recesses because of their own loss of energy. As well they increased when they could and took less trade offs with bi parent because this reduced predation attention

Question 18

in long lived ancient murrelets the incubation shift was correlated with what?

Answer 18

correlated between pair members. If the females had a short shift, so would the male

Question 19

In ancient murrelets what were the 2 main important factors that deterined foraging behaviour?

Answer 19

wind and tide height.

Question 20

what is the difference between a small bird incubation recesses and a long lived bird?

Answer 20

passerines are often off the nest much ore frequently throuhgout the day. short and rapid visists

Question 21

Incubation period:

Answer 21

The time required for the embryo to develop

Question 22

incubation period is related to what?

Answer 22

egg size and development. Precocial takes longer and larger eggs take longer.

Question 23

whats the tradeoff between hatching precoially vs long incubation period?

Answer 23

long risk of exposure of the eggs to predation

Question 24

is there a positive or negative correlation between relative egg mass and embryonic period?

Answer 24

positive

Question 25

In woodpeckers why is the egg tooth retained by nestling until near fledgling?

Answer 25

helps the parents to find gapes in the dark

Question 26

what else other than an egg tooth helps the bird break out of the egg?

Answer 26

hatching muscle

Question 27

Synchronous hatching:

Answer 27

begin incubation with last egg laid and eggs hatch synchronously

Question 28

Asynchronous hatching:

Answer 28

begin incubation sometime before last egg and young hatch over a period of hours or days (barn owls)

Question 29

why is hatchying synchrony important?

Answer 29

for determining allocation of parental care between sibilings

Question 30

why is hatching synchronously important for grouse and ducks?

Answer 30

nest sites are out in open and vulnerable so as soon as the offspring can leave as a group they are likely to survive better. Acheived through delaying incubation onset and talking eggs

Question 31

what are the 6 categories of hatchling development?

Answer 31

1. Superprecocial (moundbuilders)
2. Precocial (ducks, shorebirds, grouse)
3. Subprecocial (grebes, rails, cranes, loons)
4. Semiprecocial (gulls, terns, auks, penguins)
5. Semialtricial (herons, hawks, owls)
6. Altricial (songbirds, woodpeckers and parrots)

Question 32

superprecocial:

Answer 32

young are compeltely independent at hatching; no parental care

Question 33

precocial:

Answer 33

• young leave the nest soon after hatching and follow parents. Young can feed themselves almost immediatly.

Question 34

subprecocial:

Answer 34

young leave the nest at hatching and follow parents. Young are fed by parents or at least shown where food is.

Question 35

Semi precocial:

Answer 35

young are somewhat mobile at hatching but remain at the nest and are fed by their parents.

Question 36

semi altricial:

Answer 36

young not mobile at hatching and are fed and brooded by parents. Eye are open at hatching or within a few day

Question 37

altricial:

Answer 37

young are naked, blind and heloless at hatching. only have a begging reflex.

Question 38

is it precocial or altricial that is thought to be more primitive?

Answer 38

precocial

Question 39

what do the energy demands look like for precocial birds?

Answer 39

put a premium on the ability of females to obtain abundant resources before laying and must produce energy rich eggs to support the greater in-egg development of the chicks.

Question 40

females of altricial species do not have such large nutritional demands before egg laying but what are the tradeoffs?

Answer 40

they must be able to find sufficient food to fledge young quickly because they are extremely vulnerbale to predation. Precocial young can avoid predation to some extent