pop ecology of warblers of northeastern coniferous woodland- R.Macarthur

Question 1

what are the 5 warbler species?

Answer 1

• cape may, myrtle, black throated green, black burnin, bay breasted

Question 2

the warblers are congenial what does this mean?

Answer 2

similar size and shape

Question 3

what do they eat/what are they?

Answer 3

are insectivores

Question 4

what was the aim?

Answer 4

to determine factors controlling species abundances and prevent all but one from being exterminated by competition

Question 5

what 3 things occur independently of density?

Answer 5

catastrophes, storms, severe winter

Question 6

what 2 events are density dependent?

Answer 6

food shortage, nesting holes

Question 7

when are interspecific relations important?

Answer 7

when density dependent events play a role

Question 8

what did volterra, gause and Grinnell propose?

Answer 8

if species requirement similar one 1 species can persist

competitive exclusion

Question 9

what isn’t always sufficient/necessary to prevent competition and permit coexistence?

Answer 9

differences in food and space

Question 10

where may birds emigrate to from reproductively suitable habitats?

Answer 10

to marginal habitats

Question 11

in a heterozygous habitat what may happen to a species?

Answer 11

may be eliminated from its preferred habitat

Question 12

in what 2 ways can you study limiting factors by?

Answer 12

1. artificially modifying single factors in the environment

2. compare populations in 2 regions which differ in abundance of the factors considered

Question 13

what happens to the warbler species when density dependent events are rare?

Answer 13

they increase

Question 14

if more runs of Increase or decrease are observed, what does an increase make the following change mire likely to be?

Answer 14

decrease

Question 15

how long of a cycle would be required for fluctuations if density independent events controlled population?

Answer 15

2.5yr

Question 16

when are cape may and bay breasted abundant ?

Answer 16

when an outbreak of spruce budworm (but will act as a limiting factor as is a food supply source)

Question 17

what does it mean because of the fact that 2 sympatric species have their populations limited by different factors?

Answer 17

that they limit their own growth more than others

Question 18

why were there differences in food type?

Answer 18

different feeding behaviours, manner of feeding, time of feeding, zonal characteristics

Question 19

what 3 sections were the branches divided into?

Answer 19

• bare/lichen covered base
• middle: old needles
• terminal: new needles/ buds

Question 20

why may some behaviour be invisible?

Answer 20

the forest is dense

Question 21

what was subjective?

Answer 21

the birds feeding habits

Question 22

in what 3 directions was the motion of birds recorded?

Answer 22

vertical, radial, tangential

Question 23

which direction did the cape may mainly move in?

Answer 23

vertical

Question 24

which direction did the black throated green and myrtle mainly move in?

Answer 24

tangential

Question 25

which direction did the bay breasted and black burnian mainly move in?

Answer 25

radial

Question 26

when is flight considered to be ‘long’?

Answer 26

if between different trees and greater than 25ft

Question 27

which 2 birds have longer flights than the others?

Answer 27

cape may and myrtle

Question 28

give 5 features of the myrtle

Answer 28

1. most varied/flexible feeding habit
2. most equal components of direction of travel
3. widely distributed feeding zone
4. tangential
5. 15-20ft

Question 29

give 8 features of the black throated green

Answer 29

1. restricted feeding habits
2. tangential
3. shortest interval between flights (seems most active)
4. rapid peering feeding
5. hop on white spruce
6. hovers under branch with food
7. noisy feeder
8. 15-20ft

Question 30

give 6 features of the blackburnian

Answer 30

1. high in trees
2. moves from base to tip of branch
3. hop on mat of foliage
4. rapid peering
5. radial
6. 30-50ft (upper branch)

Question 31

give 8 features of the bay breasted

Answer 31

1. restricted feeding habits
2. uses wings less
3. radial
4. from lichen base to tip
5. mainly in shade
6. same tree for long periods
7. rarely hovers
8. 10-15ft (lowest)

Question 32

all of the birds have similar bits but specifically what is the bill like of the cape may?

Answer 32

slender with semi tubular tongue

Question 33

what kind of bills do both black throated green and black burnin have?

Answer 33

vireo

Question 34

give 2 features of cape may

Answer 34

1. 40-50ft

2. near trunk on upper branch

Question 35

what is the behaviour like for defending against individuals of the sae or different species?

Answer 35

same

Question 36

how may a pop be prevented from breeding?

Answer 36

if unoccupied territories are absent

Question 37

since the budworm outbreak what has the bay breasted pop increased by?

Answer 37

5-7 fold

Question 38

what happens to territory sizes if pop increases?

Answer 38

decreases

Question 39

is inter/intra specific territory guarding weaker and what does it mean territoriality can do In these warblers?

Answer 39

inter- weaker

it can reduce competition and act as a stabilising factor

Question 40

which 2 species have larger clutches than the others and why?

Answer 40

cape may and bay breasted - budworm outbreak

Question 41

what species often destroys the nests?

Answer 41

red squirrels

Question 42

how can stability be increased?

Answer 42

have large clutches when food is abundant

Question 43

which bird completes its clutch first and which last?

Answer 43

first: cape may
last: bay breasted

Question 44

which birds may reach peak abundance sooner and nest earlier?

Answer 44

those catching insects at T zone and tree tops

Question 45

where may the birds migrate to In winter?

Answer 45

N.america

Question 46

how many winter overlaps were found in the 5 species?

Answer 46

10

2 per species

Question 47

in general is the warbler behaviour independent of environment/seasons?

Answer 47

yes, same In both seasons

Question 48

what 4 factors control pop size and which is likely to be the most limiting?

Answer 48

food, nesting sites, predators, suitable space- most likely

Question 49

what is the tree nesting warbler pop proportional to?

Answer 49

foliage volume

Question 50

which species is dominant at mature spruce ?

Answer 50

black throated green

Question 51

which species is dominant at old forests ?

Answer 51

blackburnian

Question 52

which species is dominant at lichen branches ?

Answer 52

bay breasted

Question 53

what means the species can coexist?

Answer 53

the difference in nesting time and habitat and food preference and zones

Question 54

which 2 species re seen as fugitive?

Answer 54

cape may and bay breasted

Question 55

what does the fact species differ in trait related to resources not mean?

Answer 55

doesn’t mean that competition is occurring or that it has evolved in evolution of trait

Question 56

no 2 species can coexist unless…?

Answer 56

• different resources
• same resource but at different times
• same resource but in different locations
• same place but different locations

Question 57

other than completion what may be another reasons they differ in resources?

Answer 57

due to being differentially sensitive to predators