Flycatcher birds that migrate from Africa to Europe feed their nestlings a diet that is almost exclusively moth caterpillars. The graph in Figure 43.3 shows the mean (peak) dates of bird arrival, bird hatching, and caterpillar season for the years 1980 and 2000.
A) The caterpillars would have eaten much of the foliage of the trees where flycatchers would have nested, rendering their nests more open to predation.
B) The earlier hatching of caterpillars would compete with other insect larval forms that the flycatchers would also use to feed their young.
C) The flycatcher nestlings in 2000 would miss the peak caterpillar season and might not be as well fed, leading to population reductions.
D) The flycatchers would have to migrate sooner to match their brood-rearing to the time of peak caterpillar season.
Answer: C
Why were ecologists concerned about the shift in the peak caterpillar season from June 3, 1980 to May 15, 2000?
A) The caterpillars would have eaten much of the foliage of the trees where flycatchers would have nested, rendering their nests more open to predation.
B) The earlier hatching of caterpillars would compete with other insect larval forms that the flycatchers would also use to feed their young.
C) The flycatcher nestlings in 2000 would miss the peak caterpillar season and might not be as well fed, leading to population reductions.
D) The flycatchers would have to migrate sooner to match their brood-rearing to the time of peak caterpillar season.
Answer: C