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#Question id: 12428


Flycatcher birds that migrate from Africa to Europe feed their nestlings mostly with moth caterpillars. The data presented show the mean dates of egg laying, hatching, and fledging of flycatcher young, and the 1980 and 2000 peak mass of caterpillars.

Why are ecologists  concerned about the shift in  date from May 28 in  1980 to May 15 in  2000 of the caterpillar peak mass?

#Unit 10. Ecological Principles
  1. The  caterpillars will  eat  much of  the  foliage of  the  trees where flycatchers nest, and  their  nests will  be more open to predation.
  2. The earlier hatching of caterpillars will compete with other insect larval forms on which the flycatchers also feed their young.
  3. The flycatcher nestlings in 2000 will miss the peak mass of caterpillars and may not be as well fed.
  4. The flycatchers will have to migrate sooner to match their brood-rearing season with the time of caterpillar peak mass.