Abstract
In the Greater Manchester area 2017 was an unusual year for nymphalid populations, the first in a thirty year period when the numbers of records of both Vanessa atalanta and Polygonia c-album (single egg-layers) exceeded those of Aglais urticae and A. io (large batch egg-layers). Annual abundances in Greater Manchester of these nettle-feeding nymphalids has revealed that the members of these two groups of species correlate with one another more closely than with either species of the other group. It is suggested that the mode of egg deposition (single egg-layers versus batch-layers) is involved in associations of changes in abundances of the nettle-feeding nymphalids. Other factors in life history may also be involved and are discussed (autumn adult food resources and larval host use). The same pattern is not found in pierids which differ in over-wintering mode and host plant condition. The costs and benefits of different egg-laying strategies are considered in relationship to changing abundances of species.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have