Batgung

These butterflies are everywhere at the moment. It seemed strange to me, given that it's the coldest time of year. However the LCSD's website description of the butterfly says it's normal:

Medium size. Very common and can be seen all year round. The population of this butterfly species will suddenly increase in winter. It is much less frequently seen in summer.

It doesn't say how or why the population suddenly increases in the winter though. Does the chrysalis wait until the temperature drops to a certain level before the butterfly emerges? Or do the butterflies hide away somewhere until it gets cool enough?

This site says:

They tend to be a cooler climate group and in the tropical areas of their distribution they habitat is generally in the mountainous areas, only coming down to lower altitudes in the cooler winter months.

So maybe they are all lurking around the top of the Peak, then swoop down when the cool weather arrives?

MrB