Larval development and production by the net‐spinning caddis,Polycentropus flavomaculatus(Pictet) (Trichoptera), in a recirculating stream channel

Publisher Website
Google Scholar
Abstract
1. The gravel substratum of a recirculating stream channel, sited in southern England, supported a population of P. flavomaculatus larvae. A short summer generation was followed by an overwintering generation with extended periods of recruitment and pupation. 2. The highest population density estimate (20,515 m‐2) was recorded during January. 3. Pupae were found in comparatively low numbers and in all months except October, November and December. 4. Estimates of production for P. flavomaculatus larvae, in terms of unpreserved dry weight, gave values of 14.57 g m‐2 (Allen curve) and 17.64 g m‐2 (Computational method) for the overwintering generation. The latter method gave a value of 2.73 g m‐2 for the summer generation. 5. Extended recruitment of young larvae and the long flight period recorded for this species may have obscured the presence of a fast growing, short, summer generation in other populations.