The tiny but abundant midges collect food by all
of these methods: shredding, collecting, scraping,
eating other animals and even feeding directly on
wood. The complexity of the physical
environment-rocks, woody debris, rooted vegetation,
soft sediment-as well as the varied food sources
are important factors in the increase in numbers
and diversity of the invertebrate community.
By now, the stream is getting warmer and is
suitable to more species but may be too warm to
support some, such as trout. This wider range of
species finds shelter and food in the
ever-increasing variety of habitats.
Most likely, the stream is deeper, with a
regular pattern of riffles, runs, and pools. These
provide critical habitat for minnows, darters,
bass, sunfish, walleyes, bullheads and suckers.
These fish, depending on the size and species, may
feed at various times at all levels of the food
chain, from phytoplankton, to aquatic insects, to