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Post-Treatment Monitoring

Adult Insects

During the summer of 2007, adult insects were seen around Diamond Lake in varieties and numbers that had not been present with the high tui chub population. Instead of quivering due to tui chub surfacing, Diamond Lake rippled with the impacts of adult bugs hitting the surface. Emergent insects flew from the lake in such large numbers that their shed skins collected into windrows, even visible from the air. 

Dragonflies and damselflies could be seen emerging from larvae to adult stage on rocks and vegetation near the lake, then darting around the lake hunting smaller insects.  Midges formed clouds so thick and numerous that it was often a challenge to talk anywhere outside without inadvertently eating a few. 

A UV light trap was used to collect emergent insects from around the lake at night.  Many of the benthic organisms have adult life stages above water surface (i.e. midges, dragonflies, damselflies). By sampling the adult aquatic insects, biologists learned which insects were successful in their larval and pupa stages underwater and could reproduce, continuing the cycle. 

Dragonfly Nymph to Adult Belastomid

Dragonfly Nymph to Adult

Dragonfly adults clinging to nymph exoskeletons as wings harden

Dragonfly nymph to adult Belastomid a large fish eating insect captured during random surveys 2007
UV Light Trap with moths and midges UV light trap with attracted moths
UV light trap overloaded with moths and midges UV light trap with attracted moths
dragon fly dragonfly nymphs swept into outmigrant trap by lake outflow 2007
Dragonfly poses in front of Thielson dragonfly nymphs swept into outmigrant trap by lake outflow 2007

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