What’s Monitored

Looking at microbiotic organisims - rock photo by Darienne Mc Namara

 

Macroinvertebrates Group 1: sensitive to pollution

DobsonflyDOBSONFLY
Dobsonfly larvae (Order Megaloptera) are often called hellgrammites.  They are commonly found in oxygen-rich water, and obtain oxygen through their skin. The filaments that are found along their sides help them to obtain oxygen from the water by increasing their surface area.  They are equipped with hooks on the end of their body which help them to hold onto stable objects (such as rocks) in moving water.

WATER SNIPEFLY
SnipeflyWater snipefly larvae (Order Diptera) live in clean, fast-flowing water, which is oxygen-rich.  Only one genus, Atherix, is found in Wisconsin streams.  The larvae live for about one year, then pupate in the soil along stream banks, and emerge as adults in early summer.

 

 

 

 

AlderflyALDERFLY
Alderfly larvae (Order Megaloptera) also have filaments along the sides of their bodies which help them to obtain oxygen from the water in which they live.  These macroinvertebrates are carnivores and may live in the water in their larval stage for one to four years before emerging as adults.

STONEFLY

Stonefly Like other Group 1 organisms, stonefly larvae (Order Plecoptera) are often found in fast-flowing water, to take advantage of the high amounts of dissolved oxygen that are present.  Stoneflies breathe through their skin as well as with tufted-gills that are often located at the base of their legs (nearest their bodies).  Most times, stoneflies can be distinguished from mayflies by the presence of only two tail filaments (mayflies usually have three).


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