Cased Chironomid Larva Respiration and Movement

In my last post I talked about how chironomid larva that build tubes or cases use body undulations to maximize oxygen intake. This behavior is used by not just chironomid larva living in the hypoxic zone on the bottom, but also by chironomid and caddisfly larvae that build portable cases. They do this when  oxygen levels are low or they need to refresh the stagnant water in their case. 

This video shows how a chironomid (midge) larva undulates in its tube to circulate water to aid in respiration. This particular genus (Cricotopus) builds a portable tube, while other chironomid groups construct more extensive stationary tubes in the mud. The video also shows how chironomid larvae that build portable tubes move by reaching out and pulling themselves forward. In the final scene, the midge larva gets caught on a strand of vegetation and uses a small pebble to leverage itself up and over.