A Chain of Cranes

A recent trip to the Daintree region, Cape Tribulation, north Queensland resulted in a walk during the day on the Marrdja Boardwalk. This should not be missed if visiting the area. It's a meandering track through forest and mangrove. It would be perfectly safe and convenient during rainy periods because it is elevated and has a combined rubber and wood surface so you won't slip or get muddy. You can see an assortment of mangrove biota including a variety of trees and shrubs and crabs and fish.

While most people were concentrating on Fiddler Crabs, fish and the like, I looked up and discovered chains of craneflies (family Tipulidae).

This is not the best photo I have ever taken but it shows three flies out of about 20 that were attached to one another by their tarsi. I saw a number of these chains and many were waving in the windy conditions making photography even more difficult. But what was the point? What were they doing?

Any comments?