If you throw them in the canals, the fish generally ignore them. In late afternoon, feeding groups of lubber nymphs begin congregating and climb up onto the trunks of trees or whatever tall vegetation they can find. Clusters of thousands can sometimes be found. When fully grown, they moult into the reproductive, adult stage, and undergo a dramatic color change. The first adults start appearing in early summer.
Males spend inordinate amounts of time getting laid.
They climb onto females and ride them around, often with some resistance by the female. These behaviors are especially energetic when a rival male is trying to dislodge the current rider. These behaviors are often accompanied by flashing of the bright red wings and buzzing sounds produced by the wings. The males will often stay on the females until they lay eggs underground, as this female is doing.