Dr Richard White sets a mudfish trap in a South Westland rainforest tree tip-up pool. The fern-covered root wad of the fallen rimu tree that created the pool is visible behind. The depression created by the fallen tree has filled up with tea-coloured water from the forest. The mudfish probably feed on invertebrates which fall from the forest above. Although the pools are not normally not connected by standing water, brown mudfish are able to colonise them by travelling through the forest - either at times of high rainfall or by moving through the moss and mud.