On the west coast N. leleupi is found in the intermediate and rocky habitats. All individuals observed were solitary and found at depths below 15 metres. N. leleupi is a predator feeding mainly on aquatic insects and crustaceans. These are located in the biocover on the rocks or in the cracks between them. A foraging N. leleupi covers a large terrain. It is not known if they have a specific feeding territory; also juveniles have been observed feeding on their own. Their solitary behaviour may explain their pugnacious attitude towards conspecifics in aquaria. Only ripe females are tolerated in the male's domain. Eggs, however, are deposited in the female's cave. In the lake a wandering male may therefore find a ripe female in her cave and spawn with her. In the aquarium N. leleupi forms a pair during the breeding period. Breeding pairs have not yet been observed in the lake but it is likely that the male stays with the female until the young are big enough to face the outside world on their own. In the aquarium the pair bond rarely lasts longer than one month.