Most of what is known about Limnogale's ecology and behavior stem from a small handful of studies, most notably those of Malzy (1965) and Benstead et al. (2001), much of which is summarized in Benstead and Olson (in press). Benstead et al. (2001) conducted radiotracking surveys of two radiotagged individuals at Ranomafana National Park, confirming many earlier speculations and adding several new observations on the natural history of the species. They found that Limnogale appears to be strictly nocturnal, foraging throughout much of the night (with occasional returns to burrows for rest periods) and returning to their burrows 60-90 minutes before sunrise; Captive individuals likewise avoided sunlight. Movement was always restricted to the same stream channel but was otherwise unpredictable. The majority of active periods were spent foraging in water, and captive animals displayed a consistent behavior wherein prey was located via tactile detection using the facial vibrissae (whiskers) during underwater foraging bouts lasting 10-15 seconds. The webbed hindfeet were used for propulsion with the tail acting as a rudder. Once encountered, prey items were seized in the mouth, brought to the surface, and immobilized with kicks from the hind feet. Once subdued, the prey was brought onto an emergent rock and consumed entirely. Before re-entering the water, individuals engage in assiduous grooming behavior, presumably to restore the insulative and/or buoyant properties of the fur.

Analysis of fecal samples indicate that Limnogale's diet includes small frogs, crayfish, small fish, freshwater crabs, and aquatic insects, with the latter comprising the bulk of the prey consumed by individuals in Ranomafana. Limnogale appears to be active throughout the year; individuals have been collected at or near Ranomafana in October, May, July, and August. Based on observations and museum specimens, young are believed to be born during December and January in litters of 2-3.

The single Limnogale burrow recorded by Malzy (1965) was located on a steep slope about 0.5 meters above the water level and had been dug horizontally into the bank, its entrance obscured by grass. Ten cm. in diameter, 17 cm. deep and lined with grass, it contained two juveniles. Although Benstead et al. (2001) were unable to locate the burrows used by the two radiotagged individuals at Ranomafana, they were able to confirm their location in similarly steep slopes above the stream channel. Considering all the available evidence, Limnogale is clearly tightly dependent on river and stream ecosystems, never straying far from water.

One final noteworthy aspect of Limnogale's behavior involves a fundamental law in biology. Limnogale is unique among Malagasy mammals in depositing its distinctive feces in prominent and exposed latrine sites. Favored latrine sites are usually large emergent boulders located in the middle of the stream channel, although downed trees are sometimes also used. Latrine site fidelity is evident; many sites at Ranomafana were used repeatedly over a 4-year period. Although the function of latrine sites is not known, it is likely linked to the semi-aquatic lifestyle of the species, as many ecologically similar mammals share this behavioral trait. As yet, we do not know whether latrine sites serve a territorial or other signaling purpose, or whether they are communal. However, it is clear that latrine sites offer golden opportunities for research on this otherwise secretive species (see following pages).

Limnogale home | Aquatic adaptations | Distribution | Natural History | Conservation | Surveys | Phylogeography | Participants | Literature cited

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