Notes on the high elevation mammal fauna of the Kaijende Highlands, Enga Province, Papua New Guinea

Renewed mammal survey efforts in high elevation forests and subalpine habitats in the Kaijende Highlands, undertaken in July 2008, recorded 17 species of mammals (9 marsupials, 7 rodents, 1 bat) primarily on the basis of small mammal trapping, mistnetting, and examination of bones and teeth recovered from caves. At least two of these species, a bandicoot (Microperoryctes) and a pygmy possum (Cercartetus), are unnamed species, although these do not occur exclusively in the Kaijende Highlands, being known also from other mountain areas of New Guinea. Two species, the insectivorous bat Nyctophilus microdon and the moss mouse Pseudohydromys fuscus, represent new records for Enga Province, and the giant rat Mallomys rothschildi is newly recorded from the Kaijende Highlands. The capture of two individuals of Nyctophilus microdon in forest at 3,315 m extends the recorded elevational distribution of this bat by more than 1,000 m. This survey provided sufficent new information to re-examine the IUCN conservation status classification of two poorly known mammal species (Nyctophilus microdon and Rattus giluwensis, both previously listed as “Data Deficient”, now recommended as species to be classified as “Least Concern”), an important result for conservation prioritization and planning. The presence of the amphibious rat Crossomys moncktoni, previously recorded from the Kaijende Highlands only on the basis of informant interviews, is confirmed by a mandible from a cave deposit, probably accumulated via predation by the Sooty Owl, Tyto tenebricosa. Close inspection of mammal remains from a single cave accumulation revealed that at least 12 species of mammals, mostly nocturnal taxa weighing less than 500 grams, make up the diet of owls in the area, with the Pygmy ringtail Pseudochirulus mayeri being the most important prey species. This survey brings the total number of native mammal species known to occur in the Kaijende Highlands above 2,000 meters to 38, and in Enga Province to at least 41.