Sagata K.,PNG Institute of Biological Research |
Mack A.L.,Powdermill Nature Reserve |
Wright D.D.,PNG Institute of Biological Research |
Lester P.J.,Victoria University of Wellington
Insectes Sociaux | Year: 2010
Tropical ant communities are frequently diverse, but highly patchy in nature. The availability of suitable nest sites may be a regulating force in structuring litter ant communities. Our aim was to examine ant resource utilization in naturally occurring twigs, and to modify the availability of these resources in order to quantify the influence of nest availability on ant communities in a Papua New Guinean forest. First, we compared ant communities that assemble in artificial twigs (drilled, wooden dowels), naturally occurring twigs, and the leaf litter. A total of 55 ant species were captured: 33 from the leaf litter, 29 from naturally occurring twigs, and only 12 from artificial nests. Significantly different communities formed in each of the three nest types. Second, we examined how the density of natural or artificial nest material influenced the ant abundance and species richness. Plots had between 5 and 96 potential nest sites. An average of only 11.2% of these twigs was colonized. Both species richness and the total abundance of adult ants were significantly positively correlated with increasing naturally occurring twig density. Conversely, increasing the availability of artificial nests from 5 to 20 per plot had no significant effect on the proportion of artificial nests colonized, species richness, or the colony size. We observed that ant species richness and abundance increased with natural twig density, at least for naturally occurring communities. But why so many twigs remain vacant and available for ant colonization remains unknown. Other biotic and abiotic factors likely influence the use of nesting habitat in these ant communities. © International Union for the Study of Social Insects (IUSSI) 2010.
Warakai D.,P.O. Box 7013 |
Okena D.S.,PNG Institute of Biological Research |
Igag P.,PNG Institute of Biological Research |
Opiang M.,PNG Institute of Biological Research |
Mack A.L.,Indo Pacific Conservation Alliance
Tropical Conservation Science | Year: 2013
Little is known of the frequency of use and reliance upon tree cavities by wildlife, nor the natural availability of cavities in New Guinea forests. We surveyed the literature for records of cavity use by birds and mammals in New Guinea. We examined every standing tree on one hectare of primary forest and one hectare of secondary forest for cavities, then carefully assessed every tree for cavities after they were felled. We put up 190 artificial nest boxes of five designs in three sites and monitored occupancy. At least 50 species (23.6%) of New Guinea terrestrial mammals and 118 species (17.7%) of non-marine or aquatic bird species are recorded in the literature as using tree cavities. Ground observation identified 36 suspected cavities in a hectare of lowland primary forest and 10 in nearby secondary forest. Upon inspection of all trees after felling, these figures changed to 26 and 0 respectively. Ground censuses are not accurate. Cavities were more commonly found in large trees. In less than a year, nest box occupancy reached exceeded 33%, with Phalanger spp. and Sugar gliders, Petaurus breviceps, being most common. Some bird use was detected by the presence of feathers; snakes and geckos were also found in boxes. Occupancy increased with time and would probably be higher after a second year. The larger boxes had greater occupancy, as did boxes placed higher in the trees. Bees occupied and probably excluded other users from 10% of boxes. As Papuan forests are disturbed by logging, hunting practices and gardening, conservationists might need to manage practices to ensure cavity availability. Artificial nest boxes might have utility for wildlife conservation and research. © Diatpain Warakai, Daniel Solomon Okena, Paul Igag, Muse Opiang and Andrew L. Mack.