Jenis-Jenis Tikus (Rodentia: Muridae) Dan Pakan Alaminya Di Daerah Pertanian Sekitar Hutan Di Kabupaten Banggai, Sulawesi Tengah The Species Of Rats (Rodentia: Muridae) And Their Foods In Agricultural Area In Surounding

Abstract: The species diversity of rats (Rodentia: Muridae) differs on each island in Indonesia. There are at least 16 genera of 41 species of rats in Sulawesi Island. Recently it has been reported that rats attack relatively new paddy field surrounding forest, but the identity of the species is still unknown. The objectives of this research are to assess the rat\u27s diversity and the guilds of rats living around the forest. The research was done in agricultural area surrounding forest in Siuna, foothill of Tompotika Mt, Banggai Regency, Central Sulawesi. Rats in the forest and coconut plantation were captured using Sherman traps, which were randomly situated. Rats in paddy field were captured by trap barrier system (TBS). Habitat condition and the presence of predators were recorded. All rat specimens were identified to their scientific names using Corbert & Hill (1992). Their stomach contents was put in 70% alcohol, taken 5 samples for each stomach, and analyzed under a.microscope to determine their feed. The data were interpreted descriptively, which was emphasizing its potency as a pest. The result shows that there are 7 genera i.e. Bunomys, Maxomys, Taeromys, Paruromys, Tateomys, Mus, Rattus and 18 species of rats. Bunomys sp., B. penitus, B. prolatus, Maxomys sp., M. musschenbroekii, M. dollmani, Taeromys sp., T. callitrichus, T. celebensis, T. rhinogradoide Paruromys ursinus, P. camurus, and P. dominator occupy the forest. B. heinrichi, B. prolatus, M. musschenbroekii, P. camurus, Mus musculusand Rattus nitidus ocupy coconut plantation. R. argentiventer, R. exulans and R. nitidus occupies the paddy field. The stomach content examination shows that B. prolatus, M. musschenbroekii, R. exulans, R. nitidus, and T. rhinogradoides eat mostly animal materials, especially member of Phylum ArthropodaR. argentiventer mostly eat plant material, especially member of Family Graminae (grass family). Unfortunately the stomach contents B. heinrichi, B. pemtus, M. musculus, and T. callitrichus couldn\u27t identified since it was either empty and or severely damaged. The field data and literature study, suggest that R. argentiventer and R. exulans are pests or at least potential pests in the paddy field. B. heinrichi, B. penitus, B. prolatus, M. musschenbroekii, M. musculus, R. nitidus, and T. callitrichus are potential pests, since those species are basically omnivorous. However M. musculus prefers to eat grains. Meanwhile T. rhinogradoides is not potential to be a pest since it is carnivorous. Key words:TBS, omnivorous, predato

Can camera traps monitor Komodo dragons a large ectothermic predator?

Camera trapping has greatly enhanced population monitoring of often cryptic and low abundance apex carnivores. Effectiveness of passive infrared camera trapping, and ultimately population monitoring, relies on temperature mediated differences between the animal and its ambient environment to ensure good camera detection. In ectothermic predators such as large varanid lizards, this criterion is presumed less certain. Here we evaluated the effectiveness of camera trapping to potentially monitor the population status of the Komodo dragon (Varanus komodoensis), an apex predator, using site occupancy approaches. We compared site-specific estimates of site occupancy and detection derived using camera traps and cage traps at 181 trapping locations established across six sites on four islands within Komodo National Park, Eastern Indonesia. Detection and site occupancy at each site were estimated using eight competing models that considered site-specific variation in occupancy (ψ)and varied detection probabilities (p) according to detection method, site and survey number using a single season site occupancy modelling approach. The most parsimonious model [ψ (site), p (site survey); ω = 0.74] suggested that site occupancy estimates differed among sites. Detection probability varied as an interaction between site and survey number. Our results indicate that overall camera traps produced similar estimates of detection and site occupancy to cage traps, irrespective of being paired, or unpaired, with cage traps. Whilst one site showed some evidence detection was affected by trapping method detection was too low to produce an accurate occupancy estimate. Overall, as camera trapping is logistically more feasible it may provide, with further validation, an alternative method for evaluating long-term site occupancy patterns in Komodo dragons, and potentially other large reptiles, aiding conservation of this species

Jenis-Jenis Tikus (Rodentia: Muridae) dan Pakan Alaminya di Daerah Pertanian Sekitar Hutan di Kabupaten Banggai, Sulawesi Tengah

The species diversity of rats (Fam. Muridae) differs on each island in Indonesia. There are at least 16 genera of 41 species of rats in Sulawesi Island. Recently it has been reported that rats attack relatively new paddy field surrounding forest, but the identity of the species is still unknown. The objectives of this research are to assess the rat's diversity and the guilds of rats living around the forest. The research was done in agricultural area surrounding forest in Siuna, foothill of Tompotika Mt, Banggai Regency, Central Sulawesi. Rats in the forest and coconut plantation were captured using Shermann traps, which were randomly situated. Rats in paddy field were captured by trap barrier system (TBS). Habitat condition and the presence of predators were recorded. All rat specimens were identified to their scientific names using Corbert & Hill (1992). Their stomach contents was put in 70% alcohol, taken 5 samples for each stomach, and analyzed under a microscope to determine their feed. The data were interpreted descriptively, which was emphasizing its potency as a pest. The result shows that there are 7 genera i.e. Bunomys, Maxomys, Taeromys, Paruromys, Tateomys, Mus, Rattus and 18 species of rats. Bunomys sp., B. penitus, B. prolatus, Maxomys sp., M. musschenbroekii, M. dollmani, Taeromys sp., T. callitrichus, T. celebensis, T. rhinogradoide, Paruromys ursinus, P. camurus, and P. dominator occupy the forest. B. heinrichi, B. prolatus, M. musschenbroekii, P. camurus, Mus musculus; and Rattus nitidus ocupy coconut plantation. R. argentiventer, R. exulans and R. nitidus occupies the paddy field. The stomach content examination shows that B. prolatus, M. musschenbroekii, R. exulans, R. nitidus, and T. rhinogradoide eat mostly animal materials, especially member of Phylum Arthropoda; R. argentiventer mostly eat plant material, especially member of Family Graminae (grass family). Unfortunately the stomach contents B. heinrichi, B. penitus, M. musculus, and T. callitrichus couldn't identified since it was either empty and or severely damaged. The field data and literature study, suggest that R. argentiventer and R. exulans are pests or at least potential pests in the paddy field. B. heinrichi, B. penitus, B. prolatus, M. musschenbroekii, M. musculus, R. nitidus, and T. callitrichus are potential pests, since those species are basically omnivorous. However M. musculus prefers to eat grains. Meanwhile T. rhinogradoides is not potential to be a pest since it is carnivorous

Distribution, seasonal use, and predation of incubation mounds of Orange-footed Scrubfowl on Komodo Island, Indonesia

Megapodes are unique in using only heat from the environment, rather than body heat, to incubate their eggs as well as the precocious independence of their chicks on hatching. Of 22 recognized species of megapodes, 9 are listed as threatened due to factors including habitat loss and fragmentation, and predation on eggs and chicks. Orange-footed Scrubfowl (Megapodius reinwardt) are conspicuous components of the Oriental/Austral avifauna that inhabit the monsoon forests of the Lesser Sunda chain of islands in Indonesia. We examined the abundance, patterns of distribution, physical characteristics, seasonal activity, and predation risk of incubation mounds of Orange-footed Scrubfowl on Komodo Island in eastern Indonesia. We surveyed 13 valleys on Komodo Island from April 2002 to January 2005 and located 113 tended and 107 untended incubation mounds. Densities of scrubfowl mounds in our study were similar to that reported by investigators during the 1970s, suggesting little change in the scrubfowl population since then. Most scrubfowl mounds were on sandy or loamy soils in open monsoon forest with little overhead shade, and placement of mounds in such areas may ensure adequate temperatures for egg incubation. Although some mounds were tended during all months, mound use peaked during the late wet season in March. During the dry season (April-November), only a few mounds were tended. Komodo dragons (Varanus komodoensis) and wild pigs (Sus scrofa) were the primary predators of scrubfowl eggs, with no indication of egg predation by humans. The valley with the largest number of untended mounds in our study also had the largest number of active Komodo dragon nests. This suggests an effect of Komodo dragons on scrubfowl numbers, but additional study is needed

Evaluation of three field monitoring-density estimation protocols and their relevance to Komodo dragon conservation

Finding practical ways to robustly estimate abundance or density trends in threatened species is a key facet for effective conservation management. Further identifying less expensive monitoring methods that provide adequate data for robust population density estimates can facilitate increased investment into other conservation initiatives needed for species recovery. Here we evaluated and compared inference-and cost-effectiveness criteria for three field monitoring-density estimation protocols to improve conservation activities for the threatened Komodo dragon (Varanus komodoensis). We undertook line-transect counts, cage trapping and camera monitoring surveys for Komodo dragons at 11 sites within protected areas in Eastern Indonesia to collect data to estimate density using distance sampling methods or the Royle-Nichols abundance induced heterogeneity model. Distance sampling estimates were considered poor due to large confidence intervals, a high coefficient of variation and that false absences were obtained in 45 % of sites where other monitoring methods detected lizards present. The Royle-Nichols model using presence/absence data obtained from cage trapping and camera monitoring produced highly correlated density estimates, obtained similar measures of precision and recorded no false absences in data collation. However because costs associated with camera monitoring were considerably less than cage trapping methods, albeit marginally more expensive than distance sampling, better inference from this method is advocated for ongoing population monitoring of Komodo dragons. Further the cost-savings achieved by adopting this field monitoring method could facilitate increased expenditure on alternative management strategies that could help address current declines in two Komodo dragon populations.<br /

Location of study sites and trapping points.

<p>Location of six study sites on three islands within Komodo National Park were used to evaluate detection and site occupancy using cage and camera trapping for Komodo dragons. The lower panel (B) depicts a site-specific trapping design example (from the Liang site on Komodo Island) used to compare Komodo dragon detection probabilities at paired cage and camera traps or camera trap only point locations.</p

Ranking of linear and non-linear regression models relative to the null model examining the relationship between Komodo dragon detections obtained from cage traps and cameras.

<p>Table describes estimated number of parameters (P_D), Deviance Information Criterion (DIC), change in DIC (ΔDIC) relative to the most parsimonious model, and model weight (<i>w</i>).</p

Ecological allometries and niche use dynamics across Komodo dragon ontogeny

Ontogenetic allometries in ecological habits and niche use are key responses by which individuals maximize lifetime fitness. Moreover, such allometries have significant implications for how individuals influence population and community dynamics. Here, we examined how body size variation in Komodo dragons (Varanus komodoensis) influenced ecological allometries in their: (1) prey size preference, (2) daily movement rates, (3) home range area, and (4) subsequent niche use across ontogeny. With increased body mass, Komodo dragons increased prey size with a dramatic switch from small (&le;10 kg) to large prey (&ge;50 kg) in lizards heavier than 20 kg. Rates of foraging movement were described by a non-linear concave down response with lizard increasinghourly movement rates up until &sim;20 kg body mass before decreasing daily movement suggesting reduced foraging effort in larger lizards. In contrast, home range area exhibited a sigmoid response with increased body mass. Intrapopulation ecological niche use and overlap were also strongly structured by body size. Thus, ontogenetic allometries suggest Komodo dragon&rsquo;s transition from a highly active foraging modeexploiting small prey through to a less active sit and wait feeding strategy focused on killing large ungulates. Further, our results suggest that as body size increases across ontogeny, the Komodo dragon exhibited marked ontogenetic niche shifts that enabled it to function as an entire vertebrate predator guild by exploiting prey across multiple trophic levels