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Dingoes (Canis dingo) are known for hunting and killing animals to meet their energetic requirements, but like almost all predators they also scavenge animal remains. To improve our understanding of dingo scavenging ecology, we investigated the role of abiotic and biotic factors in shaping carcass utilisation by dingoes and further determined whether dingo scavenging influenced carcass persistence in the landscape. To do so, we monitored visitation and scavenging by dingoes using remote cameras positioned on 119 kangaroo carcasses in open and closed canopy habitats and in warm and cool seasons. The carcasses were monitored across multiple study sites, which incorporated forest, alpine and desert ecoregions in Australia. We found that season played an important role in shaping carcass utilisation by dingoes, as well as carcass persistence. Warmer seasons increased the rate of carcass discovery 6.3-fold in the Forest study site and 4.8-fold in the Alpine study site, and also increased the time dingoes spent feeding on carcasses in the Alpine study site. Further, across all study sites, carcasses persisted at least 4.7 times longer in cool compared with warm seasons. On the other hand, carcass utilisation by dingoes was not influenced by habitat, although carcasses were more likely to persist in open compared with closed canopy habitats in the Alpine study site. Finally, our study showed that dingo scavenging may contribute to substantial carcass removal in certain contexts. Indeed, decreased carcass persistence in the Forest study site was evident in the cool season, when dingo scavenging occurred during the first two weeks of monitoring. The variability in results highlights the complexity of patterns in dingo scavenging and, more broadly, of vertebrate scavenging. It emphasises the need to consider multiple abiotic and biotic factors to properly understand the functional roles of different scavenger species. Longer-term studies with additional seasonal replicates may also yield a more detailed picture of the role of dingoes as apex scavengers. [ABSTRACT FROM AUTHOR]

The tree growth and mortality trade-off is well documented and plays a key role in forests by forming the basis of many ecosystem processes and contributing to tree species coexistence. One area that requires further understanding is how the growth-mortality trade-off is influenced by biotic and abiotic interactions in the forest. In this study, we used a 5-year interval of tree growth and mortality demographic data from a 9-ha forest dynamics plot in a temperate old-growth Chinese forest to address two questions, (1) What is the nature of the growth-mortality trade-off among species in this forest? (2) Are there differences between the responses of tree growth and mortality to local neighborhood variables, both biotic and abiotic? Specifically, do these responses vary among species and with tree size? For the first question, we hypothesized that, within species, mortality rate would be negatively correlated with growth rate, whereas among species it would be positively correlated. For the second question, we expected biotic and abiotic factors to both be important for tree mortality; but expected biotic factors to be more important than abiotic factors for tree growth. The responses of tree growth and mortality to local neighborhood variables, both biotic and abiotic, varied among species. Abiotic factors were more important than biotic factors for small trees; biotic variables were stable with tree size for both small and large trees. Our results showed that there were differences between the responses of tree growth and mortality to local neighborhood variables (i.e., biotic and abiotic) in this temperate forest community. The responses of tree mortality to local neighborhood variables strongly varied across species. Abiotic factors were only important for the growth of small trees. Biotic factors were stable with tree size for growth of small and large trees, but not for mortality. Mortality was negatively correlated with growth for large trees within species; growth-mortality trade-off among species was found to be more accentuated for small trees. The responses of tree mortality to local neighborhood variables differed strongly across species, whereas the responses of tree growth to local neighborhood variables varied among size classes. Tree growth and mortality is tightly correlated both within (negatively) and among species (positively), and their relationships are both size dependent in this temperate forest. Our findings highlight that differential responses of tree growth and mortality to local neighborhood variables continue to shape the forest community well after sapling establishment in this temperate forest community. [ABSTRACT FROM AUTHOR]

The article presents a study concerning the distribution of rotifers in the aquaculture station of El Hamma in Gabes, Tunisia from February 2005 to January 2006. The authors mention that the station is comprised of eight interrelated basins with geothermal waters which are used for the fish tilapia production. They also state that the study found 13 rotifers with the Brachionus urceolaris as the most prominent. Furthermore, they stress that the result of the study implicates that the basins were overall oligo-eutrophic.