A structured analysis of risk to important wildlife elements in three Australian Wildlife Conservancy sanctuaries

Where data and information are lacking, structured expert risk assessments can provide a powerful tool to progress natural resource planning. In many situations, practitioners make informal assessments of risk within small groups that typically constitute employees. In this study, we report on three small (in terms of experts) structured expert‐based risk assessment case studies conducted by expert employees of a not‐for‐profit organisation (Australian Wildlife Conservancy) to demonstrate the utility of the approach. The case studies were carried out for three wildlife sanctuaries managed by AWC: Faure Island, Karakamia and Paruna. The likelihood that a set of direct risk factors would cause management failure for sets of important wildlife elements in the three sanctuaries was elicited from the small group of ecological experts. The analysis was couched in terms of a management aim to not lose species from each wildlife element over the management period of 25 years with current management. The experts believed, in particular, that increasing temperature and decreasing water availability associated with climate change were likely to impact significantly upon the vegetation elements and water‐reliant fauna associated with the sanctuaries. Some vegetation elements were also thought likely to be at risk of over‐grazing, unsuitable fire regimes and, in some cases, disease. In addition to predation by exotic predators at one sanctuary, the experts identified additional direct risk factors for various fauna elements associated with expected changes to the vegetation elements, including reduction in food availability, nesting habitat, and generally important life media. From the risk analyses, a preliminary conceptual model was developed to underpin monitoring and to indicate areas for possible management intervention and research. The case studies demonstrate that even in a small workplace team, structured risk assessments can be efficiently accomplished and can provide expedient and transparent information that effectively captures and aggregates the views of the experts.     

New insights into the biosynthesis of mycobacterial lipomannan arising from deletion of a conserved gene

Genetic construction of a mutant strain (designated MSMEG4245) of Mycobacterium smegmatis, defective in a broadly conserved gene for a putative glycosyltransferase of the glycosyltransferase-C superfamily, results in a phenotype marked by the virtual absence of the phosphatidylinositol-containing lipomannan and lipoarabinomannan, replaced instead by a novel truncated form of lipomannan. The normal spectrum of phosphatidylinositol mannosides, long presumed precursors of these lipoglycans, was retained. Matrix-assisted laser desorption/ionization-time of flight/mass spectrometry of the mutated form of lipomannan shows a family of phosphatidylinositol-anchored lipomannans with from only 5 to 20 Manp residues as compared with lipomannan from the wild type strain consisting of 21-34 Manp residues but with few changes in the branching pattern. Thus, MSMEG4245 is apparently a key mannosyltransferase, required for the proper elongation of lipomannan to its normal state and subsequent synthesis of lipoarabinomannan. The corresponding ortholog in Mycobacterium tuberculosis H37Rv has been identified as Rv2174. This previously unrecognized feature of the biosynthesis of lipomannan/lipoarabinomannan allows a significant revision of structural and biosynthetic schemata and provides a molecular basis of selectivity in biosynthesis, as conferred by the MSMEG4245 gene.     

Microbial control of black cutworm (Lepidoptera: Noctuidae) in turfgrass using Agrotis ipsilon multiple nucleopolyhedrovirus

Agrotis ipsilon multiple nucleopolyhedrovirus (family Baculoviridae, genus Nucleopolyhedrovirus, AgipMNPV), a naturally occurring baculovirus, was found infecting black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae), on central Kentucky golf courses. Laboratory, greenhouse, and field studies investigated the potential of AgipMNPV for managing black cutworms in turfgrass. The virus was highly active against first instars (LC50 = 73 occlusion bodies [OBs] per microl with 2-microl dose; 95% confidence intervals, 55-98). First instars that ingested a high lethal dose stopped feeding and died in 3-6 d as early second instars, whereas lethally infected fourth instars continued to feed and grow for 4-9 d until death. Sublethal doses consumed by third or fifth instars had little or no effect on subsequent developmental rate or pupal weight. Horizontal transmission of AgipMNPV in turfgrass plots was shown. Sprayed suspensions of AgipMNPV (5 x 10(8) - 6 x 10(9) OBs/m2) resulted in 75 to > 93% lethal infection of third or fourth instars in field plots of fairway-height creeping bentgrass, Agrostis stolonifera (Huds.), and on a golf course putting green collar. Virus spray residues (7 x 10(9) OBs/m2) allowed to weather on mowed and irrigated creeping bentgrass field plots significantly increased lethal infection of implanted larvae for at least 4 wk. This study, the first to evaluate a virus against a pest in turfgrass, suggests that AgipMNPV has potential as a preventive bioinsecticide targeting early instar black cutworms. Establishing a virus reservoir in the thatch and soil could suppress successive generations of that key pest on golf courses and sport fields.     

Importance of Long-Term Cycles for Predicting Water Level Dynamics in Natural Lakes

Lakes are disproportionately important ecosystems for humanity, containing 77% of the liquid surface freshwater on Earth and comprising key contributors to global biodiversity. With an ever-growing human demand for water and increasing climate uncertainty, there is pressing need for improved understanding of the underlying patterns of natural variability of water resources and consideration of their implications for water resource management and conservation. Here we use Bayesian harmonic regression models to characterise water level dynamics and study the influence of cyclic components in confounding estimation of long-term directional trends in water levels in natural Irish lakes. We found that the lakes were characterised by a common and well-defined annual seasonality and several inter-annual and inter-decadal cycles with strong transient behaviour over time. Importantly, failing to account for the longer-term cyclic components produced a significant overall underestimation of the trend effect. Our findings demonstrate the importance of contextualising lake water resource management to the specific physical setting of lakes.     

An Artificial “gum-tree” for marmosets (Callithrix j. jacchus)

Marmosets (Callithrix, Cebuella) in the wild gouge wells in trees and eat the exudates that accumulate there. An artificial gum-tree was made of wooden dowel and filled with Acacia Senegal exudate (gum arabic) dissolved in water. Three families of marmosets avidly gouged and consumed gum from this device, showing all of the behavioral patterns described in nature. The gum-tree cost little and was easy to make.     

Substantial genetic divergence between morphologically indistinguishable populations of Fasciola suggests the possibility of cryptic speciation

The liver flukes, Fasciola hepatica and Fasciola gigantica, are considered to be sister species and between them present a major threat worldwide to livestock production. In this study sequence data have been employed from informative regions of the nuclear and mitochondrial genomes of over 200 morphologically F. hepatica-like or F. gigantica-like flukes from Europe, sub-Saharan Africa and South Asia to assess genetic diversity. Evidence is presented for the existence of four well-separated clades: African gigantica-like flukes, Indian gigantica-like flukes, European hepatica-like flukes and African high-altitude hepatica-like flukes. Application of the Biological Species Concept to trematodes is problematic; however, the degree of separation between these groups was sufficient for them to be considered as distinct species using the four times rule for speciation.     

Structural requirements for notch signalling with delta and serrate during the development and patterning of the wing disc of Drosophila

The delta and Serrate proteins interact with the extracellular domain of the Notch receptor and initiate signalling through the receptor. The two ligands are very similar in structure and have been shown to be interchangeable experimentally; however, loss of function analysis indicates that they have different functions during development and analysis of their signalling during wing development indicates that the Fringe protein can discriminate between the two ligands. This raises the possibility that the signalling of delta and Serrate through Notch requires different domains of the Notch protein. Here we have tested this possibility by examining the ability of delta and Serrate to interact and signal with Notch molecules in which different domains had been deleted. This analysis has shown that EGF-like repeats 11 and 12, the RAM-23 and cdc10/ankyrin repeats and the region C-terminal to the cdc10/ankyrin repeats of Notch are necessary for both delta and Serrate to signal via Notch. They also indicate, however, that delta and Serrate utilise EGF-like repeats 24-26 of Notch for signalling, but there are significant differences in the way they utilise these repeats.