Male tawny dragons use throat patterns to recognize rivals

The ability to distinguish between familiar and unfamiliar conspecifics is important for many animals, especially territorial species since it allows them to avoid unnecessary interactions with individuals that pose little threat. There are very few studies, however, that identify the proximate cues that facilitate such recognition in visual systems. Here, we show that in tawny dragons (Ctenophorus decresii), males can recognize familiar and unfamiliar conspecific males based on morphological features alone, without the aid of chemical or behavioural cues. We further show that it is the colour pattern of the throat patches (gular) that facilitates this recognition.     

The effects of quality improvement practices on team effectiveness: a mediational model

Researchers have been challenged to specify the processes that quality improvement (QI) practices could be expected to generate and to explain how they might contribute to organizational effectiveness. This research article meets that challenge through a study of 97 teams in the health care field. The authors developed a ‘Quality Improvement Practices Index’ and showed that QI practices could be differentiated from traditional team‐level variables, and that such practices affect both directly and indirectly (through team‐level variables) team effectiveness. Two models were tested using structural equation modelling. It was found that the perceptions of the impact of QI practices on team effectiveness varied depending on who was assessing the team's performance—members of the team or managers who were external to the team but responsible for the team's performance. The authors discuss the implications of these results both for researchers and practitioners. Copyright © 2002 John Wiley & Sons, Ltd.     

Building safety in humanitarian programmes that support post-disaster shelter self-recovery: an evidence review

The humanitarian sector is increasingly aware of the role that good quality evidence plays in the underpinning of effective and accountable practice. This review addresses the need for reliable evidence by evaluating current knowledge about the intersection of two key outcome targets of post-disaster shelter response: supporting shelter self-recovery and building back safer. Evidence about post-disaster shelter programmes that aim to improve hazard resistance while supporting shelter self-recovery has been systematically analysed and evaluated. Technical support, especially training in safer construction techniques, was found to be a central programme feature, but the impact of this and other programme attributes on building safety was largely not ascertainable. Programme reports and studies lack sufficient detail, especially on the hazard resistance of repaired houses. Accounts of shelter programmes need to include more reliable reporting of key activities and assessment of outcomes, in order to contribute to the growing evidence base in this field.     

Intraspecific competition affects population size and resource allocation in an ant dispersing by colony fission

Intraspecific competition is a pervasive phenomenon with important ecological and evolutionary consequences, yet its effect in natural populations remains controversial. Although numerous studies suggest that in many cases populations across all organisms are limited by density-dependent processes, this conclusion often relies on correlative data. Here, using an experimental approach, we examined the effect of intraspecific competition on population regulation of the ant Aphaenogaster senilis. In this species females are philopatric while males disperse by flying over relatively long distances. All colonies were removed from 15 experimental plots, except for one focal colony in each plot, while 15 other plots remained unmanipulated. After the first reproductive season, nest density in the experimental plots returned to a level nonsignificantly different from that in the control plots, which was not expected if the populations were indeed regulated by density-independent phenomena. In both the control plots and the experimental plots colonies remained overdispersed throughout the experiment, suggesting colony mutual exclusion. Nests outside the plots rapidly extended their foraging span, but we did not detect any significant inward migration into the experimental plots. Experimental reduction in density did not significantly affect the focal colonies' biomass, measured just before the first reproductive season. However, the ratio of males to workers-pupae biomasses was smaller in experimental plots, suggesting that colonies there had redirected part of the resources normally allocated to male production to the production instead of new workers. Microsatellite analysis indicated that, after the reproductive season, many colonies in the experimental plots were headed by a young queen that was the mother of the brood but not of the old workers, indicating that reduction in colony density stimulated fission of the remaining colonies. Finally, at the end of the experiment, 14 months after experimental reduction in density, colonies that derived from fission were smaller in the experimental than in the control plots, suggesting that the former had undergone fission at a smaller size than in control plots, which presumably allowed them to colonize the emptied areas. We conclude that colonies adjust resource allocation and colony fission to the degree of intraspecific competition.     

Fatty acid profiles of juvenile salmon indicate prey selection strategies in coastal marine waters

Juvenile salmon exhibit high growth rates upon their arrival into the marine environment. Dietary changes from freshwater and estuarine habitats to those derived from the marine environment may play an important role in ultimate adult survival. We measured the total lipid and fatty acid (FA) composition of juvenile Chinook salmon (Oncorhynchus tshawytscha), coho salmon (O. kisutch), and 18 of their potential prey items sampled from coastal waters during their first few months at sea. Coho salmon had significant reductions in their lipid content (% wet weight) between May and June, likely due to early marine growth. We did not find a significant drop between May and June Chinook salmon lipid content, which may indicate an earlier ontogenetic selection to marine prey that are higher in lipids and essential fatty acids (EFAs). Juvenile salmon ate prey of both high and low lipids. Significant FA compositional changes occurred for both coho and Chinook salmon between May and June. In May, the FA profile of juvenile salmon, especially coho salmon, did not resemble their prey items; however, in June, there was a strong correlation between salmon and their common fish prey as determined by gut content analysis. Significant increases in the level of EFAs, especially docosahexaenoic acid (DHA, 22:6n-3) accounted for the majority of the monthly differences in salmon tissue FA composition. In order for juvenile salmon to adequately meet their physiological requirements, they may have adapted to select advantageous prey with higher levels of EFAs, especially DHA, in order to rapidly increase their growth and ultimate survival.     

Land trust evaluation of progress toward conservation goals

In the United States local land trusts preserve and conserve land to protect water quality and supply, farmlands, habitat for native plants and animals, areas of cultural or historical significance, and scenic views. We surveyed the 24 active, local land trusts in North Carolina (U.S.A.) to determine how they report progress toward attaining such conservation goals. Twenty-two land trusts responded to our survey. Of these, eight reported developing specific conservation goals for all of the properties they protect, five identified conservation targets on all properties, and two reported monitoring biological indicators on all of their protected properties. On the basis of these results, we believe most of the land trusts surveyed could not determine whether they were meeting conservation goals because most did not identify explicit, measurable goals and monitor progress toward them. Instead they reported success in terms of the amount of land protected and money raised. We think this is a lost opportunity for land trusts to build sound approaches to environmental management, engage the public, entice new donors, and attain funding for additional conservation activities. We propose conservation professionals help local land trusts adopt the Open Standards for the Practice of Conservation, a framework developed by a consortium of international conservation organizations, to develop conservation goals and measure whether the goals are achieved.     

Unravelling a ‘miner’s myth’ that environmental contamination in mining towns is naturally occurring

Australia has a long history of metal mining and smelting. Extraction and processing have resulted in elevated levels of toxic metals surrounding mining operations, which have adverse health effects, particularly to children. Resource companies, government agencies and employees often construct ‘myths’ to down play potential exposure risks and responsibility arising from operating emissions. Typical statements include: contaminants are naturally occurring, the wind blows emissions away from residential areas, contaminants are not bioavailable, or the problem is a legacy issue and not related to current operations. Evidence from mining and smelting towns shows that such ‘myths’ are exactly that. In mining towns, the default and primary defence against contamination is that elevated metals in adjacent urban environments are from the erosion and weathering of the ore bodies over millennia—hence ‘naturally occurring’. Not only is this a difficult argument to unravel from an evidence-based perspective, but also it causes confusion and delays remediation work, hindering efforts to reduce harmful exposures to children. An example of this situation is from Broken Hill, New South Wales, home to one of the world’s largest lead–zinc–silver ore body, which has been mined continuously for over 130 years. Environmental metal concentration and lead isotopic data from soil samples collected from across Broken Hill are used to establish the nature and timing of lead contamination. We use multiple lines of evidence to unravel a ‘miner’s myth’ by evaluating current soil metal concentrations and lead isotopic compositions, geological data, historical environmental assessments and old photographic evidence to assess the impacts from early smelting along with mining to the surface soils in the city.