Incorporating Habitat Mapping into Practical Koala Conservation on Private Lands

Abstract: Identifying and conserving faunal habitat on private lands has been conducted largely on a site-by-site basis as development proposals arise. We sought to map koala habitat at a scale suitable for use by a local planning authority so that habitat remnants could be protected and managed while remaining in private ownership. At this scale, the level of detail and accuracy needed by local planners required a new approach to mapping koala habitat. Two independent techniques, community and field surveys, were employed. We mailed a survey to every household in Coffs Harbour shire. Respondents told of 3309 koala sightings. We conducted a field survey, a plot-based scat (  fecal pellet) search, to determine which vegetation types and tree species were preferred by koalas. We surveyed 119 sites, which contained 42 different vegetation types. Of these, 37 (31%) had been used by koalas. The outcomes of the community and field surveys were combined to produce a distribution map of koala habitat. The most striking outcome has been the use of our results by the local government authority, Coffs Harbour City Council: planners have incorporated the koala habitat map into their local environmental plan. Our procedure offers a rigorous, repeatable, and publicly accessible method for identifying and mapping important habitat for the purposes of land-use planning, an essential procedure for conserving habitat outside the reserve system.     

Influence of an insect growth regulator on the larval development of an estuarine shrimp

The influence of methoprene, an insect growth regulator used in mosquito control, on larval development of the estuarine grass shrimp (Palaemonetes pugio) was examined in the laboratory. No grass shrimp larvae successfully completed metamorphosis when continuously exposed to 1000 microg methoprene litre(-1). Completion of larval metamorphosis was significantly reduced by exposure to 100 microg litre(-1) of the isomeric mixture (R,S)-methoprene but not the single isomer formulation (S)-methoprene. No statistically significant difference was revealed, however, in ability to inhibit metamorphosis between these two isomeric types across the broad range of exposure concentrations from 0.1 to 1000.0 microg litre(-1). The first two larval stages and the final premetamorphic larval stage were more sensitive to methoprene toxicity than intermediate larval stages. Methoprene exposure did not alter either the duration of total larval development or the total number of larval stages prior to metamorphosis.     

Potential effects of climate change on birds of the Northeast

We used three approaches to assess potential effects of climate change on birds of the Northeast. First, we created distribution and abundance models for common bird species using climate, elevation, and tree species variables and modeled how bird distributions might change as habitats shift. Second, we assessed potential effects on high-elevation birds, especially Bicknell’s thrush (Catharus bicknelli), that may be particularly vulnerable to climate change, by using statistical associations between climate, spruce-fir forest vegetation and bird survey data. Last, we complemented these projections with an assessment of how habitat quality of a migratory songbird, the black-throated blue warbler (Dendroica caerulescens) might be affected by climate change. Large changes in bird communities of the Northeast are likely to result from climate change, and these changes will be most dramatic under a scenario of continued high emissions. Indeed, high-elevation bird species may currently be at the threshold of critical change with as little as 1°C warming reducing suitable habitat by more than half. Species at mid elevations are likely to experience declines in habitat quality that could affect demography. Although not all species will be affected adversely, some of the Northeast’s iconic species, such as common loon and black-capped chickadee, and some of its most abundant species, including several neotropical migrants, are projected to decline significantly in abundance under all climate change scenarios. No clear mitigation strategies are apparent, as shifts in species’ abundances and ranges will occur across all habitat types and for species with widely differing ecologies.     

Modeling potential climate change impacts on the trees of the northeastern United States

We evaluated 134 tree species from the eastern United States for potential response to several scenarios of climate change, and summarized those responses for nine northeastern United States. We modeled and mapped each species individually and show current and potential future distributions for two emission scenarios (A1fi [higher emission] and B1 [lower emission]) and three climate models: the Parallel Climate, the Hadley CM3, and the Geophysical Fluid Dynamics Laboratory model. Climate change could have large impacts on suitable habitat for tree species in this region, especially under a high emissions trajectory. Results indicate that while species with potentially increasing areas of suitable habitat in the Northeastern US substantially outnumber those with decreasing areas of habitat, there are key species that show diminishing habitat area: balsam fir (Abies balsamea), paper birch (Betula papyrifera), red spruce (Picea rubens), bigtooth and quaking aspen (Populus grandidentata and P. tremuloides), and black cherry (Prunus serotina). From these results we identified the top 10 losers and gainers for each US state in the region by scenario and emissions trajectory. By combining individual species importance maps and developing assembly rules for various classes, we created maps of potential forest types for the Northeast showing a general loss of the spruce–fir zone with advancing oak–hickory type. Further data, maps, and analysis can be found at http://www.nrs.fs.fed.us/atlas.     

Sexual behavior among parasitic Megarhyssa wasps (Hymenoptera: Ichneumonidae)

Summary Male wasps of three sympatric species of Nearctic Megarhyssa (Hymenoptera: Ichneumonidae) typically form mixed-species (61.7%) aggregations composed of up to 28 males over sites of female emergence. Observations of 107 aggregations over two seasons in New York state revealed two male mating strategies: postemergence copulation on the tree surface and preemergence insemination accomplished by male abdominal insertion into the female emergence hole. Insertions by one or more males (as many as ten consecutively but not more than two simultaneously) occurred at 88% of the aggregations, with each inserting for an average of 24.8 min. Insemination as a result of preemergence insertion had a success rate of 83% while postemergence copulation attempts were successful 30% of the time (average duration 61.9 s). Individual male reproductive success was very low and not correlated with size, arrival order at emergence sites, or tenacity at the site. Males frequently aggregated at sites of male emergences as well as those of nonconspecifics, though conspecifics to the emerger ultimately played the major role at aggregations. Male-male aggression in aggregations was not apparent, though jostling occurred during the insertion period and during postemergence copulation attempts.     

The impact of climate change on the soil/moisture regime of Scottish mineral soils

The likely impact of climate change on the moisture regime of Scottish soils and consequently on agriculture and land use has been addressed using a novel Geographic Information Systems (GIS) approach. Current estimates of changes in summer precipitation by the year 2030 are 0% with an associated uncertainty of +/- 11%. This study considers the worst case scenario of a decrease in rainfall by 11% which will lead to some low rainfall areas experiencing an increased drought risk, particularly on lighter soils. Wet areas with heavy soils could benefit from an increase in the accessibility period for machinery. As the major agricultural land in Scotland is located on the relatively dry east coast where localised problems due to drought are not uncommon even under the present climate, the detrimental effects of a decrease in rainfall for the whole of Scotland are therefore likely to outweigh the benefits. Approximately 8% of Scotland has been identified in this study as soil/climate combinations which will be susceptible to drought should summer rainfall decrease by 11% and summer temperature increase by 1.4 degrees C.     

Emission trading in agriculture: a study of design options using an agent-based approach

The Scottish Government has proposed reducing Scotland’s greenhouse gas (GHG) emissions by at least 80% by 2050, compared to the 1990 baseline level. It is not yet clear how these reductions will be achieved, but it is likely that all sectors will be expected to make some contribution. Depending on their farm activities, farmers have different sets of abatement alternatives—the challenge facing them, however, is in finding strategies that help to meet reduction targets while maintaining their income. In this paper, we use an agent-based modelling approach to study the implications of carbon trading design options aimed at reducing GHG emissions in the agricultural sector, such as auctions, fixed carbon prices, or carbon credit banking. The feasibility of carbon trading scheme options is assessed regarding their ability to ensure that farmers obtain carbon credits at an affordable and adequate price, since low prices would reward farmers not adopting on-farm abatement options and high prices would encourage non-compliance to targets, thus increasing enforcement costs. Assuming a closed market within the agricultural sector, this study shows that farmers may face up to 50% loss of income to achieve a 30% reduction target if this requires a cut in production. However, market design options such as credits banking may allow farmers to progressively adapt to the scheme constraints. At an individual level, the rate of on-farm compliance and the mandated emission reduction target will determine which farmer strategy is the most efficient to cope with a trading scheme.     

Mud,muddle and models in the knowledge value-chain to action on tropical peatland conservation

Tropical peatlands are known not only for their high, area-based, carbon emissions in response to land-use change but also as hot spots of debate about associated data uncertainties. Perspectives are still evolving on factors underlying the variability and uncertainty. Debate includes the ways of reducing emissions through rewetting, reforestation and agroforestry. A knowledge value-chain that is long and complex links (a) fundamental understanding of peat and peatland processes leading to sciencebased quantification and default values, (b) willingness and (c) ability to act towards emission reduction, and ultimately (d) to local, national and global actions that effectively provide rules, incentives and motivation to conserve peat and reduce emissions. We discuss this value chain, its stakeholders and issues that still remain partially unresolved. We conclude that, to shorten the denial and conspiracy-theory stages of debate that otherwise slow down steps B and C, networks of international and national scientists have to be involved at the early stage of identifying policysensitive environmental issues. Models span part of the knowledge value-chain but transition of analysis units requires specific attention, from soil volumes through area and commodity flows to opportunities for reductions. While drainage of peatlands triggers landscape-scale increases in emissions, factors beyond drainage depth, including nutrient supply, may have a major influence on decomposition rates. Attempts to disentangle the contributions of plant and peat-based respiration in surface flux measurements involve assumptions that cannot be easily verified in comparisons between land uses. With progress on A leading to new internationally accepted defaults and with resistance on step B reduced, the reality of C and lack of working solutions for D is currently constraining further progress.