Australians through internationally competitive and sustainable business. To this end, the Department has initiatives to assist the growth of key industry sectors. One such initiative is the National Nanotechnology Strategy Taskforce, which was established by the Minister for Industry, Tourism and Resources, Mr Ian Macfarlane, to develop options for a coordinated, national strategy on the emerging area of nanotechnology by 30 June 2006.

https://researchlibrary.agric.wa.gov.au/cgi/viewcontent.cgi?article=1000&context=aq_frcr

Improved performance of marron using genetic and pond management strategies

North America harbors about 390 native species of crayfishes, 75% of the world's total. In this article, we highlight the threats posed by nonindigenous crayfishes to freshwater ecosystem function, fisheries, and the biodiversity of native crayfishes; draw some lessons for North American freshwater conservation from the experience with nonindigenous crayfishes in Europe; and review existing regulations that address the introduction of nonindigenous crayfishes. Most North American crayfishes have naturally small ranges in the southeastern United States, rendering them very vulnerable to environmental change. In contrast, Europe has only five, broadly distributed, native crayfishes, all of which have been greatly affected by environmental changes, especially the introduction of nonindigenous crayfishes (mostly from North America). In response, many European governments have adopted strict regulations to protect native crayfishes. The loss of thousands of populations of native European crayfishes an...

Nonindigenous Crayfishes Threaten North American Freshwater Biodiversity: Lessons from Europe

Efforts to document the decline of extant populations require a historical record of previous occurrences. Natural history museums contain such information for most regions of the world, at least at a coarse spatial scale. Museum collections have been successfully used to analyse declines in a wide range of plants and animals, at spatial scales ranging from single localities to large biotic and political regions. Natural history museum collections, when properly analysed, can be an invaluable tool in documenting changes in biodiversity during the past century.

The role of natural history collections in documenting species declines.

Understanding of animal social and sexual evolution has seen a renaissance in recent years with discoveries of frequent infidelity in apparently monogamous species, the importance of sperm competition, active female mate choice, and eusocial behavior in animals outside the traditional social insect groups Each of these findings has raised new questions, and suggested new answers, about the evolution of behavioral interactions among animals This volume synthesizes recent research on the sexual and social biology of the Crustacea, one of the dominant invertebrate groups on earth Its staggering diversity includes ecologically important inhabitants of nearly every environment from deep-sea trenches, through headwater streams, to desert soils The wide range of crustacean phenotypes and environments is accompanied by a comparable diversity of behavioral and social systems, including the elaborate courtship and wildly exaggerated morphologies of fiddler crabs, the mysterious queuing behavior of migrating spiny lobsters, and even eusociality in coral-reef shrimps This diversity makes crustaceans particularly valuable for exploring the comparative evolution of sexual and social systems Despite exciting recent advances, however, general recognition of the value of Crustacea as models has lagged behind that of the better studied insects and vertebrates This book synthesizes the state of the field in crustacean behavior and sociobiology and places it in a conceptually based, comparative framework that will be valuable to active researchers and students in animal behavior, ecology, and evolutionary biology It brings together a group of internationally recognized and rising experts in fields related to crustacean behavioral ecology, ranging from physiology and functional morphology, through mating and social behavior, to ecology and phylogeny Each chapter makes connections to other, non-crustacean taxa, and the volume closes with a summary section that synthesizes the contributions, discusses anthropogenic impacts, highlights unanswered questions, and provides a vision for profitable future research

Evolutionary ecology of social and sexual systems : crustaceans as model organisms

Aggressiveness, along with foraging voracity and boldness, are key behavioral mechanisms underlying the competitive displacement and invasion success of exotic species However, do aggressiveness, voracity and boldness of the invader depend on the presence of an ecologically similar native competitor in the invaded community? We conducted four behavioral assays to compare aggression, foraging voracity, threat response and boldness to forage under predation risk of multiple populations of exotic signal crayfish Pacifastacus leniusculus across its native and invaded range with and without a native congener, the Shasta crayfish P fortis We predicted that signal crayfish from the invaded range and sympatric with a native congener (IRS) should be more aggressive to outcompete a close competitor than populations from the native range (NR) or invaded range and allopatric to a native congener (IRA) Furthermore, we predicted that IRS populations of signal crayfish should be more voracious, but less bold to forage under predation risk since native predators and prey likely possess appropriate behavioral responses to the invader Contrary to our predictions, results indicated that IRA signal crayfish were more aggressive towards conspecifics and more voracious and active foragers, yet also bolder to forage under predation risk in comparison to NR and IRS populations, which did not differ in behavior Higher aggression/voracity/boldness was positively correlated with prey consumption rates, and hence potential impacts on prey We suggest that the positive correlations between aggression/voracity/boldness are the result of an overall aggression syndrome Results of stream surveys indicated that IRA streams have significantly lower prey biomass than in IRS streams, which may drive invading signal crayfish to be more aggressive/voracious/bold to acquire resources to establish a population

Differences in aggression, activity and boldness between native and introduced populations of an invasive crayfish.

Native freshwater faunas in North America are declining, principally due to the combined effects of habitat degradation and introduced species. Relatively little attention has been directed to the decline of freshwater invertebrates, which may be even more threatened than fishes. This paper chronicles recent changes in the distribution and abundance of the Shasta crayfish (Pacifastacus fortis Faxon), a state and federally endangered species endemic to the midreaches of the Pit River system in northeastern California. We made snorkeling and SCUBA surveys for crayfish in 1990 and 1991 and examined various records for historic distributions. Shasta crayfish have been extirpated from much of their historic range by water impoundment and diversion, and they are further threatened by two introduced crayfish species (Pacifastacus leniusculus Dana and Orconectes virilis Hagen). By 1990 Shasta crayfish were restricted to seven isolated populations, mostly in the headwaters of spring-fed tributaries to the Pit river. P. leniusculus had become established throughout much of the study area in about 12 years. In one site P. leniusculus probably contributed to the precipitous decline of Shasta crayfish, from 2000–3000 in 1980 to about 370 (± 135) in 1991. O. virilis, which occurred in only the most disturbed parts of the system, showed little range expansion in 30 years and had been replaced in a large stretch of the Pit River by P. leniusculus. P. leniusculus occupied sites with a broad range of habitat variables (temperature, pH, turbidity, substrate size) partly or wholly overlapping measures of sites with the other two species. The decline of the Shasta crayfish, like the extinction of its closest relative P. nigrescens in the San Francisco Bay area earlier this century, reflects the decline of its habitat and probably pressure from the aggressive exotic P. leniusculus.

Decline of the Shasta Crayfish (Pacifastacus fortis Faxon) of Northeastern California

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Decline of the Shasta Crayfish (Pacifastacus fortis Faxon) of Northeastern California