Tim R. New

The search for common anthropogenic impacts on biodiversity: a global network

We introduce an initiative to assess and compare landscape changes related to human activities on a global scale, using a single group of invertebrates. The GLOBENET programme uses common field methodology (pitfall trapping), to appraise assemblages of ground beetles (Coleoptera, Carabidae) in visually-similar land-mosaics (urban-rural gradients). Carabids were selected as the focal taxon as they are sufficiently varied (both taxonomically and ecologically), abundant and sensitive to the environment. However, work on other taxa is comparable with the GLOBENET framework. The continuum of decreasing human pressure from city centres into the surrounding countryside was selected to represent human-caused disturbance for this initial stage of GLOBENET because these gradients can be found virtually all over the world. Through the broad-scale assessment envisioned in the GLOBENET programme, we seek to separate general, repeated effects on biodiversity from those that depend on local environments or particular biotic assemblages. Based on this understanding we aim to develop simple tools and protocols for assessing ecological effects of human-caused landscape changes, which could help to sustainably manage landscapes for biodiversity and for human requirements. For instance, the response of different functional groups of carabids to these landscape changes may help guide management practices. Further GLOBENET developments and information are available at our website: http://www.helsinki.fi/science/globenet/

Effects of Pitfall Trap Spacing on the Abundance, Richness and Composition of Invertebrate Catches

Pitfall trapping is one of the most commonly used methods to survey surface-active invertebrates, but has many potential biases that may affect the catch of invertebrates. The distance between pitfall traps (inter-trap spacing) is one such factor. The abundance, richness and composition of invertebrate orders, and species of ants and beetles was examined for three commonly used inter-trap spacings (1, 5, 10 m) in a grassy-woodland ecosystem in Victoria, Australia. Abundance and composition was not significantly different between treatments for any taxa. A significant difference in richness between treatments was found only for beetles. The 5 and 10 m treatments had a significantly higher number of beetle morphospecies than the 1 m treatment. Knowledge of such biases, and how subtle variations in trap design affect efficiency, is important for designing invertebrate surveys.

Untangling the Web: Spiders and the Challenges of Invertebrate Conservation

Selection of informative focal groups is an important avenue to increasing the applications of invertebrates in conservation assessments and inventory studies, and to help overcome the challenges of high diversity, all-taxon surveys and taxonomic inadequacy. Spiders are a possible focal group of wide relevance in terrestrial ecosystems, but considerable further work is needed to clarify their broad values as indicators, the relevance of higher taxon surrogacy, the taxonomy of selected families and genera, and to develop standard sampling protocols. The current values of spiders in conservation asessment, and the prospects of enhancing their value as a focal group are enumerated and discussed.

Moths (Insecta: Lepidoptera) and conservation: background and perspective

Most attention to conservation of moths has been to species or assemblages of the ‘macrolepidoptera’, which includes families rivalling the butterflies in their popularity. The more numerous smaller moths have been largely ignored. As for butterflies, the greatest amount of appraisal and information on conservation is from the northern temperate regions, where conservation is accepted readily and promoted widely. Equivalent needs occur elsewhere, but most have not been assessed except in general terms of concern for natural habitats. This introduction outlines the current approaches and background to moth conservation and the use of moths as tools in conservation assessment, and summarises some concerns, contexts and biological background to help appreciate the plight and uses of this predominant constituent of the Lepidoptera in many parts of the world.

How useful are ant assemblages for monitoring habitat disturbance on grasslands in south eastern Australia

Native grasslands are one of the most endangered ecosystems in south eastern Australia. Conservation of grassland remnants and development of effective indicator groups to monitor their quality is a high priority. Recent surveys of epigaeic invertebrates have revealed several candidate groups for this. Ants are a popular focal group for invertebrate surveys in the region. The ant species richness and functional groups on four series of grassland sites in Victoria suggest that small scale heterogeneity is sufficiently high that the predictive indicator values of ants are limited, and that ants may not be sufficiently sensitive to floristic change to employ them alone in monitoring grassland condition in the region.

Conservation Concerns for Butterflies in Urban Areas of Australia

The threats of rapid urbanisation to Australian butterflies are discussed, and examples given of the taxa of conservation concern and measures for their management. Compounding threats, such as intensive recreational activity in coastal regions, are also important consequences of urbanisation. Maintenance of threatened specialist species and more generalist widespread species may demand rather different approaches for practical conservation. Most species capable of persisting in urban areas depend on their adults adapting to modified habitats, and their immature stages utilising cultivated exotic or native food plants. Exotic weeds and inappropriate fire regimes are recognised as major threats to the survival of species in remnant bushland.

Pitfall Trapping for Ants (Hymenoptera, Formicidae) in Mesic Australia: What is the Best Trapping Period?

Increasing trapping periods from 48 h through 5 days and 7 days to 14 days increased species richness of ants captured. However, a high proportion of genera (15/20) and morphospecies (22/33) were taken in the initial 48 h period, and 7 day periods yielded all species later accumulated by 14 days trap use. The shorter periods provide samples that may be adequate for appraising representativeness or typicalness of local ant assemblages, as the data most commonly needed for site evaluation or comparisons, but more extensive sampling is necessary to accumulate all rarer species, including those that may have individual conservation significance.

Insect conservation on islands: setting the scene and defining the needs

The putative peculiarities of island insects and the factors important in their conservation are noted. Endemism and speciation lessons from island insects have contributed significantly to wider understanding of aspects of insect diversification. The twin complexes of threats to island insects involve (1) internal processes, essentially habitat changes by human activity, and their consequences and (2) externally-imposed effects from alien invasive species, both of these operating in environments that may lack much of the buffer capability present in larger continental areas or in richer communities. Many island insects now persist only in small inaccessible remnant habitats, and protecting these is a key theme in planning insect conservation on islands. The possible effects of climate change may be severe, particularly on ‘low islands’ such as many coral cays.

Exotic Pine Plantations in Victoria, Australia: A Threat to Epigaeic Beetle (Coleoptera) Assemblages?

Ground-dwelling invertebrates were sampled by pitfall traps over a 14 week period in parent eucalypt forest and three stages of exotic Pinus radiata plantations established after forest clearance in central Victoria. The four treatments each yielded numerous beetle morphospecies, and the assemblages corresponded only partially with the understorey vegetation. More than 200 beetle morphospecies were captured during this short survey, with 30 found in all four treatments; few morphospecies were abundant (only five with >100 individuals in a total of 3382 beetles). Each treatment had unique morphospecies, but all were rich, with the lowest diversity being 91 morphospecies (young pines). These data confirm that beetle diversity can remain substantial in exotic softwood plantations, but considerable care is needed to interpret this apparent diversity in relation to forest management and the effect of replacement of native forests by exotic taxa.

Notes on Neotropical Zoraptera, with descriptions of two new species

Characters used un specific identification of Zoraptera are briefly discussed. A list of Neotropical species is given, and the difficulties of associating sexes of some species outlined. Two new species are described and figured (Zorotypus weidneri sp.n., ♂, ♀, Brazil; Z.hamiltoni sp.n., ♂, ♀, Colombia) and additional records and information given on Z.shannoni Gurney (♂, Brazil) and Z.huxleyi Bolivar y Pieltain & Coronado G (♂, ♀, recorded from Brazil for the first time).