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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2009.03.011 Byline: Lior Davidovitch (a), Richard Stoklosa (b), Jonathan Majer (c), Alex Nietrzeba (c), Peter Whittle (d)(e), Kerrie Mengersen (d)(e), Yakov Ben-Haim (a) Abstract: Surveillance for invasive non-indigenous species (NIS) is an integral part of a quarantine system. Estimating the efficiency of a surveillance strategy relies on many uncertain parameters estimated by experts, such as the efficiency of its components in face of the specific NIS, the ability of the NIS to inhabit different environments, and so on. Due to the importance of detecting an invasive NIS within a critical period of time, it is crucial that these uncertainties be accounted for in the design of the surveillance system. We formulate a detection model that takes into account, in addition to structured sampling for incursive NIS, incidental detection by untrained workers. We use info-gap theory for satisficing (not minimizing) the probability of detection, while at the same time maximizing the robustness to uncertainty. We demonstrate the trade-off between robustness to uncertainty, and an increase in the required probability of detection. An empirical example based on the detection of Pheidole megacephala on Barrow Island demonstrates the use of info-gap analysis to select a surveillance strategy. Author Affiliation: (a) Faculty of Mechanical Engineering, Technion - Israel Institute of Technology, Haifa 32000, Israel (b) Chevron, Perth WA 6000, Australia (c) Department of Environmental Biology, Curtin University of Technology, Perth WA 6845, Australia (d) Faculty of Science, Queensland University of Technology, Brisbane QLD 4001, Australia (e) Cooperative Research Centre for National Plant Biosecurity, Bruce ACT 2617, Australia Article History: Received 10 July 2008; Revised 21 February 2009; Accepted 19 March 2009

Highlights: [•] Ant spp. richness increased from inside (I), edge (E), outside (O) Monsoon Vine Thickets. [•] Distinctly different ant assemblages were found inside the Monsoon Vine Thickets. [•] Species inside prefer cool dense vegetation, those at the edges prefer open habitat. [•] I, E and O differences matched less litter depth and canopy cover, and increased fire. [•] Indigenous rangers conducted the study and will use results for management. [ABSTRACT FROM AUTHOR]

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Abstract: Taxonomic impediments require us to know if simpler approaches such as using higher taxa or habitat surrogates can help assess the needs of invertebrates when managing forests. This study tests whether higher taxon (families for species) and habitat (vegetation structure for species and families) surrogates might assist in determining the effects of prescribed burning on spiders. Spiders were sampled at sites representing a chronosequence of increasing ages since burning (0, 3, 6 and 9 years) by pitfall trapping and vacuuming from understorey vegetation in the South-west Botanical Province of Australia; a global biodiversity hotspot. Reassembly followed a similar pattern for both the richness of species and families. Immediately following burning, mean richness of families and species was low (8.75 and 14.5, respectively). By 3 years, however, there were significant increases in familial and species richness (13.25 and 23.75, respectively). Thereafter, taxon richness remained constant. Multiple regressions suggested habitat variables potentially influencing family and species richness were litter depth, bare ground (%), the density of dead vegetation (0–100cm high), and the density of live vegetation (40–140cm). The first three of these variables correlated significantly with time since burning, suggesting these components of habitat structure are useful predictors of taxon richness for spiders following fire. For assemblage composition, the congruence in post-fire response patterns between taxonomic ranks was highly significant, although the amount of variation explained was low (Rho<0.55). In the first 9 years post-fire, there was a significant shift in the taxonomic composition of spiders at family, but not specific, rank. Family composition at recently burnt sites differed significantly from that at sites burnt 9 years previously. Correlated with assemblage composition were litter depth, bare ground, and the density of live vegetation (0–40cm above the ground). However, the best correlation obtained by any combination of habitat variables with assemblage composition (Rho<0.317) was less than that obtained by using family level data. We conclude, therefore, that where resources are limited and there is a need to determine the effects of forest management practices on invertebrates using surrogates, identifying spiders to higher taxa is better than relying on habitat structure. [Copyright &y& Elsevier]

Abstract: Like most ecosystems of the world, tropical dry forests of the central coast of the Gulf of Mexico are inadequately preserved. Given that reserve expansion is unlikely, it is imperative that the conservation capacity of the matrix surrounding reserves is enhanced. Here, we examine the habitat value of isolated pasture trees and patches of secondary regrowth in terms of their terrestrial and arboreal ant assemblages in both a wet and dry season. These simplified wooded systems increase species densities within the agricultural matrix and provide habitat for some forest ant species. Estimated species richness of arboreal ants was particularly low on isolated trees, highlighting an important limitation. This was not the case for terrestrial ants, which were particularly species rich under isolated trees. We also found that the inter-site variations in species densities and similarity to the forest ant assemblage for terrestrial and arboreal strata were not correlated, suggesting that responses to restoration may not be as uniform as often thought. This has important implications for the use of indicator taxa in suggesting the response of other taxa. In terms of species composition, neither secondary regrowth nor isolated trees were appropriate replacements for forest fragments, even though the studied forest fragments were small (13–32ha). The ant assemblages did not exhibit a seasonal change in composition. However, season influenced the contrast between habitats, with isolated trees being more distinct from pasture, and regrowth more closely resembling forests, during the wet season. Microclimatic variables indicate that the forests were least affected by the tropical dry season, and this may contribute to their characteristic fauna. We conclude that even small forest patches make a unique contribution to landscape conservation and that, where reserves are limited, conscientious management of the landscape matrix may provide some species with sufficient new habitat to survive outside of reserve systems. These conclusions are influenced by both season and strata studied. [Copyright &y& Elsevier]

• Biodiversity surrogates provide meaningful information at a lower cost and effort. • Ants are often used in such environmental assessments. • We seek a useable substitute surrogate for taxonomic and functional ant diversity. • For this, we tested four potential ant surrogates at 65 Atlantic rainforest sites. • Of the species and functional group surrogates, mixed-level was the best. Comprehensive biodiversity inventories are expensive and time-consuming to achieve, especially for groups of megadiverse organisms. One approach to resolve such situations is to utilize biological substitutes, referred to as surrogates. A surrogate should provide meaningful information at a lower cost and/or effort than the original level of resolution. Studies have shown that species richness is often not the best or most appropriate component or predictor of biodiversity. Functional diversity can be used as a measurement of the ecological differentiation between habitats or between biological functions. We evaluated the use of several taxonomic metrics as potential surrogates for leaf-litter ant assemblages distributed in 65 Atlantic rainforest sites. Our goal was to find reliable and economic substitutes for both taxonomic and functional leaf-litter ant diversity and composition. We tested four potential surrogate approaches for taxonomic metrics and three for functional group metrics. Additionally, we also evaluated the time and costs involved. We used a large leaf-litter ant database that comprises 364 ant species, respectively classified into 13 or 26 ant functional groups based on either a general and specific resolution. Subfamily was found to be an unacceptable surrogate for both taxonomic and functional group metrics. Mixed-level and indicator taxa metrics were rated as 'excellent' taxonomic surrogates. Mixed-level and genus metrics were rated as 'excellent' or 'acceptable' functional group surrogates when considering the most general functional resolution, while mixed-level and genus were considered as 'excellent' surrogates when considering the more specific resolution. The monetary and time costs to identify ants to genus level were lower than those using indicator taxa and mixed-level metrics. The use of a certain higher taxon functional and taxonomic surrogates allows a reduction of survey and analysis costs while still enabling the analysis of biological diversity from the taxonomic and functional point of view. [ABSTRACT FROM AUTHOR]

Abstract: Insects, particularly ants, are good bioindicators of the state of ecosystems. Nevertheless, incorporating them into conservation surveys is expensive due to problems associated with their identification, which is exacerbated by the fact that there are fewer and fewer taxonomists working today. “Taxonomic sufficiency” (TS), which identifies organisms to a level of taxonomic resolution sufficient enough to satisfy the objectives of a study, has never been applied to Neotropical ant communities. We analysed five Neotropical datasets representing ant assemblages collected with different sampling methods in various habitats. We first treated them using two complementary and cumulative TS methods, higher-taxon and “indicator taxa” surrogacies, before testing a new approach called “mixed-level method” that combines the two previous approaches. For the higher-taxon surrogacy, we showed that, above species, genus is the most informative taxonomic level. Then, mixed-level method provided more information on ant assemblages than did the two others, even though the “indicator taxa” surrogacy was based on relevant indicator genera. Although habitat type has no effect on its efficiency, this new method is influenced by the dataset structure and the type of sampling method used to collect data. We have thus developed a new method for analyzing Neotropical ant faunas that enables the taxonomic work linked to the identification of problematic species to be significantly reduced, while conserving most of the information on the ant assemblage. This method should enhance the work of Neotropical entomologists not specialised in taxonomy, particularly those concerned with biological conservation and indication. [ABSTRACT FROM AUTHOR]

Abstract: Seed dispersal is a fundamental life history trait in plants. Although the recent surge of interest in seed dispersal by ants (myrmecochory) has added greatly to knowledge on the ecology of seed dispersal and ant–plant mutualisms, myrmecochory also represents a unique opportunity to examine the links between seed dispersal and evolution in flowering plants. Here we review the taxonomic, phylogenetic and biogeographic distribution of myrmecochory in flowering plants. Myrmecochory is mediated by elaiosomes, i.e., lipid-rich seed appendages that attract ants and serve as rewards for dispersal. We surveyed the literature for evidence of elaiosomes in angiosperm plants to estimate the global prevalence of myrmecochory. We then searched the literature for phylogenetic reconstructions to identify myrmecochorous lineages and to estimate the minimum number of independent evolutionary origins of myrmecochory. We found that myrmecochory is present in at least 11000 species or 4.5% of all species, in 334 genera or 2.5% of all genera and in 77 families or 17% of all families of angiosperm plants. We identified at least 101, but possibly up to 147, independent origins of myrmecochory. We estimated three or more origins in 13 families and found that at least half the genera are myrmecochorous in 10 families. Most myrmecochorous lineages were Australian, South African or northern temperate (Holarctic). A mapping of families containing myrmecochorous genera on a dated angiosperm supertree showed that myrmecochory has evolved in most of the major angiosperm lineages and that it is more frequent in younger families (crown group age <80 million years) than in older ones. We suggest that the relatively low physiological and energetic costs of producing an elaiosome and the consistent selective benefits of myrmecochory (dispersal, protection from seed predators and fire, safe and nutrient-rich microsites) explain the numerous evolutionary and developmental origins of myrmecochory in angiosperm plants, and we propose that elaiosomes thus provide one of the most dramatic examples of convergent evolution in biology. [Copyright &y& Elsevier]

• Globally, our knowledge is focused on a limited set of taxonomic groups. • We know more about small and young areas, degraded by mining or agriculture. • Planted or seeded areas monitored by diversity or richness indexes are the most common investigations. • Groups evaluated and functional group approaches have been increasing in recent years. • Incomplete-Puzzle hypothesis can be a more realistic approach in restoration scenarios. Biodiversity promotion activities, such as ecological restoration, are recognized as instruments to arrest and mitigate the diminishing health of ecosystems. The restoration of fauna is a fundamental component of this process but, despite this, there are few studies that compile and discuss the knowledge produced on this topic. Hence, by seeking a general understanding of what we currently know about terrestrial invertebrates as bioindicators in restored ecosystems, the present work sought to organize knowledge in such a way as to indicate gaps and opportunities for both researchers and restorers. To this end, we searched for topics associated with restoration ecology in the Web of Science database, identifying which invertebrate groups have been studied in relation to intrinsic characteristics of ecological intervention, including type of biome, type of disturbance, restoration technique, age, project size, and indices used. We found 154 studies published between 1995 and 2018: 93.5% of which were from 2002 onwards. We detected a growing number of studies and a tendency to evaluate functional groups. Moreover, there was a high concentration of studies within a few taxonomic groups, notably Hymenoptera (Formicidae), Coleoptera, and Lepidoptera. Many of the restoration scenarios are poorly studied, for example, in temperate coniferous forests or taiga biomes, previous disturbances caused by pollution or urbanization, under certain restoration techniques such as brushwood transposition, and investigations in large or old areas. There was also a paucity of information concerning community or population-level measures of restoration success, such as the structure of communities, biomass, and dominance. We discuss some consequences of these knowledge gaps. Finally, we indicate which taxonomic groups have been evaluated in relation to each restoration characteristic considered, resulting in guidance for those wishing to engage in research and monitoring of such organisms during the restoration process. [ABSTRACT FROM AUTHOR]