Factors affecting wetland ground beetle (Carabidae) assemblages: how important are habitats, conservation designations and management?

Abstract

We investigated factors affecting wetland carabid diversity and assemblage dynamics as part of the first national survey in the Republic of Ireland. Species richness was significantly different among habitat types and was significantly higher on designated as opposed to undesignated land. However, red‐data‐book species richness was significantly higher on undesignated land, highlighting the importance of land outside the conservation network. This was largely due to the prominence of Carabus clatratus L. outside designated areas and often on high‐disturbance land. Management for species of conservation interest outside of designated areas, and in concert with existing agri‐environment, schemes is apparent. Shannon's entropy was significantly greater on grazed as compared to ungrazed land, further highlighting the importance of management in maintaining high diversity carabid assemblages, which should be included in future conservation plans for ground dwelling invertebrates. Models of diversity partitioning for a number of variables (location, habitat type, perceived habitat quality, designation status and grazing) indicated a significantly lower α (within sites) diversity than would be expected by chance, but significantly higher β diversities, indicating that diversity was significantly structured among rather than within groups of these variables. A multi‐response permutation procedure, however, indicated that carabid assemblage composition was significantly, but weakly, structured in terms of domestic grazing, location and both broad and narrow habitat classifications. This indicates a difference in the significance of the effects of variables on beta‐diversity as assessed through partitioning using a dimensionless value and assessments based on the pairwise dissimilarity matrix.

Identifying factors associated with the success and failure of terrestrial insect translocations

“…This type of data would be obtainable through the circulation of a survey to translocation practitioners, as demonstrated in a review of mammal and bird translocations in which respondents ranked habitat quality as "excellent", "good" or "fair or poor" (Griffith et al, 1989). However, it can be particularly challenging to gauge habitat quality for insects, as highlighted in Williams et al, (2014), in which conservation professionals often ranked habitat quality for carabid beetles as both "good" and "bad" in areas where there was maximal diversity. The subjectivity of habitat quality assessment suggests that, although this variable is of importance, the method by which this data is collected requires careful consideration of how to maximise objectivity.…”

Ecology of Terrestrial Arthropods in Freshwater Wetlands

“…However, efforts to use terrestrial arthropods for wetland bioassessment show more promise. While bioassessment in aquatic habitats focuses on whole communities, workers using terrestrial wetland arthropods tend to focus on specific groups, with Carabidae being the most widely used (e.g., 20,28,31,49,54,67,85,86,127,141). Spiders (112,114,132) and lepidopterans (19,79,93,113,137) are used occasionally.…”

Protected species and development control: the merits of widespread invertebrate species in the European Habitats Directive and UK legislation

“…A high proportion of species are present within designated sites, such as 116 of 120 endemic water beetles in Spain and all three endemic slugs of Crete. Conversely, criticism of the Natura 2000 network includes limited evidence that designation results in improved management even for the designated species (Williams et al, 2014;Zehetmair et al, 2015) and the relatively greater abundance (but not absolute restriction) of some wetland species outside of the Natura 2000 network (Williams et al, 2014).…”