NICOLAS, Jean-Hervé, o.p., Contemplation et vie contemplative

The habitat is the basic unit for developments in life history, population dynamics, landscape ecology and conservation of organisms. It is frequently treated as a particulate, invariant and homogeneous entity (a patch). Here we examine the implications of using this concept of habitat in butterfly biology. In doing so, we suggest the alternative approach of applying a functional resource-based concept of habitat. This recognises the fundamental requirements of organisms, consumables and utilities, the latter describing suitable environmental conditions as well as essential substrates. We argue that a resource-based concept is critical for butterfly conservation and call for the development of a resource database on butterfly biology

Support for mending the matrix: resource seeking by butterflies in apparent non-resource zones

In conserving organisms, a bipolar view has generally been adopted of landscapes, in which resources are allocated to patches of habitats and the matrix ignored. Allocating additional resources to the matrix would depend on two conditions: first, that organisms search for resources in landscapes regardless of differences in vegetation types and resource availability; second, that when resources occur in the matrix they are used by species. Behavioural data linked to biotope and substrate types, on three pierid species (Pieris brassicae, P. rapae, P. napi), have been examined to explore the relationship between flight modes and resource availability. Search flight and resource use, taken as measures of resource quests, occur extensively in all biotopes and over all substrates in addition to direct linear flight, more typical of butterflies when migrating between habitat units. Resource seeking and using even exceed direct flight in some biotopes that have been regarded generally as lacking in resources for these butterflies. For example, such is the case for P. brassicae in woodland and for P. rapae in scrub. This finding supports the view for repairing the matrix and enhancing the general countryside outside habitat patches with resources increasingly being made for organisms. The proviso is that species’ requirements are adequately researched and resourced so as not to become sinks

The effects of visual apparency on bias butterfly recording and monitoring

A basic assumption in conservation is that comparable data are available for species to facilitate risk assessment of extinction. However, the capacity for carrying out cross-species comparisons for abundances and distributions among butterflies depends on the absence of bias in recording and monitoring or the existence of appropriate techniques for removing bias. Here, we investigate potential bias in cross-species comparisons for the apparency of butterfly adults (wing colour, size and behaviour) in three pivotal UK datasets: dates of discovery, Butterfly Monitoring Scheme (BMS) transect measures of abundance and Butterflies for the New Millennium (BNM) national recording scheme. Bias is found in all three datasets. Discovery date is affected by wing colour and size, BNM recording by adult behaviour and wing colour and BMS monitoring by adult behaviour. The nature and degree of bias differs between uncorrected cross-species comparisons and those with the application of phylogenetic contrasts. The findings urge caution in using these datasets for cross-species analysis without improvements and standardisation of recording and monitoring and the development of techniques to adjust for biases, in particular the use of suitable comparative techniques. The latter requires the construction of a molecular phylogeny for butterflies