Information theoretic approaches and model averaging are increasing in popularity, but this approach can be difficult to apply to the realistic, complex models that typify many ecological and evolutionary analyses. This is especially true for those researchers without a formal background in information theory. Here, we highlight a number of practical obstacles to model averaging complex models. Although not meant to be an exhaustive review, we identify several important issues with tentative solutions where they exist (e.g. dealing with collinearity amongst predictors; how to compute model‐averaged parameters) and highlight areas for future research where solutions are not clear (e.g. when to use random intercepts or slopes; which information criteria to use when random factors are involved). We also provide a worked example of a mixed model analysis of inbreeding depression in a wild population. By providing an overview of these issues, we hope that this approach will become more accessible to those investigating any process where multiple variables impact an evolutionary or ecological response.

Studies evaluating the impact of inbreeding depression on population viability of threatened species tend to focus on the effects of inbreeding at a single life-history stage (e.g., juvenile survival). We examined the effects of inbreeding across the full life-history continuum, from survival up to adulthood, to subsequent reproductive success, and to the recruitment of second-generation offspring, in wild Takahe ( Porphyrio hochstetteri ) by analyzing pedigree and fitness data collected over 21 breeding seasons. Although the effect size of inbreeding at individual life-history stages was small, inbreeding depression accumulated across multiple life-history stages and ultimately reduced long-term fitness (i.e., successful recruitment of second-generation offspring). The estimated total lethal equivalents (2B) summed across all life-history stages were substantial (16.05, 95% CI 0.08-90.8) and equivalent to an 88% reduction in recruitment of second-generation offspring for closely related pairs (e.g., sib-sib pairings) relative to unrelated pairs (according to the pedigree). A history of small population size in the Takahe could have contributed to partial purging of the genetic load and the low level of inbreeding depression detected at each single life-history stage. Nevertheless, our results indicate that such "purged" populations can still exhibit substantial inbreeding depression, especially when small but negative fitness effects accumulate across the species' life history. Because inbreeding depression can ultimately affect population viability of small, isolated populations, our results illustrate the importance of measuring the effects of inbreeding across the full life-history continuum.

Continuous inbreeding exposes deleterious recessive alleles to selection and can thereby lead to partial purging of the genetic load and reduced inbreeding depression. Purging has been well documented in experimental laboratory populations, but evidence of reduced inbreeding depression due to purging in wild populations is largely lacking. This study examines the inbreeding load associated with juvenile survival at a protected island site of a bottlenecked population of the Stewart Island robin Petroica australis rakiura. Based on a complete pedigree of the island population, we found little evidence that inbreeding coefficients explained any additional variation in juvenile survival, once demographic factors such as the effects of density, timing of fledging and age of mother were taken into account. Lethal equivalents, a standardized measure of the strength of inbreeding depression, were close to zero (B=0.24, 95% CI=À1.92-1.04, n= 326) and lower than that documented for an island population of a widespread congener (B= 6.71, 95% CI=À0.66-14.08, n= 238) and for several other species for which significant inbreeding depression was detected (B= 1.30-7.47). There are several reasons as to why studies can fail to detect pedigree-based inbreeding depression in wild populations, but evidence presented here of low lethal equivalents and relatively high survival of both inbred and non-inbred juveniles are consistent with a population that has undergone partial purging of its genetic load during historical population bottlenecks. Although our study does not imply a complete absence of inbreeding depression, it is one of the first studies of a wild population where weak inbreeding depression for juvenile survival appears to be associated with a prolonged bottleneck.

Local Authority administered Demand Responsive Transport (DRT) schemes are increasingly prevalent in England and Wales, partly as a result of the growth in the availability of Government funding. However insufficient research has been undertaken into the nature of these schemes and their performance making it difficult to predict their future role. In this respect, a survey was undertaken in order to collect data on the background, operation and performance of DRT schemes in England and Wales. It found that DRT schemes are often designed in an attempt to tackle social problems caused by poor accessibility, and that they took time to become established, to achieve their objectives and to reach an acceptable performance in terms of subsidy level. The paper concludes that Local Authority led DRT schemes have a role to play but that lessons learnt from schemes currently in operation must be heeded by those contemplating new scheme development.

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