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The impact of demographic parameters on the genetic population structure and viability of organisms is a long-standing issue in the study of fragmented populations. Demographic and genetic tools are now readily available to estimate census and effective population sizes and migration and gene flow rates with increasing precision. Here we analysed the demography and genetic population structure over a recent 15-year time span in five remnant populations of Cabanis's greenbul (Phyllastrephus cabanisi), a cooperative breeding bird in a severely fragmented cloud forest habitat. Contrary to our expectation, genetic admixture and effective population sizes slightly increased, rather than decreased between our two sampling periods. In spite of small effective population sizes in tiny forest remnants, none of the populations showed evidence of a recent population bottleneck. Approximate Bayesian modelling, however, suggested that differentiation of the populations coincided at least partially with an episode of habitat fragmentation. The ratio of meta-Ne to meta-Nc was relatively low for birds, which is expected for cooperative breeding species, while Ne /Nc ratios strongly varied among local populations. While the overall trend of increasing population sizes and genetic admixture may suggest that Cabanis's greenbuls increasingly cope with fragmentation, the time period over which these trends were documented is rather short relative to the average longevity of tropical species. Furthermore, the critically low Nc in the small forest remnants keep the species prone to demographic and environmental stochasticity, and it remains open if, and to what extent, its cooperative breeding behaviour helps to buffer such effects., (© 2015 John Wiley & Sons Ltd.)

Many disasters that occur throughout the world remain largely under-reported, frequently because they began a number of years ago, and have become "chronic" or "long term." Yet, in their vulnerability, the affected populations are no less deserving of humanitarian aid than those involved in the more acute, sudden disasters that make a major impact in the media. Aid providers need to direct their efforts at enabling populations to build their capacity and decrease their vulnerability, thus enhancing their preparedness for any future disaster. This article considers the importance of paying careful regard to the vulnerability, capacities, and disaster preparedness of people affected by these long-term disasters. Vulnerability, capacity, and disaster preparedness are examined specifically in the context of food shortages and malnutrition, with particular reference to the long-term disaster in the African country of Kenya.