Species selected as flagships to promote conservation activities around the world are typically well known and charismatic mega-fauna. Unfortunately this limits the scope for applying the concept as some critical areas for biodiversity conservation, such as tropical islands, lack such species. In this study, we explore the potential to apply the concept of 'tourism flagship species' to tropical island birds of the Seychelles, an archipelago of considerable importance for conservation that is highly dependent on international tourism. In particular we wish to identify which species attributes are most influential with regard to their potential for fundraising among international tourists. Using a choice experiment approach and using state-of-the-art econometric methods, we found that conservation attributes and physical appearance of the bird species are both important in terms of raising funds for conservation. Nevertheless, conservation attributes ranked higher in the respondents preferences. Our results suggest that there is considerable potential for a variety of species to effectively act as flagships in developing nations that are dependent on international tourism and rich in biodiversity but lack charismatic fauna.

Temporal variation in survival, fecundity, and dispersal rates is associated with density-dependent and density-independent processes. Stable natural populations are expected to be regulated by density-dependent factors. However, detecting this by investigating natural variation in density is difficult because density-dependent and independent factors affecting population dynamics may covary. Therefore, experiments are needed to assess the density dependence of demographic rates. In this study, we investigate the effect of density on demographic rates of the Seychelles Warbler (Acrocephalus sechellensis). This species, endemic to a few islands in the Indian Ocean, went through a severe population bottleneck in the middle of the last century, with only approximately 30 individuals left on one small island, but has since recovered. Our monitoring shows that since reaching the island's carrying capacity, population density has remained stable. However, we detected neither density-dependent reproduction nor survival on the basis of natural density variation during this stable period. For conservation reasons, new populations have been established by transferring birds to nearby suitable islands. Using the change of numbers during the process of saturation as a natural experiment, we investigated whether we can detect regulation of numbers via density-dependent survival and reproduction within these new populations. We found that populations were mainly regulated by density-dependent reproduction, and not survival. Variation in density between islands can be explained by food abundance, measured as insect density. Islands with the highest insect densities also had the highest bird densities and the largest breeding groups. Consequently, we suggest that the density-dependent effect on reproduction is caused by competition for food.

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In many species, territory ownership is a prerequisite for reproduction; consequently, factors that affect success in territory acquisition can have a large impact on fitness. When competing for territories, some individuals may have an advantage if, for example, they are phenotypically superior or more familiar with the site than others. The relative importance of the many factors involved in territory acquisition is, at present, unclear. We studied patterns of natural territory acquisition in a closed and saturated population of Seychelles warblers. Furthermore, by removing breeders, we experimentally investigated the relative importance, to territory acquisition, of a range of factors and assessed whether this differed between the sexes. In both sexes, the main route to natural territory acquisition was to disperse from the natal territory to immediately claim a vacant dominant position. Males were older than females when acquiring a territory for the first time. In the removal experiment, for both sexes, the proximity of an individual's natal territory to a vacant dominant position was positively related to the individual's chance of claiming the vacancy. Older males were more likely to gain an experimental vacant dominant position than were young males, whereas age did not affect territory acquisition in females. In the Seychelles warbler, the degree of intrasexual competition for territory ownership may be stronger for males than for females because territory ownership is a prerequisite for male reproduction, whereas females can reproduce on their natal territory. In such competition, young males subsequently lose out to older ones.

Aim  We use parametric biogeographical reconstruction based on an extensive DNA sequence dataset to characterize the spatio‐temporal pattern of colonization of the Old World monarch flycatchers (Monarchidae). We then use this framework to examine the role of dispersal and colonization in their evolutionary diversification and to compare plumages between island and continental Terpsiphone species. Location  Africa, Asia and the Indian Ocean. Methods  We generate a DNA sequence dataset of 2300 bp comprising one nuclear and three mitochondrial markers for 89% (17/19) of the Old World Monarchidae species and 70% of the Terpsiphone subspecies. By applying maximum likelihood and Bayesian phylogenetic methods and implementing a Bayesian molecular clock to provide a temporal framework, we reveal the evolutionary history of the group. Furthermore, we employ both Lagrange and Bayes‐Lagrange analyses to assess ancestral areas at each node of the phylogeny. By combining the ancestral area reconstruction with information on plumage traits we are able to compare patterns of plumage evolution on islands and continents. Results  We provide the first comprehensive molecular phylogenetic reconstruction for the Old World Monarchidae. Our phylogenetic results reveal a relatively recent diversification associated with several dispersal events within this group. Moreover, ancestral area analyses reveal an Asian origin of the Indian Ocean and African clades. Ancestral state reconstruction analyses of plumage characters provide an interpretation of the plumage differentiation on islands and continents. Ancestral plumage traits are inferred to be close to those of the Asian paradise‐flycatcher (Terpsiphone paradisi), and island species display a high degree of plumage autapomorphy compared with continental species. Main conclusions  Terpsiphone paradisi is polyphyletic and comprises populations that have retained the ancestral plumage of the widespread Terpsiphone genus. The genus appears to have colonized south‐west Asia, the Indian Ocean and Africa from eastern Asia. The phylogeny and divergence time estimates indicate multiple simultaneous colonizations of the western Old World by Terpsiphone. These results reinforce a hypothesis of range expansions of a Terpsiphone paradisi‐like ancestor into eastern Asia and the western Old World.

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Re-introduction is an important tool for recovering endangered species; however, the magnitude of genetic consequences for re-introduced populations remains largely unknown, in particular the relative impacts of historical population bottlenecks compared to those induced by conservation management. We characterize 14 microsatellite loci developed for the Seychelles paradise flycatcher and use them to quantify temporal and spatial measures of genetic variation across a 134-year time frame encompassing a historical bottleneck that reduced the species to ~28 individuals in the 1960s, through the initial stages of recovery and across a second contemporary conservation-introduction-induced bottleneck. We then evaluate the relative impacts of the two bottlenecks, and finally apply our findings to inform broader re-introduction strategy. We find a temporal trend of significant decrease in standard measures of genetic diversity across the historical bottleneck, but only a nonsignificant downward trend in number of alleles across the contemporary bottleneck. However, accounting for the different timescales of the two bottlenecks (~40 historical generations versus <1 contemporary generation), the loss of genetic diversity per generation is greater across the contemporary bottleneck. Historically, the flycatcher population was genetically structured; however, extinction on four of five islands has resulted in a homogeneous contemporary population. We conclude that severe historical bottlenecks can leave a large footprint in terms of sheer quantity of genetic diversity lost. However, severely depleted genetic diversity does not render a species immune to further genetic erosion upon re-introduction. In some cases, the loss of genetic diversity per generation can, initially at least, be greater across re-introduction-induced bottlenecks.

The only microchiropteran endemic to the granitic Seychelles, the sheath-tailed bat Coleura seychellensis, is categorized as Critically Endangered on the IUCN Red List. Using bat detectors, the islands of Mahé, Praslin and La Digue were surveyed to establish the current distribution of this species. Although two new roosts were discovered on Mahé, no bats were observed on Praslin and La Digue, and the range of C. seychellensis appears to have further contracted in the last 2 decades. A total of 19 C. seychellensis were counted emerging from or entering three roosts in boulder caves on Mahé during 18 evenings of observations. The bats foraged in open coastal habitat, some of it anthropogenic, and their echolocation calls were also characteristic of bats feeding in open habitat. This study provides no evidence that C. seychellensis is dependent on forest or wetland for foraging. Dietary analysis indicated that C. seychellensis feeds on Coleoptera, Lepidoptera and Diptera. A public education programme to highlight the conservation status of the bat and the consequences of roost disturbance is recommended, together with the urgent need for legal protection of the bats and their roosts.