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Mosquito surveillance programmes are essential to assess the risks of local vector-borne disease outbreaks as well as for early detection of mosquito invasion events. Surveys are usually performed with traditional sampling tools (i.e., ovitraps and dipping method for immature stages or light or decoy traps for adults). Over the past decade, numerous studies have highlighted that environmental DNA (eDNA) sampling can enhance invertebrate species detection and provide community composition metrics. However, the usefulness of eDNA for detection of mosquito species has, to date, been largely neglected. Here, we sampled water from potential larval breeding sites along a gradient of anthropogenic perturbations, from the core of an oil palm plantation to the rainforest on São Tomé Island (Gulf of Guinea, Africa). We showed that (i) species of mosquitoes could be detected via metabarcoding mostly when larvae were visible, (ii) larvae species richness was greater using eDNA than visual identification and (iii) new mosquito species were also detected by the eDNA approach. We provide a critical discussion of the pros and cons of eDNA metabarcoding for monitoring mosquito species diversity and recommendations for future research directions that could facilitate the adoption of eDNA as a tool for assessing insect vector communities.

Many species are difficult to study either due to their rarity, elusiveness, difficult access to their area of occurrence, or any combination of these. This can be particularly problematic for threatened species. Passive acoustic monitoring (PAM) is a recently developed survey technique that has shown great potential in addressing this problem for species that communicate through vocalizations. However, the large amount of data it generates can be difficult to process manually. Here, we present an entirely automatic workflow to record and detect the vocalizations of a bird species that is both elusive (nocturnal) and restricted to difficult terrain in the most remote rainforests of an oceanic island: the recently discovered Principe Scops-Owl. Specifically, we evaluated (i) the performance of the workflow to monitor the presence of the owl, (ii) we assessed the most suitable time for monitoring it; and (iii) we examined the potential of this species to present detectable vocal individual signatures. For 12 days, we deployed omnidirectional recording stations (AudioMoth devices) in 72 points along 10 transects that were surveyed during one night at the same time by observers in the field. We trained TADARIDA, a machine learning software toolbox, to automatically detect owl calls. Results on the presence of the owl per site were similar for both methods. The automatic workflow showed that the owl is active during the whole night and the PAM recording setting should encompass at least the 21-23 h interval. Possibly, vocalizations had individual signatures – but the small sample size and temporal window prevented a definite conclusion. The automatic workflow developed here is an efficient method to monitor the Principe Scops-Owl and can be easily adapted for other elusive vocal species.

While populations of the Endangered Grey Parrot Psittacus erithacus have collapsed across its range, the species remains remarkably abundant on the island of Príncipe, Gulf of Guinea. We examine how aspects of its ecology interplay with local environmental conditions, to inform conservation strategies for this species and other large parrots. On Príncipe, parrots breed in large trees of common species, with nest densities (42 ± 34 km−2) greatly exceeding those for any comparably sized parrot. Productivity is high (1.9 chicks per cavity), probably reflecting the absence of nest competitors and predators. Food sources are abundant and much of the island is inaccessible to trappers, so many nests are successful each year. Historically harvest has involved taking only chicks from trees in a few traditional patches. These conditions have combined to allow Grey Parrots to thrive on Príncipe, while elsewhere nest trees are timber targets, nest competition and nest predation are likely to be more intense, trapping is indiscriminate, and few areas remain unexploited by trappers. Preservation of large trees as breeding refugia, and vigilance against the indiscriminate trapping of adult birds, are identified as key conditions to stabilize and recover mainland Grey Parrot populations and indeed large parrots generally, given their very similar ecological traits and anthropogenic circumstances.

Sister species occurring sympatrically on islands are rare and offer unique opportunities to understand how speciation can proceed in the face of gene flow. The São Tomé grosbeak is a massive-billed, ‘giant’ finch endemic to the island of São Tomé in the Gulf of Guinea, where it has diverged from its co-occurring sister species the Príncipe seedeater, an average-sized finch that also inhabits two neighbouring islands. Here, we show that the grosbeak carries a large number of unique alleles different from all three Príncipe seedeater populations, but also shares many alleles with the sympatric São Tomé population of the seedeater, a genomic signature signifying divergence in isolation as well as subsequent introgressive hybridization. Furthermore, genomic segments that remain unique to the grosbeak are situated close to genes, including genes that determine bill morphology, suggesting the preservation of adaptive variation through natural selection during divergence with gene flow. This study reveals a complex speciation process whereby genetic drift, introgression, and selection during periods of isolation and secondary contact all have shaped the diverging genomes of these sympatric island endemic finches.Abstract Figure

The oceanic islands of the Gulf of Guinea hold extraordinary levels of endemism across many taxonomic groups. Biodiversity surveys are still uncovering species new to science, and much work remains to be done on the evolution, ecology, and conservation of this unique biological heritage. The next 10 years will be crucial to find and implement development strategies that can respond to the needs of the islands’ inhabitants while sustaining the biodiversity and ecosystem functions on which they depend. We outline seven priority areas that need to be addressed on the path for a thriving future for both people and biodiversity.

Although birds have always been one of the best-known taxa on the Gulf of Guinea oceanic islands, our understanding of their ecology and evolution has increased substantially in the last two decades. Intensive field-based surveys have allowed the first detailed island-wide distribution maps for most species and a much better grasp of habitat associations, highlighting the importance of native forests for many of the endemic birds. Molecular data have provided important insights into evolutionary history, leading to an extensive revision of the taxonomy of the islands’ endemic avifauna. Most speciation events are much more recent than the age of the islands, indicating a high species turn-over that is likely explained by the islands’ history of intense volcanic activity and their moderate distances to the mainland. These islands have the highest accumulation of endemic bird species for small oceanic islands: at least 29 endemic species occur in three islands with a total area of just over 1000 km2. This may be explained by their particular geographic location: offshore from a species-rich continent at distances that allowed the colonization and evolution in isolation of many distinct lineages. All these contributions are now being used to ensure bird conservation, through updated species conservation status and species action plans for the most threatened species, and also to promote the conservation of the native forests on which most of the endemic birds depend.

As with most archipelagos, geography played a central role in the assembly and evolution of the endemic-rich biological communities of the Gulf of Guinea oceanic islands. The islands are located at moderate distances from the species-rich African continent that surrounds them to the east and north. This proximity facilitated colonization by many branches of the tree of life, but gene flow between the islands and continent was low enough that many lineages evolved in isolation once they reached the archipelago, resulting in many endemic species. Furthermore, several of the island taxa belong to groups typically considered to be “poor dispersers” across sea barriers, which strongly supports a role for natural rafts in seeding the islands. Oceanic currents, including the freshwater pathways that extend from large river drainages into the Gulf of Guinea during the rainy season, also support this hypothesis. The distances between the islands are equivalent to those between the islands and the continent such that inter-island dispersal events appear to be relatively rare and thus few taxa are shared between them. Still, the islands present multiple cases of secondary contact leading to hybridization and genetic introgression between closely related lineages—providing several models to study the role and consequences of gene flow in evolution. Most taxa for which molecular estimates of divergence time have been derived are much younger than the ages of the islands. This pattern is consistent with high species turnover, likely resulting from a combination of small island sizes, proximity to the African continent and a long history of intense volcanic activity. The Gulf of Guinea oceanic islands provide multiple examples of classical adaptations to island life (the “island syndrome”), including giants and dwarves, ornament and color loss, among others. In addition, emerging studies of birds are highlighting the importance of competition regimes in driving phenotypic change—with examples of both character release (low inter-specific competition) and character displacement (inter-specific competition upon secondary contact). Collectively, the Gulf of Guinea oceanic islands offer unique opportunities to study adaptation and speciation in a range of taxa and contexts.

Shared ecological conditions encountered by species that colonize islands often lead to the evolution of convergent phenotypes, commonly referred to as “island syndrome”. Reduced immune functions have been previously proposed to be part of this syndrome, as a consequence of the reduced diversity of pathogens on island ecosystems. According to this hypothesis, immune genes are expected to exhibit genomic signatures of relaxed selection pressure in island species. In this study, we used comparative genomic methods to study immune genes in island species (N = 20) and their mainland relatives (N = 14). We gathered public data as well as generated new data on innate (TLR: Toll-Like Receptors, BD: Beta Defensins) and acquired immune genes (MHC: Major Histocompatibility Complex classes I and II), but also on hundreds of genes with various immune functions. As a control, we used a set of 97 genes, not known to be involved in immune functions based on the literature, to account for the increased drift effects of the lower effective population sizes in island species. We used synonymous and non-synonymous variants to estimate the selection pressure acting on immune genes. We found that BDs and TLRs have higher ratios of non-synonymous over synonymous polymorphisms (Pn/Ps) than randomly selected control genes, suggesting that they evolve under a different selection regime. However, simulations show that this is unlikely to be explained by ongoing positive selection or balancing selection. For the MHC genes, which evolve under balancing selection, we used simulations to estimate the impact of population size variation. We found a significant effect of drift on immune genes of island species leading to a reduction in genetic diversity and efficacy of selection. However, the intensity of relaxed selection was not significantly different from control genes, except for MHC class II genes. These genes exhibit a significantly higher level of non-synonymous loss of polymorphism than expected assuming only drift and evolution under frequency dependent selection, possibly due to a reduction of extracellular parasite communities on islands. Overall, our results showed that demographic effects lead to a decrease in the immune functions of island species, but the relaxed selection that is expected to be caused by a reduced parasite pressure may only occur in some categories of immune genes.

International audience; Oceanic islands share distinctive characteristics thought to underlie a set of parallel evolutionary trends across islands and taxonomic groupsincluding life history traits, morphology and visual signals. To which extent acoustic signals also change in parallel on islands is less clear. Some important processes associated with insularity, such as founder effects and reduced sexual selection, could lead to a decrease in vocal performance and song complexity on islands. In a field-based study, we recorded 11 insular species and their closest mainland relatives. Out of the 11 species pairs, 6 live in the tropics (São Tomé / Mount Cameroon), and 5 in the temperate region (Madeira / southern France). For each species we measured two proxies of vocal performance (song duration and syllable rate) and one proxy of song complexity (syllable diversity). This study did not recover a clear relationship between the island environment and song traits. If as expected, syllable rate was lower in island species than in their mainland counterparts, the two other proxies showed no clear island-mainland pattern of divergence. Several factors may explain the absence of reduction for song duration and syllable diversity. Among those, relaxation of interspecific competition on islands may have led to an increase in syllable diversity, or correlations between song variables may have constrained song evolution. More studies on island species are needed to draw a better picture of divergence patterns and go beyond the confounding ecological factors that could explain peculiar song characteristics in islands.

The archipelago of Sao Tome and Principe is a major centre of endemism for vertebrates but, to date, arthropods remain poorly studied, with the exception of mosquitoes due to their medical and economic relevance. Previous studies, over 20 years old, recorded 26 species of mosquitoes for Sao Tome and 14 for Principe, of which six and two were endemic to each island respectively. We collected mosquito larvae and adults on both islands and found three species as a first record, putting the number of mosquito species collected at least once on Sao Tome at 29 and 15 for Principe. We compared the mosquito richness on Sao Tome and Principe islands to 71 other oceanic islands represented within 20 archipelagoes worldwide. We used the general dynamic model of oceanic island biogeography and the associated ATT² (for Area+Time+Time²) model to explain two different metrics: (i) the richness of the single‐island endemics and (ii) the richness of archipelago endemics. We also included other island characteristics in our model, such as isolation and latitude. Our data compilation and comparative analyses revealed an overall low richness of endemic mosquitoes on islands, with the highest number of single‐island endemics found on Sao Tome Island. As predicted, we found a positive relationship between our two richness metrics and the general dynamic model ATT², although the model with the area (A) alone also explained endemic richness. Isolation was also predictor of mosquito diversification.

The Sao Tome Grosbeak Neospiza concolor, endemic to the island of Sao Tome (Gulf of Guinea), is one of the least known birds in the world. Formerly considered to be an aberrant weaver (Ploceidae), it is currently placed in a monotypic genus within the true finches (Fringillidae). Phylogenetic inference based on mitochondrial and nuclear sequences confidently identifies N. concolor as an Old World finch (Fringillidae: Carduelinae) within the Crithagra seedeater/canary clade. The Sao Tome Grosbeak is therefore the world's largest canary, 50% heavier than the next largest species, and it co-occurs with a population of its sister species, the Principe Seedeater Crithagra rufobrunnea.

SummaryNatural habitats are being rapidly lost due to human activities. It is therefore vital to understand how these activities influence biodiversity so that suitable guidelines can be established for conservation. This is particularly important in understudied, high biodiversity, areas such as the Angolan Escarpment. Here we examine which habitat characteristics drive bird diversity and endemic species presence at Kumbira Forest, a key site in the Central Escarpment Forest. Bird diversity was sampled by 10 min bird point counts, whereas habitat characteristics were measured by a combination of ground-based vegetation surveys and remotely sensed data modelling of Landsat images. GLM, multi-model inference and model averaging were used to determine the most important variables driving species richness and the presence of endemics. The remote sensing variables performed poorly in predicting presence of Red-crested Turaco Tauraco erythrolophus and Gabela Bushshrike Laniarius amboimensis but they contributed significantly to explain species richness and Gabela Akalat Sheppardia gabela presence, both of which were associated with greater canopy cover. Liana density and elevation were also important explanatory variables in certain cases. Conservation actions at Kumbira should focus on increasing canopy cover and maintaining forest integrity (as measured by liana density), as these actions are likely to have the most positive outcomes for the avifauna.

Angola has a rich history of ornithological exploration going back to the early 1800s. From the early-1970s to 2002, however, the civil war prevented access to many areas, and very little work on birds was done. From about the early 2000s information on birds in Angola has been gathered at an increasing rate, with new species being added to the list and a steady rise in publications on biogeography and biology of birds. With about 940 species, Angola has an impressive array of bird species, including c. 29 endemic species, and several species that are rare and poorly known. For the future, there are many areas of avian biology to attract studies, not only to gather more data on the rare and endemic species, but also local surveys of bird communities, the identification of major threats to the avifauna from landuse changes (concomitantly with suggestions for remedial action) and more. Understanding the role of birds in ecosystem processes, long term studies on the biology and breeding of individual species, and inferring the evolutionary history of the endemic species and of those species that occur in small isolated populations in Angola are all areas for future research. The future of ornithological research and conservation in Angola is dependent on it being carried out by Angolans – outreach, capacity building, and advanced training must all come together in order to find and train the motivated ornithologists that such a biodiversity-rich country deserves.

Rails (Aves: Rallidae) are renowned for their extreme dispersal capability, which has given rise to numerous island lineages. Many insular species lost the ability to fly as a response to release from predator pressure—a feature causing rapid extinction when humans subsequently introduced mammals. The world’s smallest extant flightless bird, the Inaccessible Island Rail Atlantisia rogersi, is endemic to Inaccessible Island, Tristan da Cunha archipelago, in the central South Atlantic Ocean. It is placed in a monotypic genus, but its taxonomic affinity, as well as geographic origin, are disputed. Contrary to its suggested Old World origin, we demonstrate that the Inaccessible Island Rail is nested within the mainly South American ‘Laterallus clade’ and that it colonized ≥3 million-year-old Inaccessible Island from South America c. 1.5 million years ago. The taxonomy of rails has traditionally been based on morphology, and convergent evolution has caused many cases of misclassification. We suggest a re-classification within the ‘Laterallus clade’ and call for extended coverage of taxon sampling for DNA sequencing.

The depletion of forests in conservation hotspots is a poorly known societal concern of the post‐conflict society of Angola. Rapid economic and population growth, fragile environmental regulation, enforcement, and planning threat these invaluable forests and their biodiversity. By mitigating climate change through a sustainable management of forests, Reducing Emissions from Deforestation and forest Degradation (REDD+) could also favour the preservation of biodiversity. This study addresses the depletion of forests in Angolan conservation ‘hotspots’ under a REDD+ perspective. In the escarpment forest, a centre of endemism, activity data, and emission factors were assessed between 2001 and 2014. Next, spatial factors associated with deforestation were identified using generalized linear modelling, and it was provided a view on how REDD+ may support sustainable forest management in conservation hotspots. Activity data based on an error‐corrected estimate indicated a deforested area of 4856.3 ± 653.1 ha between 2001 and 2014. Field mean above‐ground carbon content amounted to 89.4 ± 126.4 tCha‐1. Among the most relevant factors associated with deforestation were elevation, density of bare land, north–south exposure (aspect), and distance to trails. All negatively related to deforestation. Overall, the threatened escarpment forest conservation hotspot seems to have significant potential for reducing carbon emissions and beneficiate from REDD+. Yet the considerable uncertainty in our estimates limited the discussions in the magnitude of forest depletion and carbon emissions. In view of performance‐based payments for development, additional field surveying is necessary to boost the accuracies presented by new forest monitoring tools that can reduce technical difficulties and sustain the eligibility of Angola for international REDD+ funding sources.

SUMMARYThe coevolutionary relationships between avian malaria parasites and their hosts influence the host specificity, geographical distribution and pathogenicity of these parasites. However, to understand fine scale coevolutionary host–parasite relationships, robust and widespread sampling from closely related hosts is needed. We thus sought to explore the coevolutionary history of avianPlasmodiumand the widespread African sunbirds, family Nectariniidae. These birds are distributed throughout Africa and occupy a variety of habitats. Considering the role that habitat plays in influencing host-specificity and the role that host-specificity plays in coevolutionary relationships, African sunbirds provide an exceptional model system to study the processes that govern the distribution and diversity of avian malaria. Here we evaluated the coevolutionary histories using a multi-gene phylogeny for Nectariniidae and avianPlasmodiumfound in Nectariniidae. We then assessed the host–parasite biogeography and the structuring of parasite assemblages. We recoveredPlasmodiumlineages concurrently in East, West, South and Island regions of Africa. However, severalPlasmodiumlineages were recovered exclusively within one respective region, despite being found in widely distributed hosts. In addition, we inferred the biogeographic history of these parasites and provide evidence supporting a model of biotic diversification in avianPlasmodiumof African sunbirds.

Biological invasions have critical impacts on native biodiversity and human societies and especially on oceanic islands that are fragile and threatened ecosystems. The invasive tiger mosquito Aedes (Stegomyia) albopictus (Skuse, 1894) native to Southeast Asia has been introduced during the past 30 years almost everywhere in the world, including the Americas, the Pacific, Europe and Africa. It has been reported for the first time in the Gulf of Guinea in 2000, first in Cameroon, then in Bioko Island in 2003 and more recently in Gabon in 2007. Here we report the first record of Ae. albopictus on Sao Tome Island. Although we cannot estimate precisely the year of introduction on Sao Tome Island, it most likely arrived within the last 10 years. By sequencing the mitochondrial cytochrome c oxidase gene from individual adults, we detected three haplotypes already present in mainland Africa. More studies are needed to explore the dynamics of its expansion and competition with insular native mosquitoes.

Aim Lower species diversity, increased population densities and ecological niche enlargement are common characteristics of island faunas. However, it remains to be determined if they extend to the parasite community. We tested if Haemosporidia parasite pressure varies between islands and the mainland with two different levels of analysis: (1) at the host community level and (2) with paired-species comparisons between islands and the mainland. Location Gulf of Guinea, West Africa. Methods We used molecular-based methods to identify avian Haemosporidian parasites (Plasmodium, Haemoproteus and Leucocytozoon) to describe their diversity, prevalence, host specificity and their phylogenetic relationships in five islands of the Gulf of Guinea and in nearby mainland areas. Results We found reduced Haemosporidia diversity on islands for Haemoproteus and Leucocytozoon, but not for Plasmodium. In addition, lower parasite prevalence on islands was found using a paired-species approach. Although the mean host specificity of the parasite community on islands did not differ from the mainland, we found a very distinct parasite species assemblage on the islands, which was composed of both the most generalist and the most specialist lineages. Main conclusions This study supports the hypothesis that parasite pressure is reduced on islands. Colonization is made by generalists with high host switching capacities, with some subsequently evolving into highly specialized parasites. This suggests that “taxon cycle” dynamics may explain the assemblage of insular parasite communities.

Kumbira Forest is the best representative area of Angola's Central Escarpment and the only site known to hold significant populations of four of the five threatened endemic bird species of this habitat. However, the forest is disappearing as a result of human activities. Remote-sensing techniques were used to assess changes in forest cover, and bird and habitat surveys were performed to assess the effect of land-use changes on endemic species and the bird community. No relationships could be established between the presence of endemics and habitat and landscape variables. This lack of effect may be attributable to the low number of records and compounded by the mosaic structure of the landscape. Although forest cover has been maintained in Kumbira, old-growth forest has been replaced by secondary growth in many areas. Nevertheless these secondary-growth forest patches can maintain a bird community similar to that found in old-growth forest.

The role of natural selection in promoting reproductive isolation has received substantial renewed interest within the last two decades. As a consequence, the study of ecological speciation has become an extremely productive research area in modern evolutionary biology. Recent innovations in sequencing technologies offer an unprecedented opportunity to study the mechanisms involved in ecological speciation. Genome scans provide significant insights but have some important limitations; efforts are needed to integrate them with other approaches to make full use of the sequencing data deluge. An international conference 'Advances in Ecological Speciation' organized by the University of Porto (Portugal) aimed to review current progress in ecological speciation. Using some of the examples presented at the conference, we highlight the benefits of integrating ecological and genomic data and discuss different mechanisms of parallel evolution. Finally, future avenues of research are suggested to advance our knowledge concerning the role of natural selection in the establishment of reproductive isolation during ecological speciation. © 2013 John Wiley & Sons Ltd., The AES conference was organized within the framework of a research project (FCOMP-01-0124-FEDER-014272, PTDC/BIA-EVF/113805/2009) financed by FEDER through COMPETE and by Portuguese national funds through FCT (Fundação para a Ciência e a Tecnologia). This meeting was part of the European Science Foundation's Research Networking Programme ‘Frontiers of Speciation Research’ (FroSpects, www.iiasa.ac.at/Research/EEP/FroSpects) and was cosponsored by the REGPOT-CT-2011-286431-CIBIO-NEW-GEN (PI: Nuno Ferrand) within the framework of the program SP4 – Capacities, Coordination and Support Action from the European Commission (EU FP7) and by the University of Porto. RF, CP, JMF and MM are financed by FCT under the Programa Operacional Potencial Humano – Quadro de Referência Estratégico Nacional from the European Social Fund and the Portuguese Ministério da Educação e Ciência through postdoctoral fellowships (SFRH/BPD/26384/2006 and SFRH/BPD/89313/2012, SFRH/BPD/28869/2006, SFRH/BPD/43264/2008 and SFRH/BPD/46407/2008, respectively). JG is currently supported by an ‘Isidro Parga Pondal’ fellowship (Xunta de Galicia). RKB is supported by NERC and by the Swedish Research Council.

We present what is known about the Gulf of Guinea band-rumped storm petrels Hydrobates cf. castro to identify priority areas for research and conservation. Addressed are: occurrence in the Gulf of Guinea, including museum specimens, at-sea records, observations on the islands, and potential breeding sites; seasonality, the timing of breeding inferred from condition of trapped birds and birds at sea in primary moult; morphology, including biometrics, structure, plumage aspect; aerial vocalisations at the suspected breeding grounds; and taxonomy. The first photographs and sonograms pertaining to this population to be published are also presented. The evidence indicates that this storm petrel is present in the Gulf of Guinea year-round. It almost certainly breeds on Sao Tome during both the wet and long dry seasons, and breeding is probably protracted, possibly seasonal. Morphology indicates a degree of distinctiveness and aerial vocalisations suggest possible taxonomic affinities with Cape Verde Storm Petrel H. jabejabe. Our observations are provisional and further research is required. The three most pressing matters for future research are clarifying taxonomy, locating breeding colonies and identifying key threats.

SummaryAfromontane forest is the most localised and threatened habitat type in Angola. For the past 40 years the estimate of the area covered by this habitat in Angola has been c.200 ha. At present, 85 ha remain at Mt Moco, the most important known site to date. This habitat holds 20 bird taxa of conservation significance but some are now rare or absent at Mt Moco. Given the small extent of forest, its high conservation value and the severe human impacts on it, finding new areas of Afromontane forest is a high conservation priority. With this objective, we visited the Namba mountains in July 2010, where c.100 ha was thought to remain in the 1970s, to establish the extent and condition of forest there and to conduct bird surveys. We found closed-canopy Afromontane forest with an abundance of Podocarpus latifolius and little human disturbance. We recorded 89 bird species, 56 in or adjacent to forest and including all 20 priority taxa and a significant population of the Endangered Swierstra’s Francolin Pternistis swierstrai. On-screen digitising of forest patches using Google Earth indicates that the larger patches are an order of magnitude larger than at Mt Moco and that there is currently > 590 ha of forest in the Namba mountains, more than trebling the previous national estimate. The site qualifies as a new Important Bird Area and is a high priority for inclusion in Angola’s protected area network.

). A unica estimativa previa de 498‐996 individuos adultos baseou-se numa estimativa incorrecta da area de ocorrencia. Apesar de ser mais abundante do que se estimava, esta especie ainda preenche os criterios para a categoria ‘Em Perigo’ devido a sua distribuicao restrita. E provavel que a sua area de distribuicao seja maior, mas recomendamos que se mantenha a classificacao ‘Em Perigo’ ate que sejam obtidos dados que comprovem esta suposicao. Esta especie nao existe em nenhuma area protegida, mas parece tolerar alguma perturbacao visto mostrar preferencia por floresta secundaria e bordas de floresta a 600‐870 m de altitude. Finalmente, descrevemos em detalhe as vocalizacoes desta especie e discutimos a literatura sobre a sua posicao sistematica. Summary: The Endangered Braun’s Bushshrike Laniarius brauni is restricted to an area of less than 5,000 km 2 in northern Angola. We review previous literature on this species, summarise information on specimens and provide details of our own unpublished records. From this we calculate a range size of 3,500 km 2 and, based on the assumption of a mean density of 1‐2 individuals/km 2 , calculate a population size of 3,500‐7,000 mature individuals. The only previous population size of 498‐996 individuals was based on an erroneous range size. Despite being more numerous than previously estimated, and potentially more widespread, it still meets criteria for Endangered status based on range size. We recommend that it retains Endangered status pending the collection of further field data. The species does not occur in any conservation area, although it is perhaps tolerant of some habitat disturbance, favouring secondary forest and forest edge at 600‐870 m. Finally, we describe in greater detail its vocalisations and discuss its systematic treatment in the literature.

Archipelago-endemic bird radiations are familiar to evolutionary biologists as key illustrations of evolutionary patterns. However, such radiations are in fact rare events. White-eyes (Zosteropidae) are birds with an exceptionally high colonization and speciation potential; they have colonized more islands globally than any other passerine group and include the most species-rich bird genus. The multiplication of white-eye island endemics has been consistently attributed to independent colonizations from the mainland; the white-eyes of the Gulf of Guinea archipelago had been seen as a classic case, spanning as great a breadth of phenotypic diversity as the family worldwide. Contrary to this hypothesis, our molecular phylogenetic analysis places the Gulf of Guinea white-eyes in just two radiations, one grouping all five oceanic island taxa and the other grouping continental island and land-bridge taxa. Numerous ‘aberrant’ phenotypes (traditionally grouped in the genus Speirops) have evolved independently over a short space of time from nonaberrant (Zosterops) phenotypes; the most phenotypically divergent species have separated as recently as 0.22 Ma. These radiations rival those of Darwin’s finches and the Hawaiian honeycreepers in terms of the extent of adaptive radiation per unit time, both in terms of species numbers and in terms of phenotypic diversity. Tempo and patterns of morphological divergence are strongly supportive of an adaptive radiation in the oceanic islands driven by ecological interactions between sympatric white-eyes. Here, very rapid phenotypic evolution mainly affected taxa derived from the youngest wave of colonization, in accordance with the model of asymmetric divergence owing to resource competition in sympatry.

SummaryThe forests of the Angolan highlands are the smallest and most isolated of the Afromontane centres of endemism. Despite their high biodiversity value and small, fragmented extent of less than 200 ha, they remain entirely unprotected. Here we draw attention to their uniqueness and the threats to their conservation. We specifically highlight the importance of Mt Moco to bird conservation and describe current forest cover and condition. Sixty-four endemic/near-endemic species/subspecies and taxa with isolated populations are associated with the highlands of western Angola. All 19 forest-dependent taxa are among the 233 species recorded at Mt Moco, which include a rich diversity of montane specialists. Swierstra’s Francolin Pternistis swierstrai is the only threatened endemic. In 2009, 10 of 30 forest patches at Mt Moco larger than 0.5 ha were surveyed for this species. It occurred in seven of these surveyed patches, at a mean minimum density of 0.95 pair ha−1 in forest patches > 1 ha. Based on extrapolations of this figure, we estimate a minimum of 75 pairs of Swierstra’s Francolin at Mt Moco, and 185–420 pairs worldwide. Due to both limited range and small population size, we propose the species be up-listed from ‘Vulnerable’ to ‘Endangered’. Total forest cover at Mount Moco in forest patches > 0.5 ha in size is currently 85 ha. This is c.40% of the total cover of Afromontane forest estimated for Angola in 1974. Remaining forest cover at Mt Moco is being eroded by bush fires, removal of wood for fire and construction material, and clearance for subsistence agriculture by the c.330 inhabitants of Kanjonde village. In order to preserve the forest of Mt Moco, we propose the implementation of a protected area and define its boundaries. A similar proposal was made in 1974 for the creation of the Mount Moco Special Reserve.

SummaryRecently recognised as specifically distinct, the Príncipe Thrush Turdus xanthorhynchus is endemic to the island of Príncipe in the Gulf of Guinea, West Africa. Formerly treated as conspecific with the more abundant T. olivaceofuscus from the nearby island of São Tomé, the Príncipe Thrush is considered rare and likely to be restricted to primary rainforest. A 2007 survey of Príncipe comprising 177 point transect locations covering 13 sites under different land uses (six in primary forest, three in secondary forest and four in plantations) encountered 18 individuals. Thrushes were found only in primary rainforest, where overall densities were 0.10 birds ha−1, equating to a population size of 435 individuals (95% confidence intervals: 208–913). We adjusted this estimate to take into account the fact that the highest density (0.22 birds ha−1) only occurred above 600 m, giving a final estimated population size of only 364 birds (95% confidence intervals: 186–887). In light of evidence of recent declines, possibly driven by hunting pressure, in the number of mature individuals and the limited area of occurrence of the species, the IUCN Red List category for the Príncipe Thrush should be ‘Critically Endangered’ under both criteria B1a+b(iii and v) and C2a(ii). The recent designation of the primary forests of southern Príncipe as a protected area (Parque Natural d’Obô do Príncipe) provides an opportunity for the conservation of this newly described species, which we recommend is used as a flagship for the forests as a whole.

Terrestrial and freshwater molluscs are amongst the most threatened of all taxa, yet data exist on the distribution and status of only a small proportion of the species. Here we present the results of the first systematic survey of a terrestrial mollusc on the island of Príncipe in the Gulf of Guinea. Archachatina bicarinata has never been previously surveyed, despite being categorized as Vulnerable on the IUCN Red List and suffering from unregulated harvesting for food. We found that A. bicarinata is restricted to primary rainforest and its abundance and probability of occurrence increased as surveyed sites became less accessible. Additional anecdotal evidence from the observations of previous scientific expeditions, local guides and snail harvesters suggested that the species has suffered a dramatic decline in population size and distribution in recent years. We therefore recommend that immediate action be taken to prevent its imminent extinction on Príncipe. The collection of A. bicarinata from protected areas should be banned, as should commercial harvesting and sales. Subsistence collecting should be limited to larger individuals. Our data have been used to inform the management plans for the protected areas on Príncipe and São Tomé, and this should help to ensure the future of A. bicarinata on both islands.

A Gulf of Guinea island endemic is a member of a Mediterranean-centred bird genus GARY VOELKER,* MARTIM MELO & RAURI C. K. BOWIE Department of Wildlife and Fisheries Sciences and Texas Cooperative Wildlife Collections, Texas A&M University, College Station, TX 77843, USA Percy FitzPatrick Institute, DST ⁄NRF Centre of Excellence, University of Cape Town, Rondebosch 7701, South Africa Museum of Vertebrate Zoology and Department of Integrative Biology, 3101Valley Life Science Building, University of California, Berkeley, CA 94720, USA

Phylogenetic relationships of the Gulf of Guinea Alcedo kingfishers MARTIM MELO 1 * & JEROME FUCHS 2 † 1 Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, King’s Buildings, West Mains Road, Edinburgh EH9 3 JT, UK 2 UMR 5202 ‘Origine Structure et Evolution de la Biodiversite’, Departement Systematique et Evolution, and Service Commun de Systematique Moleculaire, IFR CNRS 101, Museum National d’Histoire Naturelle, Case postale 51, 55 Rue Buffon, 75005 Paris, France

The range of the grey parrot (Psittacus erithacus), one of the most heavily harvested bird species for the international pet trade, spans the forest belt of Central and West Africa and includes the oceanic island of Principe (Gulf of Guinea). Morphological variation led to the recognition of two mainland subspecies (P. e. erithacus and P. e. timneh). The population from Principe was originally described as a separate species (P. princeps) but is currently included in the nominate race. We used 1932 bp of the mitochondrial genome to clarify the genealogical affinities between the two currently-recognized mainland subspecies and the Principe population. Sampling included 20 individuals from Principe, 17 from P. e. erithacus, and 13 from P. e. timneh. We found that the two mainland subspecies form two independent lineages, having diverged up to 2.4 million years ago (Ma), and that the Principe population is composed of two lineages that diverged in allopatry. The most common lineage is descended from the first colonizers and evolved in isolation for up to 1.4 Ma. Contrary to current understanding, this 'Principe lineage' is more closely related to the timneh than to the erithacus subspecies. The second lineage consists of P. e. erithacus birds from the nearby mainland that colonized the island in recent times. The evolutionary dynamics of the grey parrot population of Principe are primarily characterized by isolation, with new genetic variation being added through rare immigration events. The heavily harvested Principe grey parrot population should therefore be treated as an independent conservation unit.

Aim Amphibians are a model group for studies of the biogeographical origins of salt-intolerant taxa on oceanic islands. We used the Gulf of Guinea islands to explore the biogeographical origins of island endemism of one species of frog, and used this to gain insights into potential colonization mechanisms. Location Sao Tome and Principe, two of the four major islands in the Gulf of Guinea, West Africa, are truly oceanic and have an exceptionally high biodiversity. Methods Mitochondrial DNA is used to test the endemic status of a frog from Sao Tome and compare it with congeneric taxa from tropical Africa. Existing data on surface currents, surface salinity, atmospheric circulation and bird migration in the Gulf of Guinea are summarized to address hypotheses concerning colonization mechanisms. Results The endemic status of Ptychadena newtoni (Bocage) is supported here by mitochondrial DNA sequences, and analysis of this and other molecular data indicates that an East African species close to Ptychadena mascareniensis (Dumeril and Bibron) is its nearest relative. We refute the possibility that this population was anthropogenically introduced, in favour of a natural dispersal mechanism. Main conclusions With six endemic frogs and one caecilian, the Gulf of Guinea islands harbour a diverse amphibian fauna. Five of these species appear to have their closest relatives in East Africa. Insufficient evidence exists for transportation by storms, birds or rafts alone. However, we propose a synergy of rafting, favourable surface currents and a reduction in salinity of surface waters. Catastrophic events, or wet periods in climatic history, could allow freshwater paths to open far enough to enable continental flora and fauna to reach these and other isolated oceanic islands.

We tested 74 passerine microsatellite loci for cross-amplification in the Principe seedeater (Serinus rufobrunneus), and identified 15 loci that were both polymorphic and easy to score. In a sample of 113 individuals, the number of alleles ranged between three and 71. Three loci deviated from Hardy-Weinberg equilibrium after correcting for multiple tests, and one locus had high estimated null allele frequency. These 15 loci were highly successful in amplifying polymorphic products also in nine other Serinus species.

The introduction of avian malaria ( Plasmodium relictum ) to Hawaii has provided a model system for studying the influence of exotic disease on naive host populations. Little is known, however, about the origin or the genetic variation of Hawaii's malaria and traditional classification methods have confounded attempts to place the parasite within a global ecological and evolutionary context. Using fragments of the parasite mitochondrial gene cytochrome b and the nuclear gene dihydrofolate reductase-thymidylate synthase obtained from a global survey of greater than 13 000 avian samples, we show that Hawaii's avian malaria, which can cause high mortality and is a major limiting factor for many species of native passerines, represents just one of the numerous lineages composing the morphological parasite species. The single parasite lineage detected in Hawaii exhibits a broad host distribution worldwide and is dominant on several other remote oceanic islands, including Bermuda and Moorea, French Polynesia. The rarity of this lineage in the continental New World and the restriction of closely related lineages to the Old World suggest limitations to the transmission of reproductively isolated parasite groups within the morphological species.