Abundance and prey capture success of Common Terns (Sterna hirundo) and Pied Kingfishers (Ceryle rudis) in relation to water clarity in south-east coastal Ghana

Abstract Background Water clarity may negatively influence rate of plunge diving and prey capture success of piscivorous plunge-diving birds, and therefore has implications for their conservation in polluted urban wetlands. We studied the relationship between water clarity and the abundance and prey capture success of Pied Kingfishers (Ceryle rudis) and Common Terns (Sterna hirundo) in two polluted coastal waters of south-east Ghana—the Weija Lake and Densu Delta Ramsar Site. Methods On each wetland, data on abundance and prey capture success of plunge-divers were collected in four spatio-temporal quadrats of 100 m × 100 m and analysed with concurrent measurements of water quality parameters using GLM regression with Pearson’s correlation coefficients. Results Mean prey capture success of Pied Kingfishers (34.7 ± 13.1%) and Common Terns (35.3 ± 11.0%) were similar but the two species responded differently to water clarity. The abundance of Common Terns was significantly higher in less transparent/more turbid water while that of Pied Kingfishers showed no significant relationship with turbidity and transparency. In contrast, the prey capture success of Common Terns was neither related to transparency nor turbidity, as opposed to that of Pied Kingfishers which was significantly higher in more turbid/less transparent waters. Correlations between capture success and bird abundance, as well as capture attempts were insignificant, suggesting that increased fish abundance associated with cloudy water may not necessarily promote higher abundance and capture success of foraging birds. Thus, when foraging in less transparent water, capture success may depend more on predator avoidance by fish prey than lower prey detectability of foraging birds. Conclusion Within a gradient of 15–51 cm transparency studied, lower water clarity did not constrain prey capture success of Common Terns and Pied Kingfishers. Further studies on the foraging ecology of plunge-divers in coastal Ghana are however required to make firm conclusions on the relationship between water clarity and foraging birds and fish prey abundances, as well as capture success

Epidemiology, ecology and human perceptions of snakebites in a savanna community of northern Ghana.

BackgroundWorldwide, snakebite envenomations total ~2.7 million reported cases annually with ~100,000 fatalities. Since 2009, snakebite envenomation has intermittently been classified as a very important 'neglected tropical disease' by the World Health Organisation. Despite this emerging awareness, limited efforts have been geared towards addressing the serious public health implications of snakebites, particularly in sub-Saharan Africa, where baseline epidemiological and ecological data remain incomplete. Due to poverty as well as limited infrastructure and public health facilities, people in rural Africa, including Ghana, often have no other choice than to seek treatment from traditional medical practitioners (TMPs). The African 'snakebite crisis' is highlighted here using regionally representative complementary data from a community-based epidemiological and ecological study in the savanna zone of northern Ghana.Methodology and findingsOur baseline study involved two data collection methods in the Savelugu-Nanton District (in 2019 the district was separated into Savelugu and Nanton districts) in northern Ghana, comprising a cross-sectional study of 1,000 residents and 24 TMPs between December 2008 and May 2009. Semi-structured interviews, as well as collection of retrospective snakebite and concurrent rainfall records from the Savelugu-Nanton District Hospital and Ghana Meteorological Authority respectively over 10-years (1999-2008) were used in the study. Variables tested included demography, human activity patterns, seasonality, snake ecology and clinical reports. Complementary data showed higher snakebite prevalence during the rainy season, and a hump-shaped correlation between rainfall intensity and snakebite incidences. Almost 6% of respondents had experienced a personal snakebite, whereas ~60% of respondents had witnessed a total of 799 snakebite cases. Out of a total of 857 reported snakebite cases, 24 (~2.8%) died. The highest snakebite prevalence was recorded for males in the age group 15-44 years during farming activities, with most bites occurring in the leg/foot region. The highest snakebite rate was within farmlands, most severe bites frequently caused by the Carpet viper (Echis ocellatus).ConclusionThe relatively high community-based prevalence of ~6%, and case fatality ratio of ~3%, indicate that snakebites represent an important public health risk in northern Ghana. Based on the high number of respondents and long recording period, we believe these data truly reflect the general situation in the rural northern savanna zone of Ghana and West Africa at large. We recommend increased efforts from both local and international health authorities to address the current snakebite health crisis generally compromising livelihoods and productivity of rural farming communities in West Africa

A conservation assessment of the herpetofauna of a moist semi- deciduous forest in Ghana

Abstract A conservation assessment of amphibians and reptiles was undertaken in the Gyemera Forest Reserve (GFR) and Gyeni River Forest Reserve (GRFR) in the Moist Semi-deciduous forests of the Amansie West District of the Ashanti Region of Ghana. Refuge examination, acoustic searches, pitfall trapping and interviews were employed in data collection at the study sites. Forty herpetofaunal species were recorded comprising 16 amphibians (two toads and 14 frogs) and 24 reptiles (one chelonian, 14 lizards and nine snakes). Four species (one lizard and three snakes) were not directly encountered but were recorded from interviews of local residents. The GRFR recorded a higher number of species than GFR and there was a low similarity in species composition between the sites (Sorenson's Similarity Index CS = 0.52). Five species were widely distributed and frequently encountered and only 12 species were directly recorded within the forest reserves. The main threats to herpetofaunal species in the study area were habitat destruction and fragmentation due to illegal logging and small-scale/artisanal mining. Four species were of conservation concern; Phrynobatrachus alleni is listed as Near Threatened by the IUCN and the other three; Kinixys erosa, Varanus niloticus and Python sebae are listed in CITES Appendix II where limited trading is allowed and are nationally protected. Inclusion of the local people in conversation initiatives as well as conservation education and awareness programmes would help sensitise and concientise them about the need to conserve biodiversity. Also, enforcement of the laws on illegal logging and mining should be intensified

Data from: Genetic and paleomodelling evidence of the population expansion of the cattle egret Bubulcus ibis in Africa during the climatic oscillations of the Late Pleistocene

Increasing aridity during glacial periods produced the retraction of forests and the expansion of arid and semi-arid environments in Africa, with consequences for birds. Cattle egret (Bubulcus ibis) is a dispersive species that prefers semiarid environments and requires proximity to bodies of water. We expected that climatic oscillations led to the expansion of the range of the cattle egret during arid periods, such as the Last Maximum Glacial (LGM) and contraction of distribution during the Last Interglacial (LIG) period, resulting in contact of populations previously isolated. We investigated this hypothesis by evaluating the genetic structure and population history of 15 cattle egret breeding colonies located in West and South Africa using the mitochondrial DNA (mtDNA) control region, mtDNA ATPase 8 and 6, and an intron of nuclear gene transforming growth factor beta-2. Occurrence data and bioclimatic information were used to generate ecological niche models of three periods (present, LGM and LIG). We used the genetic and paleomodelling data to assess the responses of the cattle egret from Africa to the climatic oscillations during the late Pleistocene. Genetic data revealed low levels of genetic differentiation, signs of isolation-by-distance, as well as recent increases in effective population size that started during the LGM. The observed low genetic structure may be explained by recent colonization events due to the demographic expansion following the last glacial period and by dispersal capacity of this species. The paleomodels corroborated the expansion during the LGM, and a more restricted potential distribution during the LIG. Our findinds supports the hypothesis that the species range of the cattle egret expanded during arid periods and contracted during wet periods

Nexus file of DNA sequence alignments for ATPase 6 and 8

Nexus file of DNA sequence alignments for ATPase 6 and

Nexus file of DNA sequence alignments for phased alleles of the intron 5 of the TGFB2

Nexus file of DNA sequence alignments for phased alleles of the intron 5 of the TGFB

Nexus file of DNA sequence alignments for mtDNA control region without nine positions with signs of homoplasy

Nexus file of DNA sequence alignments for mtDNA control region without nine positions with signs of homoplas