Browsing by Author "Holbech, L.H."
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Item 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(Avian Research, 2018-12) Holbech, L.H.; Gbogbo, F.; Aikins, T.K.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 turbid-ity 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, suggest-ing 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.Item Distribution and abundance of small mammals in different habitat types in the Owabi Wildlife Sanctuary, Ghana.(Journal of Ecology and the Natural Environment, 5 (5): 83-87, 2013) Garshong, R.A.; Attuquayefio, D.K.; Holbech, L.H.; Adomako, J.K.Information on the small mammal communities of the Owabi Wildlife Sanctuary is virtually non-existent despite their role in forest ecosystems. A total of 1,500 trap-nights yielded 121 individuals of rodents and shrews, comprising five species: Praomys tullbergi, Lophuromys sikapusi, Hybomys trivirgatus, Malacomys edwardsi and Crocidura buettikoferi, captured in Sherman traps using 20 × 20 m grids. P. tullbergi was the most common small mammal species in all the four habitat types surveyed, comprising 63.6% of the total number of individual small mammals captured. The Cassia-Triplochiton forest had 61.2% of the entire small mammal individuals captured, and was the only habitat type that harboured higher abundances of the rare small mammal species in the sanctuary (H. trivirgatus and M. edwardsi). It also showed dissimilarity in small mammal species richness and abundance by recording a Sǿrenson’s similarity index of less than half in comparison with the other three habitat types. Management strategies for the sanctuary should therefore be structured to have minimal impact in terms of development and encroachment on the Cassia-Triplochiton forest area in order to conserve the rare species and biodiversity of the Owabi Wildlife Sanctuary.Item Epidemiology, ecology and human perceptions of snakebites in a savanna community of northern Ghana(PLoS Neglected Tropical Diseases, 2019-06-25) Musah, Y.; Ameade, E.P.K.; Attuquayefio, D.K.; Holbech, L.H.Worldwide, 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 findings Our 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). Conclusion The 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.Item Lack of conservation effort rapidly increases african great ape extinction risk(Conservation Letters, 2012-01) Tranquilli, S.; Abedi-Lartey, M.; Amsini, F.; Arranz, L.; Asamoah, A.; Babafemi, O.; Barakabuye, N.; Campbell, G.; Chancellor, R.; Davenport, T.R.B.; Dunn, A.; Dupain, J.; Ellis, C.; Etoga, G.; Furuichi, T.; Gatti, S.; Ghiurghi, A.; Greengrass, E.; Hashimoto, C.; Hart, J.; Herbinger, I.; Hicks, T.C.; Holbech, L.H.; Huijbregts, B.; Imong, I.; Kumpel, N.; Maisels, F.; Marshall, P.; Nixon, S.; Normand, E.; Nziguyimpa, L.; Nzooh-Dogmo, Z.; Okon, D.T.; Plumptre, A.; Rundus, A.; Sunderland-Groves, J.; Todd, A.; Warren, Y.; Mundry, R.; Boesch, C.; Kuehl, H.A network of resource management areas (RMAs) exists across tropical Africa to protect natural resources. However, many are poorly managed and weakly protected. We evaluated how the lack of conservation effort influences the extinction risk of African great apes. We compiled information on presence/ absence of primary (law enforcement guards) and secondary (tourism, research) conservation activities and nongovernmental conservation organizations (NGOs) support for 109 RMAs over the last 20 years. Along with these data, we collected environmental and anthropogenic variables, including recent records of ape presence/absence for all RMAs. As expected, law enforcement as a primary activity was the best predictor of ape survival rather than tourism or research as secondary activities. Furthermore, long-term NGO support had a significant positive influence on ape persistence. Our study demonstrates the feasibility of evaluating the relative importance of different conservation activities, an important step towards more evidence-based approaches in ape conservation. © 2011 Wiley Periodicals, Inc.Item Mitochondrial DNA density of peripheral white blood cells as a possible bio-marker of migratory status in partially migrating bird populations(Ecology, Environment and Conservation, 2013-01) Ocloo, A.; Holbech, L.H.; Gbogbo, F.With the novelty of bird banding, radar studies, satellite tracking and systematic field observations, major advances have been made in understanding the complexity of bird migration. However, in the quest to determine the migratory status of individuals in partially migrating bird populations, most of these methods come with major disadvantages. Given that the proportion of migrants and non-migrants in partial migration populations could indicate trends in the success of the migratory process and the selection pressure on migratory bird populations, the need for research into identifying an affordable and direct method of determining the migratory status of partial migrants cannot be overemphasized. This paper generates a new platform for research into Distinguishing individuals in a partially migratory populations based on acquired differences in mitochondrial biogenesis. The complexity of this kind of research and the variety of skills required for its execution, calls for the promotion of the idea. Copyright © EM International.Item Ophidiophobia, myth generation, and human perceptions: Implications for snake conservation in a typical savanna community of northern Ghana(Taylor & Francis Group, 2021) Musah, Y.; Attuquayefio, D.K.; Pobee, A.N.A.; Holbech, L.H.Snakes have fascinated and terrified humans throughout history. Worldwide, innate fear (ophidiophobia), culturally-founded superstition, and myths have caused pervasive snake persecution, snakebite mismanagement, human injuries, and fatalities, particularly in the tropics. We analyzed 20 common snake myths narrated by 934 respondents inhabiting a typical rural savanna community of northern Ghana. The myths summarized perceived, self-assessed knowledge about snakes and were evaluated in their zoo-ecological contexts versus their folkloristic explanatory origins. Only eight snake myths (~40%) had any justifiable scientific basis, partially representing misinterpretations among predominantly male, less-educated respondents. Contrastingly, 70% of the myths were largely rooted in ophidiophobia, representing a major driver of human-wildlife conflict and indiscriminate snake persecution. To promote wildlife-friendly perceptions and behavior toward snakes and their conservation, we recommend innovative gap-bridging conservation education and public awareness that reconciles myths and realities about snakes, thus reducing snakebite incidences, mortality, and widespread persecution and killing of snakes.Item A rapid assessment of species-specific bird strike risk at the Kotoka International Airport in Accra, Ghana(Ostrich, 2015-09) Holbech, L.H.; Asamoah, A.; Owusu, E.H.The Kotoka International Airport in Accra, the capital city of Ghana, has in recent years been confronted with increased presence of birds posing great challenges to aviation safety due to a high risk of bird strikes. As part of measures to mitigate the negative impacts of increasing numbers of birds, a species-specific bird strike risk index (SSBR) was modelled and calculated for a total of 86 species recorded within and near the airport. Based on the SSBR index, four species were classified as ‘critical risk’ and another four species as ‘high risk’. All six species, namely Corvus albus, Necrosyrtes monachus, Milvus migrans parasitus, Bubulcus ibis, Falco biarmicus and Falco tinnunculus, constituting 7% of the total species assemblage, were considered ‘problem species’. During the intensive, albeit short, study period, we also recorded bird strikes of N. monachus, F. biarmicus and notably M. m. parasitus. We conclude that wildlife management to avert the risk of bird strikes could be successfully achieved by adopting both proactive and reactive measures to reduce the presence of problem species at the aerodrome. © 2015 NISC (Pty) Ltd.Item Research and conservation of the larger parrots of Africa and Madagascar: a review of knowledge gaps and opportunities(Ostrich, 2014-12) Martin, R.O.; Perrin, M.R.; Boyes, R.S.; Abebe, Y.D.; Annorbah, N.D.; Asamoah, A.; Bizimana, D.; Bobo, K.S.; Bunbury, N.; Brouwer, J.; Diop, M.S.; Ewnetu, M.; Fotso, R.C.; Garteh, J.; Hall, P.; Holbech, L.H.; Madindou, I.R.; Maisels, F.; Mokoko, J.; Mulwa, R.; Reuleaux, A.; Symes, C.; Tamungang, S.; Taylor, S.; Valle, S.; Waltert, M.; Wondafrash, M.Parrot populations in Africa and Madagascar are declining and the need for conservation actions to address threats is increasingly recognised. Effective conservation requires a robust knowledge base on which decisions over appropriate actions can be made, yet at present there is no current and readily accessible synthesis of the status of populations, the threats they face and knowledge gaps. Here we begin to address this shortfall for the larger species in the region belonging to the genera Coracopsis, Poicephalus, Psittacus and Psittacula. We review developments since the production of the IUCN Parrot Action Plan published in 2000, identify areas where critical knowledge is lacking and highlight opportunities to address them. While advances have been made over the last decade, progress has not been evenly spread, with a strong bias towards populations in southern Africa. To date much research has focused on describing aspects of ecology and behaviour and there remains a need for studies determining the current status of populations and the factors limiting distributions and abundance. This review aims to provide a basis upon which progress towards an improved understanding of the conservation needs of the larger parrots of Africa and Madagascar can be made. © 2014, NISC (Pty) Ltd.Item Severe declines of understory birds follow illegal logging in Upper Guinea forests of Ghana, West Africa(Biological Conservation, 2015-08) Arcilla, N.; Holbech, L.H.; O'Donnell, S.We investigated how legal logging history and recent illegal logging affected forest bird community structure in Ghana. Ghanaian forests belong to West Africa’s highly fragmented Upper Guinea rain forests, part of a global priority “biodiversity hotspot” under intense pressure from anthropogenic degradation. Between 1995 and 2010, officially-reported legal logging intensities increased up to ∼600%, while illegal logging, which now accounts for 80% of timber extraction in Ghana, has driven logging intensities to ∼6 times greater than the maximum sustainable rate. We collected data in 2008–2010 and used a comparable dataset collected in 1993–1995 to assess impacts of recent logging on understory bird communities in large forest fragments (100–524 km2) in southwest Ghana. Forest understory bird species abundance declined by >50% during this period. Species richness also showed declining trends. Whereas analysis based on data collected in 1993–1995 estimated a partial post-logging recovery of the understory bird community at that time, data from 2008–2010 showed no indication of post-logging recovery, likely due to ongoing illegal logging following intensive legal logging operations. Forest generalist species and sallying insectivores declined significantly in logged compared to unlogged forests. These severe declines of Upper Guinea forest understory birds indicate the rapidly deteriorating conservation status of a biodiversity hotspot and could signal collapsing ecosystem processes. Immediate conservation actions are urgently required to protect surviving forest fragments from further degradation and avian declines.Item Uncontrolled hunting and habitat degradation decimate and extirpate forest hornbills in Ghana, West Africa(Elsevier Ltd, 2018) Holbech, L.H.; Annorbah, N.N.D.; Phalan, B.; Arcilla, N.Tropical forests are on the front lines of the current global extinction crisis. Species with restricted habitat requirements and slow reproductive rates, such as the spectacular hornbills (Bucerotidae) of the Paleotropics, are particularly vulnerable. We present the first long-term quantitative population assessment of nine forest hornbill species in Ghana, part of the Upper Guinea forest biodiversity hotspot in West Africa. From 1990 to 2009, hornbill encounter rates declined with 32–88% across eight species found in the region. Seven separate surveys between 1990 and 2014 indicated declines in at least six of eight species detected, with large-bodied species hardest hit. Depleted remnant populations of large hornbills mainly persist in two large and relatively well-protected wildlife reserves, Ankasa Resource Reserve and Kakum National Park. Contrastingly, the five largest species of the nine hornbills known to Bia Biosphere Reserve, one of Ghana's few forest wildlife reserves, apparently vanished completely since the 1990s, mainly due to uncontrolled hunting. Similarly, several large hornbills have disappeared from forest reserves where hunting is widespread. We conclude that uncontrolled hunting is the major driver of the recent drastic declines and population extirpations of large hornbills, while reductions in small insectivorous species may be related to extensive fragmentation and habitat disturbances of the Ghanaian forest biome. We call for urgent conservation action to prevent further declines and impending extirpations of forest hornbills and other wildlife in West Africa. © 2018 Elsevier Ltd