The state of biodiversity in Ghana: Knowledge gaps and prioritization
Abstract and Figures
Biodiversity conservation in tropical countries is of great importance due to high levels of endemism. Over the past century, Ghana has reserved over 300 ecologically important areas for biodiversity conservation, and a national strategy for this purpose has been developed under the framework of the Convention on Biological Diversity. However, inadequate relevant information has been a drawback to implementation. This paper synthesizes relevant occurrence records of species, together with recently published data, and provides a current overview of the country’s biodiversity. A map of the distribution of biodiversity study sites in recent years, the taxa studied, total richness of each taxonomic group (except microbes) and list of the species, are presented. The results indicate that in addition to insufficient off-reserve biodiversity knowledge, its acquisition over the past two decades covers only less than 40% of the protected reserves. It is argued that, with the current low-level of protection in protected areas, it is necessary to prioritize agro-ecological studies in order to obtain the baseline data needed for developing effective land-use strategies, as well as the right information to attract the voluntary participation of the public in biodiversity conservation.
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... Together, these can help identify priorities for future PA expansion and management in the two countries and the region more generally. This contributes to an assessment of the future developmental threat of agricultural expansion faced by the PAs of different countries and across different PA categories and is also required to develop data-driven conservation plans [47]. ...
... Around 15% of Ghana's land is protected, and the Wildlife Division of the Forestry Commission is responsible for PAs [47]. An IUCN assessment of management effectiveness for eight PAs concluded that there is a "fair representation" of all ecosystems from the Guinean savanna woodland to evergreen forests [49]. ...
... Steeper slope representation is limited, with only the Kyabobo PA located in a high montane range. There are gaps in biodiversity data for many taxa in Ghana [47] and across West Africa [50], though larger mammals may be the best recorded [51]. In Ghana, 23 mammal species are categorized as threatened on the IUCN "Red List" [13], and the chimpanzees in Ankasa Resource Reserve and lion populations in Mole NP are vulnerable [49]. ...
One of the major threats facing protected areas (PAs) in hyper-diverse tropical forest ecosystems is human modification of their natural habitats. With a focus on forested PAs situated across three of the world’s major tropical regions, the Congo Basin, insular Indonesia Malaysia and the Tropical Andes. We analyse their representation of identified ecoregions and remote sensing data of human modification and forest integrity levels within PAs and used a generalized linear modelling approach to estimate the influences on these pressures, with a particular focus on IUCN management categorisation, PA size, and geographic location. Representation of key ecoregions varied with 7%, 11% and 22% of named ecoregions being unprotected within each major region. Overall, the IUCN management category allocation played a minor role in influencing the modification and forest integrity observed within PAs. Instead, PA size was the most important determinant of these variables across the different regions under consideration. This work provides further evidence to suggest that the assignment of PAs to IUCN categories in their current form is not interpreted consistently across different regions and does not correspond to the conservation benefits expected to be conferred by this categorisation.
... Together, these can help identify priorities for future PA expansion and management in the two countries and the region more generally. This contributes to an assessment of the future developmental threat of agricultural expansion faced by the PAs of different countries and across different PA categories and is also required to develop data-driven conservation plans [47]. ...
... Around 15% of Ghana's land is protected, and the Wildlife Division of the Forestry Commission is responsible for PAs [47]. An IUCN assessment of management effectiveness for eight PAs concluded that there is a "fair representation" of all ecosystems from the Guinean savanna woodland to evergreen forests [49]. ...
... Steeper slope representation is limited, with only the Kyabobo PA located in a high montane range. There are gaps in biodiversity data for many taxa in Ghana [47] and across West Africa [50], though larger mammals may be the best recorded [51]. In Ghana, 23 mammal species are categorized as threatened on the IUCN "Red List" [13], and the chimpanzees in Ankasa Resource Reserve and lion populations in Mole NP are vulnerable [49]. ...
This study assesses the representation of defined ecoregions, slope profiles, and species richness of threatened mammals in the International Union for Conservation of Nature (IUCN)-listed protected areas in Ghana and Côte d’Ivoire. It also evaluates the exposure of protected area categories to the cumulative degree of human modification and their vulnerability to future agricultural expansion. Spatial gap and statistical analyses were performed using quantitative data from publicly available online global databases. Analyses indicated key conservation priorities for both countries: (1) to increase the protection of the Guinean forest–savanna mosaic, West Sudanian savanna, and Eastern Guinean forests, especially of the Eastern Guinean forests’ ecoregion associated with the Guinean forests of the West Africa biodiversity hotspot; (2) to increase the protected area coverage of flat lands and low slopes; and (3) to enhance the size and connectivity of existing protected areas, including restoring degraded habitats. The study emphasizes that improving the ability of tropical protected areas to conserve nature and mitigate anthropogenic threats should be a global conservation priority. Improving the data quality and detail within the World Database on Protected Areas and ground-truthing them are recommended urgently to support accurate and informative assessments.
... Though there are several studies on environmental and natural resources protection and sanitation in Ghana, not much have focused on the implementation of the provisions of the CBD and how it relates to sustainable development and international law. Moreover, the existing studies on biodiversity conservation in Ghana usually focus on the scientific aspect (natural science) and conservation practices, as well as taxonomy, and have not attempted linking it to law or international law in that regard, neither have they focused on identifying existing policies that address the issue (Acheampong et al., 2021;Amoah & Korle, 2020;Bossart et al., 2006;Gordon et al., 2000;Hackman, 2014;Hens & Boon, 1999;Okley, 2004;Opuni-Frimpong et al., 2021;Osei-Tutu et al., 2014). Consequently, several gaps remain on the subject as far as the implementation of the CBD in Ghana is concerned and it is some of these gaps that this study sought to fill (see also Botchway & Hlovor, 2019). ...
This article discusses the efforts made to ensure the implementation of the Convention on Biological Diversity (CBD) in Ghana. The discussion is based on analysis of primary data gathered through interviews and analysis of several official reports, policy documents, legislative instruments, and Acts of Parliament of Ghana that pertains to environmental protection, biodiversity conservation, and sustainable development. The findings have been presented in a way that portrays the various efforts that have been made over the years to enhance sustainable development as the country makes efforts to implement the CBD. They are also linked to the extant literature on the subject of biodiversity conservation, environmental management, and sustainable development. The themes for presentation thus include the passage of several legislations, rules and regulations, and the implementation of targeted sustainable development-oriented policies. The article presents the gains made in the implementation of the CBD and lessons that can be learnt.
... In many cities in developing countries, issues of urban biodiversity are considered subsidiary to more pressing issues such as unemployment, poverty alleviation etc. and in the few instances where biodiversity is of high priority, the emphasis is often on specific ecosystem goods and services (Anderson et al. 2013). In many cases in Africa, national biodiversity strategies and assessments neglect urban biodiversity (Ministry of Environment Science and Technology 2013;Hackman 2014). And although urban biodiversity in developing countries remain threatened by neglect and indiscriminate establishment of buildings, it is worthy to note that majority of the urban poor depend on these remnant ecosystems in cities for their livelihoods and wellbeing (Cilliers et al. 2013). ...
Urban biodiversity is essential to creating resilient and sustainable cities. Nevertheless, there is paucity of data on the characterization of microhabitat effects on species/trait diversity and diversity-functional relationships in urban landscapes especially in developing countries. The objectives of this study were to; 1) analyze tree species diversity and composition of urban green space (UGS) types and urban zones, (2) describe the life history diversity of UGS types and urban zones and 3) examine the links between species and life history trait diversity and species productivity (carbon storage) in Kumasi, Ghana. Stratified random sampling was adopted in surveying 470 sampling plots and six streets of lengths ranging from 50 m to 1 km. About 176 tree species in 46 families were recorded within Kumasi. About 96 species were in an adjacent natural forest located at the outskirts of the city. Home gardens, institutional compounds, and public parks had the highest species richness of 76, 75 and 71, respectively while urban rangelands and farmlands were the least species rich with 6 and 23, respectively. Species richness (S) in the peri-urban (LDUZ, S = 142) and core urban (HDUZ, S = 108) were significantly different (Χ² = 15.7, p < 0.0001, n = 1). Native species richness was lowest in the core urban area and highest in the natural forest. Pioneers and anthropochory dispersed species were the most abundant, suggesting that this urban landscape is shaped by both environment and social filters. Tree species diversity and distribution depend on the type of UGS and portrays a perturbed landscape in the early seres of succession with the overall ecosystem function sustained by both species and life history trait diversities. The implications of these findings for improving urban biodiversity conservation and overall urban sustainability are discussed.
... The vegetation cover is diversesparse and woody (predominantly in the north) and dense (in the south)and is supported by 21 different soil types, including five major ones. Administratively, the country is divided into 10 regions and has approximately 15.0% of the land under nature protection (Hackman 2014). The land outside the protected areas, apart from built-up areas, is almost completely utilized for farming. ...
Remote-sensing products provide opportunities to monitor complex phenomena on the Earth from space for good decision-making. An example is land-cover maps, which are useful for monitoring both human- and naturally induced environmental changes to enhance environmental management for the benefit of the society. Yet there are numerous critical areas of the world such as biodiversity hotspots where the inaccessibility of quality satellite images has hindered progress in our understanding and management of the natural environment. The West African biodiversity hotspot is one such area where persistent thick clouds in freely available satellite images has been a great discouragement to the production of local land-cover maps to monitor the ongoing deforestation and rapid environmental change. Ghana is a country in West Africa where no land-cover map (except global ones) has been published for over a decade although large tracts of land have been converted from their natural states to agricultural land. In this article, we present 30 m land-cover maps of the country using Landsat 8 images and three popular classifiers – Maximum Likelihood Classifier (MLC), Support Vector Machines (SVMs), and random forest (RF) – for the year 2015. We produced these maps for use in our future biodiversity assessment in the region. An overall accuracy (OA) of 85.5% (kappa = 0.77) was achieved for MLC, with similar but slightly lower accuracies for RF and SVM, which indicates that advanced classification algorithms may not have many advantages when applied to process only multispectral optical data. We observe that shrublands, croplands, and orchards are the dominant classes occupying 35.6%, 31.9%, and 18.4% of the country’s land area, respectively. This further indicates that
50.0% of the country’s land area is under agriculture. Thick forests occupy only 8.0% of the land and are almost entirely confined to forest reserves, highlighting the usefulness of these nature reserves. Our maps will provide input for research advancement, policy formulation, and environmental management at both national and subnational levels.
Recent concerns to strengthen the role of Tropical Botanic Gardens (TBGs) in conservation are constrained by inadequate representation of models of best practices. This also presents minimal opportunities to explore and fully appreciate the contribution of botanic gardens to biodiversity conservation, especially in urban landscapes. We contribute to addressing this issue using the KNUST Botanic Garden. The study explores biodiversity variation in two microsites (upland and inundated areas), within the context of threats from urbanization. The composition, diversity, and conservation status of plants were assessed from three 50 × 50 m plots each located at the two microsites. A total of 78 adult plant species were recorded, with 87.2% native and 12.8% exotic species. Some species were exclusively recorded at the upland (29 species) and inundated (27 species) microsites. On average, the species diversity was significantly high (HI = 3.36). The botanic garden preserves 20 nationally threatened native species, with over half of them listed in the IUCN Red List category of vulnerable species (species facing high risk of extinction in the wild). A considerable number of threatened species were exclusive to the upland (10 species) and inundated (7 species) microsites. The results indicate that the Botanic Garden could play a critical role in biodiversity conservation if integrated into national conservation and urban development strategies to safeguard its potential. The findings of the study are discussed within the context of the contribution of botanic gardens to biodiversity conservation and holds applications for sustainable management of TBGs in urban landscapes.
Despite the rapid urban transformation in green space in most cities in Ghana, knowledge on urban tree diversity and the evidence of the consequences of built-up expansion on trees is scanty. This article provides a novel contribution to the current urban trees abundance and richness in Kumasi Metropolitan Area, Ghana. Post classification change detection technique was applied to quantify urban land use land cover (LULC) transformations (urban forest, agricultural, riparian vegetation and built-up) from 2007 to 2017. Species rank abundance distribution and richness were quantified using geometric series and individual-based rarefaction models. A total of 858 individual trees belonging to 76 taxa were recorded across the four LULC classes. Species abundance distributions in three LULC types varied substantially, with the exception of riparian LULC (slope [k] = 0.086 ± 0.12, χ²P = 19.42, P = 0.15). Land use pressure led to a 13.56 km² reduction in forest cover, while built-up and agricultural LULC increased by 31.13 and 1.85 km², respectively. These disturbances did not only affect indigenous tree dominance (41.3%) in favour of exotic species (58.7%) in the agricultural and built-up LULC types but also impacted on tree abundance (n = 126) and richness (n = 28) in agricultural land compared to abundance (n = 280) and richness (n = 67.86) in forest cover. Despite the contribution of LULC transformation to increase in tree diversity, there is the likelihood of future dominance of exotic species in the Metropolis if urban planners do not institute measures to conserve indigenous species.
Conserving biodiversity in cities is essential to halting global biodiversity loss. Nevertheless, there is paucity of data on the underlying mechanisms shaping species assemblages and species/trait diversity-productivity relationships in urban landscapes. The objectives of this study were to; 1) compile tree species diversity of different green space (GS) types, (2) describe the theoretical basis of species co-existence and 3) examine the links between species and life history trait diversity to GS and species productivity (carbon storage) in Kumasi, Ghana. Stratified sampling and species abundance models were combined in this study.
About 176 tree species in 46 families were recorded within Kumasi. About 96 species were in a natural forest located towards the outskirts of the city. Home gardens, institutional compounds, and public parks had the highest species richness of 76, 75 and 71, respectively while urban rangelands and farmlands were the least species rich with 6 and 23, respectively. Species richness (S) in the peri-urban (mean ndvi >0.2, S=142) and core urban (mean ndvi<0.2, S=108) areas were significantly different (X2 =15.7, p< 0.0001, n=1). Native species richness was lowest in the core urban area and highest in the neighbouring natural forest. The geometric series model best fitted the tree assemblage of the city, depicting a species impoverished and environmentally hash landscape. Pioneers and anthropochory dispersed species were the most abundant suggesting that this urban landscape is shaped by both environment and social filters.
Plant species diversity and distribution depend on the type of green space and portrays a perturbed landscape in early seres of succession with the overall ecosystem function sustained by both species and life history trait diversities.
There is a global consensus on the fact that human activities are increasingly eroding biodiversity, especially in many ecologically rich regions of the world. Quantifying these biodiversity losses over large administrative areas, along with the impacts of the respective driving factors is necessary for biodiversity conservation. In this study, we used readily available spatial data on infrastructure, fragmentation, and land use together with ecological data on terrestrial arthropods (as species surrogate) to carry out spatial assessment and mapping of biodiversity values in the Western Region of Ghana, a highly degraded part of the West African biodiversity hotspot. Compared with its pristine condition, our results show that the region has a remaining mean species abundance (MSA) of approximately 52%, indicating a loss of 48% due to anthropogenic activities (mainly cocoa and oil palm farming). Areas of national protection (i.e. national parks and forest reserves) did not prove to have much promise for biodiversity conservation in the region since many were found to have low MSA values. Moreover, according to our arthropod data, no areas of high MSA values were found outside protected areas. However, because the thick, continuous, structurally complex canopies of these orchards responsible for the biodiversity loss provide natural connectivity between protected reserves, diversification of understory vegetation and a reduction in the use of agrochemicals particularly weedicides and pesticides may yield significant conservation outcomes.
Context
The assessment of land-use impacts on biodiversity is one of the central themes of landscape ecology and conservation biology. However, due to the complexity of biodiversity, it is impossible to obtain complete information about the diversity of all species even for small areas, necessitating the selection of individual species or assemblages thereof as species surrogate. In parts of the world where taxonomic expertise is lacking, species identification has hindered progress in biodiversity conservation, and the only practical, relatively-accurate option, is the use of taxonomic minimalism.
Objective
We carried out a rapid biodiversity assessment based on three surrogates—land-use (driver-surrogate), terrestrial arthropods (species-surrogate) and morphospecies (taxonomic-surrogate)—to determine the impacts of land-use on biodiversity of the Western Region (Ghana), an area covering ~4 % of the West African biodiversity hotspot.
Method
We used diversity profiles to visualize the distribution of a total of 8848 arthropod individuals over seven land-use types which define the complete heterogeneity of the landscape.
Results
Here, we present both sample and asymptotic diversity profiles of arthropod morphospecies for each land-use type and the potential of each land-use type for conserving arthropods.
Conclusions
We conclude that (1) the morphospecies approach is useful for detecting differences in species diversity of land-use types; (2) the concept of asymptotic diversity may not be necessary for land-use based biodiversity comparison; and (3) maximum diversity profiles are useful for determining the land-use conservation values in cases where pristine areas are not available.
An inventory was conducted in the Ajenjua Bepo and Mamang River forest reserves to determine the species richness of large mammals within the reserves. Line transects were used to survey large mammals within the two reserves and interviews were conducted in nearby villages. A total of 16 mammal species were directly observed, all 16 being present in Mamang River and 10 in Ajenjua Bepo. Of these, three species are considered to be Near Threatened on the IUCN Red List (July 2008): Maxwell's Duiker Cephalophus maxwelli, Black Duiker C. niger and Pel's Anomalure Anomalurus pelii. Interviews suggested the possible presence in Mamang River of an additional seven species, including three more species of conservation concern: Olive Colobus Procolobus verus, Black and white Colobus Colobus polykomos and Royal Antelope Neotragus pygmaeus, all considered Near Threatened. Forest canopies of both reserves are open and habitat has been degraded through farming and hunting activities. Many footpaths were noted in both reserves. Hunting, indiscriminate of national wildlife laws and regulations, is a considerable threat to the remaining species of large mammals within these reserves. Suggestions are made for improvement of biodiversity conservation in the reserves including alternative livelihoods.
INTRODUCTION
Biodiversity conservation in Ghana is in a critical state as a result of severe hunting pressure, accelerating timber extraction and escalating population pressure which have led to encroachment of primary forests, reducing them to small refuges in which the biota struggles to survive (Grubb et al. 1998). As a result of these pressures, forests are opened up to agriculture, further restricting the survival of many large mammal species. Many areas in the country have lost their endemic wildlife species as development activities have encroached on the land depriving many large mammals of necessary habitat (Parren and de Graaf 1995). Southern Ghana is exploited for both timber and minerals, often with no consideration for biodiversity conservation. Local communities derive many benefits from the forest for their livelihood as in other parts of West Africa (Sunderland and Ndoye 2004). In Ghana, however, there are few records that show the loss of wildlife species in the country. The purpose of this Rapid Assessment Program (RAP) survey, conducted by Conservation International in the Abirem North District in the Eastern Region, was to undertake an inventory of a number of taxa, including large mammals, in the Ajenjua Bepo and the Mamang River forest reserves.
METHODS
For details on survey sites, see Gazetteer.
Transects were walked daily from base camp to sections of the reserves to determine the presence of large mammal species. Mammal species were recording using both direct observation Rapid Assessment Program of species and indirect observation through identification of footprints and tracks, dung/pellets, feed and feeding sites, and calls of animals to determine their presence. Species identification was based on Kingdon (1997). Old shotgun shells and wire snares used for hunting were also collected. Calls of nocturnal animals were identified during the night in both reserves. One hunter from the Ajenjua Bepo area and three hunters from the Mamang River area were interviewed, as was the large mammal survey guide. The number of old shotgun shells and wire snares was used to assess local hunting pressure within the two forest reserves.
RESULTS AND DISCUSSION
Ten and sixteen large mammal species were identified from Ajenjua Bepo and Mamang River, respectively (Appendix 9). The difference in the number of large mammal species sighted in Ajenjua Bepo and Mamang River is most likely due to the sizes of the reserves. Ajenjua Bepo is a smaller and more disturbed forest than Mamang River. There was no evidence of monkeys in Ajenjua Bepo, due to both its small size and the much higher intensity of hunting and human activities in the area. While Mamang River is larger and has more large mammal species than Ajenjua Bepo, there are numerous footpaths and wire snares in the reserve suggesting intense hunting and human activities. Fewer antelopes were found in Ajenjua Bepo compared to Mamang River. The presence of black duiker and red river hog in Mamang River is probably due to the large habitat of the forest, since habitat fragmentation is one major reason for the decline of large mammal species in the forest zone.
During interviews, hunters reported the presence of 23 species of large mammals in Mamang River (Appendix 9). The reported list is similar to the list of species recorded during the survey in Mamang River (interviews indicated the possible presence of seven species not recorded during our survey). However, both the recorded list and the list resulting from interviews differs greatly from the list given by Grubb et al. (1998) which listed about 40 species of large mammals found in the area. Many large mammal species have been exploited locally and are likely to have been driven to local extinction during the past century (Lee et al. 1988, Wilson 1994). The IUCN Red Data book lists many animals found in Ghana that are threatened, endangered or extinct (IUCN 1990). Indiscriminate hunting and clearing of forest for agricultural purposes have both played major roles in causing the decline and extinction of wildlife species in the area.
There are clear signs of indiscriminate hunting in both reserves. The old shotgun shells and wire snares found in the reserves testify to this. People hunt without game licenses, and many are not aware of the closed season on hunting as stipulated in national wildlife regulations. However, there was no sign of bushmeat trade in the communities around the reserves. The interviewed hunters said that they do not sell bushmeat but use it for home consumption. The scarcity of animal protein in many Ghanaian villages is very real, leading to a high demand for bushmeat in Ghana (Asibey 1974, 1976; Ntiamoah-Badu 1998), as in many countries in West Africa (Jeffrey 1977, Ajayi 1979, Martin 1983, Falconner and Koppell 1990, Bakarr et al. 2001).
Local communities have easy access to both reserves. In Mamang River, the logging operations of about 10 years ago, through the creation of numerous associated paths/routes in the reserve, have opened the area to activities such as hunting and farming. There are farms within the northern sector of the forest reserve boundaries. Such activities are all major causes of degradation within the forest and loss of biodiversity. In Ajenjua Bepo, farming activities have encroached within the forest reserve boundaries. This has resulted in a loss of large mammal species. Ajenjua Bepo is undergoing reforestation but similar past attempts have not shown much success within Ghana.
Interesting species or genera
Many mammal species were not observed, likely as a result of hunting and forest degradation. The Gambian sun squirrel and the potto are not very common in Ghana. It is important to conduct an inventory of these species in the forest reserves and other vegetation types in Ghana. The black duiker seems threatened in Ghana as hunting and habitat destruction are prevalent throughout its range. The black duiker is not adaptive to habitat changes like maxwell's duiker and will decline in such disturbed habitats.
CONSERVATION RECOMMENDATIONS
Ajenjua Bepo Forest Reserve
All efforts should be made to replant the portion of the Ajenjua Bepo reserve that has been farmed, with regular patrols to monitor hunting activities in the reserve. The reserve should be enlarged and logging activities should be stopped in order for the reserve to be ecologically viable for mammal species. Alternative sources of livelihood should be developed, in collaboration with the Forest Service Division (FSD), to assist local communities in obtaining animal protein. Grasscutter farming and snail rearing could be introduced into the communities as alternative sources of livelihood that provide necessary protein, and beekeeping could be encouraged as well. If mining activities proceed in the reserve, an environmental impact assessment should be conducted to identify the biodiversity conservation problems of the area and also to determine the development needs of local people.
Mamang River Forest Reserve
Agricultural activities occurring within the reserve boundaries in in the northern sector of the reserve should be stopped and the reserve should be protected and managed for biodiversity conservation. Access to the reserve should be restricted and hunting activities regulated. Alternative livelihoods, such as grasscutter farming and snail rearing, should be encouraged in nearby communities to give the people a source of protein. Exploitation of non-timber forest products should be regulated. Efforts should be made to conserve this forest are important as most other nearby forests have been seriously degraded and no longer offer habitat needed for the maintenance of large mammal populations.
There is no doubt that the West African rainforest is highly threatened by logging, agriculture, mining, and increasing human populations which have all led to habitat fragmentation. The results of this fragmentations has been the decline and local extinction of wildlife, particularly large mammals. Biodiversity conservation is urgently important in West Africa as many forest and wildlife resources are being depleted quite rapidly. Very few species of large mammals were identified in the two forest reserves and hunting pressure is very high. Wildlife regulations are not observed by inhabitants living around the two reserves who have acknowledged hunting without appropriate licenses and disobeying (through a lack of awareness) regulations on the season closed to hunting. These activities have depleted the large mammal resource in both reserves. Local people should be educated with regard to wildlife regulations and procedures for hunting and encouraged to obtain appropriate game licenses. Local conservation education is extremely important in order to sustain biodiversity conservation in the area.
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Appendices
Fifty-six species of Tettigoniidae were collected, of which 13 are new to science, and, in addition to these, 12 are new species records for Ghana. Ajenjua Bepo shows a higher species count (50 species) than Mamang River (33 species), most likely a result of higher fragmentation of the habitat and a stronger edge effect in Ajenjua Bepo compared to that within Mamang River.
INTRODUCTION
Katydids (Orthoptera: Tettigoniidea) have long been recognized as organisms with a significant potential for their use in conservation practices. Many katydid species exhibit strong microhabitat fidelity, low dispersal abilities (Rentz 1993a), and high sensitivity to habitat fragmentation (Kindvall and Ahlen 1992) thus making them good indicators of habitat disturbance. These insects also play a major role in many terrestrial ecosystems as herbivores and predators (Rentz 1996). They are themselves a principal prey item for several groups of invertebrates and vertebrates, including birds, bats (Belwood 1990), and primates (Nickle and Heymann 1996). At the same time many species of katydids are threatened and some appear to have already gone extinct (Rentz 1977).
The conservation value of katydids has been recognized in Australia (Rentz 1993b) and Europe, leading to the development of captive breeding programs (Pearce-Kelly et al. 1998), listings on country (Glowacinski and Nowacki 2006) and global Red Lists (IUCN 2006), and introduction of regulations aimed at their conservation. But their use as conservation tools or targets of conservation actions in tropical regions, where their importance and the level of endangerment are the highest, is hampered by the lack of baseline data on katydid distribution as well as the shortage of katydid expertise and identification tools, a phenomenon known as the taxonomic impediment. It is therefore critically important that more effort is directed towards basic faunal surveys of katydids across the tropics, thus creating the basis on which a successful conservation strategy for these animals can be built. Such surveys, if conducted in pristine or relatively undisturbed areas, also provide reference data which can later be used in habitat monitoring or restoration efforts that should follow any industrial or agricultural activity. West African ecosystems are in particular need of extensive biotic surveys, being not only some of the least studied tropical habitats, but also as they are subject to widespread, poorly regulated, and often illegal logging, mining activities, and slash-and-burn agricultural practices. This results in a rapid decline of available natural habitats, and thus an inevitable loss of the biodiversity.
The following report presents the results of a survey of katydids conducted between August 24 and September 4, 2006 at sites within the Ajenjua Bepo and Mamang River forest reserves in the Eastern Region of Ghana. This is only the second systematic survey of katydids in this country, following a rapid assessment survey of the Atewa Range in June 2006, and its results indicate the presence of a rich and unique Ghanaian fauna of the Tettigoniidae. Prior to these two RAP surveys, the only published records of katydids in Ghana are those in the works of Beier (1965), Bolivar (1886, 1890, 1906), Karsch (1888, 1890), Ragge (1962, 1980), and Redtenbacher (1891) who collectively recorded only 13 species of katydids from this country. The Atewa Range survey documented 61 species, of which at least 36 were new to Ghana, and 8 were new to science (Naskrecki 2007). The present survey adds 12 species that are new records for Ghana, and 13 species new to science.
METHODS AND STUDY SITES
The first area covered by the survey, Ajenjua Bepo, is classified as a moist semi-deciduous forest with a total area of 5.69 km2. Approximately 0.74 km2 of the forest lies within a proposed mining area. The overall condition of the forest indicated heavy disturbance due to logging, fire damage, and agricultural activity. Nonetheless, parts of the reserve still support pockets of natural forest, with stands of large, mature trees. In addition to sampling within the forest, katydids were collected on the fringes of the forest along roads and within the plantain plantation inside the reserve.
The second survey area was Mamang River. The reserve covers an area of 53 km2. The forest within the reserve was assessed as Condition 2, reflecting relatively low disturbance and the presence of a large number of mature trees. The area sampled during the present survey was bordering on cocoa, plantain, and citrus plantations. Katydids were collected both deep within the forest and on its edges bordering on the plantations.
During the survey three collecting methods were employed for collecting katydids: (1) collecting at incandescent and mercury vapor (MV) lights at night, (2) visual search at night, and (3) net sweeping of the understory vegetation during the day and at night.
Net sweeping was employed in the vegetation along the roads within the forest, the forest understory, and natural openings within the forest, such as edges of (dried) streams. This method was highly effective for collecting seed-feeding katydids in tall grasses as well as a number of arboreal katydids that cling upside-down to the lower surface of leaves. Sweeping was standardized by performing five consecutive sweeps in a series before the contents of the net were inspected. By far the most effective method of collecting, both in terms of the number of species collected and number of collected specimens, was the visual search at night. Most of the collecting was conducted after dark, between the hours of 8 pm and 2 am when the activity of virtually all katydid species is the highest. Yet day collecting along the forest roads also yielded several interesting species, including one (Ruspolia sp. 1), the presence of which may indicate an encroachment of savanna elements into the reserve. The MV collecting was done nightly between approximately 8 pm and 11 pm. This method yielded a number of canopy-inhabiting Phaneropteridae, Meconematidae, and some Pseudophyllidae.
In addition to physical collection of specimens, stridulation of acoustic species was recorded using the Sony MZ-NHF 800 digital recorder and a Sennheiser shotgun microphone. These recordings are essential to establish the identity of potential cryptic species, in which morphological characters alone are not sufficient for species identification. An ultrasound detector Pettersson D 200 was also used to locate species that produce calls in the ultrasonic range, undetectable to the human ear.
Representatives of all encountered species were collected and voucher specimens were preserved in 95% alcohol and as pinned, dry specimens. These specimens will be deposited in the collections of the Museum of Comparative Zoology, Harvard University and the Academy of Natural Sciences of Philadelphia (the latter will also become the official repository of the holotypes of several new species encountered during the present survey upon their formal description.)
The main collecting site within the Ajenjua Bepo Forest Reserve was located at 6°22′2.3″N, I°1′58″W, at the elevation of 300 m. Sampling was conducted there during the period of August 24–30, 2006. The surroundings of the site contained a relatively undisturbed forest as well as plantain and cocoa plantations.
The second major collecting site was located within the Mamang River Forest Reserve at 6°15′1.4″N, 1°2′25.4″W, at the elevation of approximately 130 m. Sampling was conducted there between August 31 and September 4, 2006. The dominant habitat was a relatively undisturbed deciduous forest, bordering on cocoa, citrus, and plantain plantations. Collecting was done both within the forest and along its edge.
RESULTS
The survey resulted in the collection of 56 species of katydids, the second highest number of katydids known from a single location anywhere in Africa, following only the results of the survey in the Atewa Range. Many collected species represent new records for Ghana, and 12 species are new to science. Many species listed here appear to have a wide, West African distribution, having been recorded from sites in Cameroon and Guinea. Their presence in Eastern Ghana supports this notion, and fills a gap in our knowledge of West African biogeography. A full list of recorded taxa is given in Table 4.1, and below I comment only on new or particularly interesting species. When a discussed species was recorded from only one site, this is indicated at the end of the description by (AB) or (MR) for Ajenjua Bepo and Mamang River respectively.
Family Phaneropteridae
This group of katydids includes most species restricted to the canopy level of the forest. Many are excellent fliers, and can be collected at night using UV, MV, or incandescent lights. Some are diurnal and can be heard calling during the day from tall trees. All members of this family are exclusively herbivorous. Twenty-seven species of this family were found during this survey.
Catoptropteryx extensipes Karsch, 1869 — This species was originally described from Lolodorf in Cameroon, and this is its first record from Ghana (AB).
Table 4.1. Katydids recorded from the Ajenjua Bepo and Mamang River forest reserves, Eastern Region of Ghana
continue
Arantia spp. — Seven species of this genus were recorded, one of which is new to science; in addition to the new one, four species are new to Ghana. They were all associated with tall understory vegetation within the forest as well as tall, broadleaved plants along the roads.
Preussia lobatipes Karsch, 1890 - This species was previously reported from the Atewa Range Forest Reserve (Naskrecki 2007). During the present survey a single female was collected at the Mamang River (MR).
Family Conocephalidae
The Conocephalidae, or the conehead katydids, include a wide range of species found in both open, grassy habitats, and high in the forest canopy. Many species are obligate graminivores (grass feeders), while others are strictly predaceous. A number of species are diurnal, or exhibit both diurnal and nocturnal patterns of activity. Four species of this family were recorded.
Conocephalus carbonarius Redtenbacher, 1891 — This species is one of the few true forest species of the genus. Individuals of C. carbonarius were common in the understory of forests at both sites, but were particularly abundant along roads and in herbaceous vegetation along the edges of the forest. Unlike most species of the genus Conocephalus, males of C. carbonarius are active both day and night, singing from vegetation very low to the ground. This species appears to be predominantly predaceous. It was originally described from Ghana (Redtenbacher 1891), and was subsequently found in Guinea (Chopard 1954).
Plastocorypha vandicana Karsch, 1896 - This is the first record of this species from Ghana. It is a forest specialist, found only in relatively undisturbed habitats (MR).
Family Listroscelididae
“Within Africa this family is represented by only 13 species, all obligate predators of insects. In West Africa only the genera Hexacentrus and Afrophisis have been recorded.
Hexacentrus alluaudi Bolivar, 1906 - This is the first record of this species from Ghana; it was previously known only from the type specimens collected in Côte d'Ivoire (Bolivar 1906.)
Family Meconematidae
This poorly studied family includes some of the smallest species of katydids, and many appear to be exclusively predaceous. Nearly all species of Meconematidae are arboreal, nocturnal, and extremely agile, making it very difficult to collect them (many are flightless, and thus rarely come to lights at night.) Five species were recorded, all representing yet undescribed species. Eight species of the genera Amyttopsis, Amyttosa, Gonamytta and Xiphidiola. were recorded,five representing species new to science (since described in Naskrecki 2008b.). They appear to be associated with the forest canopy, and could only be collected by using the MV lamp at night.
Family Mecopodidae
Three species of this exclusively tropical group of katydids were found during this survey. Most of its species are associated with humid forests, and all species appear to be herbivorous. No members of this family have ever been recorded from Ghana, although their presence there is not surprising as they are known from most of the neighboring countries.
Afromecopoda spp. — Two species of this genus were collected, and one appears to represent a species new to science. A. frontalis (Walker) was found to be common at both sites. Members of this genus are some of the few West African katydids associated with leaf litter and the bottom of evergreen and deciduous forests.
Corycoides abruptus (Krauss, 1890) — This interesting species is known only from the holotype from an unknown locality and a handful of specimens collected in Guinea (Chopard 1954). It was also recorded during the previous RAP survey in the Atewa Range in SE Ghana (Naskrecki 2007). Within the sampling sites it was common along the edge of the forest on trees, where males were heard calling at night from the height of 3–5 m above the ground. An opportunistic insectivory was observed in this species, the first such case among species of the family Mecopodidae.
Family Pseudophyllidae
Virtually all members of tropical Pseudophyllidae can be found only in forested, undisturbed habitats, and thus have a potential as indicators of habitat changes. These katydids are mostly herbivorous, although opportunistic carnivory was observed in some species. Many are confined to the upper layers of the forest canopy, and never come to lights, making it difficult to collect them. Fortunately, many of such species have very loud, distinctive calls, and it is possible to document their presence based on their calls alone, a technique known well to ornithologists. Twelve species of this family were collected during the present survey.
Cymatomera modesta Chopard, 1954 - The genus Cymatomera is a primarily East African taxon, and with the exception of a single species in Angola, C. modesta is the only species ever found west of Zaire. Previously C. modesta has been known only from the holotype female collected in the Mt. Nimba region of Guinea (Chopard 1954), and the male specimen collected at Ajenjua represents both the first record for Ghana, and the first male specimen ever collected. This species is a remarkable bark mimic, virtually invisible when resting on tree trunks during the day (AB).
Tomias spp. e— Two species of this genus were recorded, one of which was new to science; it has since been described as T. gerriesmithae Naskrecki (Naskrecki 2008a.) The second species, T. hadrus Karsch, has not been recorded west of Cameroon before and its record from Ghana is new to this country. Genus Tomias belongs to one of the least known genera of the Pseudophyllinae and is rarely collected.
Adapantus spp. — Two species of this genus were recorded, one of which was new to science; it has since been described as A. pragerorum Naskrecki (Naskrecki 2008a). Species of this genus appear to be associated with undisturbed forest, and were never collected in areas where intensive logging or encroachment of secondary vegetation was present. This may indicate their value as species indicative of habitat disturbance.
CONSERVATION IMPLICATIONS
Both surveyed reserves showed disturbance caused by fire damage, logging, or even complete removal of forest vegetation. In addition, roads and plantations within the reserves allow for non-forest elements, such as the genus Ruspolia, to penetrate this habitat. Nonetheless, both reserves still harbor an interesting and rich fauna of katydids, including many rare or even yet undescribed species, and every effort should be made to stop the removal of the tree coverage within the reserves. Between the two reserves, Mamang River has a significantly larger area, and thus a higher potential for preservation of the biotic elements still present there. While Ajenjua Bepo has a more topographically diverse terrain, with pockets of virtually pristine forest, its small size, and the fact that over 13% of its area is a part of the Newmont mining concession makes it a less promising candidate for conservation efforts focused on preservation of intact biological communities.
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Large mammals were surveyed at three sites in the Atewa Range Forest Reserve from 7 – 23 June 2006. Altogether, 22 species were recorded with 12, 14 and 15 species observed from Atiwiredu, Asiakwa South and Asiakwa North respectively. Of the species recorded, Pel's flying squirrel (Anomalurus pelii) is listed as Near Threatened, Yellow-backed duiker (Cephalophus silvicultor), Black duiker (Cephalophus niger), Bay duiker (Cephalophus dorsalis), Maxwell's duiker (Cephalophus maxwellii) and Royal antelope (Neotragus pygmaeus) are listed as Lower Risk/Near Threatened, and West palm squirrel (Epixerus ebii) is listed as Data Deficient on the IUCN Red List. In addition to these species of international conservation concern, the African civet (Civettictis civetta), African palm civet (Nandinia binotata), Long-tailed pangolin (Uromanis tetradactyla) and Yellow-backed duiker (Cephalophus silvicultor) are nationally protected in Ghana. Interviews in selected fringe communities indicated that there could possibly be four other mammal species present in the reserve while five others could be locally extinct. Many illegal activities, especially related to hunting, were recorded during our assessment. It was also noted that deforestation along trail lines being constructed for mineral exploration and occasional illegal farms could be a significant factor affecting the conservation of large mammals in Atewa.
INTRODUCTION
At a time when deforestation is accelerating across Africa, survey information is particularly important for assessing and monitoring the long-term effects of habitat changes. Research and monitoring must anticipate the changes that lie ahead so that wildlife managers can prepare themselves. The challenge for biologists is not only to preserve species and representative biological communities for posterity, but also to conserve ecosystems that are large enough to continue providing the natural products and services that are essential for human communities.
As in many other countries in West Africa, wildlife resources in Ghana have dwindled drastically over the past few decades. This has largely been attributed to the growth in human population and poor enforcement of the country's wildlife laws, which combined has resulted in a virtually uncontrolled bushmeat trade, posing a major threat to biodiversity in general and to wildlife resources in particular. Consequently, many of the country's wildlife species such as duikers (forest antelopes), porcupine, tree pangolin, bare-headed rock fowl, forest elephant and primates have become threatened. Current estimates suggest that at least 20 of the larger mammal species in the forest zone of Ghana are globally threatened (Ntiamoa-Baidu 1987).
The large mammals of the Atewa Range Forest Reserve (Atewa) make an interesting case study for several reasons. The forest reserve belongs to the Upland Evergreen Forest type which is quite restricted in Ghana, with only one other example, Tano Ofin Forest Reserve, in the Ashanti Region of Ghana. The uniqueness of the terrain and microclimatic conditions there-fore predispose the reserve to many interesting fauna and flora.
During this survey, our aim was to investigate the large mammal (mammals larger than bats) population of Atewa using Rapid Assessment Program (RAP) survey methods. Measuring biodiversity is a difficult, expensive and time-consuming task (Hawksworth 1995), and hardly feasible in the case of most tropical forests. Practical considerations mean that we must use particular groups of organisms as biodiversity indicators (Pearson 1995). For a project of modest duration, large mammals are one important and diverse group that can readily be inventoried. They fulfill most of the criteria listed by Pearson (1995) for a good indicator group for monitoring. According to White and Edwards (2000), as a focal group, large mammals and their signs are most readily visible. They tend to be the most heavily hunted animals and are therefore of special conservation concern. They also tend to be a good index of the overall integrity and conservation status of a region.
METHODS
From 7–23 June 2006 Atewa's large mammals were surveyed at three different sites (Atiwiredu, Asiakwa South and Asiakwa North) using a straight transect of least resistance. To determine the presence of species, visual observations of mammals and other signs of their presence such as tracks, droppings, dung, feeding signs, walking trails and nests were noted. The team also noted evidence of activities such as hunting, illegal farming and other such activities that impact the conservation of large mammals. A species list was generated including species that were observed through direct sightings, sounds and/or animal spoors, from transects of all areas surveyed.
To complement information from transect walks, interviews were conducted in forest fringe communities such as Ankaase and Anyinam to determine the presence or absence of previously recorded mammals. These interviews indicated the possible local extinction of some species previously known to occur in the area. Individuals selected for interview included those with extensive knowledge of the local fauna who had lived in the various communities for many years as well as seasoned hunters. A species list based on interviews with local community members was generated taking into consideration historical presence of recorded species.
The first site surveyed was Atiwiredu. This site has tree species endemic to Atewa, such as Aframomum atewae. Cola boxiana and Chidlowia sanguinea are two of the most dominant tree species at the site. In this area, ALCOA has been actively prospecting for bauxite. As a result of this, many roads have been constructed to enable transportation of personnel and equipment to the various parts of the site. The forest condition is rated 2 despite this development, indicating that the area is still in good shape.
Asiakwa South was the second site surveyed with a forest condition score 3. Some of the dominant tree species at the site are Rinorea oblongifolia and Hymenostegia afzelii. It is in slightly better condition than Site 1 in terms of habitat fragmentation, number of roads and automotive noise. This site shows evidence of previous prospecting work and lumbering operations, with clearly demarcated old roads which have given way to the development of forest undergrowth and other opportunistic plants. There are no signs of previous farming activities. Visibility here was about 10 m.
Asiakwa North was the third site surveyed. One of the most dominant tree species observed at this site was Rinorea oblongifolia. Of the three sites, this site had the highest quality habitat (condition score 2) with a fantastic dense evergreen canopy. Although there is evidence of illegal chain-saw activities here, this area contains no lumbering roads and access is restricted to footpaths. Resulting from the intactness of the canopy, the understorey is relatively clear increasing both accessibility and visibility which could be beyond 10 m at this site.
RESULTS
Overall, a total of 140 actual sightings and signs of animals indicating the presence of 22 different mammal species in five families were recorded during transects of the three sites. Rodentia was the most dominant family and accounted for eight of the recorded species while six species each of Artiodactyla and Carnivora were recorded and just one species each of Pholidota and Hydracoidea. Interviews indicated the possible presence of an additional four species in the reserve including Greater cane rat (Thryonomys swinderianus), Marsh mongoose (Atilax paludinosus), Dwarf mongoose (Helogale parvula) and Red river hog (Potamochoerus porcus). Interviews also suggested that five other mammals, believed to be present in Atewa but not encountered for over 20 years, are likely to be locally extinct. These include Bongo (Tragelaphus euryceros), Ogilby's duiker (Cephalophus ogilbyi), Water chevrotain (Hyemoschus aquaticus), Giant forest hog (Hylochoerus meinertzhageni) and Crested porcupine (Hystrix cristata senegalica).
In terms of large mammal observations, the greatest number of records came from Asiakwa North (15 spp.) followed by Asiakwa South (14 spp.) and finally Atiwiredu (12 spp.). Six species were common to all three sites, with nine species recorded at two sites and seven species recorded at only one site (see Table 12.1). Maxwell's duiker (Cephalophus maxwellii) was the most frequently observed species and accounted for about one-third (38 observations) of all detections followed by the Brush-tailed porcupine (Atherurus africanus) with 21 observations. The indices of animal signs were 2.9/hr, 2.67/hr and 1.41/hr for Asiakwa South, Asiakwa North and Atiwiredu respectively. Asiakwa North recorded the highest index of illegal activity (i.e total number of signs of illegal activities encountered per hour of survey) of 1.87/hr, followed by Atiwiredu with 1.07/hr and Asiakwa South, 1.05/hr.
DISCUSSION
Roads have left the habitats of the Atiwiredu site fragmented. There is also evidence of previous logging of economically important tree species. This has given way to growth of undercanopy plants making accessibility difficult and visibility under the canopy less than 10 m. Some spent cartridges, snares and hunting trails were encountered at this site.
Table 12.1. Preliminary Checklist of the Large Mammals of the Atewa Range Forest Reserve, Ghana and their conservation status.
Asiakwa South shows clear evidence of excessive hunting from people. There were many spent cartridges and different types of wire snares for trapping. This site is also rich in non-timber forest products (NTFPs) and there is evidence of high levels of chewing stick, sponge and cane harvesting from this site. There are no signs of previous farming activities here, however, there were signs of the area having been subject to mineral prospecting in the past.
Asiakwa North is probably the best refuge for large mammals in Atewa. This is revealed in the high number of species seen there. Notwithstanding the promising nature of this site it shows evidence of excessive hunting by local people. A high number of snares, spent cartridges and hunting trails were seen in this site. The hills at this site also serve as the source of many rivers and NTFPs are not frequently harvested here though other forms of illegal activities such as hunting with guns and wire snaring are predominant (Table 12.2).
On the whole, most of the species that were recorded during the RAP survey are those that can be hunted under the Ghana Wildlife Conservation Regulation, LI 685. However four species, Long-tailed pangolin (Uromanis tetradactyla), African civet (Civettictis civetta), African palm civet (Nandinia binotata), and Yellow-backed duiker (Cephalophus silvicultor) are species that are listed under Schedule I of the Ghana Wildlife Conservation Regulation and thus are wholly protected in Ghana. In terms of species of global conservation concern, Pel's flying squirrel (Anomalurus pelii) is listed as Near Threatened, Yellow-backed duiker (Cephalophus silvicultor), Black duiker (Cephalophus niger), Bay duiker (Cephalophus dorsalis), Maxwell's duiker (Cephalophus maxwellii) and Royal antelope (Neotragus pygmaeus) are listed as Lower Risk/Near Threatened, and West palm squirrel (Epixerus ebii) is listed as Data Deficient under the IUCN categorization of threatened species of the world (IUCN 2006).
CONSERVATION RECOMMENDATIONS
Evidence of more mammal species was found in Asiakwa South and North compared to Atiwiredu. However, Asiakwa North showed a higher level of illegal activities. It is important to address this situation through various conservation education programs and the introduction of alternative/additional livelihood ventures after a detailed socioeconomic survey has been undertaken.
Table 12.2: Illegal activities recorded in the Atewa Range Forest Reserve during the RAP survey.
Mining and other exploitative development not only results in (at least temporary) deforestation, but also increases access to otherwise intact or undisturbed ecosystems. This was confirmed during the surveys through the many illegal activities observed, particularly along access roads and trails developed for exploration. One mining company worker was even seen carrying a shotgun. It is therefore essential that access to forest resources be monitored.
This RAP survey was conducted during the rainy season when Mapania bakdwinii and Leptapisi cochleata form a carpet covering much of the forest floor making footprints, dung and other signs of animals difficult to see. Undertaking a similar survey during the dry season and sampling additional areas, especially towards the periphery of the reserve would most likely increase the number of mammal species directly or indirectly encountered, thus adding to our species list for the reserve.
Finally, monitoring the effects of forest management regimes on wild animal populations requires that periodic biological surveys be carried out to assess the impact of such forest management regimes on our forest fauna.
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During 11 days of field work (25 August – 4 September 2006) in Ajenjua Bepo and Mamang River forest reserves, 137 bird species were recorded, 121 at the former and 115 at the latter site. Only one species of conservation concern was found, Green-tailed Bristlebill Bleda eximius, classified as Vulnerable. Additionally, the Near Threatened Grey Parrot Psittacus erithacus was recorded from the Ajenjua Bepo site. Two of the 11 species restricted to the Upper Guinea forests Endemic Bird Area and 91 of the 180 Guinea-Congo forests biome species known from Ghana were observed during the study.
INTRODUCTION
Birds have been proven to be useful indicators of biological diversity of a site, because they occur in most habitats on land throughout the world and are sensitive to environmental change. Their taxonomy and global geographical distribution are relatively well known in comparison to other taxa (ICBP 1992). The conservation status of most species has been reasonably well assessed and is being regularly updated (BirdLife International 2000, 2004). This permits rapid analysis of the results of an ornithological study and the presentation of conservation recommendations. Birds are also among the most charismatic species, which can facilitate the acceptance of the necessity to implement protective measures by policy makers and stakeholders.
As West African forests are rapidly disappearing, the survival of the birds of the Upper Guinea forests is becoming increasingly dependent on ever fewer areas. Despite a number of field studies conducted in the region in recent years (e.g. Demey and Rainey 2004, 2005; Rainey and Asamoah 2005), the avifaunas of the majority of these forests remain inadequately known.
Ajenjua Bepo Forest Reserve theoretically covers an area of 5.69 km² of moist semi-deciduous forest and consists of both flat and hilly terrain at c. 150–350 m a.s.l. The forest has been severely fragmented by encroaching cultivation of cocoa, banana and cassava, with small patches of the original forest remaining only on the steepest and most rocky hill sides. Even these remnant patches have been degraded, by illegal wood cutting. The forest canopy is open and contains many large gaps, with larger trees reaching up to 40–50 m emerging above a sub-canopy of 10–20 m height. A few small streams occur, but these were entirely dry during our visit.
Mamang River Forest Reserve also consists of moist semi-deciduous forest of similar aspect, but the terrain is mostly flat. However, the area is much larger than Ajenjua Bepo and theoretically covers 53 km², although encroaching cultivation is threatening from all sides. The remaining forest nevertheless appears less fragmented than at Ajenjua Bepo. Similarly to that site, the forest canopy is very open and presents numerous large gaps, with emergents reaching up to 40–50 m. In some places, the sub-canopy of 10–20 m height is closed. Dense tangles of lianas are a characteristic feature of this forest. The few small streams were entirely dry at the time of our study.
No ornithological studies had been conducted previously in Ajenjua Bepo or Mamang River. We carried out 11 days of field work, five at Ajenjua Bepo, from 25 through 29 August 2006, and six at Mamang River, from 30 August through 4 September, during which we recorded 137 of the c. 735 bird species now known from Ghana (Appendix 7). Camps were established at N 06° 22′ 2.3″, W 01°01′ 58.6″ and N 06° 15′ 0.2″, W 01° 02′ 25.7″. Most of our field work was done in the forest proper, although cultivated areas and degraded habitats were also visited, as these form a substantial part of both sites, especially of the first, and were impossible to avoid.
The weather was mainly overcast with some, usually rather short, sunny spells. Rain was frequent at night and occasionally also during the day, especially at the second site.
METHODS
The principal method used during this study consisted of observing birds by walking slowly along tracks. Notes were taken on both visual observations and bird vocalizations. Some tape-recordings were made for later deposition in sound archives. Field work was carried out from dawn (usually 05:45) until 13:00–14:00, and in the afternoon from 15:00–16:00 until sunset (around 18:15). Some species were recorded opportunistically during the night.
For each field day a list was compiled of all the species that were recorded. Numbers of individuals or flocks were noted, as well as basic information on the habitat in which the birds were observed. As many species had finished breeding (several dependent and independent juveniles were noticed), many birds were not singing and several thus must have remained unnoticed. Therefore, no indices of abundance based on the encounter rate are given, as these could convey an erroneous impression on each species' relative abundance.
For the purposes of standardization, we have followed the nomenclature, taxonomy and sequence of Borrow and Demey (2001, 2004).
RESULTS
Ajenjua Bepo Forest Reserve
At this site, 121 species were recorded; these are listed in Appendix 7, along with threat status, endemism to the Upper Guinea forest block, membership of the Guinea-Congo forests biome assemblage, and habitat. No species of global conservation concern were observed. Only one of the 11 restricted-range species, i.e. species which have a global breeding range of less than 50,000 km², that make up the Upper Guinea forests Endemic Bird Area, was found: Sharpe's Apalis Apalis sharpii. Of the 180 Guinea-Congo forests biome species now recorded in Ghana (Fishpool and Evans 2001, Stattersfield et al. 1998), 79 were noted during the survey. The presence of Fiery-breasted Bush-shrike Malaconotus cruentus, a scarce species in Ghana, is worth mentioning.
Mamang River Forest Reserve
In total, 115 species were recorded here (Appendix 7). One species of global conservation concern was observed: Green-tailed Bristlebill Bleda eximius, classified as Vulnerable, indicating that the species faces a high risk of extinction in the medium-term future (BirdLife International 2000, 2004). Two of the 11 restricted-range species that make up the Upper Guinea forests Endemic Bird Area recorded in Ghana were found: Green-tailed Bristlebill and Sharpe's Apalis Apalis sharpii. Of the 180 Guinea-Congo forests biome species known from the country (Fishpool and Evans 2001, Stattersfield et al. 1998), 78 were recorded during the study.
Notes on species of particular interest
Status in West Africa from Borrow and Demey (2001) and in Ghana from Grimes (1987) and Ntiamoa-Baidu et al. (2001).
• Poicephalus gulielmi Red-fronted Parrot
Recorded daily at both sites, with up to 12 around the camp at Ajenjua Bepo. This species is generally scarce in West Africa.
• Bleda eximius Green-tailed Bristlebill
Two singing individuals were recorded at Mamang River; both were with a mixed-species flock. This threatened Upper Guinea endemic is rare in Ghana and reaches the eastern limit of its distribution in Atewa Range Forest Reserve, c. 120 km to the east.
• Alethe diademata White-tailed (Fire-crested) Alethe
Two juveniles were observed together at Ajenjua Bepo on 29 August.
• Apalis sharpii Sharpe's Apalis
This Upper Guinea forests biome endemic was found to be relatively common and vocal in the canopy and sub-canopy, with daily observations of up to two singing individuals at Ajenjua Bepo and up to five at Mamang River.
• Muscicapa epulata Little Grey Flycatcher
A single individual catching insects in flight was seen at the forest edge near camp at Ajenjua Bepo. This small species is generally scarce in West Africa.
• Parus funereus Dusky Tit
A single, vocal individual was found in a very degraded part of Ajenjua Bepo. It is scarce to rare and local in West Africa.
• Malaconotus cruentus Fiery-breasted Bush-shrike
Two single individuals were heard singing at different locations at Ajenjua Bepo. This species is generally rare and local in West Africa; in Ghana it is known from only one Important Bird Area (Atewa).
DISCUSSION
Ajenjua Bepo and Mamang River were found to have genuine forest species, as well as species typical of forest edge, farm bush and cultivation. Although only one species of conservation concern was found, the number of forest-restricted species was still relatively high, especially considering the often poor condition of the forest, in particular at Ajenjua Bepo. An even higher species number could have been reached if the survey had been conducted during a different season, for example in February-March, when more species are vocally active and, additionally, Palearctic migrants are still present.
The very low number of diurnal forest raptors on our list is remarkable. African Goshawks Accipiter tachiro were silent and only two were seen hunting at Ajenjua Bepo; African Harrier Hawks Polyboroides typus were recorded once at each site, one at the former and two together at the latter.
Only two hornbill species were found: Pied Tockus fasciatus (still common, with up to 12 in a day) and White-crested Tropicranus albocristatus (up to at least four in a day). The absence of large hornbills and also of Great Blue Turacos Corythaeola cristata, both conspicuous species in good forest, are indicative of the condition of the forest and the high hunting pressure.
Although mixed-species flocks were regularly encountered, they were not particularly common and comprised a relatively small number of individuals. Typical members of these flocks included Red-tailed Bristlebill Bleda syndactylus, Grey-headed Bristlebill B. canicapillus, Western Bearded Greenbul Criniger barbatus, Red-tailed Greenbul C. calurus, Icterine Greenbul Phyllastrephus icterinus (remarkably discreet and not numerous), Green Hylia Hylia prasina, Blue-headed Crested Flycatcher Trochocercus nitens, Red-bellied Paradise Flycatcher Terpsiphone rufiventer, Chestnut Wattle-eye Dyaphorophyia castanea, Fraser's Sunbird Deleornis fraseri, Blue-throated Brown Sunbird Cyanomitra cyanolaema, Black-headed Oriolus brachyrhynchus or Black-winged Oriole O. nigripennis, Velvet-mantled Drongo Dicrurus modestus, and one to three Malimbus species (Crested M. malimbicus, Blue-billed M. nitens and/or Red-headed Malimbe M. rubricollis). Other species observed in these flocks comprise Narina's Trogon Apaloderma narina, Buff-spotted Woodpecker Campethera nivosa, Brown-eared Woodpecker C. caroli, Purple-throated Cuckoo-shrike Campephaga quiscalina, Blue Cuckoo-shrike Coracina azurea, Finsch's Flycatcher Thrush Stizorhina finschi, Sharpe's Apalis Apalis sharpii, Grey Longbill Macrosphenus concolor, Rufous-crowned Eremomela Eremomela badiceps, Fraser's Forest Flycatcher Fraseria ocreata, Chestnut-capped Flycatcher Erythrocercus mccallii, Sabine's Puffback Dryoscopus sabini, Red-billed Helmet-shrike Prionops caniceps, Grey-headed Negrofinch Nigrita canicapillus and Chestnut-breasted Negrofinch N. bicolor. No Shining Drongo Dicrurus atripennis was recorded.
The generally rare and local Fiery-breasted Bush-shrike Malaconotus cruentus was found at Ajenjua Bepo. Other species occurring in the reserves that are rare in Ghana and generally uncommon in their global range include Little Grey Flycatcher Muscicapa epulata, Dusky Tit Parus funereus and Johanna's Sunbird Cinnyris johannae.
CONSERVATION RECOMMENDATIONS
Although neither Ajenjua Bepo nor Mamang River appear to have particularly remarkable birds, they still harbour a significant selection of Guinea-Congo forests biome species. Forests like these are becoming increasingly rare in West Africa. Considering the very fragmented state of Ajenjua Bepo, it appears preferable to concentrate conservation efforts on Mamang River, which is much larger and less fragmented. The conservation of the latter, as it presently is, would be sufficient for the preservation of the globally threathened Green-tailed Bristlebill.
Hunting should be curtailed. Although it currently mainly targets mammals, certain large bird species, such as Crested Guineafowl, Great Blue Turaco and large hornbills, also fall victim to these illegal practices, which could explain their absence.
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Appendices
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Sixty-one species of Tettigoniidae were collected, the highest number of katydids known from a single location anywhere in Africa. Of these, at least 8 are new to science, and 36 are new to Ghana. Site 2 (Asiakwa South) showed the highest species richness (50 spp.), likely due to a high edge effect created by a dense network of roads. While we recommend this area be protected in its entirety, any future development that is allowed within the area should be restricted to the southern part of the range in order to reduce further fragmentation of the remaining forest. Furthermore, roads and clearings that are no longer in use should be reforested to reduce habitat fragmentation and to discourage illegal logging and hunting.
INTRODUCTION
Katydids (Orthoptera: Tettigonioidea) have long been recognized as organisms with a significant potential for their use in conservation practice. Many katydid species exhibit strong microhabitat fidelity, low dispersal abilities (Rentz 1993a), and high sensitivity to habitat fragmentation (Kindvall and Ahlen 1992) thus making them good indicators of habitat disturbance. These insects also play a major role in many terrestrial ecosystems as herbivores and predators (Rentz 1996). They are themselves a principal prey item for several groups of invertebrates and vertebrates, including birds, bats (Belwood 1990), and primates (Nickle and Heymann 1996). At the same time many species of katydids are threatened, and some appear to have already gone extinct (Rentz 1977).
The conservation value of katydids has been recognized in Australia (Rentz 1993b) and Europe, leading to the development of captive breeding programs (Pearce-Kelly et al. 1998), listings on individual country (Glowacinski and Nowacki 2006) and global Red Lists (IUCN 2006), and introduction of regulations aimed at their conservation. But their use as conservation tools or targets of conservation actions in tropical regions, where their importance and the level of endangerment are the highest, is hampered by the lack of baseline data on katydid distribution as well as the shortage of katydid expertise and identification tools, a phenomenon known as the taxonomic impediment. It is therefore critically important that more effort be directed towards basic faunal surveys of katydids across the tropics, thus creating the basis on which a successful conservation strategy for these animals can be built. Such surveys, if conducted in pristine or relatively undisturbed areas, also provide reference data, which can later be used in habitat monitoring or restoration efforts that should follow any industrial or agricultural activity. West African ecosystems are in particular need of extensive biotic surveys, as these are some of the least studied tropical habitats while also being subject to widespread, poorly regulated, and often illegal logging and mining activities, combined with persisting slash-and-burn agricultural practices. This results in a rapid decline of available, natural habitats, and thus an inevitable loss of biodiversity.
The following report presents the results of a survey of katydids conducted between June 6 – 24, 2006 at selected sites within the Atewa Range Forest Reserve (Atewa) in the Eastern Region of Ghana. This is the first systematic survey of katydids in this country, and its results indicate the presence of a rich and unique fauna of this group of insects. To date, the only records of katydids in Ghana are those in the works of Beier (1965), Bolívar (1886, 1890, 1906), Karsch (1888, 1890), Ragge (1962, 1980), and Redtenbacher (1891) who collectively recorded only 13 species of katydids from this country.
From both floristic and faunistic points of view, the Atewa Range is a particularly interesting area. Located in the Akyem Abuakwa Traditional Area, the reserve comprises two blocks of the Upland Evergreen Forest, one of only two such forest ecosystems in Ghana. The reserve contains about 60% of the forest coverage within the entire Eastern Region, and thus most of the available habitats for its forest fauna. The area included within the confines of the reserve spans two floristic zones, with the larger, northern portion of the reserve covered with a moist deciduous forest. Most of the reserve is situated on two plateaus, ranging in elevation from 350 to 800 m above sea level. This topography contributes to climatic conditions that favor plant formations that require constant, high humidity, and somewhat lower temperatures than floras in the surrounding, lowland areas. Consequently, the insect faunas of the Atewa Range can be expected to differ from lower areas of Akyem Abukawa.
METHODS
During the survey three methods were employed for collecting katydids: (1) collecting at incandescent and ultraviolet (UV) lights at night, (2) visual search at night, and (3) net sweeping of the understory vegetation during the day and at night. Unfortunately, the UV light method was not available at all study sites, thus potentially reducing the chance to collect flying, nocturnal species, such as many members of the Phaneropteridae. However, the availability of other light sources (incandescent lights around the camp) allowed us to collect many of the nocturnal, flying species of katydids, including several inhabitants of the upper layers of the forest canopy.
Net sweeping was employed in the vegetation along the roads within the forest, the forest understory, and natural openings within the forest, such as edges of streams or forest ponds. This method was highly effective in locating seed-feeding katydids in tall grasses as well as a number of arboreal katydids that cling upside-down to the lower surface of leaves. Sweeping was standardized by performing five consecutive sweeps in a series before the contents of the net were inspected. By far the most effective method of collecting, both in terms of the number of species collected and number of collected specimens, was the visual search at night. Most of the collecting was conducted after dark, between the hours of 8 pm and 2 am when the activity of virtually all katydid species is the highest. Yet day collecting along the forest roads also yielded several interesting species, including one (Ruspolia sp. 1), the presence of which may indicate an encroachment of savanna elements into the reserve.
In addition to physical collection of specimens, stridulation of acoustic species was recorded using the Sony MZ-NHF 800 digital recorder and a Sennheiser shotgun microphone. These recordings are essential to establish the identity of potentially cryptic species, for which morphological characters alone are not sufficient for species identification. An ultrasound detector Pettersson D 200 was also used to locate species that produce calls in the ultrasonic range, undetectable to the human ear.
Representatives of all encountered species were collected and voucher specimens were preserved in 95% alcohol and as pinned, dry specimens. These specimens will be deposited in the collections of the Museum of Comparative Zoology, Harvard University and the Academy of Natural Sciences of Philadelphia (the latter will also become the official repository of the holotypes of several new species encountered during the present survey upon their formal description).
Katydids were surveyed at three sites within the reserve, Site 1 in the southern, and Sites 2 and 3 in the northern part of the range. Site 1 (Atiwiredu) was located at 6°12′24.7″N, 0°34′37.2″W, elevation 795 m, and sampling was conducted there from 6 - 10 June, 2006. This site had an extensive network of roads, and was subject to prospecting activity by ALCOA. Despite this activity, the forest condition was rated 2 by the botanical team, indicating a relatively low level of disturbance.
Site 2 (Asiakwa South) was situated at 6°15′44.3″N, 0°33′18.8″W, at the elevation of 690 m, and sampling was conducted there from 11 - 16 June, 2006. This site, while not currently subject to prospecting activity, still contained an extensive network of roads, some overgrown with tall grasses. These roads appear to act as passages allowing the penetration of invasive elements, such as grasses or species of insects normally associated with open habitats, deep into the forest. The condition of the forest at this site was rated as 3.
Site 3 (Asiakwa North) was located at 6°16′16.4″N, 0°33′52.8″W, elevation 769 m, and was sampled from 16 - 24 June, 2006. Most of the site was covered with tall, closed-canopy forest, with little underbrush, and no open roads. Its condition was rated as 2. There were few gaps in the forest, which accounts for the low number of species associated with such habitats. The only gaps present were overgrown with tall, broad-leaved plants of the family Marantaceae.
RESULTS
The survey resulted in the collection of 61 species of katydids, the highest number of katydids known from a single location anywhere in Africa. Most collected species represent new records for Ghana, and at least eight species are new to science (but it is quite likely that more species will be determined to be new once the process of their identification is completed.) Identities of several species require confirmation by comparing them to type specimens of species described from West Africa as in some cases the original descriptions are not detailed enough to make positive identification. Many species listed here appear to have a wide, West African distribution, having been recorded from sites in Cameroon and Guinea. Their presence in eastern Ghana supports this notion, and fills a gap in our knowledge of West African biogeography. A full list of recorded taxa is given in Table 7.1, and below I comment only on new or particularly interesting species.
Family Phaneropteridae
This group of katydids includes most species restricted to thecanopy level of the forest. Many are excellent fliers, and can be collected at night using UV or incandescent lights. Some are diurnal and can be heard calling during the day from tall trees. All members of this family are exclusively herbivorous. Twenty-seven species of this family were found during this survey.
Ducetia fuscopunctata Chopard, 1954 — this species was originally described from Mt. Nimba, Guinea, and this is its first record from Ghana. It is associated with edge habitats, such as tall vegetation along the roads, but in can also be found in natural gaps within the forest. This species was particularly abundant at Site 2, but was conspicuously absent from Site 3.
Arantia spp. — Six species of this genus were recorded, at least two of which are possibly new to science. They were all associated with tall understory vegetation within the forest as well as tall, broad-leaved plants along the roads. A. rectifolia Br.-Watt, A. retinervis Chopard, and A. angustipennis Chopard are new to Ghana, having been previously recorded only from Fernando Po, Cameroon, and Guinea, respectively.
Preussia lobatipes Karsch, 1890 — This spectacular leaf mimic has been known so far only from a handful of specimens collected in Cameroon and Guinea, and its presence in Ghana is not surprising. A single female was collected at lights at Site 2.
Weissenbornia praestantissima Karsch, 1888 — Like the previous species, W. praestantissima has previously been known only from Cameroon and Guinea. Two individuals were collected at lights at Site 2.
Plangiopsis foraminata Karsch — Two individuals of this arboreal, lichen-mimicking katydids were collected at lights at night at Site 2. Previously this species has only been known from Cameroon (Karsch 1891).
Family Conocephalidae
The Conocephalidae, or the conehead katydids, include a wide range of species found in both open, grassy habitats, and high in the forest canopy. Many species are obligate graminivores (grass feeders), while others are strictly predaceaous. A number of species are diurnal, or exhibit both diurnal and nocturnal patterns of activity. Only three species of this family were recorded.
Conocephalus carbonarius Redtenbacher, 1891 — This species is one of the few true forest species of the genus. In-dividuals of C. carbonarius were common in the understory of forests at all visited sites, but were particularly abundant along roads and in herbaceous vegetation along the edges of bodies of water. Unlike most species of the genus Conocephalus, males of C. carbonarius are active both day and night, singing from vegetation very low to the ground. This species appears to be predominantly predaceous. It was originally described from Ghana (Redtenbacher 1891), and was subsequently found in Guinea (Chopard 1954).
Ruspolia sp. 1 — A single individual of this predominantly savanna genus was found at Site 2 in grasses along one of the roads. Ruspolia species are obligate graminivores, and can only survive in habitats rich in grasses, and where humidity is not very high. The presence of a Ruspolia species deep within the forest is a sign of potentially negative changes within this environment, and points to the important role roads play in allowing foreign elements to penetrate forested areas.
Thyridorhoptrum sp. 1 — A new species of this genus was found at Site 2. It appears to be related to T. baileyi Pitkin from forests of Uganda, but differs in a number of characters, including the call pattern of the males.
Family Meconematidae
This poorly studied family includes some of the smallest species of katydids, and many appear to be exclusively predaceous. Nearly all species of Meconematidae are arboreal, nocturnal, and extremely agile, making it very difficult to collect them (many are flightless, and thus rarely come to lights at night.) Ten species were recorded, including at least two representing a new genus and new species.
Amyttosa mutillata (Karsch, 1890) — A species known previously only from Cameroon (Karsch 1890). It was also erroneously recorded from Equatorial Guinea (Beier 1965), a mistake based on the false assumption that the original type specimens of A. mutillata possessed damaged female reproductive organs (hence the name), and that similar but “undamaged” individuals from other parts of Africa were conspecific. Yet numerous individuals collected at Sites 2 and 3 during the current survey prove conclusively that this species is unique in having a highly reduced, rudimentary ovipositor, a condition extremely rare within this group of katydids, and usually associated with egg laying on exposed surfaces, such as leaves or bark. Such a behavior is found in katydids living in highly humid environments.
Gen. nov. spp. — Two species of a new genus of flightless Meconematidae were found at Sites 2 and 3. They appear to be closely related to a yet undescribed genus of katydids from the Upper Guinean forest of Guinea, and may turn out to be congeneric. Because these new species appear to have poor dispersal abilities, typical of most flightless katydids, it is possible that they may be endemic to the Atewa Range.
Family Mecopodidae
Three species of this exclusively tropical group of katydids were found during this survey. Most of its species are associated with humid forests, and all species appear to be herbivorous. No members of this family have ever been recorded from Ghana, although their presence there is not surprising as they are known from most of the neighboring countries.
Afromecopoda spp. — Two species of this genus were collected, and one appears to represent a species new to science. A. frontalis (Walker) was found to be common at all three sites. Members of this genus are some of the few West African katydids associated with leaf litter and the bottom of evergreen and deciduous forests.
Table 7.1. A check list of species of katydids recorded from the Atewa Range Forest Reserve, Eastern Ghana.
Corycoides abruptus (Krauss, 1890) — This interesting species is known only from the holotype from an unknown locality and a handful of specimens collected in Guinea (Chopard 1954). This is the first record from Ghana.
Family Pseudophyllidae
Virtually all members of tropical Pseudophyllidae can be found only in forested, undisturbed habitats, and thus have a potential as indicators of habitat changes. These katydids are mostly herbivorous, although opportunistic carnivory was observed in some species. Many are confined to the upper layers of the forest canopy, and never come to lights, making it difficult to collect them. Fortunately, many of such species have very loud, distinctive calls, and it is possible to document their presence based on their calls alone, a technique known well to ornithologists. At least 18 species of this family were collected during the present survey.
Adapantus nitens (Chopard, 1954) — Originally described from N'Zo (Mt. Nimba), this is only the third record of this species, and the first outside of Guinea. These katydids were common at all three sites.
Adenes spp. — Three species of this flightless genus were found during this survey, at least one of which appears to be new to science (a comparison with the type specimens of the already described species is required before the final decision of its new status can be made).
Lichenochrus and Polyglochin — Two species of these interesting, lichen-mimicking genera were found: L. congicus Rehn and P. peculiaris Karsch. Both are new to Ghana. Like most lichen-mimicking katydids, these insects may be restricted to small patches of humid, higher elevation forests that can support a wide variety of the lichens these katydids feed upon.
DISCUSSION
Despite a relatively very short period of time spent surveying katydids within the ARFR, this study increased the number of species known from Ghana by over 500%. This does not necessarily indicate the uniqueness or particular richness of the area's insect fauna, but clearly demonstrates the lack of baseline data on the distribution of katydids (and most likely other invertebrates) in this country. Such data are critically important as a reference for future habitat restoration projects, and may also help pinpoint populations of particularly endangered or threatened species where an immediate conservation action is required.
Within the ARFR we found a remarkable species richness of katydids, and a very high number of new and potentially endemic species. Despite ongoing bauxite prospecting activity, the forest of the reserve still appears fairly intact, and harbors the highest number of katydids known from any single location in Africa. Thus, every effort should be made to minimize the impact any future development may inflict on the forest reserve. Of the three sites within the reserve, the highest number of species was found at Site 2 (Asiakwa South). In comparison to Sites 1 and 3, which appeared to have fewer roads and less open, easily accessible habitat, Site 2 shows the most pronounced edge effect. Because Sites 2 and 3 are both located within the northern part of the range (the northern plateau), and this part constitutes a larger, continuous swath of the forest than the southern plateau, conservation of the northern portion of the reserve should receive a higher priority. If any development is planned within the reserve, it is strongly recommended that such activity be limited to the southern part of the range, thus reducing the fragmentation of the already severely restricted forest, and the loss of species that require large, continuous areas of a forest habitat. Landscape- or habitat-altering development within this robust and intact ecosystem will not only damage, perhaps irreparably, the original forested habitats, but will also open them to other destructive activities, such as illegal logging or hunting, by creating access points and inroads. The negative effects of a dense network of prospecting roads within the Atewa Range are already evident through the loss of virtually all tall, emergent trees, and the rampant bushmeat hunting activity. In addition, wide roads entering the forest allow invasive elements, such as grasses or savanna insects to penetrate into this environment. They also contribute to fragmentation, higher light penetration, and ultimately a decrease in forest humidity, which may lead to the loss of species requiring shady and humid conditions. Thus, in addition to restricting any potential exploration activities to the southern part of the range, it is strongly recommended that any roads or exploratory clearings within the forest that are no longer in use be reforested with the same tree species that were present prior to prospecting activities.
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