The state of biodiversity in Ghana : Knowledge gaps and prioritization

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.


INTRODUCTION
Biodiversity loss and conservation have been a global focus for at least two decades, mainly addressing issues of prioritization for efficient fund allocation (Myers et al., 2000;Mace et al., 2000;O'Connor et al., 2003;Brooks et al., 2006).At the national and local levels where all biodiversity driving forces converge, and where conservation needs to be implemented, prioritization is often biased by parochialism due to poor data availability (Hunter and Hutchinson, 1994;da Fonseca et al., 2000).Over the past century, different human activities especially in agriculture have degraded Ghana's biological resources significantly.Exactly 80 years ago, 63% of the country's forests were in pristine or near-pristine condition in the forest zone (Dickson, 1969).Today, the landscape is mostly human-dominated with forest patches covering ~15% of the country's land area.This is mainly due to land conversion to agriculture, a phenomenon which may continue to biodiversity losses until the economy grows and becomes less dependent on agriculture (Beier et al., 2002).This trend can however be reversed, or at least stabilized, under land-use management regimes in which crop production is maximized with no significant losses to E-mail: kaupong@gmail.com.Tel: +8618811583917.
Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License biodiversity (Tscharntke et al., 2012).Essentially, every efficient management plan is driven by quality agro-ecological data, and should gravitate towards increasing ecological complexity through the cultivation of multiple resource-efficient crop varieties under enhanced fertilization while allowing some less-competitive native flora (Kumaraswamy and Kunte, 2013).
Like other African countries (da Fonseca et al., 2000), Ghana lacks location and landscape-scale ecological data, a setback to biodiversity conservation.The currently available biodiversity information has been described as scanty with inaccuracies and gaps, and lacking up-todate knowledge (Ministry of Environment and Science, 2002;Ghana Report, 2009).Fortunately, a large collection of species occurrence data exists in different museums and online databases (see sources of information).This can be synthesized, together with data and results from recent studies, to obtain the baseline information needed to promote the development of new, effective strategies necessary for the conservation and sustainable use of the country's biological resources (da Fonseca et al., 2000).The objectives of this study were to: (i) compile relevant occurrence records of species, and together with recently published data, synthesize them to provide a current view of biodiversity, (ii) map the distribution of protected and non-protected areas previously studied, along with their corresponding studied taxa, for directing future studies, and (iii) identifying and discussing existing knowledge gaps.

Study area
Ghana is located in West Africa (4.7° -11.2°N, 3.3°W -1.2°E), with its southern part lying on the coast of the northeast Atlantic Ocean (Gulf of Guinea) (Figure 1).To the north is Burkina Faso, to the west is Côte d'Ivoire and to the east is Togo.The country extends over two unique ecosystem zones; Eastern Guinean Forests and West Sudanian Savanna, with a transitional Guinean Forest-Savanna Mosaic ecosystem zone.It encompasses a total land area of 238,761 km 2 , and has an annual bimodal rainfall distribution between 900 and 2,100 mm (Ntiamoa-Baidu et al., 2001).The current population is 24,658,823 (2010 estimate) with an annual population growth rate of 2.5% (Ghana Statistical Service, 2013).Divided into 10 regions, the country has ~15% of land under protection, the largest of which is in the Western Region where 32.3% of land is protected (Table 2 in Supplementary Information -Tables 1-3).

Sources of information
Species data totaling 296 (Table 1) was obtained from 73 peerreviewed literature and several databases.The SCI-Web of Science was consulted for data on Ghana's biodiversity in November 2013.A search for Ghana species occurrence data was also conducted in large species databases like the Global Biodiversity Information Facility (GBIF) on Ghana, comprising 90 different organizations, AVIBASE (Lepage 2014), African Bird Club (Dowsett et al., 2014), Amphibia Web (University of California, Berkeley), The Reptile Database (Uetz and Hošek 2014), African Butterfly Database (Sáfián et al., 2009), Afromoth (De Prins andDe Prins, 2014), Orthoptera Species File (Eades et al., 2014) and the IUCN's Red List of Threatened Species.Finally, web pages of researchers working on different aspects of the country's biodiversity were visited for published literature containing additional information.Diversity data (species richness) and study locations were recorded for six taxonomic groups (birds, insects, mammals, amphibians, reptiles and plants) in three habitat systems: protected areas (forest and wildlife reserves, etc.), non-protected areas and sacred groves (Table 1; Table 1 in Supplementary Information -Tables 1-3) (Aalangdong, 2009;Ryan and Attuquayefio, 2000).Each article included in this review reported species richness of particular taxa for at least one site.In cases where different articles on the same location reported different species richness values for the same taxa, the maximum was used.Species lists were compiled from the records obtained fSurom the databases and literature.

Data analysis
Box and whisker plotting were used to indicate differences in species richness across different habitat types for each taxonomic group.In addition, a combined map of the spatial distribution of sites where recent (1994 -2013) taxonomic studies have been undertaken was generated for visual assessment of the present knowledge and possible gaps.

Birds
A total of 794 bird species belonging to 101 families have been recorded, of which 494 (65%) are resident, and 16 species (14 of which are resident) are globally endangered (Table 2; Supplementary Information -Birds).The Mole National Park, probably due to its large size, has the highest bird species richness of 314 (Ntiamoa-Baidu et al., 2001), while the Afrensu Brohuma Forest Reserve has the lowest richness of 44 species (Manu 2011).Table 2 shows the regional distribution of bird species in Ghana.A summary of the distribution of bird species richness for protected and non-protected areas of the country is presented graphically in Figure 2.
Studies on birds, like other species, have concentrated more on the protected areas (87.5%), with little attention to non-protected areas (11.25%) and sacred groves (1.25%) (Table 1).The Brong-Ahafo Region, with only one Important Bird Area (IBA) of ~1,830 km 2 has the highest bird species richness (533), while the Western Region with 18 of the 36 IBAs (total area ~3,850 km 2 ) in the country, has a richness of 495 (Ntiamoa-Baidu et al., 2001;Table 2).This is surprising considering the fact that the Western Region occupies the largest portion of the richest biodiversity area of the country (Myers et al., 2000;Ministry of Environment and Science, 2002).Beier et al. (2002) gives strong evidence of a positive correlation between habitat size and species richness of birds, which offers some explanation on the basis of island biogeography.Moreover, the low diversity of birds in the      Western Region could suggests that, despite birds being the best studied taxa in terms of spatial coverage, the present knowledge on their diversity, distribution and abundance is still insufficient (Weckstein et al., 2009).Despite the small sizes of the sacred groves, they may conserve small populations of forest-specialist without local extinction threats because, unlike butterflies (Larsen et al., 2009), birds from nearby source habitats can recolonize them.Attuquayefio (2008) found no species common to all five forest reserves in the Brong-Ahafo Region.This may suggest that (i) each forest-specialist bird species has a strict set of habitat requirements, and (ii) those forest reserves have different ecological conditions probably related to the different degrees of degradation within them.Details of the distribution of forest and savanna restricted species in the IBAs is given elsewhere (Ntiamoa-Baidu et al., 2001).
Using the habitat distribution ratios obtained from Larsen (2006), the number of forest-centered, savannacentered and ubiquitous butterfly species are estimated at 798, 177 and 39, respectively.Table 3 shows the distribution of butterflies in different vegetation types and rainfall bands.About 20% of the butterfly species, including 16 endemics, are located within the human dominated areas and have not yet been recorded in the protected areas (Larsen, 2006).These species, unless they are ubiquitous, need conservation attention regardless of their endemic status.This is because land-use activities such as bush burning and insecticide application can potentially cause local extinctions due to their low mobility, especially if they are restricted to small geographic areas.For example, even though rare, all the three species (Abisara intermedia, Abisara tantalus and Abisara gerontes) of the Riodinidae, were recorded only in non-protected areas (Larsen, 2006).
More than three-quarters of Ghana's butterfly fauna is located within the forest zone, which stretches from the southwest to the mid-regions (Larsen, 2006).Concentration is unusually high in the southwest wet forests in the Western Region, upland moist forests within the Atewa-Range Forest Reserve and the forest areas of the Volta region (Emmel and Larsen, 1997).For example, even though the Atewa Range Forest Reserve covers only an area of ~232 km the butterfly species richness of Western Europe, and more than the butterfly richness of any state in the USA (Larsen, 2005).This suggests that land-use activities that promote the encroachment of savanna vegetation into the forest zone can potentially cause the loss of many savanna-hostile butterfly species.Both vegetation and rainfall are known to affect butterfly richness with an approximately linear relationship (Larsen, 1994).Thus, any long-term perturbations, distributional shifts, and declines in rainfall may lead to loss of biodiversity and rapid turn-over of species (Dornelas et al. 2014).
Butterflies are the best studied fauna in the country's sacred groves, with at least 7 sacred groves studied.However, due to Larsen's (2006) estimated habitat area requirement of 200 km 2 for butterfly conservation, the continued local survival of some forest-specialists is doubtful in sacred groves (and even in some forest reserves) because of their small areas.This follows directly from the observation of Larsen et al. (2009) that local extinction of butterfly species in Boabeng-Fiema, an isolated reserve of ~ 4.4 km 2 area, cannot be reversed because there is no opportunity for continued gene-flow through re-colonization from nearby subpopulations, a process which is important for the continued local survival of butterflies than the surface areas of the habitats they occupy.
The total species richness of non-lepidopteran arthropods recorded under nine taxonomic orders is 1,102 (Table 4).The species richness of arthropods belonging to the Coleoptera (382 species from 130 genera) was based on Browne's (1963) estimate.However, 118 species belonging to the Scolytidae and Platypodidae which Browne omitted from his paper are not presented in the species list (Supplementary Information -Insects).Similarly, for Hymenoptera, only 221 of the species richness of 404 reported by Kolo and Hormenyo (2009) are listed.Recent studies (Davis and Philips, 2005;Lachat et al., 2006;Norris et al., 2010;Kolo et al., 2011) have indicated that human land-use has negatively affected non-lepidopteran arthropods in West Africa.Larsen (2005), however, acknowledges that the population of savanna and adventive species has increased significantly within the forest zone, and Belshaw and Bolton (1993) believe that the change may not be significant.

Mammals
Currently, 327 species of terrestrial mammal have been recorded, of which four are endangered, eight are vulnerable and 15 are near threatened (IUCN, 2013; Table 5).Studies on mammals have concentrated primarily on small and medium-sized (or large) mammals with a ratio of about 3:1 (Table 1).Small mammals are the best studied in terms of species distribution and abundance on different land-use systems in the country.Small mammal diversity is high in areas that have stable habitats with dense vegetation, sufficient food availability and increased ground cover (Attuquayefio and Wuver, 2003;Ofori et al., 2013).Jeffrey (1977) also reported that the abundance of small mammals is determined by food availability, while richness is determined by availability of dense ground cover.
Diversity of small mammals has been found to be low in most forest reserves but high in built-up areas and other human dominated land-use systems (Jeffrey, 1977;Vordzogbe et al., 2005).Small mammals confronted by unfavorable food conditions in primary forests with sparse ground cover migrate to adjacent human-disturbed habitats with denser ground covers and sufficient food availability (Vordzogbe et al., 2005).Rainfall, being an agent for ground cover densification and food availability, also causes increases in small mammal diversity (Attuquayefio and Wuver, 2003).This explains why, sometimes, the diversity of small mammals is higher in human dominated land-use systems than in protected areas.The above observations suggest that the abundance and diversity of small mammals are less dependent on level of pristineness of habitats, even though other studies have found the opposite (Ofori et al., 2012).The species richness data available from recent single assessments of both small and large mammals in protected and non-protected areas are shown in Figure 2.
At habitat level, small mammal diversity depends on habitat size, distance from a colonization source, and the presence of suitable migration corridors (Decher, 1997).Hunting is the main cause of biodiversity decline in large and medium-sized mammals (Curry-Lindahl, 1969;Asibey, 1974;Vordogbe et al., 2005), while bush burning is the worst threat to small mammals (Decher and Bahian, 1999;Attuquayefio and Wuver, 2003;Vordzogbe et al., 2005).

Herpetofauna
The terrestrial herpetofaunal richness of the country presently stands at 377 species (Supplementary Information -Amphibians; Supplementary Information -Reptiles) comprising a total of 119 species of amphibians belonging to 13 families (including six endemics), and 259 species of reptiles belonging to 18 families (Tables 6  and 7).Available data on recent, single herpetological assessments of some protected and non-protected areas are presented graphically in Figure 4. Ghana's amphibian diversity is highest in the Western Region of the Country (Rödel et al., 2005).Before the beginning of the 21st century, the highest amphibian richness recorded for a single site was 20 species (Rödel and Adjei, 2003).In recent years, however, higher values have been recorded, the highest being 40 species for the Ankasa Conservation Area (Rödel et al., 2005).The diversity of amphibians correlates negatively with elevation and density of ground litter (Wiafe and Adjei, 2013).Reptiles have also been studied in recent years, and like amphibians, the studies are few and not comprehensive.So far, protected areas studied include Kyabobo National Park (Leaché et al., 2006), Gyemira and Gyeni River Forest Reserves (Yahaya et al., 2013), and Draw River and Krokosua Hills Forest Reserves (Ernst et al., 2005).

Plants
The current total plant species richness of the country is  3).
Occurrence records between 1908 and 1974 indicate that T. gentii, despite being concentrated near Somanya (Eastern Region) and spread along the north-west direction into the Ashanti Region, was recorded in a few other parts of the country.Specifically, in the years 1952, 1960 and 1970, the species was sparsely recorded at different locations within the Guinea Savanna vegetative zone of the country.Also in 1952, T. gentii was recorded near Amisano in the Central Region.By extracting and examining the elevation and slope of each of the 102 sites where T. gentii was observed between 1908 and 1999, it has become clear that the species occurred more at lower and medium elevations ( 300 m AMSL) than at higher elevations.The species occurred on flat and gentle-sloped terrains because 50% of the records were obtained from slopes from 0 to 7°.Recently, it has been reported that T. gentii occurs on high elevations and on rocky slopes (Anyomi et al., 2008), which is possibly due to overexploitation of the species that occurred at lower elevations.Despite earlier reports that the species is geographically restricted to Bandai Hills, Sapawsu and Yongwa Forest Reserves (Anyomi et al., 2008;Boshier et al., 2011), there is a strong indication of its occurrence in the other forest reserves within the area defined by the following coordinates: i. 0.273°E, 6.375°N; ii.0.022°W, 5.744°N; iii.1.362°W, 6.434°N; iv.1.047°W, 7.084°N, especially Dome River, Southern Scarp, Afram Headwaters, Volta River and Bomfoum (Figure 3).
Similarly A. taiensis, known to occur only in Ghana and Côte d'Ivoire, appears to occur within the Eastern Guinean Forest block extending from the Sassandra River (Côte d'Ivoire) to the Volta River.In Ghana, its concentration is within the Atewa Range Forest Reserve area, and spreads towards the wet evergreen forest zone in the Western Region.The historical distribution range of A. taiensis is slightly different from that of T. gentii because it recorded only in the Eastern Guinean Forests ecoregion.The last record of the species was made in the Aiyaola Forest Reserve (0.95°W, 6.15°N) in March 1970 which should be a starting point towards establishing its conservation status.The last critically endangered species, S. fimbrisepala is believed to be endemic to Ghana and Cameroun.In Ghana, only two records of the species have been filed in the University of Ghana Herbarium; one of which was recorded ~1.25 km, 026° from Anhweam in the Western Region in 1935 while the other (date unknown) was recorded near Ahinsan, ~2.5 km, 031° from Dompoase in the Ashanti Region.Unfortunately, both sites occur in human dominated landuse areas; however, search for the existence and conservation status of the species in the nearby Subuma and Bosomtwi Range Forest Reserves respectively could yield some positive results.
For the protected areas, the average species richness of 22 reserves whose data were recorded in recent studies is 306.Single study records on the richness of groups of plants species are presented in Figure 4. Plant   diversity and distribution in the forest zone have been well documented (Thompson, 1910;Hall and Swaine, 1976) even though the studies were carried out several decades ago.In recent years, studies have declined considerably in all vegetative zones.Tree and liana species richness of human-dominated land-use areas decrease with increasing years of continuous human activity (Asase and Tetteh, 2010;Anyomi et al., 2011;Anglaaere et al., 2011;Addo-Fordjour et al., 2012).Secondly, perhaps due to the differences in structure and management, plant species diversity increases from seedling through sapling to tree stages in natural forests, while the reverse is true for agroforestry systems (Addo-Fordjour et al., 2009;Boakye et al., 2012).As a result, undisturbed forests in the country are characterized by high tree diversity, low herb diversity and medium sapling diversity; disturbed (logged) forests are characterized by low tree diversity, high sapling diversity and medium herb diversity; and disturbed-invaded forests are characterized by high herb diversity, low sapling diversity and medium tree diversity (Fordjour et al., 2009).Thirdly, for highly degraded areas undergoing regeneration, plant diversity transitions in time is from grass-dominating through shrub-dominating to tree-dominating (Campbell, 2005).

Study coverage
The dataset on study sites comprises species richness data (mainly from 1994 -2013) on single or multiple taxa covering 146 different locations scattered over the country (Figure 5).Of this number, 88 (~60%) sites are protected areas, 48 sites are off-protected (including wetlands) and 10 sites are sacred groves.With the exception of two sites (Muni-Pomadze Ramsar site and Wli/Agumatsa proposed protected area) which have had multiple taxonomic studies on multiple taxa, the remaining non-protected sites have been studied only once for single taxa.Eight out of 10 sacred groves were solely studied for butterflies, with Okyem and Prako sacred groves being studied for small mammals.While acknowledging that several unpublished studies (for example, student thesis, etc.) may be available, this study reveals that only about 32% of the protected areas have had taxonomic studies over the past two decades.Fifty-four of the protected sites have had single taxa studies (33 birds-only, 11 insects-only, six small mammalsonly and four plants-only).Atewa Range, Tano-Nimiri, Krokosua Hills and Draw River Forest Reserves, Bui National Park and Kakum-Assin Attandanso Conservation Area have had studies (multiple for except for herpetofauna) in all taxonomic groups and are thus considered the best known sites.

Knowledge gaps
Unlike moths which, despite the availability of large collections of incidence data, has received no systematic study in the country, butterflies in the country have been well-studied (examples are Larsen, 2005;Bossart et al., 2007;Merek and Doku-Marfo, 2009;Larsen et al., 2009;Bossart and Opuni-Frimpong, 2009;Nganso et al., 2012;Aduse-Poku et al., 2012).Butterfly studies have concentrated on only 42 protected areas and seven sacred groves (Table 1).Apart from the rough estimates of butterfly richness for different vegetation types (Table 3), the effects of many anthropogenic land-use systems on the diversity of butterflies still remain unknown.
Despite the new findings available, wide knowledge gaps still exist in all taxonomic groups as previously highlighted in the literature (Ministry of Environment and Science, 2002;Ghana's Report, 2009).In particular, nonlepidopteran insects need to be prioritized in biodiversity studies.These insects, apart from being good indicators of environmental change (Ansah, 2005;Larsen, 2005;Naskrecki, 2007;Kolo et al., 2011), play immense roles in nutrient recycling through wood and leaf litter degradation, soil turnover, dung and carrion disposal, as well as serving as primary food for many animals (Ansah, 2005).However, although a large collection of occurrence data is available in different museum collections outside the country, only a few studies have been conducted on these insects over the last two decades because of taxonomic difficulties (Ansah, 2005;Naskrecki, 2007;Oteng-Yeboah et al., 2009).The fact that approximately 84% of the occurrence records were made more than three decades ago indicates that these arthropods have generally become less popular in recent biodiversity studies.The Coleoptera (largest insect order), for example, has been studied only once over the last decade, and only the Ankasa Conservation Area was covered (that is, Davis and Philips, 2005).Similarly, for Orthoptera, the only recent studies are that of Naskrecki (2007Naskrecki ( , 2009) )  The order Hymenoptera has also had only two recent studies.Belshaw and Bolton (1994) recorded 197 species from 20 different sites with varying vegetation types throughout the forest and transition zones of the country, while Kolo and Hormenyo (2009) recorded 125 species comprising of 98 species from Ajenjua Bepo and 101 species from Mamang River forest reserves.In addition, Deikumah and Kudom (2010) sampled over 15000 individuals from forest patches in Cape Coast and classified them into 52 families, while Ansah (2005) recorded 60, 54 and 49 species from Boin-Tano, Krokosua Hills and Draw River forest reserves, respectively.The other taxonomic orders have not been studied in recent years.
Reptiles and amphibians have also recorded mostly single studies in very few areas of the country and thus need to be given more attention in future studies.Plant diversity, though considered well-known on the basis on extensive work done several decades ago, needs to be studied with particular attention to the savanna zone which is poorly known (Ayensu et al., 1996).With the exception of Asase and Oteng-Yeboah (2007) and Tom-Dery et al. (2012;2013), no other recent, relevant studies on plant diversity in the savanna zone are available.Already, some studies have looked at the plant conservation roles of land-use systems such as mixed crop and cocoa agroforestry by comparing species richness of plants in these systems with species richness of plants in adjacent protected areas (examples are Asase and Tetteh, 2010;Anglaaere et al., 2011;Boakye et al., 2012).However, despite being limited to only few land-use systems, the proximity of these agroforestry systems to the protected areas enhances easy colonization of native species, and hence their outcomes may have been biased towards agroforestry systems since species richness of most widespread species increases significantly in disturbed land-use systems (Waltert et al., 2011).
Birds are also well-known, but unlike plants, knowledge regarding their diversities and distribution over humandominated land-use systems is almost non-existent.
Having lost virtually all forests outside the protected areas which, for centuries past, supported the traditional shifting cultivation system of farming, efforts towards documenting and managing biodiversity in off-reserve areas for continued provision of goods and services for human well-being has become necessary.This knowledge gap is also stated in Ghana Report (2009) as follows: "It is hoped that the other areas, such as in offreserves where no management regimes or plans are in place, will receive adequate attention to become good sources for national indication of successful implementtation of the convention.This achievement will clearly show how biodiversity has been mainstreamed into the society".At present, biodiversity knowledge in off-reserve  areas is too poor and needs attention.

Drivers of biodiversity loss
Ghana is no exception to the present global crisis of biodiversity loss (Myers et al., 2000;Brook et al., 2006).First of all, the population of the country has been increasing (Figure 6) and this has negative effects on biodiversity (Sarkar, 1999;Luck, 2007;Cincotta et al., 2000;McKee et al., 2003;Laurance et al., 2012;Cai and Pettenella, 2013;Bamford et al., 2014).Between 1960 and 2010, for example, the population of the country more than tripled with an average annual population growth between 1921 and 2010 of 3.3% (Ghana Statistical Service, 2013).Presently, the country's populations stands at 25.9 million (CountryStat Ghana, 2014) and is fed mainly from food production on ~65% of terrestrial land (Table 8).
Agriculture is the largest and the most important sector of the country (Benhin and Barbier, 2001) and has been the main agent of deforestation and land-use intensefication since the beginning of the 19th Century (Thompson, 1910;Dickson, 1969;Curry-Lindahl, 1969;Benhin and Barbier, 2001).Food production was low and declining between 1960 and 1983 (Figure 7), and domestic food production was supplemented by food imports.Overall increase in the production of the seven major crops over this period was very small, a factor of 1.1.However, following efforts through the Economic Recovery Program to attain self-sufficiency in food production after the 1983 drought (Ofori-Sarpong, 1986;Attuquayefio and Fobil, 2005), the country has seen an increasing annual trend in food production (Figure 7).In contrast to the period prior to 1983, food production over the same number of years increased substantially by a factor 4.1.This increase in food production corresponddingly resulted in the expansion of the agricultural land area which accelerated the rate of forest loss (Attuquayfio and Fobil, 2005).Twenty-eight years ago, land under cultivation of 30,000 km 2 (Ofori-Sarpong, 1986) which represented only 12.5% of the country's terrestrial land is today 5.2 times more.From FAO's 52-year time-series for the period 1960 -2012, the country's annual crop yield and harvested area which indicate increasing trends are shown in Table 9, Figures 7 and 8.
Of the present land under cultivation, cocoa (24%),   maize (18%), cassava (13%) and yam (9%) alone occupy 63% (CountryStat Ghana, 2014).Despite the forest loss (Benhin and Barbier, 2001;Laurance et al., 2012), landuse intensification (Benton et al. 2003;Hansen and DeFries 2007;Cai and Pettenella 2013), bush burning (Birnin-Yauri and Aliero, 2008;Thompson, 1910), etc. associated with annual food crop cultivation, cocoa cultivation, the dominant agricultural activity in terms of land coverage, is problematic to biodiversity conservation because of its associated farming practices such as insecticide spraying (Padi and Owusu, 2003;Afrane and Ntiamoah, 2011;Tscharntke et al., 2012;Schiesari et al., 2013) and the elimination of other water-competing or pest-hosting plants (N'goran, 1998).Crop production has been restricted to the forest and the forest-savanna transition regions of the country due to land suitability.However, comparison between land under crop cultivation and suitable land indicates that in the future, production increases in crops cannot depend on area expansion (Breisinger et al., 2008).With no hope of expansion in cropland, further land-use intensification is expected if food sufficiency is to be attained.Further land-use intensification could potentially have ecological (taxonomic and functional) decay consequences on both off-reserve biodiversity and on biodiversity inside protected reserves (Baillie et al., 2000;Hansen and DeFries, 2007;Laurance et al., 2012;Cai and Pettenella, 2013;Hamilton et al., 2013).Land-use effects on protected areas include reduction in effective size and alteration of ecological flows (Curran et al., 2004;Hansen and DeFries, 2007), and disruption of sourcesink dynamics of ecosystems though the elimination of unique source habitats (Hansen and Rotella, 2002;Hansen and DeFries, 2007), edge effects (Hansen and DeFries, 2007;Bossart and Opuni-Frimpong, 2009;Laurance et al., 2012), increasing reserve isolation (Laurance et al., 2012) and reduction in habitat amount (Fahrig, 2013).In human-dominated land-use systems, ecological processes such as dispersal which naturally promote biodiversity could lead to population reduction and subsequently range contraction (Baillie et al., 2000;Benton et al., 2003) as well as landscape homogeneity.This is because dispersal could transport range-restricted species to poor-quality, unfavorable habitats (Benton et al., 2003) and widespread, invasive species to new, favorable habitats where they can spread rapidly.Thus, prioritizing studies that properly map land-use effects on biodiversity is necessary to ensure systematic conservation planning inside and outside protected reserves.

Restoration of degraded forest reserve through natural regeneration
It has been reported that biological recovery and regeneration is high not only for plants in highly degraded areas of the country (Lugo et al., 1993;Decher, 1997;Anyomi et al., 2011;Appiah, 2011;Boakye et al., 2012) including areas that have consistently experienced annual bushfires (Tom-Dery et al., 2013), but also animals (Curry-Lindahl, 1969) in both the savanna and forest zones (Decher and Bahian, 1999).Within a period of 30 to 40 years, forests area which have completely degraded into savanna can be re-established provided those areas are protected from wildfires (Lugo et al., 1993;Decher, 1997).There is sufficient evidence that without further human interferences, degraded areas of the country's forest reserves can potentially undergo natural restoration into forest habitats.This notwithstanding, reforestation of degraded forest reserves is important to speed up biodiversity recovery.However, when exotic species are highly represented, it defeats the purpose of the reserves and violates some of the guidelines contained in the Forestry and Wildlife Policy (Ministry of Lands and Forestry, 1994) of the country.McCullough et al. (2005) has already described as inappropriate, an attempt to replant degraded parts of the Krokosua Hills Globally Significant Biodiversity Area with Cedrela odorata.Larsen (2005) has also described this practice as a means of creating vegetative areas which are effectively biodiversity deserts, for which reason it should not be tolerated.While acknowledging that this practice has some historical support, it should not be considered at this time because there are several studies available on cheaper methods for restoring degraded tropical forests (Lamb et al., 2005;Shono et al., 2007;Holl, 2013).

Conservation campaigns should lead to voluntary participation
For over a century, the desire to preserve wilderness (Sarkar, 1999) and knowledge that loss of natural forest cover causes biodiversity loss, have driven conservation activities worldwide.Protected area systems of conser-vation are examples but their benefits are hardly noticed due to insufficient public knowledge, lack of alternative livelihood support for nearby communities, and the fact that there is almost zero interaction between a majority of the people and these reserves.Often, attempts to involve fringe communities in conservation efforts fail due to biased selection of co-management members, corruption in management and exclusion of locals from promised benefits (Songorwa, 1999;Sarker and Røskaft, 2011).Thus, residents of these communities usually engage in farming activities of varying intensities which gradually extend the agricultural frontier uncontrollably into the buffer zones (Bamford et al., 2014), leaving the protected areas as isolated islands (Sarkar, 1999).
Already, since the year 2000, The Rufford Foundation, a charitable organization based in the UK, has funded over 40, one-year duration biodiversity conservation projects costing over £260000 in the country (http://www.rufford.org/projects/byCountry/GH)(Table 10).These projects, together with several other short and

Target Audience
Conservation Target Community conservation (24) Habitat conservation/restoration (12) General public ( 14) Amphibians ( 11) Students ( 6 (Songorwa, 1999;Sarker and Røskaft, 2011).In local communities, most people (perhaps greater than 90%) depend fully on farming for food, and resource extraction for other needs related to fuel, shelter and health.Therefore, running educational campaigns of "no-entry" into reserves contribute very little, if not nothing, to conversation because no one without the basic survival needs will truly show interest in such conservation messages (Sarker and Røskaft, 2011).There is the need to build a better conservation strategy which attracts the voluntary participation of the least-income earners (Kumaraswamy and Kunte, 2013).
Given the present low protection of protected areas, alternative solutions which allow quota-based hunting (Songorwa, 1999;Kangalawe and Noe, 2012), firewood and other resource extraction in legally-designated areas (Sarker and Røskaft, 2011), as well as financial incentives for reserve protection (Sarker and Røskaft 2011) should be considered.The need to monitor and rid such systems of improper management and corruption (Songorwa, 1999;Sarker and Røskaft, 2011) is also essential.Moreover, there is the need to support studies which seek to identify threatened species and their distribution ranges so that location-based educational campaigns could be launched.Such campaigns should educate the target groups to properly understand the consequences of their continued dependence on such species using relevant research findings as well as similar cases from other locations.As a long-term project, primary, secondary and tertiary educational institutions should be considered effective vehicles for promoting the spirit of biodiversity conservation (Anyomi et al., 2008).Without these measures, it would be difficult to attract peoples' voluntary participation in conservation projects and all efforts will break down at some point as population increases.

Insects need to be prioritized in biodiversity studies
As discussed above and also in previous publications (Anyomi et al., 2008;Boshier et al., 2011), the situation of T. gentii and S. fimbrisepala brings into focus the thought that the country, like other tropical countries, could be experiencing several unknown losses, and perhaps mass extinctions (Sodhi et al., 2009), of several important species because of the present gaps in relevant information.Already, Larsen (2006) has reported that one out of 10 insect species found in Ghana could be new to science, and thus significant effort need to be put into finding out the ecological status of the insect groups whose ecology and distribution across different land-use systems in the country is largely unknown.
The lack of insect taxonomists as already reported (Ansah, 2005;Naskrecki, 2007;Oteng-Yeboah, et al. 2009) deserves urgent consideration but should not be a setback to ecological knowledge acquisition.As Hobson (2014) points out "the first step to solving any problem is to not hide from it…" and besides, insects have a myriad of characteristics which make them strong candidates as species surrogates in studies that quantify the effects of environmental changes on biological systems.Insects are globally ubiquitous (Bossart and Opuni-Frimpong, 2009), are highly sensitive to anthropogenic and climatic disturbances (Kremen et al., 1993;Oliver and Beattie, 1996;Ward and Lariviere, 2004;Natural Resources Canada, 2010;Koch et al., 2013) and have large species assemblages (Beccaloni and Gaston, 1995;Natural Resources Canada, 2010) which allows them to broaden the scope of ecosystem factors that can be perceived (Kremen et al., 1993).They also contribute more than 90% of genetic variability (Duelli, 1997), they are tractable study species (Morris, 2010), they provide early warning of ecological changes (Kremen et al., 1993), they have high rate of endemism and speciation (Bossart and Opuni-Frimpong, 2009), and their diversity is highly correlated with that of vertebrates (Caro, 2010).
Besides the many desirable characteristics of insects, the taxonomic impediment could be overcome by identifying individuals to genus level (Caro, 2010).For rapid assessments (and in cases of financial constraints), careful identification to morphospecies by non-experts with basic training has been tested and proved to be sufficient (Oliver and Beattie, 1993, 1996, 1997;Ward and Lariviere, 2004;Obrist and Duelli, 2010;Derraik et al., 2002Derraik et al., , 2010)), even though this method has been criticized (Goldstein, 1997;Krell, 2004).Fortunately, countries such as Switzerland, Australia, New Zealand, Canada, etc., have already made great advances in using insects for biodiversity monitoring and their experience is an asset.

The need for data-driven conservation plans
The need to seek knowledge on the state of biodiversity in human-dominated land-use systems cannot be overem-phasized (Kumaraswamy and Kunte, 2013), even though diversity is generally known to be low in these systems (Larsen, 2005;Davis and Philips, 2005;Bossart and Opuni-Frimpong, 2009).Landscape-scale studies which describe changes across different biodiversity groups in relation to land-use have become necessary in order to fill in knowledge gaps (Norris et al., 2010;Kumaraswamy and Kunte, 2013).Because it takes years of observation to record a significant amount of species, focus should be on the effects of the interaction between these systems and biodiversity (Ntiamoa-Baidu et al., 2000;Larsen, 2005).The outcome of such studies is the identification of a set of land-use activities for different areas which conserve different sets of ecologicallyimportant species (Kumaraswamy and Kunte, 2013).This knowledge is necessary for off-reserve biodiversity conservation.Essentially, as areas get degraded some species adapt to the changes while others do not, and enrichment of these areas is possible under better land-use management (Tscharntke et al., 2012).
It is increasingly becoming clear that the protected area system of biodiversity conservation needs to be complemented by off-reserve conservation in order to make it more effective (Hansen and DeFries, 2007;Anand et al., 2010;Brussaard et al., 2010;Plieninger and Gaertner, 2011;Cai and Pettenella, 2013;Fahrig, 2013;Kumaraswamy and Kunte, 2013).Innovative land-use programmes for both crop yield improvement and farmland biodiversity conservation based on well-formulated policies should therefore be pursued (Benton et al., 2003;Anand et al., 2010;Kumaraswamy and Kunte, 2013;Baral et al., 2014).This naturally leads to a system in which food security for all people and biodiversity conservation are jointly achieved (Brussaard et al., 2010;Tscharntke et al., 2012).Thus, the problem of biodiversity conservation is a constrained optimization problem which cannot be solved in a vacuum, but must be linked with the food security of the lowest income earners (Tscharntke et al., 2012).
Adequate quality agro-ecological data is needed (Kumaraswamy and Kunte, 2013).Fortunately, the freely available high-resolution global land-use/cover products (for example, Gong et al., 2013; (http://data.ess.tsinghua.edu.cn/);Wang et al. 2014, etc) can be utilized in landscape-scale ecological assessments (for example, Fuller et al., 1998;Reidsma et al., 2006;Baral et al., 2014) to obtain the necessary ecological data, despite the belief that variability in farmland size make this pursuit difficult (Kumaraswamy and Kunte, 2013).Given data on agricultural variables, a locally-suitable, optimized land-use management solution can be developed.Already, the traditional systems of farming practiced predominantly in the northern regions of the country and Burkina Faso, in which native woody plants are interspersed with crops, and cocoa farming systems in the forest zone have ideal features that could facilitate easy integration into optimized land-use plans (also known as offset mechanisms; Kumaraswamy and Kunte, 2013).As Tscharntke et al. (2012) have indicated, biodiversity conservation and environmental cost minimization are achievable in the tropics amidst agroecological intensification.

Figure 1 .
Figure 1.The map of Ghana.

Figure 2 .
Figure 2. Richness of birds, butterflies, small and large mammals.

Figure 5 .
Figure 5. Spatial distribution of sites studied and the taxa of interest.

Figure 7 .
Figure 7. Trends in annual production of major crops in Ghana (Source of data: FAO 2014).

Figure 8 .
Figure 8. Trends in harvested area of major crops in Ghana (Source of data: FAO 2014).

Table 1
Summary of dataset distribution from literature for different taxa groups and habitat types in Ghana.

Table 2 .
Summary of bird species per region.

Table 3 .
Larsen (2006)cies richness and distribution according to rainfall and vegetation cover, produced based on estimated proportions inLarsen (2006).The proportions were calculated using the total butterfly richness (983) of the country.

Table 5 .
Summary of mammal species in Ghana.The terms near threatened, vulnerable and endangered are as defined by the IUCN.

Table 7 .
Summary of reptile families in Ghana.
which recorded 61, 50 and 33 species of

Table 8 .
Land-use share of Ghana's land area.

Table 10 .
Summary of conservation projects sponsored by The Rufford Foundation.The number of studies under each item is in brackets.