Amphibian community along elevational and habitat disturbance gradients in the Taita Hills, Kenya/Comunidad de anfibios a lo largo de gradientes altitudinales y de perturbacion de habitat en Taita Hills, Kenia.
Spatial patterns in species richness have fascinated biologists for decades and the search for their causes has been a centre of focus in the field of community ecology and/or conservation biogeography for decades (Heaney 2001). What is clear is that the distribution of organisms is not random (Rahbek 1997). The need to document and understand species patterns especially for the lower taxa are increasingly becoming important as threats to biodiversity escalates.
Modern interest has focused on distributions along latitudinal and elevational gradients and the processes that control these patterns (Colwell et al. 2004, Watkins et al. 2006). In both patterns there is an inverse relationship between species richness and elevation and latitude (Rahbek 1997, Willig et al. 2003, Carpenter 2005, Watkin et al. 2006). Studies on elevational gradients have observed two main patterns of species richness: first a monotonical decrease in richness with increasing elevation and second, a "humped" distribution, with species richness highest near the middle of the gradient (Watkins et al. 2006).
Irrespective of elevation, human disturbance of habitats continue to change species composition and distribution world-wide. Habitat loss and fragmentation is one of the major threats to biodiversity (Fahrig 2003, Ross et al. 2002, Kupfer et al. 2005, Taberelli and Gascon 2005, Ewers and Didham 2006, Cayuela et al. 2006, Bell and Donnelly 2006). Consequently, throughout the world, previously extensive tracts of natural habitat now exist as isolated fragments scattered across inhospitable landscapes (Benedick et al. 2006). This is evident in tropical regions, where remnants of forests exist within agricultural or urban landscapes, resulting in the remaining forest patches supporting increasingly isolated populations of forest dependent species (Raman 2006, Benedick et al. 2006). In tropical areas, amphibian studies have mainly focussed on species diversity and richness, with some conducted in anthropogenically fragmented environments (e.g. Marsh and Pearman 1997, Wind 2000, Vallan 2000, Pineda and Halffter 2004, Ernst and Rodel 2005, Neckel-Oliveira and Gascon 2006, Bell and Donnelly 2006, Cushman 2006, Hillers et al. 2008). For example, many forest-dependent species have been shown to be detrimentally affected by habitat loss and degradation, and there are cases of species going locally extinct when forest fragments are too small to support viable populations (Watson et al. 2004). Rare species, species with low dispersal abilities, large area requirements, low fecundity, low population densities, abundance or high population variability, habitat and food specialists are most affected by habitat loss and fragmentation (Bell and Donnelly, 2006).
Understanding species richness patterns in montane regions is important as most of them are centres of species diversity and endemism in the tropical regions (Smith et al. 2007). Currently little is known about the underlying factors that govern species distribution patterns. However, extensive literature suggests that contemporary climate with its control on energy dynamics constrains terrestrial taxonomic richness over broad geographic extents (Hawkins et al. 2003a). Climatic, biological, and historical factors have been suggested as causes of variation in species richness along elevational gradients (Rahbek 1997, Sanders et al. 2003). Climate through water-energy dynamics hypothesis has influence on primary productivity (Hawkins et al. 2003b) which in turn is positively correlated with species richness (Sanders 2002, Hawkins et al. 2003a).
No study has examined patterns of amphibian species richness and composition at different disturbance and elevation levels in the in the Eastern Arc Mountains (EAM) of Eastern Africa. The Taita Hills is one of the EAM Mountain blocks suitable for understanding the response of amphibian to elevation and anthropogenic habitat disturbance. Otherwise it is imperative to understand how amphibian communities and individual species are distributed in order to formulate viable conservation and management options. The Taita Hills has the least amount of remaining forest (about 2% of the original forest) making it the most fragmented and endangered block in the EAM (Newmark 1998). Despite having the smallest remaining forest area, it has three endemic amphibians; namely, Boulengerula taitana Loveridge, 1935, Boulengerula niedeni Muller, Measey, Loader et Malonza, 2005 and Callulina dawida Loader, Measey, de Sa et Malonza, 2009.
It is therefore essential to ascertain how amphibian communities and individual species are affected by deforestation, habitat fragmentation and modification to derive appropriate ecosystem management options.
In this paper we aim to asses how anthropogenic habitat disturbance along the Taita Hills elevational gradient affect amphibian community. We test the hypotheses that (1) there is a clear amphibian species turnover with elevation, and (2) human habitat disturbance and elevation influence abundance of amphibian reproductive strategies. Predictably sites within similar disturbance regime and/ or elevations should group together. Amphibians have been used as bio-indicators because they are easy to quantify and have relatively narrow moisture and temperature tolerances (Duellman and Trueb 1994). Forest loss has been found to cause micro-climate alteration such as higher temperatures, lower soil and atmospheric humidity as well as increasing wind velocity in the tropics (Pineda and Halffter 2004, Ernst et al. 2006). Previous studies have shown that deforestation and habitat modification affect amphibian communities in tropical forests (e.g. Pearman 1997, Vallan 2000, 2002, Vallan et al. 2004, Pineda and Halffter 2004, Bell and Donnelly 2006). In particular, species with direct development reproductive mode (e.g. deposit eggs on leaf) are very sensitive to changes in moisture regime and leaf litter depth (Marsh and Pearman 1997).
MATERIALS AND METHODS
The Taita Hills is the northern outlier of the EAM, a well known biodiversity hotspot (Myers et al. 2000). The EAM is a chain of 13 ancient, crystalline blocks, arranged as an arc, and located in Eastern Africa (Tanzania and Kenya) overlooking the Indian Ocean (Lovett 1990). The Taita Hills complex consists of the main block (Dawida, 2228 m) c. 25km north-west of Voi and three other blocks: Mt. Mbololo (2149 m), Sagalla Hill (1520 m), and Mt. Kasigau (1645 m), approximately 5, 25 and 50 km respectively from Dawida. Sagalla Hill, directly south of Voi, is separated from Dawida and Mbololo by the Voi River on the Tsavo plains, while Mt. Mbololo is separated from Dawida by the Paranga valley at c. 900 m. Dawida has its highest peak at Vuria (2228 m); other high peaks are Ngangao (2109 m) and Iyale (2149 m) (Fig. 1). The three blocks rise from different altitudes depending on their location. Dawida and Mbololo rise from an altitude of about 800 m, while Sagalla and Kasigau are from altitudes of about 700 m and 600 m, respectively. The lower slopes of the hills are covered by dry bush land that change abruptly after c. 1000 m to small-holder cultivation and remnant patches of moist forest. As a result of the high human pressure on land, forest remains only as scattered fragments on hilltops and ridges totalling 400 ha. Mt. Kasigau hilltop moist forest is c. 20 ha, Sagalla retains only c. 3 ha of moist forest and Mbololo c. 220 ha along the hill crest, while the main block (Dawida) has a number of tiny remnants that range in size from 1 to 92 ha, including Fururu (12 ha), Mwachora (4 ha), Macha (3 ha), Ndiwenyi (3 ha), Ngerenyi (3 ha), Kichuchenyi (2 ha), Iyale (2 ha) and Vuria (1 ha), and two larger patches: Chawia (c. 50 ha) and Ngangao (c. 92 ha) see Brooks et al. (1998). Beentje (1987) estimate the indigenous forest loss since 1960s in the major fragments as 99%, 95%, 85%, 50% and under 50% for Vuria, Sagalla, Chawia, Ngangao and Mbololo, respectively, but recognized Kasigau as relatively undisturbed.
The patterns of human settlements on the Taita Hills are dependent on water availability with the main land use type in the Taita Hills being small scale intensive agriculture and forestry. It has one of the highest and ever increasing rural human population densities in Kenya (Mwagore 2005). The majority of farming activities are either on the valleys and slopes, hill tops or in the foothills of each block. It is also in these areas where there are wetlands that are the preferred habitats for many amphibians. While the people on the hilltops depend on high rainfall, those at the base depend mainly on flooding from the highlands. Mean annual temperatures decrease (22 to 16[degrees]C) while rainfall increases (600 to 1400 mm) with elevation DD(Jatzold and Schmidt 1983). The remnant moist natural forests are confined to the hilltops mainly from 1300-2200 m. The majority of the hilltops and slopes in the highland areas are now covered by pine and eucalyptus plantations.
[FIGURE 1 OMITTED]
Definition of habitats
The habitats investigated include:
1) Terrestrial: a) Forests: In this study, this refers to indigenous montane cloud forest and, b) plantations comprising a mixture and/ or pure stands of eucalyptus (Eucalyptus spp.) and pine (Pinus spp.) most of which were re-planted in areas that used to be covered by indigenous forests. Both forests and plantations are located at high elevations (> 1000 m).
2) Aquatic habitats: These were mainly streams and man-made dams. All were within agricultural lands on the foothills and/or highland valleys.
1a) Forests (n = 8): Ngangao (1854 m), Chawia (1610 m), Mwachora (1644 m), Macha (1650 m), Boma-Wundanyi (1439 m), Mbololo (1770 m), Sagalla (1504 m), Mount Kasigau (1600 m).
1b) Plantations (n = 4): Kinyesha-mvua (1612 m), Sungululu (1483 m), Mwambirwa (1300 m), Sagalla (1384).
2a) Aquatic--streams (n = 11): Chale (1236 m), Mwalenjo (1292 m), Mwasange (1309 m), Marapu (651 m), Mghange (1273 m), Kauze (1081 m), Piringa (1187 m), Mndangenyi (1397 m), Mbirwa (1430 m), Mghambonyi (1546 m) Madungunyi (846 m).
2b) Aquatic--dams (n = 6) Bafwe (577 m), Hezron (563 m), Lata (1064m), Makandenyi (1647 m), Ngulu (1600 m), Mwatate (839 m). Sites below 1000 m were designated as lowland and those above 1000 m as highland.
We sampled amphibians using 600 x 1 m transects (Rodel and Ernst 2004, Veith et al. 2004) continuously from April 2006 to January 2007. In total we had 29 transect sites within the two broad habitats (terrestrial and aquatic). There were six observers assignable to six clusters of transects, meaning that each observer had a maximum of five transects to sample. Each transect was sampled at least once every week covering both dry and wet seasons. A standard time of 1 hour sampling was spent in each transect and interrupted only when recording data. The number of samples for each transect are given in Table 1.
Identification of the specimens was made using published taxonomic keys and followed taxonomy by Frost et al. (2006) and Frost (2007). Selected individuals of underrepresented species were kept as voucher specimens and deposited in National Museums of Kenya (NMK). Tissue samples for future DNA analysis were taken for majority of the specimens and stored in absolute ethanol.
The explanatory power of climatic factors on amphibian species richness patterns was assessed. Average minimum and maximum daily rainfall and temperature were estimated from data gathered from daily records for most sites. Geographic location was based on GPS data, Garmin[R] 12XL (Garmin International, Olathe, Kansas, USA).
Species richness and diversity for each transect was estimated using EstimateS 7.5.1 program (Colwell 2006). Amphibian species diversity among transect sites was measured with Shannon Index (H'). Non-parametric Kruskal-Wallis H test was used to compare amphibian species abundance and species richness among transects within the same elevation cluster and habitat type.
Amphibian similarity between sampling sites was calculated using Sorensen similarity index. This index is based on the probability that two randomly chosen individuals, one from each site, belong to a species shared by both sites (but not necessarily to the same species (Watkins et al. 2006). It was calculated as: [C.sub.s] = 2j/ (a+b), where j equals the number of species shared between two sites, and a and b are the number of species in each site. The index ranges from 0, when adjacent communities share no species in common, to 1, when adjacent communities are identical. To investigate the influence of habitat type on amphibian species composition, a distance matrix based on Sorensen qualitative similarity index was generated. Using STATISTICA 6.0 (StatSoft 2001) the resultant matrix was converted into a dendrogram using complete linkage cluster analysis.
Mt. Kasigau was omitted in the diversity analyses because no species was recorded during all the transect surveys. For uniform comparability we compared data from only the streams and dams in high altitude areas, excluding the lowland sites. Data was analyzed with STATISTICA 6.0 software (StatSoft 2001), with significance levels set at [alpha] = 0.05.
Species richness and diversity
We recorded 5577 amphibian individuals of 23 species from all the 29 transect sites (Table 2). In terrestrial habitats we recorded five and three species in forests and plantations respectively. However, there was no significant difference in richness and the Shannon diversity index (H) (Kruskal-Wallis: richness, H = 1.96, df = 1, N = 177, P = 0.16; diversity, H = 2.91, df = 1, N = 11, P = 0.08). Again, comparing every survey (sample), the number species observed was also not significant (H = 1.96, df = 1, N = 177, P = 0.16).
Eleven and twelve species were observed in highland streams and dams respectively. Species diversity among streams and dams was not significantly different (H = 1.93, df = 1, N = 12, P = 0.16). However, comparing the number of species observed per sample (survey) they were significantly higher in dams than streams (Kruskal-Wallis: richness, H = 19.059, df = 1, N = 196, P < 0.001).
Patterns of species richness along elevation and disturbance gradient
There was clear altitudinal species turnover from lowland to highland. While there were some widespread species there were notable lowland species such as Hyperolius tuberlinguis (Smith, 1849), Hildebrandtia macrotympanum (Boulenger, 1912), Chiromantis kelleri Boettger, 1893 and Ptychadena mossambica (Peters, 1854). Boulengerula taitana, Callulina dawida, Arthroleptis xenodactyloides Hewitt, 1933 and Amietia angolensis (Bocage, 1866) were restricted to the highlands. The results of cluster analysis of all transects produced two major clusters of species assemblages according to their responses to the habitat type and elevation band (highland streams/dams and forests/plantations) plus a sub-cluster of typical lowland streams and dams (Fig. 2). Generally, there were more amphibian species at low to mid-elevation streams and dams and less in forests and plantations at high altitudes.
Species response to habitat disturbance level
The results on patterns of species distribution clearly show absence of certain species in some habitats. The frog Callulina dawida was only found in indigenous forests. The leaf litter frog Arthroleptis xenodactyloides was confined mainly to forests and plantations, while Amietia angolensis occurred in highland streams. Dams were mainly dominated by open water breeders.
Response of species to habitat disturbance and elevation gradient The results on local amphibian species richness in the Taita Hills show that species abundance and richness differs significantly among the two broad habitat types (terrestrial and aquatic). Aquatic streams and dams in the highlands contained significantly more species than terrestrial forests and plantations. The results show that plantations were very depauperate in both species richness and number of individuals. Overall species richness and abundance positively increased with disturbance level from forests through streams to dams. However, considering species reproductive phylogeny (strategy) forest associated direct developing species (Arthroleptis xenodactyloides, Callulina dawida and Boulengerula taitana) decreased with increased disturbance from forests to aquatic habitats. These results concur with those of Lea et al. (2005) in Nigerian rainforests who observed that, following degradation of rainforests to other human modified habitats, species richness may remain constant or locally increase. However, these results contrast with several similar studies which have shown that species richness decreases from indigenous forests, through plantations to farms (Pineda and Halffter 2004).
Species richness was high at low to mid elevations and few at high elevations. In Taita Hills, rainfall increases with elevation while temperature decreases (Jatzold and Schmidt 1983). This pattern agrees with that reported by many previous studies on a wide range of taxonomic groups (Heaney 2001, Smith et al. 2007). Despite the high rainfall at high elevations in the Taita Hills, much of the water as observed elsewhere settles on mid-elevations and the rest on the foot hills therein creating breeding sites for open water breeders (Hofer et al. 2000). This observation is in agreement with past studies that have demonstrated high species richness as a product of high energy (temperature) and primary productivity (Hawkins et al. 2003b, Willig et al. 2003). Energy in form of temperature and rainfall (water) are known indirect measures of net primary productivity and hence increased species richness (Sanders et al. 2003).
[FIGURE 2 OMITTED]
In Taita Hills, certain species (with direct developing reproductive mode) are restricted to high elevation forests (e.g. Callulina dawida). Similarly, on Mount Kupe, Cameroon, Hofer et al. (2000) suggested that the dependence of most amphibians on aquatic breeding sites that were not available at all elevations reduced the relative importance of elevational gradient on amphibian species distributions. However, on a finer scale as evident in Taita Hills, they observed a significant response to amphibian species that do not depend on streams for development (i.e. direct developers) to elevational gradient variables. In cluster analysis, sites similar in disturbance and elevation clustered together reflecting their similarity in amphibian community.
Implications for conservation management
In Taita Hills direct developing amphibian species in forests (Callulina dawida, Arthroleptis xenodactyloides, Boulengerula niedeni, Boulengerula taitana) occur only in terrestrial forests and are absent in aquatic habitats. This suggests that the loss of forest cover result in the loss of the conditions (microclimate) required for supporting these species by altering the functional diversity (e.g. forest associated species). Elsewhere, microclimate change has been found to negatively impact leaf litter frogs (e.g. Ernst and Rodel 2005, Ernst et al. 2006, Hillers et al. 2008). This may be due to physiological or ecological factors. Higher temperatures, lower soil and atmospheric humidity, leaf litter loss, as well as increasing wind velocity are some of the consequences of forest removal (Marsh and Pearman 1997, Pineda and Halffter 2004). In general, amphibians need to keep their skin moist to allow gaseous exchange and depend on external heat to regulate their internal temperature (Duellman and Trueb 1994). The eggs of such species (direct developers) are exposed to the atmosphere and with reduced humidity would be vulnerable to desiccation. Therefore, simplification of the vegetation structure could reduce the availability of oviposition sites mainly for species that deposit their eggs on leaf litter (Vallan 2000, 2002). Consequently, in Taita Hills certain species like Callulina dawida and Arthroleptis xenodactyloides can serve as potential bio-indicators of forest quality. Other studies in the tropics have also identified certain herpetofauna as good indicators of forest quality and fragmentation (e.g. Urbina-Cardona et al. 2006, Bell and Donnelly 2006).
On the other hand, the proportions of arboreal and/or open water breeding species in Taita Hills increased from terrestrial forests to aquatic dams. Basically, the reduction in forest patch size or area is related to decreasing environmental heterogeneity at ground level, resulting in the loss of microhabitats, breeding sites and territory for several species. Hence, terrestrial or ground living species would be most affected. However, it appears that this group of species is insensitive to reduction or change in forest cover. For arboreal species, one reason is that in spite of dwindling forest cover, their microhabitats' patchiness may not be affected or may even increase since high canopy may not be crucial. For open water breeders small loss of forest cover should be related to a decrease in availability of the microhabitats (ponds and streams) required for oviposition (Pineda and Halffter 2004), for these species the presence of a body of water (breeding sites) has stronger positive effect than that of the forest loss. This concurs with findings by Vallan (2002) in rainforests of Madagascar, Pineda and Halffter (2004) in a montane forest in Mexico, and Hillers et al. (2008) in Tai National Park and selected forest fragments in Ivory Coast.
Plantations generally had few numbers of species and guilds attributable solely to their habitat structural simplicity such as lack of wetlands and leaf litter. Plantation stands may have such a dense canopy or produce chemicals virtually excluding other plant taxa (Evans 1982).
In Taita Hills, conservation investments should be directed towards the terrestrial indigenous forests. Although forests were generally poor in species richness than aquatic streams and dams, it is only here where you have direct developing amphibians. Among these are the three Taita Hills endangered endemics (Malonza 2008). The caecilian Boulengerula niedeni is caterogized by IUCN as Critically Endangered (CR) (www.iucnredlist.org/amphibians) while the Boulengerula taitana and the warty frog Callulina dawida are both proposed to be listed as Vulnerable (VU) and CR, respectively, following IUCN criteria (Malonza 2008). To protect these endemics, we therefore propose a framework for identifying priority areas for amphibian conservation that focus on indigenous forests. Hence, we recommend the continued maintenance of a set of forest fragments together with the human modified habitats extensively distributed (Pineda and Halfter 2004) including some form of habitat connectivity (e.g. corridors) (Cushman 2006, Akcakaya et al. 2007). We also strongly support restoration programmes of gradually replacing exotic plantations with indigenous plants.
This study clearly shows that species response to disturbance and elevation gradient depends on particular species reproductive strategy. Species with direct development mode of breeding are restricted to terrestrial forests in high elevations. These are as well the most affected by human habitat modifications. Most of these disappear with loss of indigenous forests and any conservation efforts should be directed towards their protection for continued survival of the Taita Hills endemics.
We are very grateful to our Taita Hills field assistants, namely Peter Mwasi, Peter Alama, Oliver Mwakio, Bigvai Karingo, Greshon Kisombe and Rensone Dio, who helped in surveys. Thanks go to the local community and Kenya Forest Service personnel in Taita, who allowed sampling within forest reserves and community lands. PKM is very grateful to National Museums of Kenya for granting him a study leave to work in Taita Hills. We also acknowledge the study with a PhD student scholarship funds by the Katholischer Akademischer Auslander-Dienst (KAAD), Bonn, Germany to PKM as well as logistic support from the BIOLOG BIOTA East Africa project (Federal Ministry of Education and research, Germany) and Critical Ecosystem Partnership Fund (CEPF).
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PATRICK K. MALONZA (1,3) and MICHAEL VEITH (2)
(1) Section of Herpetology, National Museums of Kenya, P. O. Box 40658-00100 Nairobi, Kenya.
(2) Department of Biogeography, University of Trier, 54286 Trier, Germany.
(3) Send correspondence to / Enviar correspondencia a: email@example.com
TABLE 1. Number of samples and species observed in different transects in both terrestrial and aquatic habitats. TABLA 1. Numero de muestras y especies observadas en diferentes transectos en ambos habitats terrestre y acuatico. Transect Habitat type Number Number of species of observed samples ([+ or -] SD) Ngangao Forest 17 2 [+ or -] 0.53 Chawia Forest 16 2 [+ or -] 0.49 Mwachora Forest 16 1 [+ or -] 0.40 Macha Forest 15 2 [+ or -] 0.51 Boma Forest 18 2 [+ or -] 0.23 Sungululu Plantation 16 1 [+ or -] 0.48 Kinyesha-mvua Plantation 14 3 [+ or -] 0.36 Mndangenyi Aquatic stream 16 4 [+ or -] 0.70 Mbirwa Aquatic stream 17 5 [+ or -] 0.72 Mghambonyi Aquatic stream 13 5 [+ or -] 0.59 Makandenyi Aquatic dam 12 6 [+ or -] 0.78 Piringa Aquatic stream 18 5 [+ or -] 1.15 Ngulu Aquatic dam 16 7 [+ or -] 1.37 Mwatate Aquatic dam 19 8 [+ or -] 1.99 Madungunyi Aquatic stream 18 7 [+ or -] 1.35 Mbololo Forest 21 2 [+ or -] 0.30 Mwambirwa Plantation 17 2 [+ or -] 0.44 Mwasange Aquatic stream 19 8 [+ or -] 1.24 Mwalenjo Aquatic stream 19 6 [+ or -] 0.85 Chale Aquatic stream 16 5 [+ or -] 1.12 Sagalla Forest 15 2 [+ or -] 0.26 Sagalla Plantation 16 1 [+ or -] 0.34 Mghange Aquatic stream 13 5 [+ or -] 1.28 Kauze Aquatic stream 17 6 [+ or -] 1.34 Lata Aquatic dam 18 9 [+ or -] 1.21 Marapu Aquatic stream 16 4 [+ or -] 0.92 Hezron Aquatic dam 14 9 [+ or -] 1.76 Bafwe Aquatic dam 16 10 [+ or -] 1.80 Kasigau Forest 16 0 [+ or -] 0 TABLE 2. The 23 species and the respective number of individuals recorded in different habitats, plus their reproductive estrategy. TABLA 2. Las 23 especies y su respectivo numero de individuos registrados en diferentes habitats, mas su estrategia reproductiva. Species Terrestrial- Terrestrial- Aquatic- Forest Plantation Stream Boulengerula taitana 2 0 0 Xenopus borealis 0 0 91 Amietophrynus garmani 0 0 5 Amietophrynus gutturalis 2 2 219 Amietophrynus xeros 0 0 4 Mertensophryne taitana 0 0 1 Phrynomantis bifasciatus 0 0 0 Callulina dawida 7 0 0 Hemisus marmoratus 0 0 0 Arthroleptis xenodactyloides 441 159 14 Leptopelis concolor 0 0 84 Hyperolius glandicolor 3 1 808 Hyperolius tuberilinguis 0 0 0 Kassina senegalensis 0 0 0 Hildebrandtia macrotympanum 0 0 0 Ptychadena anchietae 0 0 128 Ptychadena mascareniensis 0 0 137 Ptychadena mossambica 0 0 2 Phrynobatrachus scheffleri 0 0 11 Amietia angolensis 0 0 20 Tomopterna cryptotis 0 0 0 Chiromantis kelleri 0 0 0 Chiromantis petersi 0 0 0 Species Aquatic- Habits Reproductive Dam mode/strategy Boulengerula taitana 0 Fossorial Direct developer Xenopus borealis 99 Aquatic Open water Amietophrynus garmani 23 Terrestrial Open water Amietophrynus gutturalis 116 Terrestrial Open water Amietophrynus xeros 125 Terrestrial Open water Mertensophryne taitana 0 Terrestrial Open water Phrynomantis bifasciatus 146 Terrestrial Open water Callulina dawida 0 Fossorial/ Direct developer Hemisus marmoratus 22 arboreal Open water Arthroleptis xenodactyloides 0 Fossorial Direct developer Leptopelis concolor 201 Terrestrial Open water Hyperolius glandicolor 1581 Arboreal Open water Hyperolius tuberilinguis 86 Arboreal Open water Kassina senegalensis 86 Arboreal Open water Hildebrandtia macrotympanum 15 Terrestrial Open water Ptychadena anchietae 464 Fossorial Open water Ptychadena mascareniensis 229 Terrestrial Open water Ptychadena mossambica 0 Terrestrial Open water Phrynobatrachus scheffleri 12 Terrestrial Open water Amietia angolensis 0 Terrestrial Open water Tomopterna cryptotis 45 Terrestrial Open water Chiromantis kelleri 6 Fossorial Open water Chiromantis petersi 202 Arboreal Open water