Corresponding author: Mark-Oliver Rödel (
Academic editor: Johannes Penner
In March and April 2018 we surveyed amphibians and reptiles in two Proposed Protected Areas (PPAs) in Liberia. In the Krahn-Bassa Proposed Protected Area (
This study also emphasizes that the western part of the Liberian forests comprise at least partly a herpetofauna which differs from that of the East of the country. The recorded threatened amphibian species are all specialized on relatively undisturbed rainforests and they all have only small geographic ranges. The remaining parts of undisturbed or little disturbed forests thus have high importance for the long-term survival of these species. In conclusion the study areas have a high conservation potential and should be urgently protected from any further forest loss degradation and uncontrolled hunting.
Amphibians and reptiles are amongst the world’s most endangered organisms. Reasons are manifold, but the most important ones are unarguably habitat destruction, conversion, and fragmentation, presumably followed by pollution, disease and climate change (
Compared to neighboring Côte d’Ivoire, the herpetofauna of Liberia is only poorly known, although herpetological specimens from Liberia have been reported as early as the beginning of the last century (
These early discoveries were followed by a longer period without any herpetological data from Liberia. Liberia was always hard to access due to the lack of infrastructure such as roads in most parts of the country, but from 1989–2003 a particularly brutal civil war stopped all scientific exploration within the country. Only in 2005, on a Rapid Assessment organized by Conservation International, Annika Hillers surveyed amphibians and reptiles in three Liberian forests, reporting five frog species new for the country (
Both study areas were surveyed during the beginning of the rainy season. The Krahn-Bassa Proposed Protected Area (
Details on study sites in the Krahn-Bassa (
Area | Date | Time of day | Person/ hours | Site details | latitude (N) | longitude (W) |
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24.03.18 | morning | 08:00 | Closed forest parallel to small stream |
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24.03.18 | afternoon | 13:00 | Closed forest parallel to small stream |
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24.03.18 | night | 08:00 | Closed forest |
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25.03.18 | morning | 15:00 | Closed forest |
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25.03.18 | night | 08:00 | Closed forest |
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26.03.18 | afternoon | 08:40 | Closed forest parallel to small stream |
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26.03.18 | night | 07:00 | Closed forest |
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28.03.18 | night | 07:00 | Closed forest parallel to large river |
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29.03.18 | morning | 16:00 | Closed forest parallel to large river |
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29.03.18 | night | 11:40 | Closed forest |
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30.03.18 | afternoon | 10:00 | Closed forest |
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30.03.18 | night | 09:00 | Closed forest and gold mining pits |
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31.03.18 | morning | 16:00 | Closed forest parallel to large river |
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31.03.18 | night | 04:00 | Closed forest and gold mining pits |
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04.04.18 | night | 08:00 | Closed forest along small stream |
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05.04.18 | morning | 14:00 | Closed forest |
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05.04.18 | night | 14:00 | Closed forest |
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06.04.18 | morning | 19:00 | Closed forest along small and large streams, including cascades |
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06.04.18 | night | 12:00 | Closed forest along small and large streams, including cascades |
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07.04.18 | night | 07:00 | Along road and cocoa plantations |
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08.04.18 | morning | 18:00 | Closed forest, along stream including cascades |
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08.04.18 | night | 08:00 | Closed forest, along stream including cascades |
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09.04.18 | morning | 10:00 | Closed forest and along streams |
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09.04.18 | night | 05:20 | Closed forest and along streams |
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The Foya Proposed Protected Area (
Natural and disturbed habitats in the Krahn-Bassa (
Amphibians and reptiles were recorded during visual and acoustic encounter surveys by four people. The surveys were undertaken during day and night. Searching techniques included visual scanning of the terrain and investigation of potential hiding places or very specific habitats (e.g. tree holes, small rivers, and waterfalls); for tadpoles we searched by dip-netting in all available potential breeding sites (
Our sampling design only provided qualitative and semi-quantitative data. We therefore calculated the estimated species richness and, hence, our sampling efficiency with the Jackknife 1 and Chao 2 estimators using EstimateS (
The nomenclature for amphibians follows
Numbers listed in brackets after study site abbreviations refer to voucher specimens (
Amphibian species recorded in Krahn-Bassa Proposed Protected Area (
Genus | Species | # |
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pf | df | oh | wUG | UG | wA | A | IUCN |
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5 | 1 | 1 | 1 | LC | |||||
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2 | 1 | 1 | LC | |||||||
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5 | 1 | 1 | 1 | LC | ||||||
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‘albolabris West’ | 7 | 6 | 1 | 1 | 1 | NE | ||||
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1 | 1 | 1 | EN | |||||||
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sp. 1 | 8 | 3 | 1 | 1 | 1 | NE | ||||
sp. 2 | 4 | 3 | 1 | 1 | NE | ||||||
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2 | 4 | 1 | 1 | LC | |||||
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1 | 1 | 1 | 1 | LC | |||||
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5 | 5 | 1 | 1 | NE | |||||
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6 | 3 | 1 | 1 | LC | |||||
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2 | 6 | 1 | 1 | VU | |||||
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2 | 1 | 1 | 1 | LC | |||||
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2 | 1 | 1 | 1 | LC | |||||
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9 | 6 | 1 | 1 | NT | |||||
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1 | 2 | 1 | 1 | 1 | LC | |||||
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3 | 1 | 1 | LC | |||||||
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1 | 3 | 1 | 1 | 1 | LC | |||||
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7 | 2 | 1 | 1 | LC | ||||||
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1 | 1 | 1 | DD | |||||||
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1 | 1 | 1 | 1 | NT | ||||||
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6 | 6 | 1 | 1 | NT | |||||
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3 | 1 | 1 | 1 | NT | ||||||
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7 | 6 | 1 | 1 | 1 | LC | |||||
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3 | 1 | 1 | LC | |||||||
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3 | 1 | 1 | NT | ||||||
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3 | 1 | 1 | LC | ||||||
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7 | 4 | 1 | 1 | NT | |||||
'aff. |
2 | 1 | ? | NE | |||||||
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1 | 1 | 1 | 1 | LC | ||||||
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1 | 1 | 1 | LC | |||||||
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2 | 1 | 1 | NT | |||||||
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3 | 1 | 1 | 1 | 1 | LC | |||||
,sp. |
3 | 1 | ? | NE | |||||||
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1 | 1 | 1 | 1 | LC | ||||||
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7 | 5 | 1 | 1 | NT | ||||||
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1 | 1 | 1 | 1 | NT | ||||||
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8 | 1 | 1 | LC | |||||||
‘sp. Gola’ | 2 | 1 | 1 | NE | |||||||
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7 | 5 | 1 | 1 | 1 | LC | |||||
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2 | 1 | 1 | VU | |||||||
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6 | 1 | 1 | NE | ||||||
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1 | 3 | 1 | 1 | 1 | LC | |||||
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1 | 3 | 1 | 1 | 1 | LC | |||||
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1 | 1 | 1 | LC | |||||||
sp. | 6 | 1 | ? | NE | |||||||
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1 | 3 | 1 | 1 | 1 | LC | ||||
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2 | 2 | 1 | 1 | NT | ||||||
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2 | 4 | 1 | 1 | 1 | LC | ||||
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Three
An aquatic species of forests, degraded forests, and gallery forests in the moist savanna zone, which can be found from Senegal to western Cameroon (
Both direct developing species occur in forest (
This species lives in the leaf litter along small rivers in primary and slightly degraded forest from Sierra Leone to Ghana (
This species breeds in clear, in part fast flowing streams within the rainforest. However, adults may be also found at night in leaf litter far away from water. This species occurs in primary and slightly degraded forest of the western part of the Upper Guinea hotspot (
A very common small (males) to mid-sized (females) arboreal frog of degraded and primary forests. The quiet chucks and buzzes of adult males can be usually heard at night, a few meters up in dense vegetation near swampy areas (
This is a large arboreal frog with distinct black, parallel bands across the back (Fig.
This is a mid-sized treefrog of primary forest in the western part of West Africa, usually calling from a few meters up in trees, near swampy parts of the forest or forest ponds (
This is a savanna treefrog which enters the forest zone in areas where forest has been cleared (
This is a very common species in the savanna zone and heavily degraded areas in the forest zone, sometimes entering forest along logging roads (
This toad species lives in primary forests from Togo to Sierra Leone. It breeds in small forest streams, but adults may be found in the leaf litter in all parts of the forest (
This aquatic frog occurs in slow and fast flowing rainforest streams in the western part of the Upper Guinea forests (
This is a large, fully aquatic species, which is widespread in savannas and degraded habitats throughout tropical Africa (
This is a leaf-folding frog of the West and Central African forest zone. In gallery forest it usually ranges far into savanna areas (
This is a leaf-folding frog of the West African forest zone, where it lives in heavily degraded former forest (
This is a typical leaf-folding frog of primary closed canopy forest. The frogs are usually calling from high up in trees near forest ponds (
The calls of this treefrog are the most common nocturnal sounds along rivers in primary forests of the western part of the Upper Guinea forest zone (
This reedfrog lives in degraded parts of rainforest, as well as in humid savannas. It is absent from closed canopy forest (
This small reedfrog occurs in the rainforest zones of western Africa (
This is a reedfrog of the western African rainforest and southern savanna zone, where it usually lives in and around open ponds with densely vegetated banks. It avoids closed forest (
This reedfrog occurs in secondary growth and degraded forest habitats from Sierra Leone to central Ghana. It breeds in stagnant and slow flowing waters (
This reedfrog is only known from the western part of the Upper Guinea forest zone. It seems to be more closely associated with primary rainforest than the related
This reedfrog occurs only in primary forest (Fig.
This is a large treefrog of the western Africa forest zone and occurs at forest edges and along dense vegetation of larger ponds (
The sable-toothed frog was, in part, very common along rocky creeks and rivers in primary and slightly degraded forests of
This is a typical frog of primary and slightly degraded forests of the Upper Guinea forest zone (
These frogs are morphologically very similar to the previous species; however, adult males present distinctly different ventral coloration. These color differences are reflected by genetic differences (M.-O. Rödel and J. Glos unpubl. data). However, as
These frogs comprise a complex of cryptic species (
This is a species of degraded forest and forest edges in the western part of the Upper Guinea forest region (
This is a species specialized to breed in water-filled tree holes in rainforests (Rödel et al. 2004). It is currently known from western Côte d’Ivoire, south-western Guinea and eastern Liberia (
This species was originally described from Sanikolé, Liberia (
In drier parts of primary forest, near camp 1 in
This species occurs from heavily degraded rainforest habitats throughout all of West and western Central African savanna habitats into the southern Sahara (
This is a species typical for swampy primary forests, where they occur near slow-flowing, often very shallow streams (
This is a characteristic species of swampy primary forest from eastern Côte d’Ivoire to Sierra Leone (
This is a large species of
This species is morphologically almost identical to, but genetically different from,
This small leaf-litter frog is known from western Guinea to Ghana (
This is a very small leaf-litter frog, which is known to occur patchily from Ghana to Liberia in swampy parts of primary rainforest (
This is a typical rocket frog of leaf litter of lowland rainforests with terrestrial egg deposition (
This is a typical rocket frog living in savanna and degraded forest habitats, where it breeds in stagnant puddles and pools (
This forest frog prefers open areas and puddles on forest roads where they may congregate to large choruses (
This is a complex of rocket-frog species ranging across the whole of sub-Saharan Africa, Madagascar, the Seychelles, and the Mascarene Islands (
We found these frogs (Fig.
This is an aquatic frog, known to feed, amongst other prey, on small fish (
This is a median-sized to large leaf-litter frog which was believed to range from forested West Africa into western East Africa. Very recently
A large leaf-litter frog patchily distributed along rainforest streams of the Upper Guinea forests (
This is a complex of treefrogs which is widespread in West and Central African rainforests (
According to our guide, these large soft-shelled turtles use a particular sandbank of one large river as their breeding site in
We encountered an adult specimen (103 cm length) of this threatened dwarf crocodile at night, near a swampy part of primary rainforest in
These common rock- and tree-dwelling lizards (
This widespread West African forest gecko (
This is a widespread species in western African forests (
This is an arboreal lizard of West and Central African rainforests and occurs east to Uganda (
Water skinks were occasionally encountered in the leaf litter along small streams in primary forest of
This skink is frequently seen in clearings or degraded parts of the forest. This species-complex is widely distributed in forests (rainforest and the humid savanna zone) of West and Central Africa (
This skink is broadly distributed throughout Africa (
We observed adult specimens foraging during the day in the leaf litter of drier parts of the rainforest. The validity of this taxon was recently doubted, and it was consequently synonymized by
We collected at night in
In
We collected a stiletto snake at night in
We found a juvenile snake in a degraded area near a small stream in a cleared area surrounded by forest. This species is widespread in forest and savanna habitats in West Africa (
This West African species lives in leaf litter in rainforests (
In
This is a species of small arboreal viper, which is widely distributed in the Upper Guinea rainforests (Rödel and Masberg 2000;
In
In
Because our data for amphibians are much more complete than those for reptiles, we only analyse the former. We found at both sites combined a minimum of 49 amphibian species (1 caecilian, 48 anurans) but did not count cryptic species within, e.g., the
In
Permutated species accumulation curves (=sample-based rarefaction curve; red line: mean, blue lines: 95% confidence intervalls) of amphibian species richness in
In
Whereas we obtained a very good overview of the amphibian fauna, the reptile data are too incomplete to allow for meaningful discussions. We recorded a few interesting reptile species, but for snakes more than 50 species might be expected in both sites (e.g.
We recorded between 36 and 39 amphibian species at both sites, and we estimated the presence of another 15–20 species that we could not find. Compared to data available from other forest sites within the western part of the Upper Guinea forest region (
We found the amphibian and reptile fauna in
We conclude that both
We thank the Wild Chimpanzee Foundation and the Society for the Conservation of Nature of Liberia, their employees in general, and Annika Hillers and Jerry Garteh in particular for the invitation to conduct our survey and for all the logistic support! Without the various drivers, guides, porters, and cooks, the survey would not have been possible. Thank you all for your support! Alan Channing and Philipp Wagner provided valuable comments to a previous draft of the manuscript. Comments by Robert Forsyth improved the language. Finally, we thank the Forestry Development Authority (FDA) of the Republic of Liberia for the permission to survey these forests and the collection and export permits (Ref: MD/037/2018/11).