The importance of frogs to the livelihood of the Bakossi people around Mount Manengouba, Cameroon, with special consideration of the Hairy Frog, Trichobatrachus robustus

2008·4.4 MB·English

by  Gonwouo, L N

Th e importance of frogs to the livelihood of the Bakossi people, Cameroon
SALAMANDRA 44 1 23-34 RRhheeiinnbbaacchh,, 2200 FFeebbrruuaarryy 22000088 ISSN 0036-3375
Th e importance of frogs to the livelihood of the Bakossi
people around Mount Manengouba, Cameroon, with special
consideration of the Hairy Frog, Trichobatrachus robustus
Legrand N. Gonwouo & Mark-Oliver Rödel
Abstract. Amphibians are harvested for various purposes around Mount Manengouba including food,
international pet trade and cultural reasons. At least seven frog species are regularly collected and con-
sumed: Conraua crassipes, C. goliath, C. robusta, Trichobatrachus robustus, Astylosternus spp., Xenopus
amieti, Kassina decorata. Over-exploitation of C. robusta for food and T. robustus for the international
pet trade, in addition to the harvest of tadpoles for human consumption, is currently increasing and
expected to have negative eff ects on wild populations. Th e males of the Hairy Frog, T. robustus, locally
known as “Ebod” are viewed upon by locals as being mystical. It is believed that these frogs fall from the
sky, and that childless human couples can turn fertile aft er having eaten this frog. All interviewed locals
declared to have once eaten a frog, while only 70% of them knew about the cultural signifi cance of the
Hairy Frog. Collection of any frog species is undertaken all year round but peaks in the dry seasons (both
for food and pet trade). Prices for two large or three medium-sized individuals of C. robusta are US 2
at the local food markets, while pairs of the Hairy Frogs are sold for US 8 to the international pet trade.
We discuss the need to set up plans for the sustainable harvest to maintain viable populations of these
species in the region.
Key words. Amphibia, Anura, ethno-zoology, food, harvesting, medicine, mountain streams.
Introduction as pests to crops and disease vectors to hu-
mans (Behangana & Arusi 2004). Th e sus-
Considerable eff orts have been made in sur- pension feeding larvae may play an impor-
veying the amphibian fauna of western Cen- tant role in the balance of aquatic systems by
tral Africa and clarifying their distribution regulating algal growth (e.g. Dickman 968,
and taxonomic status (e.g. Schiøtz 999, Seale 980, Wassersug 984, Osborne &
Perret 966, Amiet 975 and many other McLachlan 985, Whiles et al. 2006) and
papers, Lawson 993, LeBreton 999, Rö- by being important prey sources to aquatic
del et al. 2004). In contrast, little eff ort has invertebrate and vertebrate predators (Hey-
been undertaken to investigate the economic er et al. 975, Gascon 989, Rödel 999).
and cultural importance of frogs in this regi- Oft en adults are food for other vertebrates
on, although several species are known to be such as fi shes, snakes, birds and mammals
culturally and economically important (e.g. including humans (reviewed by Toledo et
Pauwels et al. 2003). al. 2007). Amphibians and reptiles have long
Amphibians are abundant in many eco- been used by humans as food (e.g. Walker
systems and serve as important links in eco- 966, Gibbons 2000) and medicine (e.g. Kl-
logical food chains, being both predators emens & Thorbjarnarson 995, Van Dijk
and prey (Duellman 990). As adults, they et al. 2000). Nowadays, some species are seen
are primary and secondary consumers of as attractive characters in commercial adver-
small animals, i.e. mainly arthropods at vari- tising and others are collected or bred for the
ous stages, many of which are well known international pet trade.
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Legrand N. Gonwouo & Mark-Oliver Rödel
Numerous cultures worldwide believe west Cameroon, some amphibians are eco-
that amphibians have mystical powers and nomically important, others are tradition-
are hence used in various rituals (Hofrich- ally pleasing (e.g. Trichobatrachus robustus
ter 998). Ancient cultures in Egypt, Greece, Boulenger, 900, Conraua robusta Nieden,
Turkey and Italy used frog amulets for good 908) to the Bakossi people and as such rep-
luck or to protect from evil and such practices resent a signifi cant entity to the livelihood of
continue to the present day (K. Adler 2007: the local human population. Th e Hairy Frog,
Amphibians and humans. – http://www.an- Trichobatrachus robustus, is native to this
swer.com/topic/amphibians-and-humans area, used for various purposes and hence of
[last inquiry:  March 2007]). Other beliefs cultural and economic signifi cance to the Ba-
focus on the connections of amphibians to kossi people. It is collected by young Bakossi
water, rainfall and earth. Besides their eco- for commercial and domestic purposes alike.
logical and cultural values, sometimes frogs Th e unregulated harvesting of these frogs is
constitute one of the main sources of proteins likely to have a negative impact on the natu-
regularly eaten by many indigenous peoples, ral populations.
especially in impoverished societies. Parti- Th is work was motivated in part by emerg-
cular species are collected in large numbers ing evidence that over-collecting of some
and over-collecting may lead to local extinc- frog species may result in the decline or ex-
tions or severe population declines. Th is is tinction of particular amphibian species and
especially important if frogs are collected for hence as well in the loss of the cultural beliefs
non-autochthonous use. For example, du- for which these species play an important
ring 998–2002, the United States imported role in the region. Th us, the data presented
4.7 million wild-caught whole amphibians herein aim to provide a fi rst contribution to
(Schlaepfer et al. 2005). Truong (2000) re- the knowledge of the economic and cultur-
ported that  Vietnamese amphibian species al value of the amphibian in a Cameroonian
of economic value have become rare, some mountainous region.
being even in danger of extinction, due to
over-exploitation. As many amphibian spe-
cies predictably aggregate for reproduction Materials and methods
or hibernation, this makes them particularly
vulnerable to intensive collecting eff orts. Re- Th is study was carried out around Mount
cent studies have indicated that commercial Manengouba in western Cameroon (N 05°02’,
or subsistence harvesting has contributed to E 09°50’). Th e Kupe-Manengouba and Bako-
a decline in many reptile species (e.g. Kle- ssi mountains comprise some of the wettest
mens & Thorbjarnarson 995, Van Dijk et forests in Africa. Mount Manengouba has a
al. 2000, Webb et al. 2002). Comparative fi - well developed tropical mountain cloud for-
gures for amphibians seem to be rare or la- est environment that extends to the Eboga
cking. Inappropriate exploitation of amphibi- caldera at ,800 m a.s.l. Th e peak of Mount
ans may increase the already desperate situa- Manengouba is at 2,4 m a.s.l. Th e caldera
tion of many amphibian populations, already possesses two volcanic lakes (,950 m a.s.l.)
in decline because of habitat destruction and in the middle, with the bigger being 600 m
degradation, global warming, and disease across. Th ere is some forest on the edge of
(Stuart et al. 2004, Lips et al. 2005, Pounds the two lakes but mainly on the south-east-
et al. 2006). Th e extent of exploitation of am- ern rim of the craters. Fulani herdsmen in-
phibians depends upon their distribution habit the crater (Fig. ). Th ey use the area as a
and the demands both of local people and of winter grazing ground for cattle, sheep, goats,
the international market. and horses. During the late dry season burn-
In the Manengouba region of South- ing of the grassland is practised. Primary for-
24
Th e importance of frogs to the livelihood of the Bakossi people, Cameroon
est extends down the slopes on the southern
fl ank to an altitude of ,500 m above the vil-
lage of Nsong. Th e mid-altitude forest in the
south-east of the mountain is drier than the
forest higher up. Th e forest on the slopes is
intact except near the village of Nsong and
the eastern slope to Nkongsamba where ag-
ricultural encroachment has extended locally
to the altitude of ,700 m a.s.l. (N 04°59’, E
09°52’). Th e southern slopes of the mountain
are still well forested down to around ,200
m a.s.l. at Manengouba village. Amphibians
primarily inhabit the numerous mountain
Fig. 1. Th e Eboga caldera on Mount Manengouba,
streams of various sizes. Th e rainy season in
Cameroon. Fulani herdsman campsites (in the up-
the area extends from March to October. per left half of the caldera) and swampy areas at
Between August 2005 and December 1,800 m a.s.l. Th ese areas are the main habitats of
2006, we gathered data on the economic and Xenopus amieti and Kassina decorata.
cultural importance of amphibians. Th is sur-
vey was mainly conducted on the western people from Ebonemin and fi ve people each
and southern fl anks of the mountain with six in the remaining fi ve villages. Th e interview-
villages visited: Belo, Ebonemin, Manengou- ees’ age ranged from 8 years (youth) to 66
ba, Moeba, Mouandong and Nsong. Visits to years (elders of the village) and included 2
these villages were undertaken during eco- women and 2 men.
logical surveys in the region. During these Firstly, the aim of the survey was briefl y
surveys the company of local guides from explained to the potential interviewee. If they
every village made possible discussions on wished to participate in the interview we pro-
the importance and cultural signifi cance of ceeded with the questioning. During the dis-
amphibian species to villagers. Th is informa- cussions respondents were asked a series of
tion was the basis for further questions. Data questions, including:
were collected by means of informal inter- . Do you know frogs and which are the
views and discussions including the topics: ones you eat?
use, knowledge and signifi cance of particular 2. Have any of these frogs got signifi cance
amphibian species to the local people. Th is to you/your tribe?
also included the preservation and transmis- 3. For what other reason do you collect
sion of the cultural information about these frogs?
animals to the young generation. Interviews 4. For whom do you collect and how oft en
were usually conducted in pidgin English do you collect during the year?
and generally in the presence of the respec- 5. What diffi culties do you encounter while
tive village guide, as interviewees were more performing this activity?
confi dent to talk openly in the presence of Identifi cation of species eaten or collect-
someone they know. Participants were ran- ed for the trade were clarifi ed with the aid of
domly chosen on the basis of the order in specimens previously collected during our
which they were met as we walked through ecological survey and shown to interviewees.
the village visiting compounds. Only one Alternatively we checked and determined the
person per family was interviewed and only specimens collected by the villagers. Ques-
those people who were willing to participate tions were asked in a non-leading way, but
were included in the survey. Interviews were yes/no type answers were discouraged. Re-
conducted with 33 people, including eight sponses were recorded during or immedi-
25
Legrand N. Gonwouo & Mark-Oliver Rödel
ately aft er the discussion. Interviews took and 36% women), knew or have heard of the
place generally between 5 p.m. and late in the cultural signifi cance of the Hairy Frog. Men
night, aft er the villagers had come back from generally were more likely to have this tradi-
their daily occupations. tional knowledge than women. We recorded
also some diff erences between villages, e.g.
whereas all interviewees from Moeba knew
Results about the Hairy Frog’s traditional use, only
General results 40% of the Manengouba people could posi-
tively answer this question (Table 2).
Local people around Mount Manengouba
proved to have a detailed knowledge of the
seasonality, ecological relationships, cultur- Collection for food
al attributes and uses of various frog species
found in this region. At least seven species of Th e collection of frogs for local consumption
frogs are regularly collected and consumed takes place all year round but generally, har-
including Conraua crassipes (Buchholz & vest peaks in the dry season when the levels
Peters, 875), C. goliath (Boulenger, 906), of the streams and ponds are low and collec-
C. robusta, Trichobatrachus robustus, Astylo- tion is easy. Frogs are continuously collected
sternus spp., Xenopus amieti Kobel, du Pas- by the villagers randomly during various dai-
quier, Fischberg & Gloor, 980, and Kas- ly activities. More organized collection tech-
sina decorata (Angel, 940). Th ese species niques include night search for large frogs in
inhabit quite diff erent habitat types ranging streams. Th is harvest technique is underta-
from primary forest along fast moving large ken by individuals or groups (generally four
streams (C. goliath, C. robusta, T. robustus) young men) along streams with fl ash lights to
to stagnant waters in montane grassland (X. locate the animals. Machetes, spears, hooks,
amieti, K. decorata). Th e former three species and nets are used to catch and kill the frogs.
are called “Essalle” in the local language with Th is method was practiced in all the villa-
no linguistic distinction of species (for ex- ges visited. Collectors slowly move upstream
ception see below). People from each of the while observing rocks and logs in the water.
villages collect these species for food or other All frogs found are cut or speared. Conraua
purposes (Table ). Th e frogs were consumed species are located at waterfalls and rapids
at various stages ranging from tadpoles to and are easily harvested by using nets. Nets
adults (Figs. 2, 3). All interviewees confi rmed are generally set up across the whole width
to have eaten frogs at least once. Collection of a stream, normally at sites where abun-
of tadpoles for consumption was random and dant frog populations are known to occur.
may include individuals of other species re- Th e net is held in position by wooden fl oats
producing in fast moving streams (allocable and anchored into the ground using wooden
to the genera Cardioglossa, Phrynobatrachus, sticks or stones. During the hunt two people
Leptodactylodon), as well as tree frogs. are positioned close to the net, carefully ob-
Of all the species consumed in the region, serving it, while two others move upstream,
the Hairy Frog, T. robustus, whose males are using long wooden sticks and spears to ex-
of particular interest as they have a cultur- plore holes within rocks in the streams and
al signifi cance to the people and are locally the river banks. Th ese activities chase frogs
known as “Ebod” (Fig. 4). Th is species also downstream where they are intercepted by
serves as an income-generating species to the the net and subsequently killed. According
youth of the area (< 30 years), who oft en col- to the local hunters this is the most rewar-
lect it for the international pet trade (Table ). ding method for frog hunting as up to 70 in-
Seventy percent of all interviewees (64% men dividuals can be collected during one night.
26
Th e importance of frogs to the livelihood of the Bakossi people, Cameroon
Tab. 1. Number of interviewed people according to age class, gender (men/women) and village and
reason of collecting frogs. F = Food, LT = Local Trade, IT = International Trade, CV = Cultural Value.
Village / age total 0 – 9 20 – 29 30 – 39 40 – 49 50 – 59 60 – 69
Belo 4 /   / 0 2 / 0 0 / 0 0 /   / 0 0 / 0
Ebonemin 4 / 4 0 / 0 0 / 0 2 / 2  / 0 0 /   / 
Manengoubaaa 3 / 2 0 / 0 3 / 0 0 / 2 0 / 0 0 / 0 0 / 0
Moeba 2 / 3 0 / 0  / 0 0 /   / 2 0 / 0 0 / 0
Mouandong 5 / 0  / 0  / 0 2 / 0 0 / 0  / 0 0 / 0
Nsong 3 / 2 0 / 0  / 0 0 / 0 0 / 0  / 2  / 0
total (N= 33) 2 / 2 2 / 0 8 / 0 4 / 5 2 / 3 3 / 3 2 / 
Collection purpose F, LT, IT F, LT, IT F, LT, CV F, LT, CV F, LT, CV F, LT, CV
Hunting without nets by directly killing frogs harvest for their immediate needs aft er rea-
with machetes and spears are less labor in- ching an agreement.
tensive but also less rewarding as hunters of- Another form of diurnal frog collection is
ten miss frogs that immediately jump into generally practiced by women. Th is especial-
the stream and swim away at the fi rst glance ly concerns the collection of tadpoles, ear-
of fl ashlights. ly in the dry seasons when the levels of the
Th e largest species in the area is C. goliath, streams and ponds are low. Th is form of hun-
which seems to be rare in the Manengouba ting is practiced on fast moving streams by
area. Th e most abundant species is C. robus- using basket traps made from rattan palm.
ta. Two hours of spotlight night walk along Th ese basket traps are conical with a roun-
a stream near the village of Manengouba II dish base. Th e trap is anchored to the stream
permitted us to locate 6 individuals of this bottom and held by one foot in such way that
species. Th is species is very much apprecia- water fl ows through the trap. Th e women try
ted by many indigenous people as it is hun- to turn over all rocks and logs in the stream
ted and immediately sold fresh in the local by hand (Fig. 6). Th e tadpoles then usual-
markets (Fig. 5). However, the demand has ly swim downstream and get intercepted in
always been greater than the supply in re- the traps. Th e traps are periodically removed
cent years. Large quantities of C. robusta are from the stream and all tadpoles and fresh-
harvested and sold on the local markets of water crabs are then transferred into another
Mouandong and Belo, which are held wee-
kly. Conraua robusta meat is highly prized
with three medium sized or two large indi- Tab. 2. Knowledge of the traditional use of the
Hairy Frog, according to village and gender (M =
viduals being worth ,000 CFA (about US
men, W = women) of the interviewees (compare
2), respectively. For special ceremonies such
Tab. 1).
as traditional weddings, Christmas, or New
Year celebrations, these frogs are demanded Village yes no Yes (%) No (%)
by villagers, and young people go hunting M W M W
them. Since these animals are of high value
Belo 3   0 80 20
to people in the region, frog hunting is gene-
Ebonemin 4 3 0  88 2
rally forbidden to non-natives. Every hunter
collects only in his village. Regulation of ac- Manengouba 2 0  2 40 60
cess to streams for hunting is granted by the Moeba 2 3 0 0 00 0
elders of the villages. Th ese elders can also Mouandong 3 0 2 0 60 40
give permission exceptionally to visitors to Nsong 2 0  2 40 60
27
Legrand N. Gonwouo & Mark-Oliver Rödel
Fig. 3. Kassina decorata tadpoles, collected for
consumption.
Fig. 2. Villager with frogs collected for food. He
has a Conraua goliath in his right and several C.
robusta in his left hand (C. robusta also on the leaf
on the bottom).
basket (Fig. 7). Th is is continuously repeated
while moving upstream until suffi cient tad-
poles have been collected. During this pro-
cess, all adult frogs of the consumed species
are killed and collected as well.
Adults and tadpoles are also collected in
large numbers by women when they block
one side of a diverging stream. Th is dries up
one part of the stream. Th ere all stones are
Fig. 4. Adult male of the Hairy Frog, Trichobatra-
subsequently turned over in search for hid-
chus robustus.
den frogs and tadpoles. Women also collect
tadpoles and adults of X. amieti and K. de-
corata in stagnant water bodies around the
caldera twin lakes. In the caldera lakes and
in larger streams fl owing close to the villages, smoked. For smoking, frogs are placed on a
clawed frogs are netted in huge numbers as grille above the fi re or hung above the fi re
seasonal supplements to human diets. Hun- aft er spearing them onto a rattan stick. Th e
ting there also generally takes place during most famous and appreciated meal prepared
the early dry season (November, December) with smoked frogs is called “Mpup”. Th is is
when the water level is low and the tadpo- a pudding, made from dried and crushed
les are concentrated in small remaining wa- plantains (bananas used for cooking) mixed
ter bodies. with slices of smoked “Essalle”. Th e “Mpup”
is eaten with crushed cocoyams (“Essobah”)
and a famous black soup made from crushed
Preparation leaves of another cocoyam variety (“Quan-
qualang”). “Mpup” is oft en served during tra-
Th e preparation of “Essalle” varies but in- ditional wedding ceremonies (i.e. to in-laws)
dividuals are usually eviscerated and then and during other feasts.
28
Th e importance of frogs to the livelihood of the Bakossi people, Cameroon
Fig. 5. Conraua robusta collected and sold for local
consumption.
Fig. 7. Tadpoles (predominantly Astylosternus and
Conraua) and freshwater crabs harvest for food
(see Fig. 6).
Fig. 6. Women collecting tadpoles for consump-
tion in mountain streams (see Fig. 7).
International trade
Fig. 8. Life Trichobatrachus robustus collected for
the international pet trade.
In the Bakossiland the collection of frogs for
the international trade started less than 0 ye-
ars ago and is on the increase. It is an activity season when frogs are also easier to collect
exclusively conducted by youths of less than (see above). During the dry season orders are
30 years old (Table ). Th e most commonly normally fi lled within 0 to 24 days, during
collected frog for sale is T. robustus (Fig. 8). the rainy season this takes longer.
Th ese frogs are usually delivered to the dea- Hairy frogs are collected during the day by
lers alive and in pairs. Orders vary from 0 turning over large rocks and logs. Nets placed
to 5 pairs and dealers generally refuse to downstream are used to intercept the frogs.
take old females as these no longer reprodu- Blocking water at diverging points is also
ce. Individuals are sold for US 4 each: Half practiced while collecting T. robustus. Coll-
of the price is paid in advance (before coll- ected animals are stored in large drums and
ecting the frogs). According to locals, orders buckets with some water until the arrival of
for frogs are commonly received in the dry the dealers. Collectors check animals every
29
Legrand N. Gonwouo & Mark-Oliver Rödel
day and those that die are removed and ea- used as a local food source and collected for
ten. On 20 November 2006, we observed 20 the international pet trade. Other frogs like
individuals of T. robustus (0 males and 0 fe- various Conraua species and their tadpoles
males), collected by a young man at Belo vil- are collected as well, but exclusively for local
lage. Our interview revealed that he had re- consumption. While T. robustus still seems
ceived an order from a dealer from Douala. to be abundant in the region, the world’s lar-
Demands generally originate from Limbe, a gest frog, C. goliath, seems to be rare. We do
town on the Cameroonian coast, or Douala. not know if this species has been always rare
around Mount Manengouba or if the present
populations are already reduced due to ove-
Cultural use and value rexploitation. Wild et al. (2004) reported
that C. goliath is present up to 700 m a.s.l. in
In addition to the usage of Hairy Frogs as a the eastern tributaries of Kupe and Manen-
protein source and the collection for the in- gouba which drain into the Dibombe River
ternational pet trade, traditional people have in the Littoral Province. Our sites were above
a strong relationship to the male T. robustus. 000 m a.s.l. Th is and the fact that our study
Th ey believe that the frogs fall from the sky region is the western distribution limit of the
during heavy rains. Fallen frogs are thought species, likely are further reasons for the rari-
to be found along footpaths in the forest, on ty of C. goliath.
plantation roads or in torrent water. Th e spe- Frog and tadpole hunting by local peo-
cies is believed to have mystical powers, and ple was common around the study site and
serves as an indicator of good luck. Th e most as far as tadpoles are concerned was not spe-
signifi cant attribute of the mystical power of cies-specifi c. Recent studies on the herpeto-
this frog is its ability to turn sterile couples fauna of the Korup National Park (Lawson
fertile. If a childless couple happens to coll- 993) and Mount Nlonako (Herrmann et
ect this frog during the heavy rains and sub- al. 2005), both located in Cameroon, also re-
sequently consume it, the wife will certainly vealed that C. robusta and T. robustus were
conceive if sex is practiced during the day of frequently consumed. Th e hunting pressure
collection. Th e frog must be consumed only around the villages surveyed by us was very
by this couple. It is also indispensable that the intense and women oft en undertook special
frog has been found by one of the partners trips to distant, heretofore unhunted streams
and not by a third person. However, for any to collect the frogs. Th is is a sign that the cur-
person collecting the frog during the rains or rent collection is over-exploiting the natural
incidentally on the plantations while clearing populations as nearby streams no longer of-
or other collective farming activities, then for fer a suffi cient harvest. Th is is also suppor-
her or him this is a defi nite positive sign for ted by hunters who indicated that collection
life. Th e meaning may range from “your wife is more successful in streams that are distant
becoming pregnant” to “having the best har- from the villages. In the Nigerian Oban pla-
vests of coff ee, cocoyam, plantains etc. in this teau, where tribes related to the Bakossi peo-
season.” ple live, the same hunting techniques are
used to collect frogs. Th ere women frequent-
ly have to walk long distances to collect tad-
Discussion poles and adult frogs (A. Onadeko & M.-O.
Rödel unpubl. data). Th e low densities of C.
To our knowledge here we report for the fi rst robustus and T. robustus around the villages
time the traditional medical use of an Afri- likely is the result of the simultaneous coll-
can frog, namely T. robustus as a cure for ste- ection of both adults and tadpoles. A severe
rility. Additionally, this species is commonly impact on tadpoles may ultimately result in
30
Th e importance of frogs to the livelihood of the Bakossi people, Cameroon
even more critical changes in the population as a result of such practices and they even-
structure than collecting adults only (Heyer tually likely die, thus increasing the death
973, Wilbur 980). However, collecting ef- toll. Canalization of mountain streams and
fects may be especially dramatic when bree- turning over all rocks within these stream-
ding aggregations form predictably at the beds greatly modify the environment more
same sites. In some amphibian species it is frequently and during other periods (dry in-
known that aggregations move from year to stead of core rainy season) than natural, not
year (Marsh et al. 999). As in our region only for frogs and tadpoles but also for other
whole streams were regularly checked and aquatic organisms.
harvested for frogs, it is likely that all focus Th e collection of amphibians in the region
species are equally aff ected. is further enhanced by the international pet
We do not know to what extent, or if at all, trade, at least as it concerns T. robustus. It is
the mentioned frog populations are already known with regard to reptiles that removing
over-exploited and what natural population even a small fraction of adults can bring a po-
sizes would be. However, on Mount Manen- pulation to decline (e.g. Klemens & Thorb-
gouba amphibians are not only prone to col- jarnarson 995). Collecting frogs for the pet
lection but in addition face various adverse trade at Mount Manengouba is a tradition of
environmental impacts (logging, agricultu- less than 0 years but is likely to expand in the
ral encroachment, overgrazing, water pollu- years to come. Locals have previously been
tion by use of pesticides, etc.). Th us, further collecting chameleons in the area for the pet
negative impacts on the growth of tadpoles trade and recent investigations revealed the
and adult survival are likely. Th e cumulative population of one of the highly desired spe-
eff ects of commercial exploitation and ha- cies (Chamaeleo pfeff eri) has dropped drasti-
bitat loss on reptiles have been discussed by cally (Gonwouo et al. in press). Th is could
Gonwouo et al. (in press). It is known that be one of the reasons why local collectors are
the decline of amphibian populations may switching to frogs, which seemingly generate
have severe eff ects on Neotropical stream the same income, but are less time intensive
systems (Whiles et al. 2006), but comparab- to collect. As with the chameleons, the po-
le data are so far lacking for Africa. Th e ex- pulations of T. robustus now seem to be re-
tent to which amphibians could be harvested duced as collectors have to move further and
without overexploiting them depends upon further to encounter them. Collection is usu-
such variables as their reproductive potential, ally done for everybody who passes by and is
their specifi c life histories, their distribution willing to pay, and is generally done without
and accessibility. Unfortunately, most of the- export permits. None of the persons inter-
se data are still lacking even for the few most viewed had ever knowingly collected for dea-
commonly harvested frog species. However, lers with an export permit.
based on reports by local people on the dif- Trichobatrachus robustus is a species that
fi culties to fi nd the animals, frogs seem to be people of the Manengouba area value more
rarer now than in the recent past. than other members of the local fauna. Th is
More sustainable hunting of frogs in the relationship is based on inherited beliefs. Th e
future should not only take into considera- origin of their belief that frogs of this species
tion population dynamics, but would best fall from the sky is not yet understood, but
also alter some of the techniques used. Th ese may be linked to the migration behavior of
techniques are oft en harmful to the animals this frog, being terrestrial during non-repro-
as well as the environment. Th ese include ductive periods and aquatic during repro-
hooked sticks, oft en used to pull frogs from duction (e.g. Lawson 993). Insofar as the
water and their hiding places under rocks. frogs really help curing a childless couple is
Many animals are injured but not collected unknown. However, this belief seems to be
31
Legrand N. Gonwouo & Mark-Oliver Rödel
long-standing. nerations. Nevertheless, elders of the region
Th e ongoing social and economic changes are already aware that social changes in the
in the Manengouba region, including habitat region over the last two decades, and parti-
destruction and the collection of T. robustus cularly more recently, impact the extent to
for the international pet trade, may fi nally which cultural knowledge and practices are
result in the local extinction of this species passed on. Th ese changes include the practi-
and hence in the extinction of a local tradi- cing of more sedentary lifestyles resulting
tion. Th e Mount Manengouba area has re- from increasing formal education opportu-
cently been recommended to the Ministry nities, access to modern medicine and to va-
of Forestry and Wildlife and the Ministry of rious media such as radio, television, and in-
Culture as a World Heritage Site on the basis ternet. However, some of these changes may
of the cultural values of numerous traditio- also contribute positively to the maintenance
nal societies (Wild et al. 2003). Developing of cultural values, through cultural lessons at
sound conservation management programs school, if incorporated into the history of the
for frogs and other components of the uti- region.
lised biological diversity, while integrating Improved education of custom inspectors
the needs of the local populations, should and more frequent inspections may aid in
help to save these cultural practices. limiting the illegal pet trade. Th ere are also
opportunities for the Bakossi people to con-
tribute positively to the maintenance of their
Conclusions cultural values. Th is includes the regulation
of commercial collection of species by young
Although the trade of amphibians provi- people. Th is issue can be addressed by village
des a valuable source of revenue to locals, its elders in collaboration with traditional chiefs
practice is uncontrolled and likely to have an and appropriate organizations, through the
important and negative impact on the natu- development of strategies and actions to mi-
ral populations of particular frog species. As nimize and monitor the impact of the activity
long as the demand is high and buyers are on wild populations. A detailed study of the
willing to purchase a wild-caught amphibian, natural history of T. robustus could certainly
the trade will surely continue. Educating the contribute to the development of sustainable
public on laws and ecology may reduce some harvesting plans. Th ese strategies and actions
of this demand. It is essential to control the could form part of the proposed Cultural He-
level of exploitation to allow sustainable long- ritage Management Plan already initiated by
term benefi ts to the local population, e.g. by the CRES-WWF projects.
collecting only for dealers with valid export
permits. Respective activities may contribu-
Acknowledgements
te to protect amphibian populations around
Mount Manengouba against the danger of a Th is study was made possible with funds from
rapid decline. At the same time, these are also Conservation International, Washington D.C. th-
a basis for the sustainable maintenance of the rough Don Church to whom we are very grate-
cultural value of some species, i.e. T. robustus. ful. Th anks are also due to the Cameroonian Go-
Traditional owners stressed the importance vernment through the Ministry of Forestry and
Wildlife (MINFOF) which issued and renewed re-
of maintaining the cultural values within
search and collecting permits for this study and
their clan groups and within the broader Ba-
to our local guides for their excellent work. We
kossi society. Knowledge of the usage of frogs
particularly thank the people of the Manengouba
and other cultural attributes are currently wi- area who readily took part in this study. An ano-
dely held by people in the Bakossi region and nymous reviewer provided valuable comments to
this information is passed on to younger ge- an earlier version of the manuscript.
32