Local Knowledge and Use of Pangolins by Culturally Diverse Communities in the Forest-Savannah Transition Area of Cameroon

Information about the presence and population status of pangolins, and the threats they face, remains limited in many parts of Cameroon, a country that is home to three species of pangolin and considered to be a global hub of pangolin trafficking. Local communities living in rural areas can provide valuable information on species presence, local uses of wildlife, and possible threats, that is useful for prioritising conservation actions. Using interview surveys in 20 villages surrounding Mbam and Djerem National Park, we investigated local peoples’ knowledge of pangolin presence, perceptions of population trends, cultural importance, consumptive and non-consumptive uses, and hunting of pangolins. Our results showed that most people recognised the white-bellied and giant pangolins, but only 10% recognised the black-bellied pangolin. Ethnolinguistic group significantly affected the likelihood of respondents recognising and having seen a pangolin before. Giant pangolin populations were perceived to be declining, particularly by older respondents. We found evidence of local use of pangolins for meat, but few respondents reported uses of scales. Cultural significance was reported by few respondents, but when it was reported it mostly referred to giant pangolin. White-bellied pangolins are reportedly hunted using bare hands for local consumption most frequently, whilst giant pangolins were mainly hunted for local consumption and income generation using wire snares. Overall, our study shows the possible value of local knowledge for planning and prioritising conservation actions for pangolins. We highlight the urgent need to monitor pangolin populations, and assess the possible impacts to pangolins from threats such as hunting

Maximum entropy modeling of giant pangolin Smutsia gigantea (Illiger, 1815) habitat suitability in a protected forest-savannah transition area of central Cameroon

Across the planet, biodiversity is facing ever-growing threats including habitat loss, climate change, overexploitation, and pollution. Pangolins of the order Pholidota are the only scaly mammal species worldwide and are considered the most trafficked wild mammals in the world, being widely exploited for their meat and scales. The giant pangolin (Smutsia gigantea, GP) is one of the least studied species of this order, with little being known about their response to environmental and anthropogenic variables, as well as their distribution patterns in forest-savannah transition areas. Our study aimed to increase ecological knowledge about GP by investigating the environmental factors associated with the distribution of suitable habitat for GP within a protected forest/savannah transition area of Cameroon. Using data on the locations of GP resting burrows collected using line transects and employing a maximum entropy (MaxEnt) modelling approach, we explored GP habitat suitability within a forest-savannah transition area of Cameroon. Our model revealed a good level of accuracy based on the average test area under the Receiver Operator Curve metric. The jackknife test found that Euclidian distance to the national park’s boundaries, normalized difference vegetation index, elevation, and distance to river were the most important predictors determining the distribution of GP burrows. Areas predicted to be suitable for GP burrows were patchily distributed within dense forests, ecotone and savannah, with 19.24% of the study area being suitable and 1% very suitable. Overall, our study shows the possible importance of habitat suitability modeling for understanding GP distribution, as well as planning and prioritising their conservation actions

Reported incidence of manatee mortality in lakes (L), rivers (R), and coast & estuaries (C&E).

<p>The main features are that: (a) the number of sighted manatee carcasses increases downstream the lakes (with a peak in the rivers); (b) sighting three manatee carcasses or more associates highly with the sighting of four live manatees or more; (c) on average, one manatee carcass is sighted in all habitat types; however, such sightings are more frequent in the lakes and, to a lesser extent, in the rivers; (d) the incidence of catches increases from the lakes to the rivers and then to the coast & estuaries.</p

Map of the study area.

<p>Surveyed villages are displayed together with the manatee distribution; the two large circles indicate the reported manatee hotspots.</p

Mosaic plot of patterns in the sightings of dead manatees.

<p>The number of dead manatees ever sighted, D (0, 1–2, and 3+) reveals two patterns. Firstly, the sighting of three manatee carcasses or more (D3+) is strongly associated with the sighting of four live manatees or more (L4+). Secondly, the lower reaches of the rivers and the coast & estuaries are highly associated with the sighting of more carcasses.</p

Reported incidence of manatee mortality in lakes (L), rivers (R), and coast & estuaries (C&E).

<p>The main features are that: (a) the number of sighted manatee carcasses increases downstream the lakes (with a peak in the rivers); (b) sighting three manatee carcasses or more associates highly with the sighting of four live manatees or more; (c) on average, one manatee carcass is sighted in all habitat types; however, such sightings are more frequent in the lakes and, to a lesser extent, in the rivers; (d) the incidence of catches increases from the lakes to the rivers and then to the coast & estuaries.</p

Using Pooled Local Expert Opinions (PLEO) to Discern Patterns in Sightings of Live and Dead Manatees (<i>Trichechus senegalensis</i>, Link 1785) in Lower Sanaga Basin, Cameroon

<div><p>We aimed at unveiling patterns in live and dead manatee sightings in the Lower Sanaga Basin, Cameroon. For this purpose, the expert opinions of 133 local fishers were collected during in-person interviews, distilled using categorical data analysis, and checked against scientific literature. The five main results are as follows: manatees were sighted averagely once a week in lakes, rivers, and the coast & estuaries, mostly in group sizes of 2-3; the odds of sighting live manatees (respectively dead manatees) decreased (respectively increased) from inland lakes to estuaries and the coast, via rivers; manatee carcasses were reported in all habitats, albeit more frequently in rivers; a distribution map based on fishers’ reports show two manatee concentration areas: Lake Ossa and the Malimba-Mbiako section of River Sanaga; the number of manatees was perceived as increasing despite incidental and directed catches. Thus, our findings corroborate earlier assessments of the Lower Sanaga Basin as being a major manatee conservation area. Additionally, from these results and the literature, we identified three hypotheses about local manatee persistence: deep pools such as lakes offer year round sanctuaries, not just dry-season refugia; seasonality of specific habitat variables determine manatee occurrence patterns; and local variability in habitat encroachment mediate the meta-population dynamics of manatee in the Lower Sanaga Basin. Finally, we examine the implications for data requirements in light of the small ecological scale at which the surveyed fishers ply their trade. Thus, consonant with the Malawi principles for the ecosystem approach to management (<a href="http://www.cbd.int/ecosystem" target="_blank">www.cbd.int/ecosystem</a>), we recommend collecting data preferably at landscape scale, through a participatory monitoring program that fully integrates scientific and traditional knowledge systems. This program should include, amongst others, a standardised necropsy protocol for collecting mortality and biological data together with sonar and radio-telemetry technology to discern manatee use and movements between critical habitat components.</p></div

Mosaic plot of patterns in the sightings of live manatees.

<p>Live manatee sightings in rivers and coast & estuaries are most frequent in the evenings of the rainy season (Ry). In lakes, however, manatees seem to have a diurnal activity pattern in the morning of both seasons (Dy and Ry) and the midday-to- afternoon period of the dry season (Dy) as opposed to crepuscular-to-nocturnal activity pattern in the rainy season (Ry).</p