Using local knowledge and camera traps to investigate occurrence and habitat preference of an Endangered primate: the endemic dryas monkey in the Democratic Republic of the Congo
D ANIEL A LEMPIJEVIC,JOHN A. HART,TERESE B. HART and K ATE M. DETWILER
Abstract The Endangered dryas monkey Cercopithecus dryas, the type locality, description of Cercopithecus salongo as a endemic to the Democratic Republic of the Congo, is one of new species, and lack of specimens have led to taxonomic Africa’s most enigmatic primates. The discovery of a dryas confusion (Schwarz, ; Dandelot, ; Thys van den monkey killed by a hunter in the buffer zone of Lomami Audenaerde, ; Kuroda et al., ; Groves, ). National Park in prompted field research on the species’ Cercopithecus salongo specimens were eventually deter- distribution, habitat use and stratum preference. We used local mined to be the adult of the juvenile C. dryas type spe- knowledge to determine the distribution of this species and to cimen (Colyn et al., ), although this remains disputed select sites for camera-trap surveys in Lomami National Park (Sarmiento, ; Kingdon, ). Recent genomic studies and its buffer zone. We employed a multi-strata (– m) cam- have confirmed that the dryas monkey is a sister lineage era-trap placement technique to determine habitat use at Camp to savannah monkeys of the genus Chlorocebus, suggest- Bartho in Lomami National Park and Bafundo Forest in the ing the Cercopithecus group is paraphyletic (Guschanski Park’s buffer zone. We confirmed the occurrence of the dryas et al., ; van der Valk et al., ). Here we accept monkey at seven locations over a total area of , km ,inboth Chlorocebus as the appropriate generic affiliation, pending theParkanditsbufferzone.Dryasmonkeysweredetected further analyses of available specimens, and accept salongo most frequently (. events/ trap-days) in disturbed areas as a junior synonym of dryas (Gilbert et al., in press). The of Bafundo Forest and less in mature forest in Camp Bartho dryas monkey’s status as the only representative of the (. events/ trap-days). Dryas monkeys appear to prefer Chlorocebus clade found in lowland rainforest highlights structurally complex understories and forest edges. We found its high conservation value as an evolutionarily significant that camera traps at – mabovegroundoveratleast trap- lineage. days are required to determine if the species is present. We rec- The dryas monkey was formerly thought to be a local- ommend utilizing local knowledge and using this species-spe- ized relict species, known only from a single population cific camera-trap method in other areas of the central Congo in the Luo Scientific Reserve, Iyondji Community Bonobo basin to determine the wider distribution of the dryas monkey. Reserve, Kokolopori Bonobo Reserve and forest near Djombolanda Village in Tshuapa Province, Democratic Keywords Camera trap, canopy research, Cercopithecus Republic of the Congo (Fig. ; Kuroda et al., ; dryas, Chlorocebus, Democratic Republic of the Congo, Lokasola, ; Sakamaki et al., ; A. Lokasola, pers. disturbance, dryas monkey, Lomami National Park comm., ). This small range justified the categorization Supplementary material for this article is available at of the species as Critically Endangered (Hart et al., ). doi.org/./S However, new information about the dryas monkey’s range was reported in , when field assistants from the TL Project (named after the landscape between the rivers Tshuapa, Lomami and Lualaba) documented two dryas Introduction monkeys killed by hunters in Bafundo Forest, Maniema Province, km south-east of the species’ known range lthough Ernst Schwarz described the dryas monkey (Hart, ). This range expansion justified a recategoriza- ACercopithecus dryas in , it remains one of tion of the dryas monkey as Endangered, and emphasized ’ Africa s most enigmatic primates. Poor documentation of the need for field studies (Hart et al., ). A limiting factor for investigating the distribution of the DANIEL ALEMPIJEVIC ( orcid.org/0000-0002-0468-4679) and KATE M. DETWILER dryas monkey is that it is difficult to detect. The TL Project (Corresponding author, orcid.org/0000-0003-4597-133X) Florida Atlantic did not detect the dryas monkey during the first years of University, 777 Glades Rd, Boca Raton, 33431, USA. E-mail [email protected] biodiversity surveys, despite documenting other primate JOHN A. HART ( orcid.org/0000-0002-5800-0156) and TERESE B. HART – – species (Hart et al., ). Dryas monkeys are primarily Frankfurt Zoological Society, Tshuapa Lomami Lualaba Project, Kinshasa, Democratic Republic of the Congo reported in secondary forest thickets (Kuroda et al., ; Received January . Revision requested March . Lokasola, ). Kuroda et al. ( ) encountered dryas mon- Accepted June . keys in the understorey and feeding on the ground, but
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, Downloadeddistribution, from https://www.cambridge.org/core and reproduction in any medium,. IP address: provided 170.106.40.139 the original work, on is 02 properly Oct 2021 cited. at 00:20:15, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/termsOryx, Page 1 of 8 © The Author(s),. https://doi.org/10.1017/S0030605320000575 2021. Published by Cambridge University Press on behalf of Fauna & Flora International doi:10.1017/S0030605320000575 2 D. Alempijevic et al.
FIG. 2 Illustration of an adult male dryas monkey Chlorocebus dryas, drawn from photographs of an individual killed by a hunter in the Bafundo Forest, for use in educational material distributed in local communities, to help bio-monitoring patrol teams inform people of the protected status of the inoko, and to solicit information on the occurrence of the species. FIG. 1 The global distribution of the dryas monkey Chlorocebus dryas, endemic to the Democratic Republic of the Congo, – indicating the location of the Luo Djombolanda population two sites in Lomami National Park and its buffer zone in (Luo Scientific Reserve, Iyondji Community Bonobo Reserve, Maniema Province, Democratic Republic of the Congo. Kokolopori Bonobo Reserve, Djombolanda Forest) and the Lomami National Park and buffer zone population. Specific Lomami National Park encompasses , km of lowland locations where dryas monkeys have been observed in Lomami rainforest and savannah bisected by the Lomami River. National Park and its buffer zone are labeled. The Park was established in and with its buffer zone covers c. , km in the TL Landscape. The landscape , surveys using camera traps placed at ground level in Iyondji has villages, the residents of which practice shifting ’ Community Bonobo Reserve and Lomami National Park and agriculture, fishing and hunting in the Park s buffer zone. its buffer zone failed to detect them (Sakamaki et al., ; We selected Bafundo Forest in the buffer zone for J.A. Hart et al., unpubl. data). Although camera traps are camera-trap surveillance, starting at the location where the widely used to detect and survey cryptic species, it is neces- first reported dryas monkey was killed by a hunter. This for- – sary to develop specific camera-trap placements that could est was the site of Bafundo Village during , before reliably detect dryas monkeys. its residents moved to their current location km to the Local knowledge has been shown to provide useful infor- south-west. We established the second survey site km mation on understudied and cryptic species (Cano & Tellería, west of Bafundo Village, at Camp Bartho in Lomami ;Nguyenetal.,). We therefore solicited information National Park after a ranger patrol team saw a dryas monkey on the dryas monkey from residents of villages in the Lomami there in . Camp Bartho was occupied by one family – National Park’s buffer zone to determine the distribution of during and included five dwellings and several the dryas monkeys and select sites for camera-trap surveil- gardens. Since then, the family moved their camp to the lance. We then used camera traps to document stratum west bank of the Lomami River, outside the Park. and habitat preference and estimate the relative abundance of the dryas monkey at two sites, one each in Lomami National Park and its buffer zone. Specifically, we tested the Methods following hypotheses: dryas monkeys () prefer the under- – storey mid canopy strata, ( ) prefer disturbed patches over Distribution mature forest, and () would be detected more frequently in Lomami National Park than in its buffer zone, where hunt- We created a dryas monkey illustration matching the pelage ing is more common. We also developed a species-specific of the adult male specimen killed in Bafundo Forest (Fig. ). camera-trap method to detect the species. We used it to create a poster that invited people to come for- ward with information about sightings of the species, locally known as inoko. We conducted informal interviews oppor- Study area tunistically when an informant volunteered information. We distributed the poster in villages and incorporated it This study involved two field surveys: Phase I (October into the species identification material used by patrol –July ) and Phase II (August –March )at teams. We trained the teams in species identification and
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FIG. 3 The spatial relationship between sampling points in the strategic and systematic surveys, and the distribution of dryas monkey detections at the Camp Bartho and Bafundo Forest survey sites.
equipped them with cameras to take photographs of any (Fig. ). The mean distance of each camera-trap placement dryas monkeys seen during patrols. If a patrol team encoun- to the pre-determined sampling point was . m ± SD . m. tered a dryas monkey or if one killed by a hunter was photographed, we considered these as confirmed occur- Video processing and analysis rences (Hart, ). We grouped videos into an event if # minutes passed between dryas monkey videos from the same camera trap. We grouped trap-days per stratum to compare trap effort Camera-trap survey design between strata. Trap-days are the total number of days a We developed a multi-strata camera-trap technique with a camera trap was functional in the field. If a camera trap was placement of three camera traps at each survey point, one not functioning when we retrieved it, we considered the date each monitoring the ground, understorey and canopy. We and time of the last video recorded as the last trap-day. positioned the camera traps on game paths (.–. m We calculated the dryas monkey detection rate per above ground), shrubs and liana tangles (.–. m), and stratum (dryas monkey events/camera-trap days × )to horizontal limbs (.–. m) forming pathways to adja- compare events across surveys with different trap effort. cent tree crowns (Gregory et al., ). We used the single- To determine if dryas monkeys show preference for a rope technique to access the canopy, and the double-rope particular stratum, we compared detections per stratum – technique to move to the desired camera-trap location between sites and surveys using the Kruskal Wallis rank when needed (Maher, ). sum test. To calculate the minimum trap effort required We used Bushnell (Overland Park, USA) camera traps to detect a dryas monkey from our data, we determined (models Trophy Cam , Trophy Cam , Trophy the probability distribution of time between events by fitting Cam Aggressor , Essential E ). We pro- the observed detection rates to a Poisson point process for grammed them to take -second high-quality videos over each survey (Supplementary Fig. ). a -hour period using high sensitivity and a -second rest period. Habitat modeling PhaseIwasastrategicsurveytoincreaseourchances of detecting dryas monkeys, using camera-trap place- To create a predictive model of dryas monkey habitat pref- ments in Bafundo Forest and Camp Bartho (Fig. ). We erence, we considered six a priori covariates. As both local set placements in locations where informants had seen knowledge and previous studies indicated dryas monkeys dryas monkeys, or in areas with a dense understorey, prefer disturbed sites (Kuroda et al., ; Lokasola, ), where informants had indicated dryas monkeys prefer to we recorded covariates related to forest structure in a forage. We set two additional camera traps in the under- -m diameter plot at all sampling points in Phase II. storey at the edge of a recently abandoned garden at We recorded per cent canopy cover, canopy height, and Camp Bartho. understorey complexity (the number of times vegetation Phase II was a systematic survey, to eliminate bias in touched a -m vertical pole; modified from Suarez-Rubio detection rates, in Bafundo Forest and Camp Bartho. We se- et al., )at and m height in the cardinal directions lected sampling points mapartin. km -grid cells from the sampling point, recorded the number of trees and
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TABLE 1 Data on the occurrence of the dryas monkey Chlorocebus TABLE 2 Frequency of detection of dryas monkeys in the forest dryas collected opportunistically during patrols in Lomami National understorey (.– m) and the estimated minimum trap effort re- Park and its buffer zone, Democratic Republic of the Congo (Fig. ). quired for a % probability of detecting the species, using camera traps in the Phase I and Phase II surveys (see text for details and Location Verification Year Fig. ) in Bafundo Forest and Camp Bartho. Lifale Patrol observation; photograph 2019 Kakongo Patrol observation 2018 Detection Minimum 1 2 Luanga Hunter kill; photograph 2018 Survey Survey design frequency trap effort Djekoshilo Patrol observation 2018 Bafundo Forest I Strategic 1.67 179.28 Biseke Patrol observation 2018 Bafundo Forest II Systematic 2.22 135.02 Camp Bartho Patrol observation; camera trap 2014 Camp Bartho I Strategic 0.82 364.45 Bafundo Forest Hunter kill; camera trap 2014 Camp Bartho II Systematic 0.28 330.953
Number of events per trap days. Trap effort (camera-trap days) required to be % certain a dryas monkey will be detected if present at a site. their diameter at breast height (DBH; . cm), and noted Actual trap effort accumulated before detecting a dryas monkey in the the presence or absence of fallow fields. We examined survey. any potential differences in habitat characteristics between Bafundo Forest and Camp Bartho using a multivariate analysis of variance. We used logistic regression to model the presence/ab- sence of dryas monkeys at camera-trap sampling points as a function of habitat covariates. We did not record DBH, number of trees, or understorey complexity during Phase I, and therefore we used the mean values from Phase II for these variables. To avoid problems associated with collinearity between covariates, we used variable inflation factors calculated with the ISLR . package in R .. (R Core Team, ). Covariates with a variable inflation factor . were excluded from the model. We deter- mined the covariate(s) that had the most predictive power from the global model, from which we selected the covariate(s) with the lowest Akaike’s information cri- terion (AIC) score and P # ..Weanalysedvariation between the null and residual deviance using analysis of variance. To evaluate candidate models, we calculated AIC corrected for small sample size (AICc) and maximum likeli- hood values using the MuMin .. package, to determine the fit of the global model and select the most parsimonious FIG. 4 The height above ground at which dryas monkeys were detected by camera traps in strategic (I) and systematic (II) model. We examined the relative importance of each vari- surveys in the Bafundo Forest and Camp Bartho. The boxes able using the per-variable sum of model weights. We deter- represent the median height with upper and lower quartiles mined variable importance based on the predictive power of where dryas monkeys were detected (% greater and % lesser each variable in the model, and then calculated the prob- than the median); whiskers represent maximum/minimum ability of detecting dryas monkeys for the important values, and circles outliers. variables.
’ Results Fig. ). The dryas monkey s range (its extent of occur- rence) in Lomami National Park and its buffer zone is We confirmed seven occurrences of dryas monkeys in , km (Fig. ). Lomami National Park and its buffer zone during – Camera traps detected dryas monkeys at both sites and based on opportunistic reports provided by local in both surveys (Plate ). Detection frequencies were high- residents and park patrols (Table ). Observations were er in Bafundo Forest than in Camp Bartho. The minimum confirmed in the edge of gallery forest, at sites of current number of days of accumulated trap effort required for a or historical anthropogenic activity, and in an area of nat- % certainty of detecting dryas monkeys was – ural liana abundance in mature forest (Supplementary (Table ).
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TABLE 3 Comparison of six habitat characteristics of Bafundo Forest and Camp Bartho, with the mean and standard deviation of each covariate per site, and the F and P values from the multivariate analysis of variance.
Characteristic Bafundo Forest Camp Bartho F P Mean ± SD diameter at breast height (. 10 cm) 27.04 ± 10.91 25.07 ± 4.11 0.21 Mean ± SD tree density (. 10 cm) 9.75 ± 4.73 20.58 ± 4.38 32.12 ** Mean ± SD % canopy cover 38.20 ± 16.25 46.45 ± 11.89 1.75 Mean ± SD canopy height (m) 18.35 ± 8.47 18.12 ± 5.51 0.13 Mean ± SD understorey complexity1 49.67 ± 17.57 31.00 ± 10.36 11.75 * Mean ± SD fallow fields (presence/absence) 0.83 ± 0.39 0.25 ± 0.45 14.41 *
*P , .; **P , .. Number of times vegetation touched a vertical pole m in height.
Camera traps accumulated , trap-days on the ground, , trap-days in the understorey and , trap-days in the canopy. Understorey camera traps recorded dryas mon- key events, canopy camera traps detected a single event, and dryas monkeys were not detected by camera traps at ground level. We found no significant difference in detection height across surveys (P = .; Fig. ). Some aspects of forest structure differed significantly between Bafundo Forest and Camp Bartho (Table ). There were more fallow fields and the forest understorey was more complex in Bafundo Forest (Plates & ), and tree density was significantly higher in Camp Bartho. All six covariates had variance inflation factors , , and therefore we used all covariates in the logistic model. In the global model, fallow fields was the only covariate iden- PLATE 1 Still-frame from a camera-trap video of an adult male tified as a significant predictor of dryas monkey presence dryas monkey Chlorocebus dryas in Bafundo Forest in the buffer zone of Lomami National Park (Fig. ). (Table ). Importance tests of the covariates in the best- fit models (Table ; see Supplementary Material for all models) indicate fallow fields was the covariate of greatest assumptions that the species occurs further to the west in importance ( . ). The likelihood of detecting dryas monkeys Salonga National Park (Thys van den Audenaerde, ). on the edge of fallow fields was higher ( . ) than in mature Kingdon’s() suggestion that dryas monkeys could forest ( . ). occur at more westerly localities south of the Congo River needs to be investigated with further surveys. Our camera-trap placements detected dryas monkeys Discussion almost exclusively in the understorey across all surveys, regardless of canopy structure, supporting our hypothesis Our study of the dryas monkey population in Lomami that the species prefers the understorey–mid canopy strata. National Park and its buffer zone adds to our knowledge A few monkeys were recorded descending out of view to- of the distribution, stratum preference, and habitat use of wards the ground. Dryas monkeys have been seen foraging this enigmatic species. Most of the new records of the spe- on Aframomum and Megaphrynium (Kuroda et al., ; cies came from the knowledge of local people. People that Kingdon, ), both abundant herbs in fallow fields in directly depend on forest resources are often knowledgeable the Bafundo Forest (Plate ). However, as the camera traps about local biodiversity (Gadgil et al., ). Even rapid, on the ground did not detect dryas monkeys, it seems un- unstructured interviews can be useful, but reports need to likely they travel on the ground. Only one camera trap in be confirmed, as we did, with camera traps or other comple- the canopy detected a dryas monkey, suggesting they rarely mentary methods (Nguyen et al., ). travel in the upper canopy. The known distribution of dryas monkeys includes both Dryas monkeys showed a preference for the edges of fal- banks of the Lomami River, a major tributary of the Congo low fields, supporting our hypothesis that the species prefers River (Fig. ). Therefore, the Congo River may be the only disturbed patches over mature forest. Dryas monkeys were fluvial barrier to the species’ distribution. No population detected most frequently in Bafundo Forest during the has been confirmed west of the Tshuapa River, despite Phase II survey, where we encountered the greatest area of
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PLATE 2 Understorey structure typical of fallow fields in Bafundo Forest (left) and mature forest at Camp Bartho (right) in the buffer zone and Lomami National Park, respectively.
TABLE 5 Habitat logistic regression models for habitat use by dryas monkeys in Camp Bartho and Bafundo Forest.
Model AICc1 ΔAICc2 AICcWt3 Fallow fields 52.23 2.86 0.03 Canopy height + fallow fields + tree 50.51 1.14 0.08 density + understorey complexity
AICc, Akaike’s information criterion adjusted for small sample size. ΔAICc, difference in Akaike’s information criterion adjusted for small sample size in relation to the top model. AICcWt, relative likelihood of the model adjusted for small sample size.
strepsirhines, Arctocebus calabarensis and Euoticus elegan- tulus, are restricted to liana-rich microhabitats (Charles- Dominique, ). In Ituri Forest (.°N,.°E), PLATE 3 View from the canopy of a fallow field in Bafundo Cercopithecus ascanius specializes in foraging for arthropods Forest, characterized by sparse trees, dense herbs, and lianas. in forest gaps (Thomas, ). In Lomami National Park and its buffer zone dryas monkeys use mature forest, but prefer disturbed forest patches.
TABLE 4 The six covariates tested for inclusion in multivariate logis- Despite being hunted in the buffer zone, dryas monkeys tic models of habitat use by dryas monkeys at two sites in Lomami were mostly detected in Bafundo Forest, and thus our National Park and its buffer zone, selected based on literature and hypothesis that the species would be detected more in local ecological knowledge, with the mean and standard deviation Lomami National Park than in its buffer zone was not sup- ̅± (x SD) and probability of each covariate in the model. We collected ported by our data. It was not possible from our data to covariate data strategically from disturbed forest where local hunters separate the effects of hunting and fallow fields, but the suggested dryas monkeys were likely to be encountered (n = )and systematically sampled every m at the same sites (n = ). gains received by exploiting disturbed sites must presum- ably outweigh the cost of being hunted. We are not aware Covariate x̅± SD P of any reports of dryas monkeys in local or regional bush- Diameter at breast height (. 10 cm) 0.03 ± 0.07 meat markets, and thus the species may be harvested at Tree density (. 10 cm) 0.31 ± 0.18 a lower rate than other monkey species. Local people in ± % canopy cover 0.04 0.03 Bafundo Village indicated the monkey is too small − ± Canopy height (m) 0.22 0.13 to send to market and the species’ preference for dense Understorey complexity 0.14 ± 0.07 thicket makes them difficult to shoot. Fallow fields (presence/absence) 5.01 ± 1.95 * Although hunting and habitat loss are causing global *P , .. declines in primate populations (Estrada et al., ), African primates have adapted to forest edge conditions in the past during dry climatic periods (De Almeida-Rocha anthropogenic disturbance. The small (.–. kg) body size et al., ). Dryas monkeys may be exploiting disturbed of dryas monkeys may be adapted to living in such dense patches in the Congo Basin, as Chlorocebus does along the vegetation (Kuroda et al., ). Basin’s periphery. The sightings in Djekoshilo and Luanga Some primates prefer disturbed microhabitats in other- at the southern limit of the rainforest block are within wise mature forest (Bourlière, ). Two West African km of the northern range limit of Malbrouck’s monkey
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Chlorocebus cynosuros (Sarmiento, ). The dryas mon- References key’s use of gallery forest, and the southern extent of its range, should be explored further to determine possible BOURLIÈRE, F.Ç. ( ) Primate communities: their structure and role in tropical ecosystems. International Journal of Primatology, , . sympatry between dryas and Malbrouck’s monkeys. CANO, L.S. & TELLERÍA, J.L. () Local ecological knowledge as a We were able to detect the dryas monkey with our place- tool for assessing the status of threatened vertebrates: a case study ments of three camera traps arranged vertically in different in Vietnam. Oryx, , –. forest strata, and at least trap-days are required to CHARLES-DOMINIQUE,P.() Ecology and Behaviour of Nocturnal achieve a % detection probability, although dryas mon- Primates: Prosimians of Equatorial West Africa. Gerald Duckworth keys may be detected sooner in suitable habitat. The cam- & Co Ltd, London, UK. COLYN, M., GAUTIER-HION,A.&THYS VAN DEN AUDENAERDE, eras that detected the species most frequently were those D.F.E. () Cercopithecus dryas Schwarz and C. salongo Thys in the lower strata of the canopy and understorey, at – van den Audenaerde are the same species with an age-related m above ground. Because foliage was dense and branches coat pattern. Folia Primatologica, , –. thin at – m above ground, this stratum was not suitable DANDELOT,P.() Order primates. In The Mammals of Africa, an for placement of camera traps, although we observed dryas Identification Manual (eds J. Meester & H.W. Setzer), p. . Smithsonian Institute Press, Washington, DC, USA. monkeys at this height (Supplementary Fig. ). DE ALMEIDA-ROCHA, J.M., PERES, C.A. & OLIVEIRA, L.C. () Our findings indicate that Lomami National Park and its Primate responses to anthropogenic habitat disturbance: a buffer zone contain the greatest extent of the species’ known pantropical meta-analysis. Biological Conservation, , –. range (Fig. ), and Lomami is the only National Park with ESTRADA, A., GARBER, P.A., RYLANDS, A.B., ROOS, C., a confirmed population. High heterozygosity and low in- FERNANDEZ-DUQUE, E., DIFIORE, A. et al. ( ) Impending extinction crisis of the world’s primates: why primates matter. breeding measures from genomic analysis of a hunter-killed Science Advances, ,e. dryas monkey (collected on October ) from Bafundo GADGIL, M., BERKES,F.&FOLKE,C.() Indigenous knowledge Forest suggest that it was a representative of a larger contigu- for biodiversity conservation. Ambio, , –. ous population (van der Valk et al., ). We recommend GILBERT, C., GILISSEN, E., ARENSON, J., PATEL, B., NAKATSUKASA, that researchers and conservationists working in the central M., HART, T. et al. (in press) Morphological analysis of new dryas monkey specimens from the central Congo Basin: taxonomic basin of the Democratic Republic of the Congo mobilize considerations and an emended diagnosis. American Journal of local knowledge to identify other areas where the dryas Physical Anthropology. monkey occurs and confirm any reports using our camera GREGORY, T., CARRASCO RUEDA, F., DEICHMANN, J., KOLOWSKI,J.& trap placement technique. ALONSO,A.() Arboreal camera trapping: taking a proven method to new heights. Methods in Ecology and Evolution, , –. Acknowledgements We dedicate this manuscript to Pablo Ayali GROVES,C.() Why taxonomic stability is a bad idea, or why are (1981–2018) for his commitment to the dryas monkey project and there so few species of primates (or are there?). Evolutionary the conservation of Lomami National Park. This research was Anthropology, , –. funded by the Lukuru Foundation, Margot Marsh Biodiversity GUSCHANSKI, K., KRAUSE, J., SAWYER, S., VALENTE, L.M., BAILEY, S., Foundation (001378), Mohammed Bin Zayed Species Conservation FINSTERMEIER, K. et al. () Next-generation museomics Fund (162513850), Florida Atlantic University, Primate Conservation disentangles one of the largest primate radiations. Systematic Incorporated (1322), International Primatological Society, Dynamic Biology, , –. Youth Community, and crowd funding. We thank Erik Noonburg HART, T.B. () Inoko and the camera trap thief. Searching for and Michael Lawes for statistical support and helpful comments; Bonobo in Congo. bonoboincongo.com////inoko-and- Jeanne Pierre Kapale, Henri Silegowa, Aimedo Onale, Boniface thecamera-trap-thief [accessed November ]. Kamanya, Chief Onombe Djecko and other informants who reported HART, T.B. () Dryas monkey: Critically Endangered? Not dryas monkey observations; Marten Balimu, Reddi Bosisa and John anymore. Searching for Bonobo in Congo. bonoboincongo.com/ I. Mponga for assistance with camera trapping; and Martin Fisher, ///critically-endangered-not-anymore [accessed Jef Dupain and an anonymous reviewer for their suggestions. November ]. HART, J.A., BUTYNSKI, T.M. & HURLEY,M.() Cercopithecus Author contributions Study design: DA, KD, JH, TH; fieldwork: dryas.InThe IUCN Red List of Threatened Species : DA; data analysis: DA; writing : DA, KD, JH, TH. e.TA. dx.doi.org/./IUCN.UK..RLTS. TA.en [accessed November ]. Conflicts of interest None. HART, J.A., DETWILER, K.M., ALEMPIJEVIC, D., LOKASOLA,A.& RYLANDS, A.B. () Cercopithecus dryas.InThe IUCN Red List of Ethical standards This non-invasive research used no-flash camera Threatened Species : e.TA. dx.doi.org/./ traps. L’Institut Congolais pour la Conservation de la Nature granted IUCN.UK.-.RLTS.TA.en [accessed November research permission to work in Lomami National Park. The local chiefs ]. of Bafundo, Likandjo and Bote villages and the sector chief of Maniema HART, J.A., DETWILER, K.M., GILBERT, C.C., BURRELL, A.S., FULLER, Province granted permission to access the forest. Florida Atlantic J.L., EMETSHU, M. et al. () Lesula: a new species of Cercopithecus University’s Institutional Review Board (916126-4) and the Institutional monkey endemic to the Democratic Republic of Congo and Animal Care and Use Committee (A16-27) approved our research implications for conservation of Congo’s central basin. protocol. PLOS ONE, ,e.
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