Low Abundance of the Endangered Timneh Parrot Psittacus Timneh in One of Its Presumed Strongholds

Low abundance of the Endangered timneh parrot Psittacus timneh in one of its presumed strongholds

S IMON V ALLE,NIGEL J. COLLAR,BENJAMIN B ARCA P ATRICK D AUDA and S TUART J. MARSDEN

Abstract Although both the grey parrot Psittacus erithacus most of its range (Clemmons, ; Martin et al., ), and the recently recognized timneh parrot Psittacus timneh but a handful of stronghold areas, such as the Bijagós are categorized as Endangered because of harvest for the pet Archipelago in Guinea-Bissau (Lopes et al., a,b) and trade and loss of habitat, the latter has a much smaller range Sapo National Park in Liberia (Freeman et al., ), may and may be largely restricted to a few stronghold areas. In retain fairly healthy populations of the species (Dändliker, March–April  we surveyed for a total of  hours in ; Clemmons, ; Lopes et al., b). Recent surveys and around one of these presumed strongholds, the large in Côte d’Ivoire, however, have indicated dramatic declines and well-protected Gola Rainforest National Park, the across the country, including in the most important forest Sierra Leonean portion of the Gola Transboundary Peace protected area, Taï National Park (Marsden et al., ; Park. Timneh parrots were encountered at a rate of . Martin et al., ). groups/h in the National Park and . in the buffer zone, in- The Gola Rainforest National Park is the Sierra Leonean   dicating densities of – individuals per km . These figures portion of the , km Gola Transboundary Peace Park are similar to recent density estimates from the Liberian side shared with Liberia. Since the s the National Park has of the Peace Park, suggesting that the transboundary popu- been managed by the national government in partnership lation amounts to c. , individuals inside the Park and an with the UK Royal Society for the Protection of Birds, and unknown number in the surrounding areas. Densities of the in  became West Africa’s first verified REDD+ project timneh parrot may be generally low even in strongholds, its (Barca et al., b). As such, it constitutes one of the largest numbers may be declining steeply, and the global popula- and best-managed remnants of the Upper Guinean forest in tion size is probably lower than previously believed. West Africa. Because of the Park’s size and management, and because it lies at the heart of the range of P. timneh,it Keywords Conservation, encounter rate, Gola Rainforest was believed to host a significant proportion of the species’ National Park, grey parrot, Psittacus timneh, Sierra Leone, global population (BirdLife International, b). West Africa, wildlife trade Gola Rainforest National Park (Fig. ) is dominated by lowland moist evergreen high forest, with an annual rainfall   he timneh parrot Psittacus timneh, formerly considered of c. , mm, mostly falling in a single wet season from  conspecific with the grey parrot Psittacus erithacus,is May to October (Lindsell et al., ). The Park currently T   endemic to five countries in the western Upper Guinea consists of two main forest blocks (Gola South, c. km ,   forests of Africa: from Guinea-Bissau and Guinea through and Gola Central, c. km ) and a smaller sector (Gola    Sierra Leone and Liberia to western Côte d’Ivoire (del North, c. km ), surrounded by a -km buffer zone   Hoyo & Collar, ). Trapping for the caged bird trade, (c. km ). Formal agreements with most of the local combined with high rates of forest loss, has caused a chiefdoms in the buffer zone support small-scale agri- major decline of the species across its range (Martin et al., culture, agroforestry and other local livelihood activities ). Although both Psittacus species have recently aimed at reducing intensive exploitation of the forest. been recategorized as Endangered on the IUCN Red List However, illegal gold and diamond prospecting, plus po- (BirdLife International, b), P. timneh has the smaller tential concessions to oil palm companies, are an ongoing  range and population. It has probably disappeared from threat (BirdLife International, a). From  March to  April , SV spent  hours across  days surveying for P. timneh in and around Gola SIMON VALLE (Corresponding author, orcid.org/0000-0001-9402-1360) Rainforest National Park, including the two main blocks, School of Natural Sciences, Bangor University, Bangor, Gwynedd, LL57 2UW, with . hours (across  days) inside the Park and . UK. E-mail [email protected] hours (across  days) in the buffer zone. Walking surveys NIGEL J. COLLAR BirdLife International, Cambridge, UK occupied %( hours) of this time and observations BENJAMIN BARCA and PATRICK DAUDA Royal Society for the Protection of Birds/ from fixed points %( hours). Only one site, Gola Gola Rainforest National Park, Kenema, Sierra Leone South, was surveyed twice from the Sileti guest house, for STUART J. MARSDEN School of Science & the Environment, Manchester  Metropolitan University, Manchester, UK minutes each time. As dense vegetation prevented safe access and because of time constraints, surveys were con- Received  March . Revision requested  May . Accepted  June . First published online  October . ducted only along forest trails (% of survey hours) or

Oryx, 2020, 54(1), 74–76 © 2019 Fauna & Flora International doi:10.1017/S0030605319000802 Downloaded from https://www.cambridge.org/core. IP address: 170.106.34.90, on 28 Sep 2021 at 03:50:58, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0030605319000802 Endangered timneh parrot 75

FIG. 1 Gola Rainforest National Park with its -km buffer zone and the locations of the transects surveyed for the timneh parrot Psittacus timneh.

transects cut for a previous study of primates (% of survey TABLE 1 Summary of encounters of the parrot Psittacus timneh hours). Surveys were at all hours of the day from morning to within Gola Rainforest National Park and its buffer zone during dusk (but were suspended during rain or strong winds), March‒April . and all P. timneh heard and seen were counted. Encounter Survey Survey No. of No. of rates (groups/h) were subsequently computed for both the hours days encounters individuals National Park and its buffer zone, and from these numbers Gola Rainforest National Park density was inferred using the calibration in Marsden et al. Gola Central 29.6 5 3 6 (). A number of factors (e.g. detectability, observer skill, Gola South 41.3 7 5 10 seasonal variation in group size, local variability in bird mo- Buffer zone bility) may affect the precision of estimates calculated with Lalehun 15.0 7 1 2 this method, resulting in progressively larger confidence Nyayema 5.6 1 1 2 intervals at higher densities. Community Forest Nomo Faama 22.6 5 10 18 During surveys P. timneh was encountered  times (on   Chiefdom of days; eight times in Gola Rainforest National Park, Total 114.1 25 20 38  times in the buffer zone), with a total of  individuals recorded ( in the National Park,  in the buffer zone); the Nomo Faama Chiefdom, in the buffer zone, accounted considered a probable stronghold of the species and has for most encounters and individuals (Table ). Parrots were benefited from long-term, effective conservation manage- only recorded in small groups (mean . ± SD .). Overall en- ment, as manifest by its extensive well-preserved forest counter rate was . groups/h (. in the National Park, . and healthy populations of frugivore species such as the in the buffer zone), which approximates to  individual per Vulnerable yellow-casqued hornbill Ceratogymna elata   km (%CI–) in the National Park, and  per km (% (Valle et al., ) and Endangered Upper Guinea red colo- CI –) in the buffer zone. bus Piliocolobus badius (Barca et al., a). We do not This study, although brief, is the most extensive survey know whether P. timneh has always had a low density in of P. timneh conducted in and around Gola Rainforest the National Park or has suffered recent declines, but the National Park. We found densities much lower than those sparse evidence points to the latter. Anecdotal reports of of reasonably healthy populations of the congeneric grey large numbers of birds formerly roosting in the Nomo parrot (Marsden et al., ), although they were similar Faama Chiefdom (PD, pers. obs.) and of previous heavy  to the . individuals per km found in the Liberian trapping suggest that harvest for the pet trade may have portion of the Transboundary Peace Park where, however, played a major role in reducing the area’s population. We aflockof birds was seen on one occasion (Marsden found no indication that parrots are currently trapped et al., , ). The Gola Rainforest National Park is there for the pet trade. Surveys in  yielded similarly

low encounter rates (Dowsett-Lemaire & Dowsett, ) BARCA, B., TURAY, B.S., KANNEH, B.A., & TAYLEUR,C.(b) Nest and in  P. timneh was recorded at only one locality out- ecology and conservation of Western Chimpanzees (Pan troglodytes verus) in Gola Rainforest National Park, Sierra Leone. Primate side the National Park, on the border with Liberia (Demey,  –  Conservation, , . ). The highest number of encounters was recorded in BIRDLIFE INTERNATIONAL (a) Important Bird Areas Factsheet: the Nomo Faama Chiefdom; this could be because exploi- Gola Forests. Http://www.birdlife.org [accessed  February ]. tation there is more focused on gold mining than on agricul- BIRDLIFE INTERNATIONAL (b) Species Factsheet: Psittacus ture (i.e. disturbance and forest clearing are less extensive). timneh. Http://datazone.birdlife.org/species/factsheet/   There were a similar number of records in the National Park [accessed February ]. CLEMMONS,J.() Status Survey of the African Grey Parrot and its buffer zone, suggesting that a matrix of habitats may (Psittacus erithacus timneh) and Development of a Management be beneficial for the species (Valle et al., ), although Program in Guinea and Guinea-Bissau. CITES Secretariat, Geneva, we do not yet know how the species uses each area (e.g. Switzerland. for feeding, roosting or nesting). DÄNDLIKER,G.() Le Perroquet Gris (Psittacus erithacus)en Guinée. Evaluation des Populations, Contribution à la Biologie, Given the large area of protected forest within Gola ’    Étude de l Exploitation Commerciale et Recommandations pour la Transboundary Peace Park ( , km ) and its buffer Gestion. Report sur le Projet CITES S-. Unpublished report. CITES zones, even low-density estimates (mean density . parrots  Secretariat, Geneva, Switzerland. per km ) indicate a reasonable population size. We suggest DEL HOYO,J.&COLLAR, N.J. () Illustrated Checklist of the Birds of that the population within the Peace Park itself may be the World. Lynx Edicions, Barcelona, Spain.  c. , individuals, with a currently unknown but perhaps DEMEY,R.( ) Ornithological Survey of the Transboundary Area Sierra Leone/Liberia of Gola Forest:  February– March . substantial number in the buffer zones around the Park. Unpublished report. However, the true population size could be smaller DOWSETT-LEMAIRE,F.&DOWSETT,R.() Faunistic Survey of because of the imprecision associated with our method. Gola Forest (Sierra Leone) in January–February , with an There is strong evidence that the species has disappeared Emphasis on Birds. Unpublished Report. RSPB, Sandy, UK. from the majority of its range (Martin et al., ), and FREEMAN, B., DAMI, F.D. & MOLOKWU-ODOZI,M.() Status of the future for wild P. timneh rests largely in Gola, along globally threatened birds of Sapo National Park, Liberia. Ostrich, , –. with the Bijagós Islands, Guinea-Bissau (where there are LINDSELL, J.A., KLOP,E.&SIAKA, A.M. () The impact of civil war c. , individuals: Lopes et al., a,b) and Sapo on forest wildlife in West Africa: mammals in Gola Forest, Sierra National Park, Liberia (c. , individuals: Freeman Leone. Oryx, , –. et al., ). Although it now seems likely that the global LOPES, D.C., MARTIN, R.O., HENRIQUES, M., MONTEIRO, H.,  population is lower than the estimated . , (BirdLife CARDOSO, P., TCHANTCHALAM, Q. et al. ( a) Combining local  knowledge and field surveys to determine status and threats to International, b), further research on the species in timneh parrots Psittacus timneh in Guinea-Bissau. Bird Liberia and Sierra Leone, within and outside protected Conservation International, published online  October . areas, including measures to boost productivity if further LOPES, D.C., MARTIN, R.O., HENRIQUES, M., MONTEIRO, H., evidence emerges of recent trapping, is a priority. REGALLA, A., TCHANTCHALAM, Q. et al. (b) Nest-site characteristics and aspects of the breeding biology of the Acknowledgements We thank Eric Vignot and the Parrot Wildlife Endangered timneh parrot Psittacus timneh in Guinea-Bissau. Foundation for generously funding this research, Mohamed Nyallay Ostrich, , –. for assistance in the field, Brima Sheku Turay and Pietro Sandini for MARSDEN, S.J., LOQUEH, E., TAKUO, J.M., HART, J.A., ABANI, R., support with logistics, Gola Rainforest National Park for permission AHON, D.B. et al. () A protocol to allow density estimation to carry out research, and two anonymous reviewers for their valuable and monitoring of the heavily traded grey parrots across comments. their huge African ranges. In Strengthening Capacity for Monitoring and Regulation of International Trade of African Grey Parrot (ed. CITES), pp. –. CITES Secretariat, Geneva, Author contributions Study design and fieldwork: SV, SM; data Switzerland. analysis: SV, SM; writing: SV, NC, BB, SM. MARSDEN, S.J., LOQUEH, E., TAKUO, J.M., HART, J.A., ABANI, R., AHON, D.B. et al. () Using encounter rates as surrogates for Conflicts of interest None. density estimates makes monitoring of heavily-traded grey parrots achievable across Africa. Oryx, , –. Ethical standards This research abided by the Oryx guidelines on MARTIN, R.O., PERRIN, M.R., BOYES, R.S., ABEBE, Y.D., ANNORBAH, ethical standards. N.D., ASAMOAH, A. et al. () Research and conservation of the larger parrots of Africa and Madagascar: a review of knowledge gaps and opportunities. Ostrich, , –. References VALLE, S., COLLAR, N.J., HARRIS, W.E. & MARSDEN, S.J. () Spatial and seasonal variation in abundance within an insular grey parrot  – BARCA, B., TAYLEUR, C., & TURAY, B.S. (a) Recovery of Upper population. African Journal of Ecology, , . Guinea Red Colobus Piliocolobus badius and Other Primates in Gola VALLE, S., COLLAR,N.&MARSDEN,S.() Abundance and Rainforest National Park, Eastern Sierra Leone. Presented at the th Distribution of Timneh Parrot Psittacus timneh in and Around Gola International Primatological Society Congress – August . Rainforest National Park, Sierra Leone. Unpublished report. Parrot Nairobi, Kenya. WildLife Foundation, Crécy-la-Chapelle, France.