Archived 2011-2012 topics: Yellow-casqued Hornbill (Ceratogymna elata) and Brown-cheeked Hornbill (Bycanistes cylindricus): request for information

Initial deadline for comments: 31 January 2012 [note that this has been moved back by about two months].

BirdLife species factsheets for Yellow-casqued Hornbill and Brown-cheeked Hornbill

Yellow-casqued Hornbill Ceratogymna elata and Brown-cheeked Hornbill Bycanistes cylindricus inhabit forested areas in West Africa. C. elata occurs disjunctly from Senegal to Cameroon, while B. cylindricus has a more restricted distribution, occurring from Guinea to Togo. Both species prefer primary forest but may also occur in logged or secondary forest, as well as plantations (Thiollay 1985; Fry et al. 1988; Holbech 1992, 1996; Gartshore et al. 1995).

Both of these species are currently listed as Near Threatened under criteria A2c,d; A3c,d; A4c,d on the basis that they are undergoing moderately rapid declines (typically 20-29% over 10 years or three generations) owing to habitat loss, fragmentation and degradation and the impacts of hunting pressure.

BirdLife estimates the generation length for B. cylindricus at c.19 years, thus the trend should now be estimated over a three-generation period of 57 years. The generation length for C. elata is now estimated by BirdLife to be c.15.8 years, thus this species’s population trend should now be estimated over a period of 47 years.

Recent observations suggest that both species are in rapid decline in Ghana. Hunting pressure has led to the extirpation of both species from Bia National Park (NP), where there have been no records of either since 1991 (Dowsett-Lemaire and Dowsett 2011a), although both of them persist at a number of other sites, including small numbers of B. cylindricus at Atewa Range Forest Reserve (FR) and Tano Ofin FR, despite high hunting pressure at these locations (Dowsett-Lemaire and Dowsett 2009b). Surveys of Atewa Range FR over 16 days in June 2006 yielded records of B. cylindricus on only three occasions, including only one pair, perhaps owing to movements in search of food, but contrasting with more frequent observations in February 2005 (McCullough et al. 2007), possibly indicating depleted numbers.

Several hunters interviewed by Dowsett-Lemaire and Dowsett (2009b) in Ghana have said that B. cylindricus has become rare or difficult to find and, according to the forest guard at Fure Headwaters, the species might be extinct there. B. cylindricus may also have disappeared from Opro River FR (Dowsett-Lemaire and Dowsett 2010).

C. elata still occurs in eastern Ghana, albeit in very small numbers (Dowsett-Lemaire and Dowsett 2009b), which may not represent a viable population (Dowsett-Lemaire and Dowsett 2009a), but has been found to be common at Ankasa Resource Reserve (RR) (Dowsett-Lemaire and Dowsett 2010). C. elata has not been recorded at Atewa Range FR since 2005 at least, with perhaps the last confirmed record in May 2002 (per Dowsett-Lemaire and Dowsett 2011b).

Data and observations are requested from other parts of these species’ ranges to confirm whether the situation in Ghana is representative of their overall status. It is noted, however, that any assessment of population trends in these species must account for their movements in search of food resources. If evidence suggests that either species has undergone or is projected to experience a decline of at least 30% over three generations, they may be eligible for uplisting to Vulnerable. A rate of decline estimated to be at least 50% over three generations would qualify them for uplisting to Endangered.

References:

Dowsett-Lemaire, F. and Dowsett, R. J. (2009a) Comments on forest reserves visited in eastern Ghana in 2009: wildlife (with special reference to birds) and conservation status. A report prepared for the Forestry Commission, Accra, Ghana. Dowsett-Lemaire Misc. Report 63.

Dowsett-Lemaire, F. and Dowsett, R. J. (2009b) Comments on selected forest reserves in SW Ghana: wildlife and conservation status. A report prepared for the Forestry Commission, Accra, Ghana. Dowsett-Lemaire Misc. Report 64.

Dowsett-Lemaire, F. and Dowsett, R. J. (2010) Comments on selected forest reserves visited in SW Ghana in 2009-2010: wildlife (especially birds) and conservation status. A report prepared for the Forestry Commission, Accra. Dowsett-Lemaire Misc. Report 67.

Dowsett-Lemaire, F. and Dowsett, R. J. (2011a) Ornithological surveys in Bia National Park and Resource Reserve, Ghana (January 2005, December 2009 and September 2010). A report prepared for the Wildlife Division, Forestry Commission, Accra. Dowsett-Lemaire Misc. Report 73.

Dowsett-Lemaire, F. and Dowsett, R. J. (2011b) An update on the birds of Atewa Range Forest Reserve, Ghana. A report prepared for the Wildlife Division, Forestry Commission, Accra. Dowsett-Lemaire Misc. Report 74.

Fry, C. H., Keith, S. and Urban, E. K. (1988) The birds of Africa vol III. London: Academic Press.

Gartshore, M. E., Taylor, P. D. and Francis, I. S. (1995) Forest birds in Côte d’Ivoire. Cambridge, U.K.: BirdLife International (Study Report 58).

Holbech, L. H. (1992) Effects of selective logging on a rain-forest bird community in western Ghana. University of Ghana, and University of Copenhagen (Thesis. MSc).

Holbech, L. H. (1996) Faunistic diversity and game production contra human activities in the Ghana high forest zone, with reference to the Western Region. Copenhagen:Zoological Institute/Museum, University of Copenhagen.

McCullough, J., Alonso, L. E., Naskrecki, P., Wright, H. E. and Osei-Owusu, Y. (Eds) (2007) A Rapid Biological Assessment of the Atewa Range Forest Reserve, Eastern Ghana. RAP Bulletin of Biological Assessment 47. Arlington, VA: Conservation International.

Thiollay, J.-M. (1985) The birds of Ivory Coast: status and distribution. Malimbus 7: 1-59.

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  3. Archived 2011-2012 topics: Knobbed Hornbill (Aceros cassidix) and Sulawesi Hornbill (Penelopides exarhatus): uplist to Near Threatened?
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10 Responses to Archived 2011-2012 topics: Yellow-casqued Hornbill (Ceratogymna elata) and Brown-cheeked Hornbill (Bycanistes cylindricus): request for information

  1. Hugo Rainey says:

    1. Generation length: although there are probably limited numbers of observations for estimation of the generation length for these two species, as C. elata is 50-100% heavier than B. cylindricus, it is unlikely that its generation length is shorter than that of B. cylindricus given that they are similar taxonomically. However, given that the generation time is relatively high for both species, this is not a major issue.

    2. Rainey & Zuberbuhler (2007) demonstrated that C. elata, C. atrata and B. cylindricus made seasonal movements from the evergreen Tai forest in Ivory Coast and were present in low numbers there from March-June. These movements are probably related to fruit abundance. Thus, comments on observations of hornbill abundance in West African forests need to take into account this phenomenon: observations between Feb 2005 and June 2006 in the Atewa Range in Ghana are not strictly comparable.

    3. Although hornbills can travel many kilometres in a single day in search of ephemeral fruiting trees, the increasing fragmentation of the Upper Guinea forest is likely to have affected their populations, particularly as fragmentation is ongoing and large fragments become increasingly isolated. For example, C. atrata has not been seen in Marahoué NP since the observations noted in Thiollay (1985) (Christy & Schulenberg 1999, HJR pers. obs.). Thus, in general, hornbills may have been extirpated from some more isolated forest fragments.

    4. As noted in Rainey & Zuberbuhler (2007), the hornbills that apparently migrate from Tai NP are likely to move to the semi-deciduous forests of sites such as Mont Péko and Mont Sangbé NPs to the north. Here large forest fragments are still quite well connected to the north as well as to the west into Liberia and Guinea. However, deforestation is ongoing and both the Forets Classées of Cavally (Ivory Coast) and Mont Béro (Guinea) have apparently been cleared. If hornbill generation length is really 15-19 years, then their populations are likely to be threatened at quite high levels over three generations as there is deforestation and other development pressures, particularly in Liberia, are ongoing even in the best remaining areas.

    5. An assessment of forest cover over Upper Guinea would help provide an indication of change in hornbill population size, particularly if this assessment demonstrated that either evergreen or semi-evergreen forests had been particularly badly affected, thus removing an essential part of the range of these migratory species.

    6. During a survey of three Ghanaian Forest Reserves (Draw River, Bio-Tano and Krokosua) from October-November 2003, we observed a large hornbill only once in good habitat (Rainey & Asamoah 2005). This should normally have been during the period when hornbills were present at these sites. Previous surveys had indicated their presence there which suggests that fragmentation and hunting have probably reduced their numbers.

    7. Surveys in Haute Dodo and Cavally in Ivory Coast had good populations of hornbills in 2001, but these may have subsequently declined (Demey & Rainey 2005) if for example, Cavally has been cleared.

    References
    Christy, P. & Schulenberg, T., 1999. L’avifaune du parc national de la Marahoué, Cote d’Ivoire, pp 53-65. In: Schulenberg, T.S., Short, C.A. & Stephenson, P.J. (eds.) A biological assessment of Parc National de la Marahoué, Cote d’Ivoire. RAP Working Papers 13, Conservation International, Washington, DC.

    Demey, R. & Rainey, H.J. 2005. A Rapid Survey of the Birds of the Haute Dodo and Cavally Classified Forests, pp 76-90, 162-167. In: Alonso, L.E., Lauginie, F. & Rondeau, G. (eds.). A Rapid Biological Assessment of two Classified Forests in South-Western Côte d’Ivoire. RAP Bulletin of Biological Assessment 34. Conservation International. Washington, D.C.

    Rainey, H. J. & Zuberbühler, K. 2007. Seasonal variation in hornbill abundance in a West African national park detected using analysis of acoustic recordings. Bird Conservation International 17: 235-244.

    Rainey, H.J. & Asamoah, A. 2005. Rapid assessment of the birds of Draw River, Boi-Tano and Krokosua Hills, pp 50-56, 142-149. In: McCullough, J., Decher, J. & Guba Kpelle, D. (eds.). A biological assessment of the terrestrial ecosystems of the Draw River, Boi-Tano, Tano Nimiri and Krokosua Hills forest reserves, southwestern Ghana. RAP Bulletin of Biological Assessment 36. Conservation International, Washington, DC.

  2. Hugo Rainey says:

    During surveys across Upper Guinea from 1999-2003 with colleagues I observed large hornbills at a number of sites. Abundance indices obtained were as follows:

    Abundance indices:
    C – Common: encountered daily, either singly or in significant numbers
    F – Fairly common: encountered on most days
    U – Uncommon: irregularly encountered and not on the majority of days
    R – Rare: rarely encountered, one or two records of single individuals

    Mont Péko National Park, Ivory Coast,1999-2001 (Rainey 2000, Rainey 2001, Francis, Taylor & Miner pers. comm. (their report should be with BirdLife))
    Ceratogymna elata: C
    Ceratogymna atrata: U
    Bycanistes cylindricus: C
    Bycanistes subcylindricus: C

    Haute Dodo Foret Classee, Ivory Coast, March-April 2001 (Demey & Rainey 2005)
    Ceratogymna elata: U
    Ceratogymna atrata: absent
    Bycanistes cylindricus: U
    Bycanistes subcylindricus: U

    Cavally Foret Classee, Ivory Coast, March-April 2001 (Demey & Rainey 2005)
    Ceratogymna elata: C
    Ceratogymna atrata: C
    Bycanistes cylindricus: C
    Bycanistes subcylindricus: R

    Pic de Fon, Guinea, November -December 2002 (Demey & Rainey, 2004a, 2004b)
    Ceratogymna elata: F
    Ceratogymna atrata: absent
    Bycanistes cylindricus: absent
    Bycanistes subcylindricus: absent

    Déré Foret Classee, Guinea, Nov-Dec 2003, (Demey & Rainey 2006)
    Ceratogymna elata: C
    Ceratogymna atrata: absent
    Bycanistes cylindricus: absent
    Bycanistes subcylindricus: C

    Diécké Foret Classee, Guinea, Nov-Dec 2003, (Demey & Rainey 2006)
    Ceratogymna elata: C
    Ceratogymna atrata: absent
    Bycanistes cylindricus: C
    Bycanistes subcylindricus: R

    Mont Béro Foret Classee, Guinea, Nov-Dec 2003, (Demey & Rainey 2006)
    Ceratogymna elata: U
    Ceratogymna atrata: absent
    Bycanistes cylindricus: absent
    Bycanistes subcylindricus: F

    Francis, Taylor & Miner (pers. comm.) observed three of the large hornbills (not C. atrata) in a number of semi-deciduous forest reserves in mid-western Ivory Coast in 2001. Their report should be with BirdLife.

    References
    Demey, R. & Rainey, H.J. 2006. Rapid surveys of the birds of the Fôret Classées de Déré, de Diécké and du Mont Béro, Southeastern Guinea, pp 59-68, 159-167, 236-244. In: Wright, H.E., McCullough, J., Alonso, L.E. & Diallo, M.S. (eds.). 2006. A Rapid Biological Assessment of Three Classified Forests in Southeastern Guinea. RAP Bulletin of Biological Assessment 40. Conservation International, Washington, DC.

    Demey, R. & Rainey, H.J. 2005. A Rapid Survey of the Birds of the Haute Dodo and Cavally Classified Forests, pp 76-90, 162-167. In: Alonso, L.E., Lauginie, F. & Rondeau, G. (eds.). A Rapid Biological Assessment of two Classified Forests in South-Western Côte d’Ivoire. RAP Bulletin of Biological Assessment 34. Conservation International. Washington, D.C.

    Demey, R. & Rainey, H.J. 2004a. The birds of Pic de Fon Forest Reserve, Guinea: a preliminary survey. Bulletin of the African Bird Club 11: 126-138.

    Demey, R. & Rainey, H.J. 2004b. A rapid survey of the birds of the Forêt Classée du Pic de Fon, Guinea, pp 61-66, 165-171, 238-247. McCullough, J. (ed.). A Rapid Biological Assessment of the Forêt Classée du Pic de Fon, Simandou Range, Southeastern Republic of Guinea. RAP Bulletin of Biological Assessment 35. Conservation International, Washington, DC.

    Rainey, H.J. & Asamoah, A. 2005. Rapid assessment of the birds of Draw River, Boi-Tano and Krokosua Hills, pp 50-56, 142-149. In: McCullough, J., Decher, J. & Guba Kpelle, D. (eds.). A biological assessment of the terrestrial ecosystems of the Draw River, Boi-Tano, Tano Nimiri and Krokosua Hills forest reserves, southwestern Ghana. RAP Bulletin of Biological Assessment 36. Conservation International, Washington, DC.

    Rainey, H.J. 2001. Bird survey and staff training in the Parc National du Mont Péko 22 February – 25 March 2001. Unpublished report to BirdLife International.

    Rainey, H.J. 2000. The avifauna of the Parc National du Mont Péko, Côte d’Ivoire. Unpublished report to BirdLife International.

  3. Philip Hall says:

    Yellow-casqued Hornbills are uncommon in Okomu National Park in the SW of Nigeria and in other protected areas and do not appear under threat. Previously they used to be common throughout the Niger Delta but recent disturbances there have made it impossible to verify what the current situation is.

  4. Hugo Rainey says:

    A correction to my post above on the status of hornbills at Haute Dodo Foret Classee:

    Haute Dodo Foret Classee, Ivory Coast, March-April 2001 (Demey & Rainey 2005)
    Ceratogymna elata: U
    Ceratogymna atrata: U
    Bycanistes cylindricus: U
    Bycanistes subcylindricus: absent

  5. Hugo Rainey says:

    Correction to my first post, point 4 – it is Déré Foret Classée that has mostly been cleared, not Mont Béro Foret Classée.
    Additionally, inspection of forest cover in Google Earth seems to indicate that Cavally Fore Classée is fortunately still relatively intact.

  6. Yellow-casqued Hornbill is widespread and common in Gola Forest, Sierra Leone (Klop et al 2010), amongst the commonest of the species of global conservation concern found in the area. Surveys in 2006-2007 (Klop et al 2008) found it in all parts of the forest with birds recorded from 56% of 627 point counts which equated to an average encounter rate of 2.6 per hour. A survey in 2007 found it to be very common, recorded several times daily usually in pairs or small family groups (Dowsett-Lemaire and Dowsett2007).

    A more recent rapid survey of the border areas between Gola Forest and Liberia and the Gola National Forest in Liberia in 2011 (Demey 2011) also found it to be commonly encountered, the commonest of the large hornbills, with daily encounter rates of 2 to 8 individuals.

    It is not obviously under threat from hunters as the forest is relatively well protected as Gola Rainforest National Park. But the skulls of the large hornbill species are of interest for cultural purposes (Klop et al 2008). Plenty of large trees remain in Gola Rainforest National Park so suitable nest site are assumed to be avialable.

    The species is commonly seen on Tiwai Island, adjacent to Gola, where groups of 5 to 10 birds can be seen.

    This species is not confined to continuous forest nor the protected area in eastern Sierra Leone. It is still regularly encountered in community lands surrounding Gola Forest and can sometimes be seen in the relatively well-farmed countryside nearer the main eastern town of Kenema, and it persists in the Kambui Hills Forest Reserve, adjacent to Kenema.

    Demey, R. 2011. Ornithological survey of the transboundary area Sierra Leone / Liberia of Gola Forest. Report to The RSPB for Across the River
    – A Transboundary Peace Park for Sierra Leone and Liberia (ARTP).

    Dowsett-Lemaire, F. and Dowsett, R.J.D. (2007). Faunistic survey of Gola Forest (Sierra Leone) in January-February 2007, with an emphasis on birds. Report to The RSPB, Sandy.

    Klop, E., Lindsell, J.A. and Siaka, A. (2008). Biodiversity of Gola Forest, Sierra Leone, RSPB and CSSL research report.

    Klop, E., Lindsell, J.A. and Siaka, A. (2010). The birds of Gola Forest and Tiwai Island, Sierra Leone. Malimbus 32: 33-58.

  7. Brown-cheeked Hornbill is present in Gola Forset, Sierra Leone in far lower numbers than Yellow-casqued – recorded from 8% of point counts – though this may partly reflect reduced detectability. It is frequently encountered at edges, but not usually far from intact forest so is not often recorded in the wider countryside as Yellow-casqued is. So it seems far less able to cope with habitat conversion. Distribution in the forest seems to be more patchy than some other species but I suspect this may reflect more nomadic behaviour as birds follow fruiting trees. Numbers are usually twos and threes and there never seem to be the large aggregations that can be experienced for bycanistes species in eastern Africa.

  8. Joe Taylor says:

    The following information and comments were sent by Françoise Dowsett-Lemaire on 27 January 2012:

    2. Brown-cheeked Hornbill Bycanistes cylindricus

    GHANA
    Brown-cheeked Hornbill Bycanistes cylindricus
    Distribution Guineo-Congolian endemic (Upper Guinea endemic, from Sierra Leone to SW Ghana; a single record from central Togo is best considered unconfirmed). Confined to the forest zone of the south-west, where its range is shrinking. There are no records, not even from the past, from the transition zone including east of the Volta. The map makes the distinction between areas where likely extinct (hollow squares) and others with recent records (in the 2000s): survives in Ankasa N.P. (uncommon, Dowsett-L. & Dowsett 2011x), Subri River F.R. (very local, B. Phalan in 2007), Kakum N.P. (south and north, fairly common, many observers), Boin River F.R. (seen in protection block in 2003) and in the same square recorded also in Tano Ehuro in 1988 (Dutson & Branscombe 1990, a forest reserve largely destroyed by farming, Hawthorne & Abu-Juam 1995), and in Tano Nimri F.R. in 1994 (Holbech 2005 and unpub.), Sui River F.R. (rare, experienced hunters interviewed in Dec 2008), Pra Anum F.R. (several pairs, p.o. Nov 2009), Atewa Range F.R. (common in 2005, but much decreased since, with one record in Apr 2010, D-L. & D. 2011x), and in the same square in Nsuensa F.R. (common, B. Phalan in 2007), Krokosua Hills F.R. (considered rare in 2003, H. Rainey), and Tano Ofin F.R. (a few on plateau, Jan 2009). Possibly still present in Dome River F.R. (in south of 06°01°CW) where P. Beier recorded it in 2000. Has apparently or probably disappeared from the following areas (hollow squares): Draw River F.R. (very rare, one record in 32 days by L. Holbech in 1995), Bonsa Ben F.R. (hunters’ report), Fure Headwaters F.R. (forest guard), Suhuma F.R. (status uncertain, the forest is still big), considered extinct in Bia N.P. since the early 1990s (Dowsett-L. & Dowsett 2011x), extinct in Opro River F.R. (recorded in 2000 by P. Beier, but none in 2010 and much forest replaced by teak plantations); has disappeared also from Amama Shelterbelt F.R. (seen in Jan 2005 by A. Hester, but forest since destroyed for gardens and plantations, p.o. 2010), although status in adjacent Bosumkese F.R. unknown (recorded in 2005-6 by A. Hester). Although not mentioned by Grimes (1987) there is also an old record from Mampong by J.M. Winterbottom (in Bannerman 1933), in an area now almost totally deforested.
    Ecology and habits Little known in Ghana; male of a pair at Atewa seen eating seeds of an epiphytic orchid.
    Status Resident, with probably some wandering.
    Conservation Threatened by both deforestation (see above) and hunting. In theory protected in Ankasa and Kakum N.Ps, and probably Krokosua Hills (now under the Wildlife Division); its demise from Bia N.P. is probably related to the logging of the southern section in the 1990s, together with uncontrolled hunting.
    Breeding Male taking food to nest hole, 20 Jan (M. Horwood in Grimes 1987, no locality). Size of male gonads (cf. Lowe 1937, repeated by Grimes 1987) considered as being of limited significance.
    Taxonomy No races recognized.
    References Bannerman (1933); Dowsett-Lemaire & Dowsett (2011x: Ankasa, Atewa); Grimes 1987); Hawthorne & Abu-Juam (1995); Holbech (2005).

    TOGO
    Even though Cheke & Walsh (1996. Birds of Togo) published one record for central Togo, we are sceptical about this. Some of their records were obtained when flying over rivers in a helicopter, and the habitat for this locality is dominated by savanna woodland and riparian forest (not typical of the rain forests inhabited by this hornbill). We feel that B. fistulator was more likely in that sort of situation. Thus it would appear that SW Ghana is the eastern limit of range, until proven otherwise.

    SIERRA LEONE
    In our report on Gola Forest (2007, sent to BirdLife), we wrote: “Widespread, in small numbers. Recorded on 22 out of 32 days in the field, throughout but mainly at edges of clearings and in secondary forest. Less common in primary forest (most of our sightings/hearings in primary forest in Gola North were from the Konella clearing)”.

    Conclusion: the status of this species is getting worrying, and it should best be “upgraded” to Vulnerable, if not Endangered. Near Threatened (on a par with much more widespread passerines that are not hunted, like Copper-tailed Starling) is not suitable. In Liberia there are recent plans for turning vast areas of primary rain forest into oil palm plantations (details known to your office), which will seriously hit this species. Decrease of range in Ghana in last few decades is very obvious. Moreover, all forest reserves are threatened with disappearance within next 20 years, as demand for wood far exceeds the offer of legal timber. Thus illegal chainsaw logging finds a ready market, even for government buildings. There is also a lot of illegal farming, extensive in some areas (e.g. Tano Ofin, and further north in other reserves where the hornbill has probably existed in the past, but we have no records.)

  9. Joe Taylor says:

    The following information and comments were sent by Françoise Dowsett-Lemaire on 27 January 2012:

    Yellow-casqued Hornbill Ceratogymna elata

    GHANA
    Yellow-casqued Hornbill Ceratogymna elata
    Distribution Guineo-Congolian endemic (Upper Guinea near-endemic, from Sierra Leone to W. Cameroon). Mainly in the forest zone of the south-west, where its range is decreasing, with still a very few records from the transition zone east of the Volta. The map makes the distinction between areas where the species is considered extinct (hollow squares) and others where it seems to survive (with most records in the 2000s). Thus in the south-west there are recent reports from Cape Three Points (2004-5, p.o. & B. Phalan in 2007), Ankasa N.P. (common), Draw River F.R. (Holbech 2005) and Subri River F.R. (Holbech 2005, B. Phalan in 2006, experienced hunter in 2008) east to Kakum N.P. (frequent, both south and north, many observers), and from Boin River F.R. (protection block in 2003) east to Esen Epam F.R. (records based on reports by forest guards and experienced hunters who were able to distinguish between this and Black-casqued Hornbill); north of 6°N still occurs in Sui River F.R. (experienced hunters, 2008); has become very rare in Atewa Range with last records from 2002 (A. Riley) and possibly 2005 (southern end). Still common in the Ongwam forest in Bomfobiri W.R. (Dowsett-L. & Dowsett 2011b), and noted in Bosumkese F.R. in 2005-6 (A. Hester). Considered extinct (hollow squares) near Takoradi (Dabocrom in Bannerman 1933), probably Suhuma F.R. (or else very few left), and certainly in Bia N.P. (since the early 1990s, Dowsett-L. & Dowsett 2011x); known from Owabi W.R. (near Kumasi) in the past (wildlife guards). There are historical records also from Goaso and Ejura (Lowe 1937), and it is long gone too from the riparian forests of Kete Kratchi (undated record by R.E. Crabbe in Grimes 1987), at least since they disappeared into Lake Volta in the 1960s. East of the Volta has become very rare but still reported from Togo Plateau F.R. in 2009, one seen between Biakpa and Amedzofe and heard once at Afadjato (both Apr 2008).
    Ecology and habits Little known in Ghana; a specimen shot by Lowe (1937) had eaten a Myristicaceae fruit, and several were eating fruits of Pycnanthus angolensis (of the same tree family) in Jan 2005 in the Ongwam forest of Bomfobiri W.R. (Dowsett-Lemaire & D. 2011b).
    Status Resident, with at least local wandering.
    Conservation Threatened by both deforestation and hunting, see above. Expected to disappear very soon from the small forests east of the Volta; its survival in the larger forest patch of Assoukoko on the Togo side is also in doubt (p.o. Mar 2011). Protected in the wildlife reserves of Ankasa, Kakum and Bomfobiri; its demise from Bia N.P. is probably related to the logging of the southern section in the 1990s, together with uncontrolled hunting.
    Breeding Feeding at nest in two separate nest holes in Terminalia superba, 14 and 16 Jan 1953; a fully fledged young on 30 Apr 1954 (all from M. Horwood in Grimes 1987).
    Taxonomy No races recognized.
    References Bannerman (1933); Dowsett-Lemaire & Dowsett 2011b (Bomfobiri); Dowsett-Lemaire & Dowsett 2011x (Bia)

    TOGO
    A recent survey in March and May 2011 has failed to locate this species in what is left of forest in the west of the country. See a report sent to BirdLife in 2011 (to L. Fishpool and library, I think). In particular, it is probably extinct now from the Assoukoko forest (south and north of 8°00′N near the Ghana border), which is the largest forest left today in Togo. Last recorded by R. Cheke from the Koue river in 1988, to the north of Assoukoko (in Cheke & Walsh 1996).

    SIERRA LEONE
    Gola forest. Our report (2007, when we visited) says: “Very common, recorded several times daily. Usually in pairs or small family groups. Seen feeding on figs (Ficus lutea, F. macrosperma) and fruit of palms (Raphia, Laccosperma) and small fleshy fruits of various lianes (Apocynaceae etc.).”
    Gola has become a national park.

    LIBERIA
    Recent surveys in the Nimba range have located this species in both East Nimba Nature Reserve and West Nimba Community Reserve. You should ask B. Phalan for all coordinates (he is presently completing our joint report). The text reads: “Two heard inside East Nimba reserve in primary forest (east of Grassfield) on 9 Nov 2011 (F. Dowsett-Lemaire), between 550-600 m. Also recorded in south-west corner of reserve and near Geipa by R. Demey (in 2008-9: singles, a pair and once three together), while B. Phalan saw one then four east of Grassfield airstrip on 8 Apr 2010. West Nimba Community Reserve: one male calling (and coming to tape) at 07.50°N, 08.69°W on 1 Nov (FD-L) is our only record in 9 days.

    (numbers are evidently very small today in this section of Liberia).

    CAMEROON
    In the mountains of W. Cameroon, this species tends to be less common than C. atrata. Thus in the Bakossi Mts, we have only one record of elata: a group of three seen by I. Faucher near Ekeb (in 1998) (whereas atrata is widespread in lowland forest up to at least 1100 m).

    Yabassi Hills, report (2001) sent in electronic copy last Dec. (via L. Fishpool).
    In foothills of Nlonako Mt and the Yabassi Hills however, at the limit of its range, C. elata was still locally common in 1999-2001: “Fairly common in the Nlonako Forest on the Nkébé and Nkam rivers (foothills, see map in report). Several pairs seen and roosting on hills above Ndokiti (with C. atrata) and seen as far east as the Makombé river (at 10°26′E). Like its congener, attracted to an invasion of caterpillars in Lophira (Ndokiti).” (Position of Makombé forest shown on map).
    We understand that the Makombé forest may be logged selectively; I am not sure of the present conservation status of Nlonako.

    Conclusion. The status of this species in West Africa is worrying. In Ghana in particular, is about to disappear from Volta Region (and also from adjacent Togo) and all forest reserves in south-west are doomed by logging and farming. The reserves will probably disappear within the next 20 years. Thus, outside some national parks this species has no future. Should be upgraded to “Vulnerable” or “Endangered”, much like B. cylindricus. Its numbers remain a bit higher (probably) and its range is also bigger, reaching Cameroon.

  10. Joe Taylor says:

    The following comments were sent by Françoise Dowsett-Lemaire on 27 January 2012:

    When using reports by hunters/forest guards, we have had to be especially cautious with Byc. cylindricus, because we suspect that some hunters could not distinguish between B. cylindricus and B. fistulator. On the other hand, they knew the big Ceratogymna better, and often distinguished between C. elata (pale bill) and C. atrata (dark bill). Several people interviewed mentioned that only C. elata was still present; this fits in with our own field observations that C. atrata has a much smaller range than C. elata today, and there are no records (even in the past) of atrata from the transition zone or east of the Volta. In fact, Cer. atrata and also Byc. subcylindricus are in an even worse situation in West Africa than their congeners.

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