M. Di Vittorio 1*, F. Petrozzi 2

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1 Vie et milieu - Life and environment, 2018, 68 (1): Preliminary data on the birds of prey at Mole National Park (Ghana), including the first record of Gyps fulvus and a short synopsis of the literature on this species occurrence in West Africa M. Di Vittorio 1*, F. Petrozzi 2 1 Ecologia Applicata Italia srl, Via Jevolella 2, Termini Imerese (PA), Italy 2 Via Jenner 70, Rome, Italy Corresponding author: divittoriomassimiliano@gmail.com BIRDS OF PREY EURASIAN GRIFFON VULTURE GHANA SYNOPSIS OF WEST AFRICAN DATA ABSTRACT. During field surveys conducted in the year 2011 in the Mole National Park (Northern Region, Ghana), several species of bird of prey were observed, and their abundance was roughly estimated. Among the species observed in the park, there were two individuals of European Griffon Vulture (Gyps fulvus) that were observed in May Our records are the first observations for this vulture species in Ghana, and probably the southernmost records for this species. These records could indicate a further evidence of the dispersion into sub-saharan Africa from Europe as a range expansion trend for the species in West Africa. Introduction The Eurasian Griffon vulture (Gyps fulvus) is considered an uncommon Palaearctic migrant and a scarce winter visitor in Central and Western Africa (Barlow et al. 1997). However, outside the European range, records of this species were reported in different areas of sub- Saharan Africa (Salvan , Dupuy 1976, Browne 1982, Alonso 1984, Gee 1984, Shull et al. 1986, Newby et al. 1987, Nikolaus 1987, Carroll 1988, Giraudoux et al. 1988, Sauvage & Rodwell 1988, Rodwell et al. 1996, Barlow et al. 1997, Layna 1997, Dowsett et al. 1999, SI/ SIC 2000, Clark 2001, Crisler et al. 2003, Camiña 2004, Barlow 2005, Languy 2006, Perco 2006, Roy 2006, Strandberg et al. 2007). Moreover, in the last years the wintering population of this species is increasing in some parts of West Africa (Gutiérrez 2003, Godino & Machado 2015). In general, the total European population size of this vulture increased in the last years (BirdLife International 2017), especially in Spain (breeding population increased by 506 % between 1979 and 1999, Martí & Del Moral 2003). Probably because of this population growth, during autumn migration more than 5000 Eurasian Griffons migrates from Europe to Africa across the Gibraltar Strait (Camiña 2004). Furthermore, as showed for other species of birds (Berthold et al. 2004), another factor that could affect the movement of this vulture to Sub Saharan Africa, is climate change. In fact these changes were considered to be the most important threat regarding the distribution range variation of many species of birds, in terms of shifting (DEFRA 2005), reduction (Malcolm et al. 2006) and/or increasing (Bradbury et al. 2011). Although climate change could play an important role, the expansion of the Eurasian Griffon vulture may depend more on its population increasing, and even niche interactions with other species of vultures, and more generally, of birds of prey, could not be a priori excluded. Therefore, basic research on the distribution and ecology of birds of prey is urgently needed in West Africa, and especially in the protected areas of the savannah vegetation zone. The present note aims at fulfilling three aims: (i) reporting a preliminary list of the species of birds of prey recorded by us during some surveys conducted at the Mole National Park (Ghana), (ii) reporting for the first time the occurrence of some Eurasian Griffon vultures in Ghana, and (iii) summarize and discuss the records of occurrence for this species in the various West African countries. Materials and Methods The study area is the Mole National Park (approximately N, W), Northern Region, Ghana (Fig. 1), that is the largest and oldest of Ghana s protected areas and covers approximately 4600 km 2. In Mole National park, open savannah areas with sparse vegetation or bushlands represent the main environmental type (Fig. 2). In fact, open woodland savannah with grass under growth and open grassland are the most typical cover of the park (Dankwa-Wiredu & Euler 2002, Burton et al. 2011). During the wet season, the presence of water in the park is wide, due to a complicated network of rivers flowing into the White Volta. During May 2011, a survey was conducted in the Mole National Park. Telescopes (10 60) and binoculars (8 42) were used for the observations.

2 20 M. DI VITTORIO, F. PETROZZI Fig. 1. Mole National Park land cover. Fig. 2. Main habitat types of Mole National Park (Ghana). The survey was done by two observers walking along random transects for a total of about 120 hours (60 hours per observer), and by using an observation point, where observations were done early in the morning (2 hours per day) and at the sunset (2 hours per day), for a total of 80 hours. Both transects and the observation point were located in the southern part of the Park, thus all original records presented in this paper were carried out in the southern part of Mole National Park. For each species, an index of apparent abundance was defined: very rare = records 5 % of total observations; rare = records 10 % of total observations; common = records 40 % of total observations; very common = records > 40 % of total observations. In order to compare our data with the IUCN status, we joined the apparent abundance, due to the observations in the park, with the IUCN red list categories. In our surveys when the species were rare or very rare, we considered these abundance categories correspondent to the IUCN status NT (Near Threat- ened), VU (Vulnerable), EN (Endangered), and CR (Critically Endangered). Results and Discussion 23 species of birds of prey were recorded during the present survey (see Table I for the check list of species and their apparent abundance). Four species were very rare, 11 were rare, 5 were common, and 3 were very common. Except for Griffon vulture (which has an increasing population in Europe, while in Africa, because of the few records, can be defined uncommon), and for other 2 species that are data deficient, for 9 of the observed species in the study area, the abundances reflect quite well the general abundance in the African regions (BirdLife International 2017). For the remaining 11 species the abundances differ between the Park and the IUCN status. These spe-

3 MOLE NATIONAL PARK BIRDS OF PREY 21 Table I. Species of birds of prey recorded at Mole national Park in the year 2011, including their apparent index of abundance, their global status and population trend in Africa. * Gyps fulvus population in Europe is increasing, while in Africa there are few records, hence in this continent it can be defined as uncommon Common name Scientific name Apparent abundance in Mole NP IUCN Red List (2018) Population trend Martial Eagle Polemaetus bellicosus Rare Vulnerable Decreasing Tawny Eagle Aquila rapax Rare Least Concern Decreasing Wahlberg s Eagle Hieraaetus wahlbergi Very rare Least Concern Stable Grasshopper Buzzard Butastur rufipennis Rare Least concern Decreasing Red-necked Buzzard Buteo auguralis Common Least Concern Increasing Pale Harrier Circus macrourus Rare Near Threatened Decreasing Brown Snake Eagle Circaetus cinereus Rare Least Concern Decreasing Abyssinian Lanner Falco biarmicus abyssinicus Rare Data deficient Data deficient Hobby Falco subbuteo Rare Least Concern Decreasing Palm-nut Vulture Gypohierax angolensis Common Least Concern Stable White-backed Vulture Gyps africanus Common Critically Endangered Decreasing Eurasian Griffon vulture* Gyps fulvus Very rare Least Concern Increasing Rueppell s Griffon Gyps rueppelli Very rare Critically Endangered Decreasing African Hawk Eagle Aquila spilogaster Common Least Concern Decreasing Yellow-billed kite Milvus aegyptius parasitus Very common Data deficient Data deficient Hooded Vulture Necrosyrtes monachus Very common Critically Endangered Decreasing African Harrier-hawk Polyboroides typus Rare Least Concern Stable Cassin s Hawk-eagle Spizaetus africanus Rare Least Concern Decreasing Bateleur Terathopius ecaudatus Very common Near Threatened Decreasing White-headed Vulture Trigonoceps occipitalis Rare Critically Endangered Decreasing African Fish-eagle Haliaeetus vocifer Common Least Concern Stable Secretary Bird Sagittarius serpentarius Very rare Vulnerable Decreasing Lizard Buzzard Kaupifalco monogrammicus Rare Least Concern Stable Fig. 3. Pictures of some observed species: 1) African Hawk Eagle 2) Eurasian Griffon vulture 3) White-headed Vulture 4) Bateleur 5) Martial Eagle 6) African Harrier-hawk 7) Hooded Vulture 8) White-backed Vulture 9) Lizard Buzzard. cies are Tawny Eagle, Wahlberg s Eagle, Grasshopper Buzzard, Brown Snake Eagle, Hobby, African Harrierhawk, Cassin s Hawk-eagle and Lizard Buzzard, rare in our surveys and that are quite common and widespread in Africa, while White-backed Vulture, Hooded Vulture and

4 22 M. DI VITTORIO, F. PETROZZI Bateleur, generally rare (BirdLife International 2017), were in the Mole Park a commonly observed species. It should be noted that 14 of the observed species have a decreasing population trend, while 5 are stable and only 2 are increasing; 4 of the species (Table I) are evaluated as Critically Endangered in IUCN Red List category, 2 as Vulnerable, 2 as Near Threatened and 13 as Least Concern (BirdLife International 2017). In four occasions, in the southern part of Mole National Park, one adult and one immature of Eurasian Griffon vulture (Fig. 3) were observed. These vultures were always flying jointly with some White-backed vulture (Gyps africanus) and Hooded Vulture (Necrosyrtes monachus) individuals. We recognized these two vultures as Gyps fulvus because they showed: i) a paler face; ii) a cream colored bill; iii) a plumage uniformly brown and clearer than the African Griffons, without the white underwing coverts and the white rump patch (immediately diagnostic for Gyps africanus); iv) a size much bigger than the other vultures that were flying nearby them. Other species of vultures observed in the Park were: White-backed Vulture (Gyps africanus), Rüppell s Griffon Vulture (Gyps rueppelli), Hooded Vulture (Necrosyrtes monachus) and White-headed Vulture (Trigonoceps occipitalis) (Table I). The Eurasian Griffon vultures were always observed flying over areas of open savannah woodland. This is the first observation of Griffon vulture in Ghana, and probably one of the southernmost for this species. We interpret these findings as an evidence of apparent dispersion of this species into sub-saharan Africa from Europe. Indeed, it is well known that this species may be involved into long-distance movements, especially the juveniles and immature individuals (Bernis 1983, Griesinger 1996, Griesinger 1998, Gavashelishvili 2005, McGrady & Gavashelishvili 2006). Thus, it is hypothesized that the Ghanaian population of these vultures essentially consist of subadults. The Eurasian Griffon vulture presence, especially as wintering or vagant, was already recorded in other African countries (both from West and from Central Africa), i.e. Mauritania (Browne 1982, Gee 1984, Layna 1997), Central African Republic (Carroll 1988, Dowsett et al. 1999), Senegal (Dupuy 1976, Sauvage & Rodwell 1988, Morel & Morel 1990, Rodwell et al. 1996, Barlow et al. 1999), Sudan (Nikolaus 1987), Chad (Salvan , SI/SIC 2000), Niger (Shull et al. 1986, Newby et al. 1987, Giraudoux et al. 1988, Crisler et al. 2003), Nigeria (Strandberg et al. 2007) and Gambia (Alonso 1984, Barlow et al. 1999, Camiña 2004, Barlow 2005, Roy 2006). During the autumn migration, more than 5000 Eurasian Griffons fly across the Gibraltar Strait (Camiña 2004), the most important bird migration corridor in Western Europe (Zalles & Bildstein 2000), that is close to one of the biggest European population of Griffon vulture (Cadiz province in Spain), where almost 2000 breeding pairs are known to be present (del Moral 2009, Garrido & Romero 2009). The increasing of Eurasian Griffon wintering individuals in Africa suggests that the blow up of its population in Spain is the cause of its movement pattern change, jointly with the global climate change, as also reported for the several observations of Rüppell s Griffon (Gyps rueppellii). The latter is a species originating from sub-saharan Africa, that has been regularly recorded now also in the Iberian Peninsula (De Juana 2006, Gutiérrez et al. 2010, Ramírez et al. 2011, Gutiérrez et al. 2013, Godino & Machado 2015). These observations of European Griffon Vultures in Ghana could represent a sign of the winter range expansion of the species, or allow us to hypothesize that this species can be considered regular in West Africa region (Strandberg et al. 2007). Ack n o w l e d g m e n t s. We would like to thank the Mole National Park staff for their availability and assistance during the field surveys, F Angelici for field help, and two anonymous referees for having considerably improved the submitted draft. References Alonso JC Sur les quartiers d hiver des Vautours fauves migrateurs. Alaiiilii 52: Barlow C, Wacher T, Disley TA Field Guide to the Birds of the Gambia and Senegal. Mountfield: Pica Press. Barlow CR A single European Griffon takes command over two Lappet-faced Vultures at the feeding table in the Gambia. Vulture News 53: 30. Bernis F Migration of the Common Griffon Vulture in the Western Palearctic. In Wilbur SR, Jackson JA Eds, Vulture Biology and Management. 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