Kordofan Giraffe (Giraffa camelopardalis ssp. antiquorum) Appendix 1. Historic and recent population size estimates of Kordofan Giraffe Historic In the 1980s and 1990s, numbers were estimated at more than 13,704 (1,757 in CAR; ca. 1,600 in Cameroon; 890 in Chad; 419 in DRC and 9,038 in South Sudan), whilst limited data are available for some areas within these countries. An estimated 1,000 Giraffe occurred in Cameroon in the late 1950s (Dagg 1962; Jeannin and Barthe 1958). East (1999) reported that Waza National Park protected an important and viable Giraffe population. From the early 1960s to the early 1990s, Giraffe in the park were generally estimated to number between 1,000 and 2,000 individuals (East 1999). Population trends show a decline in Giraffe numbers from 1962 to 1977. The Giraffe population of Waza National Park was estimated at approximately 2,000 individuals in 1962 (Flizot 1962). In January 1977, van Lavieren (1977) estimated approximately 1,091 Giraffe, while an aerial survey conducted in December 1977 estimated approximately 1,262 Giraffe (Esser and van Lavieren 1979). This apparent decline was likely due to the rinderpest outbreak of 1968 and the drought of 1972-1973 (Vanpraet 1976; Beauvilain 1989). After being stable between 1977 and 1980 (Ngog 1983), the Giraffe population of Waza National Park appeared to increase somewhat over the next decade. Aerial sample counts of the park carried out in 1991 estimated approximately 1,516 Giraffe (Tchamba and Elkan 1995). The first documented ground surveys of Benoue National Park was conducted in 1975 and estimated the Giraffe population at approximately 17 individuals (Stark 1977). An estimated 5,000 – 6,000 Giraffe occurred in Chad and the CAR in the late 1950s to early 1960s (Blancou 1963, 1958; Dagg 1962). Anecdotal records indicate that the Giraffe population in the CAR was decimated by illegal hunting in the following years (Happold 1969). According to Happold (1969), few Giraffe occurred in the Yata N'Gaya Reserve and the Andre Felix National Park in the north-east of the CAR by the late 1960s. Aerial counts carried out in the northern CAR in 1985 covering national parks, hunting reserves and community hunting areas, estimated the occurrence of some 1,757 Giraffe in the region (Douglas-Hamilton et al. 1985). Of these, 1,731 were estimated to occur in Manovo Gounda St. Floris National Park and 26 in the Vassako-Bolo Nature THE IUCN RED LIST OF THREATENED SPECIES™ Reserve in the heart of the Bamingui Bangoran National Park (Douglas-Hamilton et al. 1985). The main surviving Giraffe population in Chad occurs in and around Zakouma National Park in south eastern Chad (East 1999). Although East (1999) suggested that Giraffe populations elsewhere in the country are generally low and decreasing, knowledge regarding their occurrence and distribution remains limited. Prior to the 20th century, vast herds of Giraffe were found in central Chad (GIWA 2004). An estimated 5,000 – 6,000 Giraffe occurred in Chad and the Central African Republic (CAR) in the late 1950s to early 1960s (Blancou 1963, 1958; Dagg 1962). Although anecdotal records indicate that Giraffe were heavily hunted in the following years, subsequently reducing their numbers in northern CAR, Giraffe numbers were said to have increased in south eastern Chad (Happold 1969). Since the mid-1980s, wildlife censuses of Chad’s Zakouma National Park have been undertaken at irregular intervals and with different sampling rates across different times of the year, resulting in widely varying population estimates for Giraffe. However, the general trend indicates an increase in Giraffe numbers since the mid-1980s while numbers appeared to remain stable throughout the 1990s. The first aerial survey of Zakouma National Park was conducted in 1986 and estimated approximately 300 Giraffe (Bousquet 1986). In 1991, the Giraffe population was estimated at 890 individuals (Bousquet 1991), in 1995 at 800 Giraffe (Dejace et al. 1995), and East (1999) estimated the Giraffe population at approximately 839 individuals. In the 1950s, Giraffe were distributed throughout the Garamba National Park in DRC, but at somewhat lower density in the north-west, due to illegal hunting (Verschuren 1958). Verschuren estimated at least 300 Giraffe in the park and noted that counts by Cornet d’Elzius had observed at least 60 Giraffe in the Domaine de Chasse Gangala-na-Bodio to the south of the park (East 1999). The presence of a large elephant population has opened the habitat over the last few decades, resulting in Giraffe largely moving into the peripheries of the park and the adjacent reserves, where woodland density is higher (Amube et al. 2009; De Merode et al. 2000; East 1999). Recent Giraffe in Cameroon were largely restricted to protected areas by the late 1990s, when an estimated 1,360 individuals occurred in the country (East 1999). Waza National Park remained an important refuge for Giraffe, while the species occurred at lower densities in Bouba Ndjida, Benoue and Faro National Parks, and the adjoining hunting zones of the North Region (East 1999). Giraffe in Waza National Park showed a declining trend since the 1991 census. A wildlife survey of the Park conducted in 1994 estimated the Giraffe population at approximately 340 individuals (East 1999). However, as this census concentrated mostly on areas around the park's waterholes (East 1999), this could have been an undercount. During ground surveys of Benoue National Park and adjacent hunting zones one and four conducted in 1999, four Giraffe were observed in the park, while no Giraffe were recorded in the hunting zones (Gomse and Mahop 2000). Following a ground survey of the same area in 2004, Donfack and Tsakem (2004) reported insufficient observations of Giraffe. In 2007, eight Giraffe were observed during ground surveys of Benoue National Park, while no Giraffe were recorded in the two hunting zones (Tsakem et al. 2007). Trends in large mammalian density in the northern CAR from 1985 to 2011 showed a decline in Giraffe numbers of almost 70% (Bouché et al. 2011). Aerial counts carried out in 2005, covering national parks, hunting reserves and community hunting areas, estimated a total of 535 Giraffe remaining in the area (Bouché et al 2009). Of these, 254 individuals were estimated to occur in Manovo Gounda St. Floris National Park and 281 individuals in Bamingui Bangoran National Park, of which 12 occurred in the Vassako- Bolo Nature Reserve (Bouché et al. 2009; Renaud 2005). In the new millennium, an aerial survey estimated the Giraffe population of Zakouma National Park at approximately 800 individuals (Dejace et al. 2000). However, in the same year, Planton (2000) counted a mere 154 Giraffe inside the park, although, compared to the general trend throughout the years, this appeared to be an undercount. Mackie (2002) estimated the Giraffe population at approximately 942 individuals. This was however likely an overestimate as the majority of Mackie's observations was conducted in the north-eastern parts of Zakouma National Park, where Giraffe concentrate, and then extrapolated to the rest of the park (Fay et al. 2005, Potgieter et al. 2009). An aerial count of Zakouma National Park in 2005 estimated the Giraffe population at 292 individuals (Fay et al. 2005), while the estimated population count for 2006 estimated 383 Giraffe (Fay et al. 2006). A total of 612 Giraffe were counted during an aerial survey in 2009 (Potgieter et al. 2009). According to the survey report, the 2009 estimate could have been a slight undercount as the authors noted that Giraffe were particularly cryptic from the air when they take to the shade of large trees (Potgieter et al. 2009). Aerial survey counts for 2010 indicated the Giraffe population at approximately 572 individuals (Potgieter et al. 2010), while the estimated population count for 2011 estimated 753 Giraffe (Potgieter et al. 2011). Potgieter et al. (2011) suggested that this is likely to have been an undercount. The first systematic aerial census of Garamba National Park, DRC, carried out in 1976, estimated the Giraffe population at 350 individuals (Savidge et al. 1976). The same method was subsequently applied from 1983 to 2004. Throughout most of the 1980s and 1990s, surveys also included full coverage of the more wooded surrounding reserves, though visibility is sometimes limited. Systematic sample counting in Garamba National Park, even with high density stratification of the southern sector, yielded fairly high standard errors for species with low numbers and clumped distribution, including for Giraffe. As a result, fluctuations in numbers resulted, but no significant in reduction in numbers occurred until the effects of increased illegal hunting resulted during the civil unrest. Current aerial surveys are total counts over the southern sector and parts of the park, and this method gives only minimum numbers and likely more may be present than observed. See table below for aerial survey figures for Giraffe from Garamba National Park and reserves from 1976 to 2012. Year Garamba SE Reserves (DCS) Source NP 1976 350 ±250 Not surveyed Savidge et al. 1976 1983 175 ±163 20 Hillman et al. 1983 1984 237 ±144 0 in part DC Hillman Smith 1989 1986 153 ±140 13 Hillman Smith 1989 1991 346 ±203 46 Smith et al. 1993 1993 347 ±419 0 Smith et al. 1993 1995 178 ±210 52 Hillman Smith et al. 1995 1998 144 ±73 Not surveyed Hillman Smith et al. 2003b 2000 118 ±64 Not surveyed Smith and Hillman Smith 2000 2002 62 ±13 Not surveyed Hillman Smith et al. 2003b 2003 62 ±75 Not surveyed Hillman Smith et al. 2003b 2004 185 ±152 Not surveyed Hillman Smith 2004 Garamba NP (South) 2005 48 Not surveyed De Merode et al. 2005 2006 52 18 in parts of DCs Emslie et al.
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