Ateles hybridus, Geoffroy Saint-Hilaire, 1829

Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Atelidae, Handbook of the Mammals of the World – Volume 3 Primates, Barcelona: Lynx Edicions, pp. 484-549 : 541-542

19 .

Variegated Spider Monkey

Ateles hybridus

French: Atele varié / German: Brauner Klammeraffe / Spanish: Mono arana jaspeado Other common names: Brown Spider Monkey (brunneus)

Taxonomy. Ateles hybridus 1. Geoffroy Saint-Hilaire, 1829 ,

valley of the Rio Magdalena, Colombia. Restricted by R. Kellogg and E. Goldman in 1944 to La Gloria, Rio Magdalena, elevation 45 m.

Two subspecies are recognized.

Subspecies and Distribution. A. h. hybridus 1. Geoffroy Saint-Hilaire, 1829 — N Colombia (from the right bank of the Rio Magdalena, N to the S slopes of the Sierra Nevada de Santa Marta and the N of the Serrania de Perija, and in the middle Rio Magdalena Valley at least to the departments of Caldas and Cundinamarca; two populations on the slopes of the Cordillera Oriental on the Venezuelan border (one in the Rio Catatumbo watershed in the Norte de Santander Department and the other in the NE piedmont forest in Arauca Department) and N & NW Venezuela (along the SE part of the Cordillera de la Costa in the states of Miranda and probably Vargas, and on both sides of the Venezuelan Andesin the states of Zulia, Tachira, Mérida, Trujillo, Portuguesa, Apure, and Barinas, in the E in the piedmont and lowland forests of San Camilo and Ticoporo, and in the Win the piedmont forest around S Lake Maracaibo to the Sierra de Perija). A. h. brunneus Gray, 1871 — N Colombia in the departments of Antioquia, Bolivar, and Caldas, between the lower rios Cauca and Magdalena.

Descriptive notes. Head-body 47-50 cm (males) and 45-48 cm (females), tail 76— 81 cm (males) and 74-76 cm (females); weight 7-9-8-6 kg, (males, n = 2) and 7-5- 10-5 kg (females, n = 7). The Variegated Spider Monkey is pale wood-brown above, with a darker brown head, and whitish or buffy below, including inner sides of limbs and ventral surface of the tail. It has a distinct white triangular patch on the forehead. Some individuals have grayish-blue eyes. In the nominate subspecies, hindlimbs are usually lighter and similar in color to the back, but knees tend to be darker. The belly varies from white with brownish shades to a light yellow. Ventral hair ofthe tail ranges from yellowish to buffy light brown. In the “Brown Spider Monkey” (A. h. brunneus), exterior color of limbs, back, and feet is dark brown. The belly varies from whitish to yellowish, contrasting sharply with the brownish sides,tail, and head.

Habitat. Evergreen, semi-deciduous, riparian, and montane tropical forests at elevations of 20-700 m (nominate subspecies in Venezuela).

Food and Feeding. The diet of the Variegated Spider Monkey in riparian forest fragment at the Hacienda San Juan de Carare on the east bank of the Rio Magdalena, Colombia, was unusual in its relative lack offruit. Averaging observations of males and females, time spent feeding on different items was 48% ripe fruits, 41-42% leaves, 45% flowers, 2% decayed wood, and 4-5% termite soil, seeds and other items. This diet is probably nottypical but a result of a 5-year isolation in a forest fragment. Geophagy during frequent visits to a mineral lick has been reported for a group of Variegated Spider Monkeys in El Paujil Nature Reserve in the Serrania de las Quinchas. Camera trapping recorded visits of 1-29 individuals at the lick on 81 of 379 days. A list of potential feeding trees for the Variegated Spider Monkey in the region ofVenezuela's El Avila National Park was compiled, but no formalstudy ofits feeding ecology was carried out there.

Breeding. Newborn Variegated Spider Monkeys were observed in August in the Magdalena Valley, but no formal study of reproductive behavior has been done.

Activity patterns. Average activity budgets of 9-11 Variegated Spider Monkeys (males and females combined) at the Hacienda San Juan de Carare were c.41% resting, ¢.29% feeding, c.25% of the day traveling, and ¢.5% engaged in social and other activities.

Movements, Home range and Social organization. Subgroupsizes ofVariegated Spider Monkeys averaged 4-5 individuals in Serrania de San Lucas in southern Bolivar. Median subgroup size at Hacienda San Juan de Carare during one year was three adults, and subgroups of less than four individuals accounted for 73% of the observations. Males were more aggressive to females than to males. Males approached females more often but were more aggressive to them. This aggression was offset to some extent by females grooming the males. Aggression between females was uncommon, perhaps due to the relative lack of fruit and the amount ofleaves in the diet reducing competition. Interspecific infanticide and aggression toward infants were reported atthis site, with male Variegated Spider Monkeys attacking infant Colombian Red Howlers ( Alouatta seniculus ) and infant Humboldt’s White-fronted Capuchins ( Cebus albifrons ). Two infanticides and all but one of seven attacks on infants were perpetrated by a subadult male. The single attack on an infant Humboldt’s White-fronted Capuchin was carried out by two adult male Variegated Spider Monkeys. These primates were restricted to a 70-ha forest fragment, and although the reasons for this behavior were unclear, it might have been related to food competition, a pathology, or redirected aggression. Densities of Variegated Spider Monkeys were 9-14 ind/km? in Serrania de San Lucas and 8-2-9-6 ind/km? at Cerro Bran, near Porto Rico, Bolivar.

Status and Conservation. CITES Appendix II. Classified as Critically Endangered on The IUCN Red List, including both subspecies. Principal threats to the nominate subspecies of the Variegated Spider Monkey in Colombia and Venezuela are habitat destruction and hunting for food. Cattle ranching has significantly reduced the extent of lowland forest in Zulia and in piedmont forests of the Serra da Perija where heavy hunting also occurs. In central Venezuela, large expanses once covered by primary forest are now covered by secondary vegetation, resulting in the apparent extirpation of the Variegated Spider Monkey in this region by 2001. Unfortunately, buffer zones surrounding protected areas with known populations of the nominate subspecies (e.g. Guatopo National Park) continue to be cleared for slash-and-burn agriculture and human settlements. Logging also threatens lowland forests of the eastern Andes, San Camilo, and Ticoporo. The Brown Spider Monkey has a small geographic range in a region where forest loss, degradation, and fragmentation are widespread. Remaining populations in areas of Antioquia (e.g. Segovia, Remedios, Maceo, Yondo, Puerto Berrio, and Zaragoza) are surrounded by human settlements, with less than 10% of the original habitat remaining. As a result, the viability of these populations of Brown Spider Monkeysis questionable, and local extirpations are highly probable in the absence of protection. Potential sites for protected areas remain in the Serrania de San Lucas and parts of Nechi in the south of Bolivar and the north of Antioquia departments. The nominate subspecies occurs in Sierra Nevada de Santa Marta, Sierra Nevada del Cocuy, Catatumbo-Bari, and Tama national natural parks in Colombia and Guatopo, El Avila, and Sierra de Perija national parks and Caparo Forest Reserve in Venezuela. It may also occur in Colombia’s Chingaza National Natural Park. Brown Spider Monkeys are found in the proposed Serrania de San Lucas National Natural Park, and in Ciénagas de Barbacoas which is a priority for the creation of a protected area.

Bibliography. Abondano & Link (2012), Bernstein et al. (1976), Bodini & Pérez-Hernandez (1987), Cordero-Rodriguez & Biord (2001), Defler (2003b, 2004), Defler et al. (2003), Di Fiore, Link & Campbell (2011), Di Fiore, Link & Dew (2008), Duque (2007), Green (1978), Hernandez-Camacho & Cooper (1976), Hernandez-Camacho & Defler (1989), Link et al. (2011), Lizarralde (2002), Mondolfi & Eisenberg (1979), Palacios et al. (2009), Portillo-Quintero & Velasquez (2006), Rimbach et al. (2012), Urbani et al. (2008).

Figures

On following pages 14 Brown-headed Spıder Monkey (Ateles fuscıceps) 15 Black Spider Monkey (Areias chamekl. 16 Red-faced Black Spıder Monkey (Areias paniscus) 17 Whne-wmskered Spodev Monkey (Areias margmatus) 18 Whıtebellıed Spıdeı Monkey (Areias belzeburh), 19 Vanegated Spıder Monkey (Areias hybndus)

Subspecies and Distribution. A. h. hybridus 1. Geoffroy Saint-Hilaire, 1829 — N Colombia (from the right bank of the Rio Magdalena, N to the S slopes of the Sierra Nevada de Santa Marta and the N of the Serrania de Perija, and in the middle Rio Magdalena Valley at least to the departments of Caldas and Cundinamarca; two populations on the slopes of the Cordillera Oriental on the Venezuelan border (one in the Rio Catatumbo watershed in the Norte de Santander Department and the other in the NE piedmont forest in Arauca Department) and N & NW Venezuela (along the SE part of the Cordillera de la Costa in the states of Miranda and probably Vargas, and on both sides of the Venezuelan Andesin the states of Zulia, Tachira, Mérida, Trujillo, Portuguesa, Apure, and Barinas, in the E in the piedmont and lowland forests of San Camilo and Ticoporo, and in the Win the piedmont forest around S Lake Maracaibo to the Sierra de Perija). A. h. brunneus Gray, 1871 — N Colombia in the departments of Antioquia, Bolivar, and Caldas, between the lower rios Cauca and Magdalena.