|
|---|
Warning: Undefined property: stdClass::$Photo1 in /var/www/vhosts/virtualzoo/classifications/display.php on line 584
| Subspecies: | Unknown |
|---|---|
| Est. World Population: | |
| CITES Status: | NOT LISTED |
| IUCN Status: | Vulnerable |
| U.S. ESA Status: | NOT LISTED |
| Body Length: | |
| Tail Length: | |
| Shoulder Height: | |
| Weight: | |
| Top Speed: | |
| Jumping Ability: | (Horizontal) |
| Life Span: | in the Wild |
| Life Span: | in Captivity |
| Sexual Maturity: | (Females) |
| Sexual Maturity: | (Males) |
| Litter Size: | |
| Gestation Period: | |
Habitat:
Night monkeys typically occur in primary and secondary forest (including disturbed forest and selectively logged forest), seasonally flooded and terra firma, lowland forest, submontane and montane (cloud forests) in Colombia and in the Andes to 3,200 m above sea level (the specifically montane forms are Aotus lemurinus and Aotus miconax) (Hernández Camacho and Cooper 1976, Aquino and Encarnación 1994a, Defler 2004). Aquino and Encarnación (1994b) reviewed the habitat and forest preferences of the genus.
Night monkeys are nocturnal: they are most active at dawn and dusk. During the day, they rest in hollows tree trunks and within dense vegetation” (Tirira, 2007). They are frugivorous; their diet includes fruit, nectar and flowers, leaves, and small animals prey such as insects (Wright 1989; Fernandez-Duque 2007). Aotus azarae and Aotus zonalis has been observed to include a significant portion of leaves in their diet (Hladik and Hladik 1969, Ganzhorn and Wright 1994, Giménez and Fernandez-Duque 2003). The diet of montane night monkeys has been studied by Castaño et al. (2010) in the Western and Central Andes and included 65.8% of fruits, 28.2% of arthropods and complemented its diet with flowers, leaf buds and seeds and Guzman et al. (in review) also reported that montane night monkey fed mostly on fruits and flowers.
They are socially monogamous, living in small groups of an adult pair and offspring of different ages (infant, one or two juveniles and sometimes a subadult. In A. a. azarae, a significant number of adults range alone. They may be subadults that have left their natal groups or older adults which have been evicted from their groups by competitors (Fernandez-Duque and Huntington 2002, Fernandez-Duque 2004). Both sexes disperse. Males care for the infants (carry them) (Rotundo et al. 2002, 2005). Lone adults were observed by Villavicencio Galindo (2003) in northern Colombia. Night monkeys are territorial—groups occupy overlapping territories of 5-18 ha (depending on the species and location) (Wright 1978, 1981; Fernandez-Duque 2007). Wright (1994) and Fernandez-Duque (2007) review the behaviour and ecology of the genus.
Captive male A. lemurinus reach sexual maturity when 2 years old, and captive female A. vociferans and A. nancymaae first breed when 3-4 years old (Dixson 1983, Fernandez-Duque 2007). In the wild, male A. azarae reach adult weight only when about 4 years old, and age at first reproduction is about 5 years of age (Juárez et al. 2003; Fernandez-Duque 2004). A female A. azarae was found to breed for the first time at 58 months of age (Fernandez-Duque et al. 2002). Single offspring are the rule. Wright (1985) recorded births between August and February for A. nigriceps in Peru (Manu National Park), and Aquino et al. (1990) indicated a birth season between December and March) for A. nancymaae in north-eastern Peru. In the Argentinean Chaco, A. azarae shows a peak of births between March and June (Fernandez-Duque 2007).
Size:
Adult male weight average 0.920±0.075 kg (n=7, range 0.608-1.15 kg), adult female weight 0.859±0.088 kg (n=6, range 0.578-1.05 kg) (Hernández-Camacho and Defler 1985). NB: This could refer to griseimembra, considered by Hernández-Camacho and Defler (1985) to be a subspecies of A. lemurinus.
Night monkeys are nocturnal: they are most active at dawn and dusk. During the day, they rest in hollows tree trunks and within dense vegetation” (Tirira, 2007). They are frugivorous; their diet includes fruit, nectar and flowers, leaves, and small animals prey such as insects (Wright 1989; Fernandez-Duque 2007). Aotus azarae and Aotus zonalis has been observed to include a significant portion of leaves in their diet (Hladik and Hladik 1969, Ganzhorn and Wright 1994, Giménez and Fernandez-Duque 2003). The diet of montane night monkeys has been studied by Castaño et al. (2010) in the Western and Central Andes and included 65.8% of fruits, 28.2% of arthropods and complemented its diet with flowers, leaf buds and seeds and Guzman et al. (in review) also reported that montane night monkey fed mostly on fruits and flowers.
They are socially monogamous, living in small groups of an adult pair and offspring of different ages (infant, one or two juveniles and sometimes a subadult. In A. a. azarae, a significant number of adults range alone. They may be subadults that have left their natal groups or older adults which have been evicted from their groups by competitors (Fernandez-Duque and Huntington 2002, Fernandez-Duque 2004). Both sexes disperse. Males care for the infants (carry them) (Rotundo et al. 2002, 2005). Lone adults were observed by Villavicencio Galindo (2003) in northern Colombia. Night monkeys are territorial—groups occupy overlapping territories of 5-18 ha (depending on the species and location) (Wright 1978, 1981; Fernandez-Duque 2007). Wright (1994) and Fernandez-Duque (2007) review the behaviour and ecology of the genus.
Captive male A. lemurinus reach sexual maturity when 2 years old, and captive female A. vociferans and A. nancymaae first breed when 3-4 years old (Dixson 1983, Fernandez-Duque 2007). In the wild, male A. azarae reach adult weight only when about 4 years old, and age at first reproduction is about 5 years of age (Juárez et al. 2003; Fernandez-Duque 2004). A female A. azarae was found to breed for the first time at 58 months of age (Fernandez-Duque et al. 2002). Single offspring are the rule. Wright (1985) recorded births between August and February for A. nigriceps in Peru (Manu National Park), and Aquino et al. (1990) indicated a birth season between December and March) for A. nancymaae in north-eastern Peru. In the Argentinean Chaco, A. azarae shows a peak of births between March and June (Fernandez-Duque 2007).
Size:
Adult male weight average 0.920±0.075 kg (n=7, range 0.608-1.15 kg), adult female weight 0.859±0.088 kg (n=6, range 0.578-1.05 kg) (Hernández-Camacho and Defler 1985). NB: This could refer to griseimembra, considered by Hernández-Camacho and Defler (1985) to be a subspecies of A. lemurinus.
Range:
Montane Night Monkey is distributed in the Western, Central and Eastern Andes mountains from about 1,000 up to treeline elevations of 3,000 to 3,200 m (Hernández-Camacho and Cooper 1986). Following the range map in Defler (2003, 2004), it extends south as far as region of the headwaters of the rios Caquetá and Orteguaza. Tirira (2007) provisionally regards the montane night monkeys occurring in the subtropical humid forest along the Eastern Andes (elevations 940-1,800 m) as belonging to this species, although he points out (p.160) that its identity has yet to be confirmed. Castaño and Cardona (2005) reported nine different localities with montane night monkeys ranging from 970 to 2050 m. There are few records and all are based on sightings in the wild; the few museum specimens have yet to be studied in this regard. The possibility remains that it may be a variant of A. vociferans occurring otherwise throughout eastern Ecuador and adjacent northern Peru (Aquino and Encarnación 1994a), or even an as yet unrecognized, distinct species.
There is only scant information on the elevational distribution of Aotus lemurinus and its distribution limits with Aotus griseimembra.
The species’ extent of occurrence (EOO) and area of occupancy (AOO) are declining. In Ecuador, Sierra (2013) estimated the deforestation rate in the montane forests of the eastern slopes of the Andes to be consistently high from 1990 through 2008. In this period, the percentage of deforested area in these ecosystems changed from 19.6% to 32.2% (or a 64.3% decrease in forested area). Most of the deforested area was used for pastures. Although there are no published current estimates of the deforested areas, if this trend persists, the percentage of deforested area by 2020 would be about 40% (i.e. a further 24.2% decrease in forested cover by 2020).
Another study carried out in the south-eastern Andean slopes Torracchi et al. (2013) calculated a mean annual deforestation rate of 1.87% between 1976 and 2002 in the lower montane forest that is part of the species geographic range. If this deforestation trend persists to date, about 65% of the forest area estimated in 1976 would have been lost by 2002.
In Ecuador, mining is posing an increasing threat to montane ecosystems east and west of the Andes. A large percentage of the forests in the eastern Andean slopes are conceded to mining companies (Vandegrift et al. 2018).
In Colombia, deforestation from 2000 to 2019 in the species’ range has ranged from 4.3% in Cundinamarca to 11% in Norte de Santander (Global Forest Watch 2020).
There is only scant information on the elevational distribution of Aotus lemurinus and its distribution limits with Aotus griseimembra.
The species’ extent of occurrence (EOO) and area of occupancy (AOO) are declining. In Ecuador, Sierra (2013) estimated the deforestation rate in the montane forests of the eastern slopes of the Andes to be consistently high from 1990 through 2008. In this period, the percentage of deforested area in these ecosystems changed from 19.6% to 32.2% (or a 64.3% decrease in forested area). Most of the deforested area was used for pastures. Although there are no published current estimates of the deforested areas, if this trend persists, the percentage of deforested area by 2020 would be about 40% (i.e. a further 24.2% decrease in forested cover by 2020).
Another study carried out in the south-eastern Andean slopes Torracchi et al. (2013) calculated a mean annual deforestation rate of 1.87% between 1976 and 2002 in the lower montane forest that is part of the species geographic range. If this deforestation trend persists to date, about 65% of the forest area estimated in 1976 would have been lost by 2002.
In Ecuador, mining is posing an increasing threat to montane ecosystems east and west of the Andes. A large percentage of the forests in the eastern Andean slopes are conceded to mining companies (Vandegrift et al. 2018).
In Colombia, deforestation from 2000 to 2019 in the species’ range has ranged from 4.3% in Cundinamarca to 11% in Norte de Santander (Global Forest Watch 2020).
Conservation:
This species is confirmed, or may occur, in the following protected areas:
Colombia
Ecuador
It is listed on Appendix II of CITES.
Most urgent is the protection of any forests that provide habitat for populations in northern Colombia. Censuses of populations and habitat are needed to better assess the population status of this species, including the protected areas where the species inhabits as a way of evaluating the effectiveness of their protection. Finally, there is a need to confirm if A. lemurinus is the species that occurs in the eastern Andean slopes in Ecuador.
Colombia
- Puracé Natural National Park (83,000 ha) (in range, Defler 2003, 2004)
- Tama National Natural Park (48,000 ha) (in range, Defler 2003, 2004)
- Serranía de Los Yariguies (56,000 ha)
Ecuador
- Llanganates National Park (219,707 ha) (Tirira 2007)
- Sumaco Napo Galeras National Park (205,249 ha) (Tirira 2007)
- Cofán-Bermejo Ecological Reserve (55,451 ha) (Tirira 2007)
- Cabañas de San Isidro Reserve (1170 ha)
- Yanayacu Bird and Wildlife Reserve (250 ha)
- Sierra Azul Reserve (2500 ha)
It is listed on Appendix II of CITES.
Most urgent is the protection of any forests that provide habitat for populations in northern Colombia. Censuses of populations and habitat are needed to better assess the population status of this species, including the protected areas where the species inhabits as a way of evaluating the effectiveness of their protection. Finally, there is a need to confirm if A. lemurinus is the species that occurs in the eastern Andean slopes in Ecuador.