Red-handed howler

Red-handed howler[1]
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Atelidae
Genus: Alouatta
Species: A. belzebul
Binomial name
Alouatta belzebul
(Linnaeus, 1766)
Red-handed Howler range

The red-handed howler (Alouatta belzebul) is a vulnerable species of howler monkey, a type of New World monkey. It is endemic to Brazil, where found in the south-eastern Amazon and disjunctly in Atlantic Forest between Rio Grande do Norte and Sergipe.[2]

Contents

Distribution and Life History

The red-handed howler is endemic to the states of Brazil, Para, Amapa, Maranhao, Pernambuco, Paraiba, and Alagoas of northern and northeastern Brazil. It lives in the biomes of Amazonian and Atlantic forests which consist of dense forest that are separated by drier areas. These animals can live up to 20 years old [3] and don't mature until later in their life, have a long gestation period, and generally reproduce slower than similar sized mammals of other species [4]. From the births that have been recorded red-handed howlers have quick, quiet births during the day when they are normally active. Once born, if the mother is experienced, it will carry her young ventrally for three weeks and then switch to dorsally once the offspring is slightly more developed [5].

Behavior and Diet

When not foraging red-handed howlers rest in the canopy of mature trees 20 meters from the forest floor [5]. Red-handed howlers also live in social groups of about 7-12 with one or two mature males, females, juveniles, and infants [6].The number one source of food for this species is ripe and unripe fruit and has the highest reliance on this food source out off all the species in this genus. There are a variety of species that provide fruit year round, but the red-handed howler also relies on leaves to supplement the sugars of the fruits with protein. When these food sources were limited the howlers also supplemented their diet with more mature leaves, flowers, woody plant matter, and sometimes fungus to possibly help digest the increased plant matter [7].

Threats

There are numerous threats to the red-handed howler monkey. First, is that they are a large bodied mammal that people hunt for food. Females with young are especially good targets for hunting because the babies can be sold as pets and the mothers can be used for their meat. Slower reproduction of these mammals also prevents them from replenishing the population in response to this pressure. The red-handed howler monkey has one of the smallest ranges out of their genus and these small ranges makes them even more susceptible to threats. Second, is that the Transamazonia and the Belem-Brazilia highways intersect their habitat which causes collisions with automobiles. Third, is the threat from agriculture. Increasing population pressures have forced farmers to clear more land for farming and these clear-cut methods are too much of a disturbance for the red-handed howler. Some small disturbances are tolerated by species that focus more on leaves, but since A. belzebul is mostly frugivorous, it is harder for them to adapt to change. Logging is yet another concern, because it not only disrupts the habitat too much, but it also allows better access to their habitats for hunters by use of the access roads. Fourth, is the habitat fragmentation that comes along with all of these disturbances. If the forest does eventually regenerate, there will still be no way for new howlers to come back into the area and it also prohibits gene flow and the amount of genetic variation will decrease [4]. Lastly, predation can have a large effect on the population. Since the populations are usually in groups in small areas, they are easy prey for animals such tayras There was one study done where tayras found their way onto an island and took out a large portion of the population by hunting together and preying on the family groups in the area [6].

Conservation steps

There are a variety of options that be put into place to help the red-howler monkey recover. First, is to work with landowners to make sanctuaries or protect vital habitat. Since this species relies so heavily on fruit, certain habitat with a variety of fruit producing tree stands should be focused on for protection. Second, if slash and burn methods are needed, farmers could use smaller portions of forest and rotate often to allow for forest regeneration and re population by howlers. Corridors could also be maintained between properties, crop areas, and developed areas. Success has also been documented on the use of ladder bridges across roads to allow red-handed howlers to cross roads safely. Third, translocation is another option that could be used to re populate suitable habitat that animals may not be able to reach because of fragmentation. Translocation could also be a useful tool in allowing gene flow between areas that would generally not mix [4]. Lastly, the genetics of the populations should be monitored to make sure that adequate genetic variability is present to sustain the populations. There are already some of these studies being done using microsatellite loci to determine diversity [8].

References

  1. ^ Groves, C. (2005). Wilson, D. E., & Reeder, D. M, eds. ed. Mammal Species of the World (3rd ed.). Baltimore: Johns Hopkins University Press. pp. 148. OCLC 62265494. ISBN 0-801-88221-4. http://www.bucknell.edu/msw3/browse.asp?id=12100375. 
  2. ^ a b Veiga, L. M., Kierulff, C. & de Oliveira, M. M. (2008). Alouatta belzebul. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 3 January 2009.
  3. ^ Nascimento F.F., Bonvicino C.R., De Oliverira M.M., Schneider M.P.C. (2008). Population Genetic Studies of Alouatta Belzebul from the Amazonian and Atlantic Forests. American Journal or Primatology 70, 423-431.
  4. ^ a b c Horwich R.H. (1998). Effective Solutions for Howler Conservation. International Journal of Primatology 19,3.
  5. ^ a b Camargo C.C., Ferrari S.F. (2007). Observations of Daytime Births in Two Groups of Red-Handed Howlers (Alouatta belzebul) on an Island in the Tucurui Reservoir in Eastern Brazilian Amazonia. American Journal of Primatology 69, 1075-1079.
  6. ^ a b Camargo C.C., Ferrari S.F. (2007). Interactions between tayras (Eira barbara) and red-handed howlers (Alouatta belzebul) in eastern Amazonia.
  7. ^ Pinto L.P., Setz E.Z.F. (2004). Diet of Alouatta belzebul discolor in an Amazonian Rain Forest of Northern Mato Grosso State, Brazil.
  8. ^ Goncalves E.C., Silva A., Barbosa M.S.R., Schneider M.P.C. (2004). Isolation and characterization of microsatellite loci in Amazonian red-handed howlers Alouatta belzebul (Primates, Plathyrrini). Molecular Ecology Notes 4, 406-408.

External links