page_title: Brown howler
section_title: Reproduction
hierarchical_section_title: Brown howler / Behavior / Reproduction
caption_attribution_description: English: Brown howler monkey (Alouatta guariba clamitans) in Monte Alegre do Sul, São Paulo State, Brazil. Male (brownish color) and female (blackish color).
context_page_description: The brown howler, also known as brown howler monkey, is a species of howler monkey, a type of New World monkey that lives in forests in southeastern Brazil and far northeastern Argentina. It lives in groups of two to 11 individuals. Despite the name "brown howler", it is notably variable in colour, with some individuals appearing largely reddish-orange or black.
  The two subspecies are:
  Northern brown howler, listed as critically endangered
  Southern brown howler
context_section_description: It is difficult to breed the genus Alouatta in captivity and therefore the reproduction is relatively unknown. Brown howlers reproduce year round. There seems to be no correlation to birth rates in rainy or dry season or in times of increased fruit or leaves. It is thought that because the brown howler has a folivorous diet, conception is less dependent on maternal conditions.  The average interbirth interval (IBI) for the brown howler is 19.9 months, which is similar to other howler species.  It does not seem that the sex of the infant or the number of females in the population has a significant effect on IBI. The death of an infant will shorten the mother's IBI and seems to be one of the few factors that affects IBI.
caption: An adult pair and a young, also showing some of the distinct color variations in this species
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