Black Howler monkey, juvenile male.

Six groups of howler monkeys (three in cocoa plantations and three in forest) will be followed for three days, every two months, during one year, to assess their behaviour, ecology and primary seed dispersal. Additionally, variables related to seed dynamics and plant regeneration will be compared in three types of environment: cocoa plantation with monkeys, cocoa plantation without monkeys and continuous forest.

The specific questions asked in this project are:

1) What role do black howler monkeys play in the regeneration of plant species through seed dispersal and/or through soil-nutrient enhancement? This will be assessed by quantifying the primary seed dispersal, and the seedling bank under monkey sleeping sites vs. control sites, in the three environments (plantations with monkeys, plantations without monkeys and forest). Additionally, nutrient analyses will be carried out for soil collected under monkey sleeping sites (where most of the defecations are deposited) vs. control sites, in the three environments.

2) What biotic and/or abiotic factors affect the post-dispersal fate of seeds defecated by howler monkeys? This will be assessed by conducting manipulative experiments to quantify seed survival, seed germination, and seedling survival and growth, for three focal tree species dispersed by the monkeys, in the three environments.

3) Is the behaviour and the use of space and food resources of howler monkeys affected by the conversion of forest into shaded cocoa plantation? This will be assessed by recording, for one year, detailed information on the behaviour of three monkey troops living in cocoa plantations and three troops living in continuous forest sites.

Environmental education program:

An important aspect of this project will be showed to local farmers, and the rural community in general, all the information about how the black howlers monkeys are playing an important ecological role by promoting the regeneration of native tree species in the shaded cocoa plantations and in the continuous forest.

The specific activities are:

1) We going to prepare educational talks, posters, fliers, videos and photographic calendars, to distribute in the local communities. The educational talks will be related with the advantages and benefits of maintaining howler monkey populations and shade trees on their cocoa plantations.

2) To the children and young’s people, the education effort will be focused over the elementary schools near the study area. We consider that the teaching method should consist of activities such as games, storytelling, images and movies, with emphasis on the importance of preserving the black howler monkeys of the region.