Curu, Costa Rica

The focus of the research is on the human-nonhuman primate conflict, in which trash raiding behaviors have become a serious issue for not only the primates but for humans as well. New trash containment huts were designed by Dr. Baker as a measure to help keep the wildlife out and have been a success with a few modifications. On this trip to Curu, we documented which trash huts the animals were able to get into and which trash huts were more effective at keeping the animals out. We also documented the behavior and interactions of the monkeys between troop members and humans. We collected data on the types of food the monkeys were raiding and also being offered by visitors and park staff. We then use this information to look for behavior trends and create ways of resolving the issues we see during data collection. We do this by working with the reserve's staff and through tourist education about the effects of feeding wildlife and improper trash disposal. 

 

Research Methods

All of our data is collected within the central tourist area of Curu, as we are looking at the interactions between monkeys and tourists, it is important for our data to be collected where the majority of tourists congregate.  The picnic area is the main location where monkeys intersect with humans, picnic food, and trash.  Having this specific area to remain in also allowed us to record the spread of monkey groups. 

While collecting data, we work in pairs to have one person looking at the monkeys and the second person recording the behaviors seen.  In five minute intervals, we record each monkey one time, tallying their activity as one of the following behaviors; Feed (Natural Food, Provisioned Food, Trash, or Given Food), Forage/Locomote, Rest, Social Friendly, Social Aggressive, Raid (Trash, or Picnic Food).  For each five minute time period, we should have counted each monkey in the group we are observing one time.

 

Results

Trash Raiding

There are currently two types of trash huts that are in place at Curu, the steel mesh and wood hut (which is found throughout the main tourist areas) and the enclosed wooden hut placed at cabin #5. The trash huts were built to enclose trash, recycling, and compost have been successful for keeping the monkeys from raiding.  The monkeys are unable to open the clips holding the trash hut doors closed.  The monkeys do however show a strong interest in foods discarded inside the trash huts. In order to determine if the huts were effective, we baited the trash hut at Cabin #5 with bananas to document the reaction from monkeys. The monkeys showed interest and attempted to raid the hut but were unsuccessful, as were the raccoons which are also a problem at the reserve. We have seen a tremendous amount of tourists feeding the animals, and are getting close to enough to monkeys and raccoons to hand feed them.  People visiting Curu often reach out to monkeys holding food in their hands so they are able to take a close up photo or selfie. This is dangerous as the monkeys are becoming increasingly more aggressive with humans. The data suggests that the monkeys seem to be staying in the main tourist area for longer periods of time each visit, perhaps because there is much more food being offered to them.  They are also much more spread out than in the past.  Individuals in the group could be as far as 200 meters away from each other. 

 

The Problem

When people actively feed monkeys or leave food out for them daily, the monkeys begin to expect this as a food source.  This causes the monkeys to become aggressive when they are not fed.  Feeding the monkeys also causes aggression toward each other, for example, when one monkey has a human snack such as a bag of chips, troop members will often fight over the chips! We have documented fighting between both conspecifics and entirely different species of animals over a single bag of chips!  The nutritional impacts on monkeys can become a serious health risk.  If the monkeys fill up on human snacks, they begin eating much less of their natural foods which hold important nutrients.  Other health risks include possible disease spread.  Humans and monkeys can become very sick from viruses or bacterium which can be passed between species (monkeys and humans can share diseases with one another). The best way to prevent the interspecies spread of disease is to avoid close contact with monkeys and other animals.

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You can help!

You can help prevent these issues when traveling by following a few simple tips:

• Dispose of your trash in the proper containers. If there are no recycling or compost bins, take them home with you to dispose of them properly.

• Look for and document animals’ natural behaviors. For example, White Faced Capuchin Monkeys fur rub with citrus, social groom each other, and forage for natural foods, use the opportunity to look for these behaviors!

• DON’T FEED WILD ANIMALS and Don't attempt to take a selfie with a wild animal as this encourages the feeding of wildlife. 

• Share what you’ve learned with other tourists around you.