Research Plan!

 I want to be able to measure behavioral differences between the two species --- how their interactions with the new stimulus differ between each other and what that may mean. How quickly do the animals investigate the new items? How quickly do they figure out that they hold food and how to get into them?How quickly and how well do they figure out, if they do, that only certain containers hold a reward? And finally, how well, if they do, do they remember everything they have learned from their previous encounters with the stimulus, after a period of absence from it?

So, the stimulus and protocols need to be the same for both, which shouldn't be a problem as the stimulus will be designed to fit both primate species capabilities. 

At first, I was thinking of doing plastic boxes with a lift lid. This would work easily as far as putting food items inside and watching them interact with them. However, after purchasing a lift-lid box, filling it with tuna and cat treats and presenting it to my cat and foster kittens, I am now concerned that the box, or at least this type of box, will be too easy to open.

After consulting with the senior keeper for the Oakland Zoo's primates, I have confirmed that I will be unable to use anything plastic, with hinges, or with treated wood as the red-tailed monkeys are voracious chewers, (absolutely destroyed Kong dog toys!) so the above idea has been ruled out. Also, she was concerned the monkeys may get their heads stuck in the jackfruits! So unless I can find small ones, they are also ruled out.

That leaves baskets, and card board boxes, the later of which will be easy to paint, and otherwise use and transport, so that is looking attractive. However, the lemurs and monkeys haven't had soft woven baskets before, so that may be a more intriguing material to them. But of course, it may not work out if the red-tailed monkeys decide to cause trouble with it.

The keepers have suggested PVC, which would hold up well against the red-tails. However, I am unsure of how well non-toxic paint will stick to them, and how to secure the food items inside, without making them impossible to open by anything other than a human. Also, I have been told the lemurs do not like anything with small holes, so drilling into them is a no-go. Are they trypophobic, lol? So we shall see! Consulting further with the zookeepers, and I have set up a virtual meeting with my faulty mentor.

(Screenshot from my profile on SURF!) 

Link: https://surf.berkeley.edu/fellows/