Data Day #1 - Officially

Today was the first day of official data collection.  These past few weeks have been spent habituating our titi families and practicing the methodology, so this was the first time the data we collected would go down in the books as real data.  Today was also our first afternoon shift at Yvaga Guazu.  Three of our five workdays consist of early morning shifts (like real real early...like we get there before the sun does), and on the other two days, we get there around 11 AM and don't leave until about 6 or 6:30 PM.  Got to cover all our behavioral bases.  Got to make sure the monkeys aren't doing crazy stuff when we're not looking.  So today was our first afternoon shift and I think we were all a little nervous.  So far, we've had some pretty sore luck finding our monkeys after 10:30 in the morning - thus the nerves - and today was no exception.  At least for me.  We arrived to our field site around noon (11 was our original goal, but we ran into slight transportation issues), and I spent the next FOUR AND A HALF HOURS searching for my elusive family.  The entries in my field notebook sum up my morning pretty well...

12:24  There's a tree full of vultures at the corner of my territory.  Twelve.  Twelve vultures.  Hope they're not feasting on the tiny carcasses of my monkey family...
1:02  Still can't find my monkeys.  I NEED SOME DATA.  Titis - where you at??
1:58  Why does it smell like bacon?
2:53  No monkeys yet.  Screw this, I'm eating lunch.

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

I finally had a breakthrough around 4:30.  A neighboring titi family began to vocalize, and although my group was unresponsive at first, they eventually chimed in with a reply to the initiators of the bout.  I spotted two individuals (the same two individuals from last Wednesday) in a tree at the northwestern corner of the territory (near the same tree I found those two in last Wednesday).  I saw my male - carrying the infant, as always - but I was still unsure of his companion.  Female?  Subadult?  At this point, there was no way to tell.  As a small, grey juvenile approached the duo, I heard nearby vocalizations from two additional monkeys.  I was really starting to think that these were the two older offspring of my family...staying far away enough to kind of do their own thing, but still close enough to check in with their folks to let them know everything's okay.  These suspicions were confirmed when I noticed my male pass the little baby titi over to the other individual, where I watched the baby nurse.  That's a pretty clear indicator that the duet consisted of my male and my female, with the juvenile sticking close to mommy and daddy.  It was at this point, while my female nursed her youngling, that I witnessed my first case of 'scent marking' behavior.  There are two kinds of scent marking: anogenital rubbing and chest rubbing.  I was witnessing the latter, as my male moved his chest with pressure and friction against a tree branch by sliding his body forward.  Only a few minutes after this behavior, I was able to watch my male and female actively groom one another.  It may have taken me a while to find them, but it was fantastic seeing all these different behaviors.

Female and Male after vocalizing

Grooming session 

Cute little juvenile titi monkey

For the next half an hour or so, I watched my male play with the juvenile, I listened to a few more titi conversations, and I observed my family forage in their new favorite paraíso tree.  And that's where I left them.  I had just found my monkeys about an hour before, but it was already time to pack up and leave for the day.  I wasn't able to collect as much data as I would've liked, but the data I did collect was solid and I was confident in my work.  Goal for next time?  Find those damn monkeys sooner!

Beautiful sunset at Yvaga Guazu

FUN SCIENCE FACT #8:  To avoid predators, a mother Slow Loris (genus Nycticebus) licks the offspring with her toxin-laced saliva before sending them off to search for food.  What a good mom.