Tuesday, January 14, 2014

Official Hiatus

If you are still following, you may have noticed that it's been nearly a year since I last posted. I have several barely-complete to nearly-complete posts that are still drafts...but never got the time to finish them.

Anyway, for now SpiderMonkeyTales is on hiatus. I have a new website and e-portfolio I created to do e-portfolios with my primate class at: http://mrodrigueseportfolio.wordpress.com/. I will be sharing primatology content and writing a post for every assignment my students are doing. So start following me there to keep up with my recent primatological writing!

I'm undecided about whether or not I will return to actively blogging on SpiderMonkeyTales. But I will be doing a guest post for BANDIT, and of course posting on the new e-portfolio site this semester. Wordpress is a major pain, and I am missing the simplicity of blogger. But whatever I decide to do, SpiderMonkeyTales will stay up. Re-reading my old posts made me very nostalgic, and will always remain a record of my dissertation fieldwork experience.

My beautiful bonobo friend Lady and me

Wednesday, January 9, 2013

The Party Tree (aka my favorite Ficus)

I have several favorite trees at El Zota. But this Ficus (fig) tree is my absolute favorite. There are a lot of things to love about this tree--it's roots are beautiful, it's on the station's grounds, and the gazebo in the lagoon is an ideal vantage point to watch it. But the reason I love it is because when it fruits, it becomes a popular hotspot for the monkeys and other wildlife.

Ficus trees fruit asynchronously. Rather than fruiting around the same time, each Ficus fruits on its own schedule. This particular tree fruits twice a year, once in the winter and once in the summer, but its hard to predict exactly when. However, if you periodically monitor it, you'll see when little unripe pinkish-white fruits appear. These figs ripen to a deeper pink, and when they do, it's party time! Figs are a keystone resource among primates in many locations, and are found throughout the tropics (there are a number of different species, so the fruit varies between species and among habitats--while this tree produces small pink fruits, other Ficus trees in this forest produce large green fruit). When the fruit ripens, it's a good source of sugar and carbohydrates (essential for highly frugivorous spider monkeys!). But, figs also contain protein (due to the presence of fig wasps that have a symbiotic relationship with the fruits) and calcium, which isn't present in a lot of fruits. So, they are a great resource, and when a fig tree fruits, it's absolutely laden with fruit--until the hungry frugivores completely deplete it (the figs on this tree only last for a few days once they ripen--after that, it's pretty picked through, and then usually howler monkeys and other less picky eaters consume the fruit that didn't properly ripen).

I call this tree the "party tree" for several reasons. First, because when it is fruiting, it attracts all three species of monkeys, as well as coatis, birds, and other frugivores, and it tends to be a noisy and festive attraction. Second, subgroups of spider monkeys are also known as parties, and I like the play on words when I talk about spider monkey parties. Also, my friend Stacy and I had a running joke about trying to identify the community members. Because spider monkeys are in dispersed, fission-fusion communities, the whole community is rarely (if ever) together as a whole. Instead, community members travel in flexible subgroups that are always changing. These subgroups are usually fairly small (mean subgroup size is usually 2-3 individuals, excluding infants who travel on their mothers), but occasionally can be larger, particularly when multiple subgroups converge at key fruiting trees. This community has approximately 35-40 individuals. However, the largest subgroup I've seen was about 15-20 individuals. This makes it really difficult to assess how many communities are present at El Zota, and identify the boundaries of the different communities territories. Furthermore, Stacy and I were both studying females and juveniles--which don't frequent the edges of territories as frequently as the males. So, Stacy and I had a running joke about how we would identify community membership--we talked about throwing a spider monkey block party, where we'd serve fermented fruit, and give the spider monkeys name tags and sharpies, so that they could write their names and community identify with their prehensile tails.

Okay, so obviously, that was a bit of anthropomorphic silliness that could never happen. However, on my first trip to El Zota, we had the next best thing. We were only there for a few weeks, over winter break (Dec 2005-Jan 2006--seven years ago!). During that time, I was trying to collect pilot data for my masters project. I didn't know the forest that well, and I had not yet mastered the art of following spider monkeys and navigating swamps. And... I didn't have the best binoculars (I got new ones that spring before returning to El Zota in the summer). All of these factors made identifying individuals and collecting data quite challenging. But then, the figs ripened. And for several days, subgroups of spider monkeys fed, rested, and socialized in the tree for most of the day (and slept in the tree--Stacy could hear them at night/early morning from the cabin closest to the tree). Occasionally they would retreat into nearby trees or travel away briefly (usually when the tree was taken over by a raucous capuchin group), but for most of the day they stayed there (some of them--party composition changed over the course of the day, with some individuals coming and going), affording me great opportunities to see them well, identify females and juveniles, and conduct focal observations. Additionally, it also gave Stacy and me some great opportunities to take pictures! Some of the best pictures of juvenile male Tristan were taken that day.

Tuesday, January 1, 2013

Welcome to the Year of the Chimpanzee!

Barbara King suggests that 2013 should be the Year of the Chimpanzee. I think this is a great idea! The year is starting off with Jane Goodall as the Grand Marshall of the Rose Parade. 

I ended 2012 by finishing and defending my PhD, and now I am onto developing some potential chimpanzee and bonobo projects. So, the Year of Chimpanzee works well with my current interests. But don't worry, I won't be neglecting the spider monkeys... there are always more spider monkey tales to tell!

See some of the links below for more on the beginning of the Year of the Chimpanzee!

And start off 2013 by enjoying this adorable clip of Cy, a male infant chimpanzee at Fongoli!

Sunday, September 16, 2012

Field Journals: Summer 2008

I have been neglecting my blog because I'm am in dissertation crunch time! But I just came across one of my old field journals, so I figured I'd share some of my thoughts from the beginning of my pilot work in the summer of 2008.


I'm so happy, possibly giddy, to be in CR again.  Today I am going to head back to my beautiful, magical spider monkeys!


We got into El Zota yesterday. It's good to return here.  Yesterday afternoon, I saw capuchins and howlers.  And this morning, I took the new Laguna trail (later named Sendero Colorado) and saw spiders monkeys.  They started off alarm-barking, more than I ever remember them alarm-barking before!  There was an adult female with a dorsal infant, another adult female, and then an adult female with a juvenile female.  The female with the infant had Evita-like facial markings, and I think the juvie female is Buttercup (one of my focal individuals from my masters research two years before)!  The others left, but Buttercup and her mom stayed, and Buttercup cam down low and watched me.  It was great!  I was so deliriously happy to see them.


Today I saw a semi-plumbeous hawk (Leucopternis semiplumbea) and a male scarlet-rumped tanager (Ramphocelus passerinii).  I also saw a coati, toucans, capuchins, and plenty of whip-tails (Ameiva festiva).  Yesterday I think I saw a flash of an agouti and had great spider monkey encounters.  I spent an hour with a party containing an adult female (I think Beatrice) and a juvenile female (I think my dear Buttercup!) and a third adult female--she has white markings on her nose that look like sunblock, so I'm going to call her Coppertone (during my dissertation research, she was re-named Leila).  I also ran into a party containing an adult female and a young juvenile-2 male.  Unfortunately, I then fell into the floating vegetation mat swamp, and lost the monkeys.

Later, I also saw howlers, capuchins, and spiders in association together. A juvenile male spider monkey and  a juvenile howler monkey were playing together.  The juvie spider monkey chased the juvie howler, and she appeared scared.  But then, in retaliation, an adult male howler hit the juvenile spider monkey!


I found one adult female spider in the afternoon, in association with howlers and capuchins.

After that, I got busy with a field course and data collection, and the journal-writing stopped. But it's fun to read those recollections from several years ago!

Midwest Primate Interest Group meetings!

In a couple weeks, one of my favorite conferences, MPIGs, is coming up!  I'm really excited for this year, because I have both a podium and poster presentation.  Also, I'm finally going to meet a couple of my fellow primatology bloggers, Raymond of Prancing Papio, and Ashlee of This is Serious Monkey Business.

 Here are my abstracts for the presentations!

Podium Presentation

Seasonality, activity patterns, and cortisol in female spider monkeys in a wet forest environment.

Seasonality plays a crucial role in shaping the ecological context in which individuals live, which in turn shapes their internal processes.  The glucocorticoids, or stress hormones, are crucial in allocating the body’s resources in accordance with ecological demands, and most animal species experience seasonal variation in glucocorticoid concentrations. Here, I report on the effects of seasonality and activity patterns on cortisol concentrations in wild subadult and adult female spider monkeys, at El Zota Biological Field Station in Costa Rica.  Over a 15-month research period, mean individuals rates of time engaged in rest are significantly negatively correlated with mean cortisol concentrations (Spearman’s rho=-0.737, p=0.010. N=11).  No other activity variable was significantly associated with mean cortisol concentrations. Additionally, over the course of a year, the effects of monthly fruit abundance, mean party size, and activity variables were assessed.  Although fruit abundance and party sizes did significantly vary between seasons, cortisol concentrations did not.  Furthermore, in a general linear model, none of these variables significantly explain variation in monthly cortisol concentrations, although a non-significant trend was observed between time engaged in rest and cortisol concentrations ((F=4.703, p=0.082).  These results indicate that in this mildly seasonal environment, variability in fruit abundance and party size has little effect on cortisol concentrations.  Rather, time engaged in rest appears to be the most important factor in affecting individual’s cortisol concentrations.

Poster Presentation

Whinnies, grooming, and estradiol in wild female spider monkeys.

Identifying hormonal correlates of social behavior in primates can help us understand variation in specific social behaviors across individuals.  Here, I report preliminary results of a study of behavior and endocrinology in wild adult and subadult female spider monkeys from El Zota Biological Field Station, Costa Rica, over a 15-month period.  Estradiol concentrations were assayed from fecal samples collected from recognized females using Enzyme-immunoassay (EIA) techniques. Over the entire research period, mean individual rates of whinny vocalizations were significantly correlated with mean estradiol concentrations (Spearman’s rho=0.818, two-tailed p=0.002, N=11).  Furthermore, both whinny rates (Spearman’s rho=-0.755, two-tailed p=0.007, N=11) and estradiol concentrations (Spearman’s rho=-0.764, two-tailed p=0.006, N=11) were significantly negatively correlated with mean grooming rates.  These findings cannot be accounted for by differences in age, reproductive state, or parity.  Previous studies have indicated a sex difference in whinny production rates, with females producing more whinnies than males. The results of this study suggest that endogenous hormonal factors may affect whinny production, and these factors may underlie the pronounced sex differences observed for this vocalization. The negative relationship between whinnies and grooming indicate that whinnies may serve as a form of “vocal grooming” that plays a role in maintaining social bonds in a less time-exhaustive manner.  

Thursday, June 21, 2012

Congratulations, former field assistants!

Three of my fabulous field assistants have been accepted to graduate school, and have exciting research plans!

Emily "Little Chair" Stulik will be pursuing a Masters in Biology at Indiana-Purdue University to study herpetology with Dr. Bruce Kingsbury. She plans to focus her research on either Massasauga rattlesnakes in Michigan or river turtles in Indiana.

Anna "Fondles Poo" Kordek will be pursuing a Masters in Anthropology at Northern Illinois University with Dr. Leila Porter. Anna plans to study captive bonobo endocrinology, and hopes to eventually study bonobos in the field as well.

Lindsay "One Feather" Mahovetz will be entering the Psychology program at Georgia State University to study ape cognition with Dr. Bill Hopkins.  She plans to study great apes at the Language Research Center, Yerkes Primate Center, and Zoo Atlanta.

Congratulations, ladies!  "Sings with Monkeys" is very proud and excited about your future research endeavors! Of course, I am slightly disappointed that none of you are planning to study spider monkeys, but...  I'm also envious of Anna, because I too have dreams of studying captive bonobos at some point!   And hopefully someday you will all get to return to El Zota to see how our beautiful monkeys are doing!

Sunday, June 17, 2012

Re-wilding captive animals is a risky endeavour

I just read about Damien Aspinall's plans to reintroduce many of the Aspinall Zoo's animals, including gorillas, langurs, and gibbons, as well as Mark Bekoff recent blog post praising these efforts.

Quite honestly, I have some serious concerns about these reintroductions, and am appalled that a prominent ethologist is so uncritically supportive of these efforts.  The motivation is one I understand, although I do not agree with either Aspinall or Bekoff's perspective on the efficacy and ethics of zoos (both have a very negative view on zoos efficacy and ethics).

In theory, re-introductions sounds like a wonderful, beautiful idea.  Take animals whose ancestors were wrongly taken from their kin and native environment, and return them so that they can be wild again.  This is an idea that has inspired me from the very first time I watched Born Free, and when I became interested in primatology, the Golden Lion Tamarin project was my inspiration.

Because of my passion for reintroductions, I audited a course on Wildlife Reintroductions with Dr. Benjamin Beck, one of the foremost experts on the subject.  I read the literature on primate re-introductions, focusing on ape reintroductions, and eventually co-authored Best Practice Guidelines for Ape reintroduction.

And honestly, while I absolutely would love to see re-introduction programs succeed, they have very low success rates, and in many cases will be scary and traumatizing to the animals involved.  Re-introduction of birds and reptiles have higher success rates than mammals, and highly social mammals such as primates have some of the greatest obstacles and lowest chances of success.  The best candidates for re-introduction are usually wild-born sanctuary animals (who may have some memory and experience of the wild).  Individuals who have spent their whole lives in captivity, particularly those that are very human-oriented, are poor candidates for reintroduction.  Most re-introduced animals have short lifespans, are at risk for starvation, predation, and attack by wild members of their own species.  Furthermore, particularly with primates, and especially with great apes, there is a risk of spreading human-contracted diseases to wild populations.

Ultimately, while I do believe that carefully planned reintroductions can be successful, and in particular have value for increasing wild populations numbers if the introduced animals are able to live long enough to reproduce, I do not think it is a solution for individual animal welfare.  While the idea assuages the guilt that humans may have for the past atrocities of capturing wild animals, and of keeping their descendants caged/confined for human purposes, it may not be in the animals' best interests.  Particularly for human-oriented animals who have formed bonds with human caretakers, release into the wild, even in a soft release (a soft release is when animals are given post-release support and monitoring), is traumatizing, and in my opinion, may be downright cruel.

If you are further interested in this topic, I highly suggest reading the following:

Beck B, Walkup, K, Rodrigues, M, Unwin,, S, Travis, D, Stoinski T. 2007. Best Practice Guidelines for the Re-introduction of Great Apes. IUCN/SSC Primate Specialist Group, Gland, Switzerland.
Full PDF available at http://www.primate-sg.org/BP.reintro.htm

IUCN (1998). Guidelines for Reintroductions. Prepared by the IUCN/SSC Reintroduction Specialist Group, IUCN, Gland, Switzerland and Campbridge, UK.

Also, if you are interested in my perspective on zoo goals and their efficacy, check out these previous posts:
Do Zoos Accomplish their Goals?
Zoo Goals: Conservation, Education, and Research
The Efficacy of Zoo Education: Empirical Evidence