A quick picture update from the Bahamas

Posted on April 18, 2017 by colindonihue

There’s lots going on here in the field. We’ve just wrapped up collecting on Eleuthera and Long Island. I’m back on New Providence swapping out crew. Rob left after Eleuthera. He swapped spots with Geoff. We just lost Jon – a champion lizard catcher on Eleuthera and Long. Raphaël is still here and we’re being joined by Angus and Pavitra tomorrow. The rapidly switching roster is actually the least of the logistics worries but today, with twenty-dozen lizards safely ensconced in a cooler on their way back to Boston, I’m finally taking a few deep breaths.

Here are just a few pictures from the field. I’ll bolster them with a prosier post as soon as I can.

Here’s our quarry, Anolis sagrei, the “festive” anole.

And here’s one with dewlap unfurled.

This was Rob’s first time catching Anoles. Here’s his face after his first successful lasso.

Three days later he was catching like a pro while reposed under thorn bushes.

We’re catching a lot of lizards for this study – 120 per island. Here are a few in a lizard bag waiting for sorting.

While we’re catching lizards we’re also gathering data on their behavior and ecology – where they’re piercing and how warm that perch is for example. Here are Raph and Rob typing in some of the data. We’ve got well over 600 observations so far.

We’ve been doing a bit of driving between sites. Not a problem though with scenery like this. Note, the steering wheel is on the American side but the roads are all reversed (Thanks Great Britain). This causes some consternation trying to get used to the unfamiliar lane position with a familiar vehicle layout. Oddly, 2 of the 3 cars I’ve driven this trip have been reversed in this way. This however was the only car with a helpful red arrow to remind me where to be on the road. Luckily for these dirt paths it’s one car at a time no matter the side.

We’ve met a few other friends in the field. Here’s Geoff with a racer snake we found in the forest.

And here’s Anolis angusticeps, the coolest, most secretive anole we’ve seen this trip.

Here’s the final stage – a giant cooler in the back seat of a small sedan to the airport. Just peeking over the cooler in the back there is Jon, the ringer for lizard catching.

Bimini is our next stop for tomorrow! One more push on fieldwork, another ten dozen lizards, and then it’s back to Boston.

Working on Redonda

Posted on February 19, 2017 by colindonihue

As I said in the previous Redonda post, I’m headed to the island in search of the three endemic species of lizards living there. My goal is to gather as much baseline data as possible on the natural history of these lizards so we can come back in a year, or in 10 years and see how they’ve changed without killer rats chasing them and hungry goats munching all of the vegetation.

That’s easier said than done though.

First, here’s a picture of Redonda taken by Dr. Jenny Daltry, the FFI scientist coordinating these efforts (and featured in that video I posted).

1_aerial-view-of-redonda-jenny-daltry-ffi

Photo: Dr. Jenny Daltry, FFI via news.mongobay.com

The first, fairly unmissable thing to notice is that Redonda is surrounded by cliffs straight into the sea. This picture actually shows the pleasant, accessible side of the island! Here’s the other:

Photo from toptenz.net.

So getting onto the island is going to be a bit of a trick. In 1964, the herpetologist that first described Anolis nubilis, Skip Lazell, described making a harrowing jump from boat to shore and scrabbling up a guano-coated sluiceway in order to get to the lizards. Another researcher I talked with tried to swim from boat to island twice and never managed to clamber up those slopes. So, if not by sea, then by air. We’ll be helicoptering into Redonda (!) and, if I have my way, we’ll be blaring the Jurassic Park theme.

In order to get as much of this one-shot data as possible I’m taking along two team members to help out. Geoff Giller is a friend from Yale and a terrific photographer and science journalist. Anthony Herrel, will also be coming along. He’s popped up more than a few times on my blog; we’ve been working together in Greece for the last several years.

We’re going to be on Redonda for 8 days. Yup. Eight days dodging rats and chasing lizards. That should be challenge enough, but to make things more interesting, there’s no fresh water anywhere on the island. We’re going to have to bring all of our food and water to the island via helicopter. Of course, it’s going to be in the 80s the whole time we’re there and with only 1 tree on the whole island, shade is going to be scarce, so I’m thinking we’re going to go through that water pretty fast.

Of course, since there aren’t any people living on the island, there’s no electricity. Normally I’d be kind of excited to be “unplugged” and off the grid for a week but alas, some of my research equipment needs power. Lots of power. So I’ve got a solar array coming along to keep computers and spectrophotometers running. Then there are the cameras. So many cameras. We’re bringing 3 GoPros, 2 DSLR digital cameras, 1 handheld video camera for behavior analyses, and a drone. Power consumption is definitely going to be problematic – I’ve been trying to calculate energy consumption rates for all these things over and over to figure out if we’re going to make it. Then there’s memory storage for all those devices… in all Geoff and I are bringing almost a terabyte of flash cards. Egads.

All of that equipment is going to be worth it though! We’re going to get the first ever comprehensive data on what these lizards look like, how they behave, and how they fit into their current ecological community. The next question is when the community shifts to no longer include these invasive pests, how are the lizards going to adapt? Stay tuned!

Finished my first postdoc!

Posted on January 7, 2017 by colindonihue

I’ve just finished my first postdoc appointment!

Let me qualify that a bit: I’m “finished” in that I’ve been paid all I’m getting paid for that project. Unfortunately, I’ve only completed about half of the work I’m hoping to do for the team, so I’ve really got a long ways to go yet.

Way back in June I started working on a big project in the Losos lab looking at patterns of morphological and genetic variation in a widespread lizard species, Anolis sagrei (also called the Festive Anole) across its range in the Caribbean. The field trip I took to the Bahamas last year was a part of this project.

Anolis sagrei, the Festive Anole

The project is two pronged and there are (were) two of us postdocs leading the charge on the day-to-day work here on campus. I’ve been trying to keep track of all of the questions with data that’s lizard-sized and larger. The other postdoc, Anthony is master of all of the genetic methods and questions about things (much) smaller than lizards.

The festive anole can be found on a whole lot of islands in the Caribbean (and it’s making its way onto the mainland in Central America and the southeastern US). Across that range it can be found in a variety of habitats from mangrove forests or beach scrub all the way to primary old growth forests (where those forests can still be found). The first stage of the project was gathering morphological data on the species across the many different habitats it inhabits to better understand the drivers and extent of the considerable morphological variation we see across these areas.

2015_dec_graham_lab_meeting

Above is just an example of male A. sagrei from three different islands in the dataset. Look at all that variation in dewlap color!

The second part of the project is a massive breeding experiment. We’re trying to look at the reproductive compatibility of different A. sagrei populations that have been isolated from each other for millions of years. Our thinking is that over this time they’ll have evolved differences in body size or dewlap color, for example, that prevent them from interbreeding successfully. The breeding experiment is underway and will be for a while longer.

So, what’s next? Well, last spring I won a three year fellowship from the National Science Foundation to conduct my own research at Harvard. My funding for that project started January first so I’m fleshing out plans for next steps. I’ll update you more on those plans, but it’s going to involve quite a bit more time back in Europe with my old friends, Podarcis. As that’s gearing up though I’ll be analyzing the data I’ve collected this last Fall, trying to keep on top of all of these breeding lizards, oh, and heading to a deserted island only accessible by helicopter to get baseline data on three endangered, endemic lizard species in partnership with the government of Antigua and Barbuda. Hope that’s enough of a teaser to keep you tuned for more!

And some high-speed videos

Posted on May 27, 2016 by colindonihue

Yesterday’s post was a bit of teaser for the setup of the high-speed video. Now let’s see a couple of examples! (For full effect, I’d recommend playing this on full volume in the background. Rest assured, once we have a highlight reel of lizard runs we’ll definitely be creating a montage of our own)

There’s all sorts of cool stuff going on in this video I had never seen before. For example, notice as the fellow is running into the frame at full tilt he does a little hop and lands with all four feet planted and comes to an almost immediate halt. He then looks left to right to survey his surroundings, and as my big scary hand approaches, turns, pushes off with forelimbs and then generates speed with some big back-leg strides that cause his back to twist with the momentum. He navigates the corners cleanly, but slowly, pausing to look around the corner. Remember though, all of this happens within the span of about a second and a half in real-time.

Now look at this enthusiastic fellow:

He comes barreling in and can’t stop to notice the impending wall. His first crash just turns his head but he sure doesn’t look like he’s attempting to negotiate the turn. At the second crash he crumples and decides a different tact might be best; perhaps climbing the wall and getting out (though it looks more like he’s tap dancing). Again, all of this is happening faster than the eye can really register but at 500 frames per second we’re given a new perspective on these two very different runs.

So now comes the analysis, and this is going to be tricky. Menelia recorded 885 videos and each averages about 2.5 seconds in length. At 500 frames per second that works out to some 1.1 million frames of video to process… Know any good books on tape?

High-speed Sprint Speed

Posted on May 26, 2016 by colindonihue

I’ve posted in the past about the lizard sprint speed studies I’ve tried over the years on erhardii. Each of those experiments have come with the caveat that without a high-speed camera (shooting around 500 frames per second and costing the down-payment for a house) we can’t detect more subtle differences between lizard populations. Well, this year Menelia brought a beautiful high-speed camera from her home institution in Antwerp and we had fun finally getting a good look at these lizards on the run.

First steps, warm up the lizards. We used individual socks this year – a major innovation that made it a lot easier to be sure each lizard did their trial run before the next, and sped the process up without having to chase the lizard around the bin.

Then the white dots. These dots show up nice and clear in the video camera and help track the back of the head, the midpoint between shoulders and hips, and the middle of the back. Hopefully these will make processing the video a lot easier.

Here’s our setup. Note the two rainbow kiddie pools (hard not to notice them). This was a major improvement! The lizards would come rocketing out of the sprint speed track and land on the nice inflated pool floor, ready for us to scoop them up back into their sock.

Notice too that the sprint speed track has a couple of right-angle turns in it. One of Menelia’s questions deals with maneuverability and so we were anxious to see how well the lizards negotiated both the first, and second turns in the course.

Here’s the camera’s eye view. Beautiful! Time to run the lizards.

So what were we up to in the Bahamas?

Posted on November 30, 2015 by colindonihue

Well, the Thanksgiving holidays got the better of me and I didn’t get the next post up as quickly as I was hoping. However, now that cold weather has really settled in in New England, another few photos from warmer climes are a welcome distraction.

As I introduced last post, I just spent a week on the island of North Andros looking for lizards. While the accommodations were cushy, the work was tough and we spent most of the daylight hours (rain or shine) looking for sites and lizards.

A Brown anole, Anoles sagrei, I found on Andros

The research was part of a larger project looking at the widespread Brown Anole, Anolis sagrei. This species is found in a wide range of habitats in the Bahamas ranging from mangroves, “beach scrub” with low bushes and sandy soil, primary coppice, which are remnant patches of closed canopy forest, and secondary coppice, forests in earlier stages of succession.

Mangroves from one of our sites.

Our target was to catch 10 males and females from each of the four habitat types on Andros. Unfortunately, that goal was made trickier by terrible weather:

Driving rain

Our first two days were spent largely jumping out of the car to catch lizards at a new site, only to dive back in as the clouds opened up and dumped rain on us. We did manage to catch quite a few lizards in drizzle, which was a surprise for me given how wimpy my Greek lizards are in bad weather – any hint of rain and they’re running for burrows. Catching the numbers we needed though was almost impossible in bad weather so the first two days were spent largely driving the island looking for good sites with our fingers crossed that one of the days would clear up and give us a good shot at catching our quota.

Lush primary coppice. A beautiful habitat but tough for lizard spotting!

Luckily, on day three we caught our break. We had beautiful sunny weather and hot temperatures that brought the lizards out looking for food. We polished off 3 habitat types in that day alone! It was a long day of catching but felt great to make that progress after the first couple of slower days.

One more look at Mangroves because I didn’t get good pictures of the other habitat types given the raininess.

This project has been covered pretty extensively over on Anole Annals. You can read more posts about it here. Up next are posts about what we were measuring on the lizards and more pictures of the lizards themselves!

Scanning lizards

Posted on June 24, 2014 by colindonihue

A few posts ago I talked about the tough time I was having taking a picture of the undersides of these little lizards. Well, I have a new solution that seems to be working great! Credit goes to Dr. Herrel in Paris.

My printer has a built in flat-bed scanner. Lizard, scanner – put the two together, and voila! Who’d’a thought!

It seems that the best way to keep the lizard still is to place a white paper over the top of the lizard and to lightly press down with your hand. Don’t slam down the clamshell top! Using the “sleeping” trick we’ve even been getting decent pictures of lizard backs too!

The technique came a little late for the bulk of this year’s lizards, but all of my introduction lizards were nicely scanned. I’ve a feeling I’ll be doing a lot of lizard scanning next year to get a better handle on these color morphs!

Here’s a look at what a scanned lizard looks like: Maybe not the most “natural” of poses, but the data’s great – consistent light source, identical photo conditions. This technique is totally going to work!

Colin Donihue

Ecology, Evolution, Nature Photography, and Travel Stories

Tag Archives: Research