Whale Rescue in the Canal

A little more than a month ago I got an email regarding a fossil find near the construction site of the new canal locks on the Atlantic side of Panama. The photo that came with the email was a bit blurry and with no scale, so it could as well be a small fossil, or even an invertebrate. However, I took the chance as it was, after all, an opportunity to look at outcrops on that part of the canal (most of our work is towards the Pacific side). And so it was, that the spring interns (previously featured here and here) and myself ended up driving towards Colón with the hopes that the fossil was some sort of interesting vertebrate.

One thing I must mention, is that security is very tight in the canal, much more so near the construction sites. So that day, we only had about 20 minutes to look at the fossil and eventually come up with a plan to collect it at some later time, if it was worth it.

And it was! Upon seeing the fossil, I immediately recognized it as a baleen whale jaw. Most of what we could see was a cross section of it (see below), which meant that however long the jaw was, it was going straight into the wall.

Part of a baleen whale jaw, in cross section.

It is not the first time that fossil whales have been found in Panama. A 2010 paper by Mark Uhen of George Mason U. and colleagues (including yours truly) described all that was known of the fossil marine mammals of Panama. Admittedly, it wasn't much, but we were able to confirm the presence of dugongid sirenians, toothed whales (odontocetes) and baleen whales (mysticetes) (Uhen et al., 2010).   Since then, more and better material has been found, including a couple of odontocete skulls that I have helped collect from the late Miocene Chagres Formation (see here and here), as well as other things you'll hear about later this year at SVP.

The new whale mandible was found in the Gatun Formation of late Miocene (12-8 Ma) age (Collins et al., 1996). The Gatun is better known for the abundance of invertebrates (e.g. Woodring, 1957; Hendy, 2013) and for having deposits that represent nursery sites for Carcharocles megalodon (Pimiento et al., 2010). Previous reports of whales from the Gatun include odontocete ribs (Uhen et al., 2010), so finding a baleen whale is a first!

Like I mentioned above, that day we only had a very limited amount of time, and the fossil was worth rescuing. And so it was that over the next month or so I began coordinating with the Panama Canal Authority to go back and collect the fossil. Just last week we were able to go back. This time I had a new group of interns, and over the course of two days we were able to collect the fossil.

The summer interns at the dig site. Chris (at far left) prospects, while Christina and Silvia dig around the whale jaw.  You can see the construction of the new locks in the background.

Unfortunately, due to the nature of the outcrop we only had a limited space and depth to dig. So we had to make the best out of it. Sadly, that meant that if the jaw was longer than our depth limit, we had break it.

The whale jaw, prior to being jacketed.

Me posing with the now jacketed whale jaw fragment. 

The exact affinities of the whale jaw remain a mystery, for now. Hopefully once it is prepared I'll be able to determine what it is. So stay tuned!


References

Collins, L. S., A. G. Coates, W. A. Berggren, M.-P. Aubry, and J. Zhang. 1996. The late Miocene Panama isthmian strait. Geology 24:687-690.

Hendy, A. J. W. 2013. Spatial and stratigraphic variation of marine paleoenvironments in the middle-upper Miocene Gatun Formation, Isthmus of Panama. Palaios 28:210-227.

Pimiento, C., D. J. Ehret, B. J. MacFadden, and G. Hubbell. 2010. Ancient nursery area for the extinct giant shark Megalodon from the Miocene of Panama. PLoS ONE 5(5):e10552.

Uhen, M. D., A. G. Coates, C. A. Jaramillo, C. Montes, C. Pimiento, A. Rincón, N. Strong, and J. Velez-Juarbe. 2010. Marine mammals from the Miocene of Panama. Journal of South American Earth Sciences 30:167-175.

Woodring, W. P. 1957. Geology and paleontology of Canal Zone and adjoining parts of Panama. Geology and description of Tertiary mollusks (gastropods: Trochidae to Turritellidae). U.S. Geological Survey Professional Paper 306-A:1-146.

Return to the Caribbean side of Panama, pt. 2

A couple of Friday's ago, we were set to return to the locality where we had been excavating a relatively large whale skull. Last time we were there we manage to make the jacket around the skull, but the plaster did not dry quickly enough, and we had to leave it, as it was late in the day and the tide was coming in. Unfortunately, due to the change in time of the low tide (happening later and later in the day) as well as other technical problems, we could not go back as soon as we wanted. So we ended up waiting a whole week to return and hopefully finish the job.

A local girl, Pedro, Nicole and Samantha pose next to the jacket.

To our surprise, the jacket held up during the eight days that passed since we made it. Those were good news as it meant that our work and effort from the previous week was not lost and that we didn't had to make a new jacket. Plaster bandages are hard if not impossible to get here in Panama, so I was extremely happy we didn't had to use more than we already had.

Pedro, a local kid, Erik, Nicole and Samantha happily pose next to the large jacket as we get ready to move it to the truck.

We were able to remove the jacket and get it into our truck without further incidents, this wouldn't have been possible without the interns who are doing a great job! To top it off, we even found another tooth associated with the skull. Its not the first one, Aaron had already collected two, which were somewhat incomplete, but hinted at the affinities of the skull. The new tooth we collected is complete, and I can now confidently say that it belongs to a physeterid (a sperm whale)!! Sperm whales are found nowadays in the Caribbean, but their fossil record in the region is relatively poor, with only a handful of reports from a few sites. So this is a fantastic find!

One of the teeth associated with the skull in the jacket. Notice the large root and small enameled crown (to the left of the photo).

Stay tuned, as I'm sure we'll keep finding many other interesting fossils here in Panama.

Return to the Caribbean side of Panama

As part of the PCP-PIRE we not only get to look for fossils and study the geology of Panama along the canal. We also get to prospect and collect at other localities. Yesterday, we made the two hour drive to the Caribbean side of the country, where late Miocene marine units are exposed along the beach. If this sounds familiar, is because I had been there a couple of years ago, where, as part of the Pyenson Lab we went to collect a really nice fossil dolphin skull.

On our way to the locality we had to go through the Gatún Lock, and wait for several ships to go through before we could cross.

Going to this locality means we have to really plan ahead, as the late Miocene deposits will be best exposed at low tides. That also means that we only have about a four hour window to prospect and collect.

As the water recedes, the rock is exposed and its time to prospect!!

Ideally, we can find and collect specimens on a single day (within that 4 hour window), others may take longer, and require to return to the site one or more additional days.

Here Samantha and Pedro work on a project they stated with Aaron several months ago, excavating a large whale skull.

We worked two sites simultaneously this day. Pedro, Samantha and Erik continued an excavation they started several months ago with Aaron. They are digging around what seems to be a large whale skull. Nicole and I were about 15-20 meters southwest of where they were. We were busy digging what seems to be part of yet another whale skull. The skull seems to be broken or at least there's a skull and postcranial elements associated with it, so we collected these in two jackets (see picture below).

Here we take a break and have some snacks and talk with the local kids while the two small plaster jackets (center of the pictures) dry out so we can remove them and take them back to the lab.

We'll go back today to finish off the large whale skull, and who knows what else we'll find. So stay tuned!