Monday, July 6, 2015

On the Amazon and Tapajós rivers


Me and James with our former advisor's favorite fish.

In June of this year graduate student Bill Ludt and I went down to Brazil to attend the Evolution meetings and to do a little fieldwork. The Evolution meetings were in Guarajá but we decided to fly up to Santarém (about 6 hours north of Guarajá) to join the lab of Dr. James Albert from the University of Louisiana Lafayette. James and I both were PhD students in the lab of noted ichthyologist Dr. Bill Fink at the University of Michigan Museum of Zoology (UMMZ) but we didn’t overlap as students (he was there a little over 10 years before me). We actually met for the first time in Brazil in 2004 when I was a graduate student attending the Joint Meeting of Ichthyologists and Herpetologists in Manaus. He was one of the first people I contacted when I found out I would be coming down to work at LSU. We are good friends and he is one of my favorite colleagues. We recently obtained a grant of nearly $800,000 from the National Science Foundation to work on the systematics of fishes from the Neotropics. We were in Santarém to collect fishes from two beautiful rivers that come together there: the clear waters of the Tapajós, and the brown silt and nutrient filled waters of the Amazon. This is a strange mixing of rivers and the fauna is odd here too, you can find sponges, sea gulls, terns, shrimp, and other organisms you would normally associate with being marine. However, the fish fauna is pure Amazonian and completely dominated by a group called the Ostariophysans. These are your catfishes, characins (things like tetras and piranhas) and electric knifefishes (Gymnotiformes), the latter being the group in which Dr. Albert is the world’s foremost expert; he recently had a paper in Science about the genome of the electric eel (which is not an eel at all, but a gymnotiform). There are also many cichlids down here – together there are more than 5000 species of freshwater fishes in the Amazon – about 1/3 of the world’s total! The catfishes alone are quite amazing – the old saying goes “any old fool knows a catfish” but you’ve never seen them like this before. There are nearly 1000 species down here and they include things like the candirú – the notorious parasite of other catfishes that on occasion has been known to swim up the urethra (yep) or anus of unsuspecting bathers. (We have some on display in the LSU MNS Fish exhibit.) There are actually many species of candirú including some freeliving forms and others that are scavengers. One of the species we collected is best known for being discovered inside human cadavers from some unfortunate souls who lost their lives in the Amazon River.
A species of candirú
            When Bill and I arrived in Santarém, Dr. Albert’s lab was just getting into the hotel from a three-day long boat trip. They looked disgusting and I was really jealous: they were muddy, smelly, and all had big smiles on their faces. The Albert lab had struck out the first two days but hit the jackpot on the last day (the day I saw them). They cleaned up and we headed out to get some caipirinhas to celebrate. Santarém is a sleepy river city that besides being the meeting point of the Tapajós and Amazon rivers is also notable for being next to Henry Ford’s abandoned utopian suburbia, Fordlandia. He created an American style village there for rubber plantation fieldworkers under his imagined idyllic conditions – good English schooling, no drinking, and no women – obviously it didn’t last.
The next morning we first headed out to the local fish market. This was a rather large market with four rows of stalls with fish ranging from small anchovies to giant pirarucu (the bonytongue, arapaima). This was in a large outdoor stall and one of the vendors was even able to call in the famous pink river dolphins with a few fish treats. (There is an old Brazilian myth about how these dolphins don hats at night and hit on the women.) We purchased some of the more notable species and headed out to the water. We walked on to a little chartered boat, “The Calypso,” so named because the captain of the boat was obsessed with this kind of music and about a tenth of the boat was filled by a giant set of speakers and a strobe-light disco ball. James got a great deal on the boat and it fit their trawling net they brought from Lafayette. The captain was also quite knowledgeable about fishing in the area. Besides Bill and I, there was James and four of his students, plus the captain and two helpful staff. It may sound like a lot for a 30ft boat but it was rather comfy. We set up a large trawl net at the back end of the boat and sometimes we would take a smaller boat to set out a long (almost 100ft gill net). The captain always picked me to go out and pull in these gill nets. I felt like the kid in the classroom that the teacher always pushed to test their limits. But I soon realized he picked me because I was the only one who could cast net so he wanted me to cast while we waited for the fish to hit the gillnet. We had a successful first day and Bill and I had a fun time interacting with the Albert lab and the staff on the boat. We headed back to the hotel that night and James and one of his students left the next day for some pre-meeting organizing in São Paulo. (James ran a Parametric Biogeography session for the Evolution Meetings.) It was just me and the students on the boat for the next few days and it was a great time. We teased each other giving each other nicknames – Jack from Los Angeles who showered twice a day was “Hollywood,” Max was YCE because he was a “young Clint Eastwood” – and the rest of the pseudonyms I’ll keep a secret between the fishing crew of the Calypso. Besides the teasing we had a lot of amazing samples come in: piranhas, arowanas, cichlids and of course lots of catfish, knifefish, and tetras.
            The first night we strung up our hammocks and were rudely awakened to a violent storm surge. The winds knocked our hammocks together and the Captain and crew were calm but clearly concerned, they had to “batten down the hatches” on our little 30ft’er and sailed us into safer waters. Around 5am he started getting phone calls on a regular basis as we learned a larger boat owned by the captain’s friend had sank. A similar swell happened the next day, with lightening and thunder forcing us to take cover again. It was a bit disconcerting knowing that you are a bit of a sitting duck in the middle of the remote Amazon far from any other people. We were surprised by the strength of the storms, luckily neither lasted long and we were able to get along with our business.
     I loved fishing for little small things on our little side boat we were pulling along the Calypso. We collected many of the cichlids and bony tongues this way and some other rare things. One of my favorites times was going out at night with just a dinky flashlight to small patches of reeds, we were often remarkable successful with just a dipnet and a castnet. Often while I was out on the little boat the rest of the group used hook-and-line to pull in a catch. The crew of the boat, particularly “Donnie” our cook, was quite adept at catching large piranha. One of these, the black piranha (Serrasalmus rhombeus) was such a nice specimen with beautiful interlocking teeth that without thinking I tagged it and sank it into formalin; I realized later that Donnie had intended to cook that fish that night. I felt awful but hopefully made up for it by bringing in other fishes for dinner.
    On our last night out we were pleasantly surprised by the captain finally putting on his speakers and setting the volume to 11. Luckily we were in such a remote place that there was no one that could complain about the noise. He even put on his strobe-light disco ball. We brought some caipirinhas and beers to the roof of the boat and watched the stars and the dense forest around us.
After a few days of not showering and getting muddy and smelly we were glad to be brought back on shore in Santarém. I was ecstatic for our adventures and still feel so lucky to get to do this for a living as part of my job at the LSU MNS.
















3 comments: