Tuesday, June 26, 2012

The Importance of Local Seafood

While some of my TNACI colleagues do research in rivers and streams of the southeastern U.S., much of my research is done in restaurants and grocery stores.  As a seafood scientist, I am always interested in what fish and shellfish food service providers offer, where the fish is from, and how it was harvested.  And there is nothing that I enjoy more than sampling the local seafood wherever I go.  This past week I went to Pensacola, Florida.  Not only was I looking forward to eating some local seafood in restaurants, I was also determined to visit a fish market and bring some home with me.

While there, I was reminded how far we have strayed from the concept of eating locally.  Many seafood restaurants’ specials were fish that were not from the Gulf of Mexico, or even from the U.S.  Atlantic Salmon, which is usually farmed in Chile, Norway or Scotland, was the species that I saw on menus most commonly that I couldn’t help but be a little disappointed.  If I had visited northern California or Alaska, I would have been excited at the prospect of eating Pacific Salmon: not in Florida.  Depending on the restaurant, however, there was a plethora of local fish available for me to enjoy, including Triggerfish, Flounder, Yellowtail Snapper, Oysters, and Blue Crab.

Crab stuffed Flounder

Steamed Blue Crab claws
Baked Yellowtail Snapper

At the end of my trip, I was looking forward to bringing some local flavor home with me.  There was one large seafood market that many people recommended I visit.  Upon arrival the sign advertised a “wide selection of fish from the Gulf.”  When I entered, I was quickly disappointed.  Over half of the selection of fish was not even from the U.S.  Seafood from the Gulf of Mexico was limited to Blue Crab, Grouper, Shrimp, Amberjack, and Mahi Mahi.  The rest of the counter was graced with Atlantic Salmon, Pacific Swordfish, Asian Tilapia, Basa (an Asian catfish also known as Swai), among many others.  I left, disheartened.  I drove around until I saw another, much smaller, seafood market, and decided to stop in for a comparison.

I walked in to Maria’s Seafood and was immediately excited about the selection of fish.  Ninety percent of it was from the Gulf of Mexico.  The place smelled clean and fresh and I was excited to get started selecting fish to fill the cooler I had brought with me.  The fishmonger spent 20 minutes with me, helping me select the best fish and the best fillets for me to take home.  This store took great pride in their local fresh seafood and it showed in the care they gave their customers and fish.

Fresh seafood collection: Mullet, Bream, Flounder, and Speckled Sea Trout.

Cutting a Yellowfin Tuna steak from a fish that was caught in the Gulf of Mexico.

Florida seafood species
Me and Rita, my fishmonger.


Why, you may ask, am I so picky about where my seafood is from?  There are several reasons.  The first is the rigorousness of U.S. fisheries management; we are one of the best countries in the world.  Globally, 30% of fisheries are overexploited, whereas in the U.S. only 20% are overexploited.  In addition, being a locavore is much more preferable when it comes to seafood.  Carbon dioxide emissions from transportation are contributing to global climate change.  It’s also a great cultural experience to indulge in local cuisine.  Eating salmon in Florida is like going to China and ordering a Big Mac.  So, the next time you venture to the coast, ask your server what is caught locally, take pride in your country’s seafood, and explore the flavors that are unique to that area. 

Friday, June 22, 2012

Goldline Darters in Alabama

Brett Albanese, Lucas Hix, and Chris Yator from Georgia Department of Natural Resources and Evan Collins of TNACI.
     Last week TNACI biologists Bernie Kuhajda and Evan Collins met Georgia Department of Natural Resources biologists Brett Albanese, Lucas Hix, and Chris Yator on the Cahaba River in Alabama in search of federally threatened Goldline Darters (Percina aurolineata); this species gets its name from the gold line above the black blotches along its side. It is endemic to the Mobile Basin and is restricted to the Cahaba River in central Alabama and the Coosawattee River in northern Georgia. The study is looking for genetic differences between the Alabama and Georgia populations of this very rare fish. A small piece of fin tissue was removed from each specimen that will be used for genetic analysis by professor Steve Powers at Roanoke College in Virginia. The group was able to catch 56 Goldline Darters from 8 localities, most in shallow water flowing over gravel and larger rock (cobble). Forty additional fish species were also collected; the Cahaba River is the most diverse river for its size in the United States, with 130 species of fishes recorded.

Goldline Darters (Percina aurolineata) with the lower specimen showing the gold line above lateral blotches. These six were all collected in one seine haul!

Collecting for Goldline Darters in the Cahaba River at Piper and in Schultz Creek.

Our first site was the Cahaba River in the town of Centreville, where 34 species of fishes were collected, including several Goldline Darters.  This site is very diverse for fishes as it sits on the Fall Line, an area that separates the upland to the north (Valley and Ridge province) with the lowlands the south (Coastal Plain province) and therefore has both upland and lowland fish species. This is the most downstream site for Goldline Darters. Other fishes collected are shown below.

Male Greenbreast (above) and Rock Darters (below) (Etheostoma jordani and E. rupestre) found in shallow fast water with gravel and larger rocks.

Nuptial male Tricolored Shiner (Cyprinella trichroistia) with breeding
tubercles on top of head and snout.

Similar-looking common Mimic Shiner (Notropis volucellus, top) and federally endangered Cahaba Shiner (N. cahabae, bottom); note Cahaba Shiner lacks downward expansion of lateral stripe just before base of tail and darker tail (caudal) spot.

We collected Goldline Darters upstream in the Cahaba River proper at four other sites with the most individuals (20) collected near Helena approximately 40 miles upstream from Centreville. We tried to get Goldline Darters from their most upstream site in the Cahaba (another 8 miles upstream from Helena) but were unsuccessful.

Goldline Darters were also found in all tributaries where they are known from, including Schultz and Shades creeks and the Little Cahaba River. The largest population is in Shades Creek (13 specimens collected), which was just discovered in 2006 along with federally endangered Cahaba Shiners (Notropis cahabae). Before this discovery Shades Creek had been considered polluted and only a few tolerant fish species were known from upstream localities.

Updates on the results of the genetics study will be posted when available!

We caught this Alabama Map Turtle making a nest and laying eggs. Very cool!

Shades Creek site was just discovered in 2006 to have Goldline Darters as well as Cahaba Shiners!

Monday, June 18, 2012

Fish Biology at Mountain Lake Biological Station

This summer, I’m spending a few weeks out of Chattanooga and in the woods!  I’m co-teaching a course on the Biology and Conservation of Fishes at the Mountain Lake Biological Station (MLBS).  MLBS was founded in 1929 by the University of Virginia and is located in southwestern Virginia, about 30 minutes outside of Blacksburg.  Biological field stations are really important places for research and education.  Most stations offer summer courses like ours, and they also provide space for students and scientists to study natural processes, often in remote settings.
Lewis Hall, the main teaching and research building at MLBS. 
MLBS sits on ~650 acres on top of the 3800 foot Salt Pond Mountain, right on the Eastern Continental Divide.  We’re surrounded by 100,000 acres of the Jefferson National Forest in addition to private land managed and protected by the Mountain Lake Conservancy.  It’s a great place to study ichthyology, because some of our mountain streams drain to the Gulf of Mexico through the New or Tennessee rivers, while other streams drain to the Chesapeake Bay through the James River, or directly to the Atlantic through the Roanoke River.  Each of these different drainages has lots of unique fish species, which means our students have a lot of diversity to study without having to drive very far.
Dr. Dave Neely leading a discussion of fish diversity in the New River drainage. 
Snorkeling in the South Fork Roanoke River.  I'm impressed at how long some students stayed in without wetsuits!
Classes at a field station are an incredible experience because they’re so immersive.  Almost every waking moment can be devoted to biology.  During the day, we’ll have lectures, small group work, lab, or my favorite, field time.  We’ve hiked from the station about 1500 feet down the mountain until we reached an elevation where the streams held native brook trout; a small waterfall keeps them from getting father upstream.  We’ve conducted field labs where our students have used different methods to learn how to estimate the population size of certain fish species in a stream.  In the evenings, we’ll gather for seminars from other researchers or just work in the lab to help students learn how to identify fish.  And we often get totally absorbed in our work, which is why we’re grateful to hear the dining hall bell ring to remind us it’s time to eat… though we still often talk about biology through every meal.

It's not just about fish--we saw this mink next to the South Fork Roanoke River.
Salamander diversity is also high in this corner of the woods.  This is a red eft, the juvenile stage of the Eastern Newt.
On a personal note, this has been a really special experience for me because the two classes I took at MLBS when I was an undergrad (groan, fifteen years ago!) really fostered my interest in learning more about Appalachian animals.  Field experiences like these are defining moments for most biologists, where we move out of the lecture hall and into our “real world.”  What puts the icing on the cake for a field biologist is the support of a community that understands, and even celebrates, the time we spend wandering through the woods with a notebook and a question.  
Studying their field guides by a covered bridge on Sinking Creek.

Thursday, June 14, 2012

Intern Update: Feeding, Cleaning, and Sampling

Intern update
Well we have been making our summer husbandry interns work hard the last few weeks! May 23rd we took a road trip down to Warm Springs National Fish Hatchery to pick up 2,000 juvenile sturgeon, which is their primary job this summer. We have research and conservation projects that need field work this summer as well so there is plenty to do.  It takes everyone to keep TNACI going! 

Stephen Floyd is our full-time intern this summer. Stephen comes to us from Virginia where he just graduated from Roanoke College. He has a passion for southeastern fish and is especially intrigued by Southern Appalachian Brook Trout so he is working on an independent study of this species this summer.
Stephen cleaning sturgeon trough.

Jessica holding her first sturgeon
Jessica Hubbuch is graduate student at the University of Tennessee here in Chattanooga and is working with us as a part-time intern this summer. She is currently working on some urban stream surveys with UTC and organizes their museum of biological specimens. She is working hard this summer to help TNACI organize, label and find homes for many cool specimens that we have been saving over the years from the Aquarium. Scientists are always on the lookout for preserved specimens to use as teaching tools believe it or not!
Louise McCallie and Josh Oliver are also working with TNACI this summer. They are both volunteering their time to help us a few days each week. Louise is a 2011 graduate of GPS here in Chattanooga and just finished her freshman year at Lehigh University so we are glad to have her while she is home for the summer. Josh is finishing up his biology degree at Dalton State and is helping us out one day each week to get some fisheries experience.

Whew what a crew! We are lucky to have so much good help this summer. These guys are excited to be here and ready to work hard and learn lots!

Most of the intern work has focused on caring for our lake sturgeon babies so far.  When sturgeon are so little (many of them were 1.5 cm on May 23rd!), they need to be fed often. The first few weeks we fed four times each day so someone had to be at work at 7am and someone had to stay each evening until 8:30. Now that they are so much bigger (up to 8.5 cm!) we have reduced that to three times per day. Regardless, each time we feed there is cleaning to do. The fish eat for an hour or two with the pumps turned off and the water calm to make it easier for them to “hunt”.  If the food sits on the bottom too long it begins to degrade, which can make the water unhealthy for the small fish, so the tanks are cleaned shortly after the fish eat.  It’s a daily cycle of feeding and cleaning... much like a human baby!

We also have to sort and measure fish so all of the individuals in each tank are approximately the same size.  This minimizes competition for food. Each week we take a series of measurements on a sub-sample of fish to keep up with how fast they are growing so that we can adjust feeding amounts and make other changes as needed. At first, all 2,000 fish were in one trough tank. Currently they have been sorted into 4 tanks and as they continue to grow they will be divided into 6 troughs. This extra space helps the fish to grow but it also increases the amount of work it takes to keep everything clean. Did I mention we clean a lot?

Measuring sturgeon
Our interns also get the chance to go in the field and help with some of our conservation projects.  Last week we went to the Conasauga River to do some surveys for Conasauga Logperch (Percina jenkinsi).  Everyone paddled kayaks down the river and snorkeled in a part of the river that we had not surveyed before.  We were assessing the habitat along this stretch of river and of course, looking for our target species. Unfortunately we didn’t find any Conasauga Logperch, but there was still a lot of aquatic wildlife to be seen so we took pictures of holiday darters, tadpoles, Mobile Logperch, turtles and insects. It was a long day but worth the effort.
Evan and Louise on the Conasauga River

River Cooter
Holiday Darter 
Musk Turtle

Later this summer we will be working at the Colvard Springs restoration site and collecting fish for the Aquarium and ongoing research projects. Stay tuned to hear more about all the work we are doing this summer at TNACI while we have all this great help!