Wednesday, October 19, 2011

New Addition to the TNACI team!

I have recently come on board the TNACI staff as the Conservation Associate and I am excited about all of the opportunities that this position comes with! Lee Friedlander formerly held this position and has moved on to teach at a local highschool. I am a native of middle Tennessee (Livingston) and graduated from Tennessee Tech in Cookeville with a bachelors in biology. For the past seven years I have been an Aquarist at the Tennessee Aquarium where my expertise has developed in Syngnathids (seahorses and their relatives), freshwater stingrays and also in native southeastern freshwater fishes, the latter being a reason this position was so attractive to me. I am also working on finishing my Masters degree at the University of Tennessee at Chattanooga where I am researching the population genetics of Hemitremia flammea (Flame Chubs) which are native to Tennessee, Georgia and Alabama. With this genetics experience I am excited to partner with Dr. Anna George on various conservation genetics projects and seek out new projects that will benefit southeastern fish populations as well as captive populations of rare fishes in zoos and aquariums. We live in such an amazing place, surrounded by beautiful scenery, flowing waters and immense aquatic biodiversity. I can't think of a better place to study freshwater fishes and, more than that, to be active in conservation efforts to protect those species and their habitats! Watch out for future postings about new adventures at TNACI as I get settled into this position and seek out conservation research opportunities.

Fall in the Spring

It's fall... which means time for a little spring work. This past week was our annual habitat and fish monitoring at Colvard Spring in north Georgia with our awesome friends at the Conasauga River Alliance, Georgia Department of Natural Resources, and the Nature Conservancy. And since the weather stayed warm, we also got to work on our underwater photography skills! Here are a few pictures from our trip:

Coldwater darters (Etheostoma ditrema) are shy, but seem be responding well to changes in vegetation type and abundance. 

In our fish sampling yesterday, we caught 464 darters--more than we've seen in Colvard Spring before!

Silt is still thick in some parts of the spring...

but is replaced by slightly coarser particles where spring upwellings blow the fine silt away...

 or around the bases of some of the clumps of vegetation (here, a Ludwigia sp.). A mix of stonerollers (Campostoma oligolepis), creek chubs (Semotilus atromaculatus), and orangeside dace (Rhinichthys obtusus) are milling about in the foreground.

One notable change this fall has been an increase in filamentous algae; here it's growing on muskgrass (Chara), sticks, and exposed rock. The floating clumps at the surface are algal mats that have floated free and are decaying.

The algae can look almost otherworldly... The small fish near the surface are western mosquitofish (Gambusia affinis), which are the most abundant fish species in the spring.

A happy TNACI team at the end of a long field day.  If you'd like to see more pictures from our field work at Colvard, check out our Facebook photo album!

Sunday, October 16, 2011

Snakehead Sampling

Wow, it's been a while since we've posted.  We've got a lot to catch up on, so we'll start with a post about our adventures with one of the more famous invasive species, the northern snakehead (Channa argus).  These fish are a popular food fish in their native range of eastern Asia.  Though we hate to villify a species, these fish can seem pretty nasty outside of their home range.  Snakeheads have plenty of teeth, can breathe air through an accessory lung and persist out of water for up to four days, and are very aggressive about guarding their nests from other predators.  So understandably, a lot of people are concerned about their introduction and the impacts they might have on native fishes.

At the end of September, we dashed over to Arkansas to collect snakeheads for a few exhibits.  They've been introduced into two counties in central Arkansas, and we spent a lot of time seining muddy-bottomed agricultural ditches like these:

While the collecting was hard work (and the mosquitoes ate well!), we did manage to find a nice scaly toothy critter for our new exhibit on invasive species for the Aquarium.
It wasn't all scales, though.  We found a nice little green tree frog (Hyla cinerea) at one of our collecting sites who wasn't too unhappy to pose for photos.
Stop by the Aquarium in December to check out our new invasive species exhibit!