UNH Researchers Help Restore Fish Population

Inside a small marine lab in Newcastle Doctor Elizabeth Fairchild with UNH’s Zoology Department shows off a fish tank that holds four flounder - two females and two males.
“Over here in our smaller tanks, these are three foot diameter tanks that have black plastic screening on them to create nice ambience for them these are our honeymoon tanks, which are set up for brood stock to spawn in.”

These four captive fish are the first step in raising juveniles that will eventually be released back into the ocean.
1187 1:48 “They’re actually quite cooperative; we just need to be patient”

But it takes quite an effort to raise a flounder in a hatchery that will survive in the wild.
Wild flounder change color to camouflage from predators and burrow in the sand.
Hatchery flounder have to be trained to do that.
“If we release a fish that’s just straight out of our tank, it may take two days for it to really bury itself, the whole time it’s pretty visible to a predator that it may be the wrong color it may be more like our rearing tanks which are blue or green rather than the dark sand that’s underneath the water”

Fairchild says in the past they kept the potato chip size baby flounder in cages in the ocean before releasing them completely, giving them time to adjust to their new environment.
But these cages attracted an invasive and voracious species called the green crab.
“what we found is that the cages are acting like a snack cage for the crabs, the crabs aren’t getting into them but they’re attracted to the cages containing fish, so it’s like we’re ringing the dinner bell for the green crabs, they’re coming in and they’re just waiting until we open up the cages and let the fish go.”

This time, Fairchild and her team of researchers have a different strategy..
(Nat sound 1191 )
They’re loading more than one-thousand slightly bigger year-old fish onto a tank on the back of a truck.
These juvenile flounder have already lived in tanks with sand in them, so they’ve honed their burrowing skills.
Their destination: the Hampton Seabrook Estuary.
1212 (Nat sound ocean)
(1200 once you get a couple of buckets of fish, head on down the beach)
UNH research scientist Nate Reynolds is helping Fairchild release the juvenile flounder bucket by bucket… this time in the early spring, when there aren’t as many green crabs around.
(1199 1:38 you certainly don’t want to throw them out like their a bucket of chum or something you just sort of place of them, put the bucket halfway in and pull the bucket from underneath them, and they just sort of float away and in theory they all head to the bottom)

The flat fish, now about the size of a piece of bread, swim quickly to the bottom and delve into the sand.
Fairchild observes like a proud mom.
1210 :27 I do feel like we’re letting them go but I’m very excited, maybe it’s kind of like seeing your kids off to college you’re happy to have them go, but you still worry about them, you know you’ve done a good job preparing them, but you’re still going to wonder if they’re okay all along

But Fairchild and fellow researchers will be able track the movements of the fish to get an idea of their survival.
They’ve all been tagged with a special latex dye underneath their skin – it shows up as a small red line that’s visible with a black light as they grow older.
Fairchild says commercial fishermen in the Gulf of Maine used to catch 18-thousand metric tons of the fish a year in the 1980’s – those numbers are now down to just 500 metric tons.
She hopes researchers will eventually be able to release tens of thousands of flounder back into the wild – but it’s a process that could take more than a decade.
For NHPR news, I’m Amy Quinton.