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Successfully Hatched Southern Brook Trout!

This is very exciting:

The only trout native to the eastern inland US, the Southern Appalachian Brook Trout was severely threatened for many years, and has only been successfully raised in captivity before by one Hatchery in the world. That the Tennessee Aquarium has done so a closed circulation propagation could be a huge advancement of SABT rehabilitation and reintroduction. 

Baby fishies, I'll drink to that. :)

Wondering though, Gonzan, about whatever threatened them in the first place. Has that been fixed? Are they safe to go out and play?

Second the motion.

Was it caused by overfishing or dam building? Or will they have to stay in their aquarium forever?

I'm not sure what you're asking, Peter, but I'll guess and give a stab at answering :) 

Prior to the advent of the undustrial era and massive loggin operations that nearly stripped the entire Appalachians of trees, The Southern Appalachian Brook trout was the primary predator fish in streams above 2000ft. By the mid 20th century, the Brook Trout had been reduced to a minuscule fraction of it's original range, only 3% of the streams it once inhabited. 

Their range was taken over both by native species such as Smallmouth Bass and Rock bass, as well as Brown and Rainbow Trout, which are not indigenous, but were inroduces in the same century or before. 

Stream rehabilitation and reintroduction has been successful in many places, However, those efforts have been limited by the fact that hatchery propagation of the regionally and genetically isolated species of Brook trout has been almost entirely unsuccessful. The only existing hatchery that has been able to at all is the Tellico Hatchery, also located in Tennessee on the headwaters of the Tellico River. They have a captured flow system, meaning water is diverted from the adjacent river and streams into the artificial rearing runs and pools, and is then directed back to the river.  This system has limitation, including the high season fluctuation in water temperature, ranging from 32-72F.  

Closed circulation propagation allows for much grater control of the environmental variable to optimize hatch yields and growth before release in the wild. The only catch is that with the SABT, it never works, until now. If they are able to continue their success and expand operation, we could see the jewel like fish back in most of these mountain's streams! 

Fascinating, Gonzan. Now I understand why you're so interested. There are so few victories for endangered species nowadays. 

So habitat loss was the primary factor? 3% sounds like there wouldn't be a lot of room for error. Will new releases allow them to re-establish their territories? It sounds like that's the hope. 


That's cool Gonzan, thanks for the link! It's been a long time since I was in the TN Aquarium.


I recently read a good article concerning this from the North Chickamauga Creek conservancy. 

In many areas like the Cumberland Plateau drainages, coal mining is also to blame for the population decline of native Brook trout as well as several other species like insects & amphibians.

Acid mine drainage, which still occurs today from abandoned coal mines, poisons the waters downstream and makes them uninhabitable for many sensitive species.

I also heard on a Public Radio radio program that Brook trout are todays 'Canary' in the coalmine. If the water quality is compromised Brook trout are often the first aquatic species to fail.




It's interesting that the brook trout is having those issues in the east, and is considered the canary in the coal mine.  Here in the Sierra, they easily outcompete native trout (rainbow and golden) in the high elevation lakes.  Many of the high lakes (above 10,000') are overpopulated with brookies.

I think part of that difference has to do with the the genetic and physiological differences between the common and western Brook trout and the SABT. Also, there are far more high elevation lakes and streams in the western rockies, with a large portion of those not having been logged. Here in the east, all but the very highest spires are wooded, and all were logged in the nineteenth and twentieth centuries.  Where you find them still corroborates that hypothesis, as they are the streams at higher elevations- especially those in places that saw less disturbance from logging and mining. 

It is interesting to not that the common Brook Trout can be much more easily propagated in captivity, and seems able to live in a wider range of water types and temperatures. 

Technically, in areas that I frequent (Sequoia/Kings Canyon NP), the high elevation lakes have no native trout.  The SEKI high country was heavily glaciated during the pleistocene, and when those glaciers receded (I wonder whose fault that was 10,000 years ago) there were impassable waterfall/rapids barriers that prevented fish from repopulating virtually all bodies of water above 9,000'.  

The reason those high lakes have fish now is due to the effort of many people in the past 150 years who would carry loads of fish on mules to every body of water that they could reach.  Now the park service is killing the fish in some of those lakes so that the threatened frogs have a chance.  It seems that the trout like to eat the frogs and the pollywogs, and the frog population has plummeted.

SEKI fishing regulations reflect an effort to preserve native trout where they existed before the planting effort began.  Below 9,000' all native species (such as rainbow and golden trout) are catch and release, and only barbless hooks and lures can by used.  Non-native species like brook and brown trout can be kept.  Above 9,000' you can keep anything you catch, and use whatever lures and hooks you want.

The brook trout thrive in the high lakes.  In SEKI, the high country saw no logging and very limited mining.

During a family vacation to Great Smoky Mountains N.P. a ranger program told us that acid rain has been a factor in trout reduction. The water levels in the streams are much more acidic than they were a few decades ago.

go brookies! here's wishing them success.

I find in troubling that the ranger said they are more acidic than "a few decades ago," as that isn't true. Problems with acid rain peaked back in the 80's, having grown in severity for several decades prior to that. The 90's and 2000's have seen significant and continued reduction in acidic precipitation, due to reductions in coal reliance and vastly improved emissions systems. 

Yes, acidic precipitation has been a large problem, but one that has been and is being addressed, resulting in ongoing improvement and far better conditions than a few decades ago.  

This goes along with the falsehoods that water quality of streams and rivers in the US are ever in decline, and that we are loosing our forests in North America. Looking at the big picture, both are blatantly false: There are more trees and forested land in North America now than there have been since even just a few decades ago, and many times what there was at the turn of the twentieth century. Are there streams and rivers that are being polluted and need serious restoration? Yes, but there are countless ones that have been rehabilitated, and many more that are being given the attention and protection they need. 

It deeply bother's me when incorrect information is used to incite fear and fallacy. The truth is serious enough, as improved and expanded conservation practices are needed in so many ways and areas. 

My father is in his late 60s, and whenever I get riled up about some environmental issue, he reminds me that the very fact that we know it's an issue is progress. "We didn't know any better back then. Now we do. So that's an improvement right there."

lambertiana said:

It's interesting that the brook trout is having those issues in the east, and is considered the canary in the coal mine.  Here in the Sierra, they easily outcompete native trout (rainbow and golden) in the high elevation lakes.  Many of the high lakes (above 10,000') are overpopulated with brookies.

 Yes that's very interesting.

I would be willing to bet that water temp may be a large factor in that.

Part of the reason the brookie has a hard time in the southeast (definitely south of the Blue Ridge Escarpment)  is that the summertime water temps rise to a borderline level for the brookie.

Rainbows, and especially browns, can tolerate warmer water better than our native Brook trout. In the streams I have fished all three species tend to hold in deep shaded water during the warmer months. Locally, these deep spots in streams are often called "Blue Holes".

The higher lakes in the Sierras don't ice out until early July in normal snow years, and often start freezing over again in late October/early November.  Those lakes are always cold.  If brookies like cold water, they're in heaven in the high lakes.

On the subject of how things are environmentally today vs prior decades, those of us who remember how things were in the 70s (or earlier) can attest to the fact that there has been a significant improvement.  Things aren't perfect, but we have come a long way.  It's not all gloom and doom as some would have us believe when they try to scare us into giving them more money and power over our lives.

that's it right there - money and control. it's the same crowd that are propagating the global warming fallacy.  

September 28, 2020
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