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Conservation Fisheries, Inc. Newsletter #8 August-September, 2001 |
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Boulder Darters Doing Well in Elk River Habitat Enhancement Goal of Recent Project |
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Boulder Darter, Etheostoma wapiti
Placing rocks for habitat enhancement in Elk River near Fayetteville, TN
Tagged Boulder Darter babies being released in Elk River
Bulldozer frees our dump truck from the mud at Elk River site
Volunteers provided assistance with boulder darter recovery work at Elk River site.
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In August, we participated in a
monumental effort to supplement spawning habitat for the
endangered boulder darter, Etheostoma wapiti
(photo at left) in the Elk River. Boulder darters spawn
under the cover of slab-rocks, wedging their eggs in
crevices formed where two rocks lie on top of one
another, or where rocks lie on top of bedrock. The Elk River, in south-central Tennessee and northern Alabama, is the only place in the world that boulder darters are found! The river is characterized by long pools separated by shallow gravel shoals. The pools are heavily silted, covering many of the potential spawning rocks. The shoals have few rocks necessary for spawning. Two years ago, we participated in a similar effort aimed at improving spawning habitat for boulder darters. Several tons of slab-rocks were put into the river at the Interstate 65 bridge. Subsequent surveys by CFI revealed a significant increase in numbers of boulder darters at this site, and most were using the newly placed rock. This prompted the U. S. Fish and Wildlife Service (USFWS) to repeat the process at two additional sites this year. For additional info, see: USFWS Southeast Region News Release The first site was at Fayetteville, TN. This site was known to have boulder darters in the mid 1980s, but the fish seems to have disappeared in recent years. This is the most upstream site in the Elk River where boulder darters were known to occur. Last year, approximately 150 boulder darters (captively propagated by CFI) were tagged and released at this site. A month later, we snorkel-surveyed the site and found four of our tagged darters. They seemed to have settled in nicely in their new home, however, spawning habitat was still somewhat limited. On August 13th, approximately 20 tons of rocks were put out at this site. Complicating this effort was the fact that it had rained·..quite a bit! The river was high and muddy! The gravel bar that normally borders the river at this locality was almost completely submerged. This meant that rock had to be carried out into the river, using a "fire-line" of workers to hand carry each rock! Not only could we not see where the rocks were going, but it was quite an effort for the folks in the deep end of the line to keep from being swept away! But, by the end of a couple of hours, the pile was reduced to some loose rubble and we all headed back to the motel to recover! Before leaving, we released around 200 more tagged boulder darters. These were tagged differently from the ones released last year so we could differentiate these when monitoring. The next day, we headed to the second site at a place called Hamilton Mill. This site was more difficult to access and was very muddy from all of the rain. The large dump truck carrying the approximately 20 tons of rock bogged down a little shy of the river! It was quite a feat (involving a large dozer!) to get the truck free and the rock dumped. In addition to the "fire-line" of folks, several Tennessee Wildlife Resources Agency (TWRA) boats were employed to help place the rocks. The river was still high and muddy, making the work more difficult. We also released nearly 200 tagged boulder darters at this site. These had been spawned by CFI and eventually transferred to the Chattahoochee National Fish Hatchery for rearing. Two weeks after this operation, we returned to survey for darters and see if the rocks ended up where they could be used by the darters. When we returned, the water level was down, but visibility was pretty poor. The good news was that the rock was placed pretty well! Most were situated where they could be used by the fish and relatively easily surveyed by us. We were only able to snorkel the shallow areas because of the poor visibility. Still, we found three of the tagged fish using the newly placed rock at the Fayetteville site! We also went to the Hamilton Mill site. The rocks looked good, but visibility was even worse. We didn't locate any of our fish here. In fact, because of the poor conditions, we saw very few fish at all! Maybe next year! This work was orchestrated primarily by the USFWS office in Cookeville, TN, along with help from the TWRA. But, there were participants from many different agencies and organizations as well as individuals that volunteered their time to help. The long-term effects of these efforts won't be known for years, but we hope that eventually we will begin to see an increase in numbers of this extremely rare darter in the Elk River. We plan to continue monitoring and population augmentation with captively propagated fishes. Ultimately, we hope to be able to stock boulder darters back into Shoal Creek in Alabama. This is an historic site and in recent years, water quality seems to have improved. CFI surveyed in Shoal Creek a few years ago and found good looking habitat that should support boulder darters in several sections of the stream. |
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