January 20, 2017
By Karl Weixlmann
Removing a dam on the Catt is (possibly) a good idea
First there were the alewives, plankton-feeding pelagic baitfish that migrated into the Great Lakes through the construction of canals, and were first observed in Lake Ontario in 1873. The largest freshwater inland ocean in the world later became a soup from industrial phosphate discharges over the next century, creating massive plankton blooms that resulted in alewife population explosions. In response, we stocked Pacific salmon to control the alewives. Sea lampreys migrated into the Great Lakes the same way, circumventing Niagara Falls via the Welland Canal, and they sucked the lifeblood out of native lake trout stocks.
Zebra mussels came by ship, and after they took hold, their filter feeding eliminated the plankton, causing the alewife population to crash, and the $7 billion annual Pacific salmon sport fishery to falter. From the ballasts of international ships came the next invaders, round gobies. This domino effect of invasive species altering both the food chain and the habitat has resulted in dramatic ecosystem swings in the Great Lakes, and uncertain challenges to fisheries managers trying to balance them. We're not here to condemn these efforts and institutions, yet man's alteration of the natural environment has consequences we can never predict or control. And yes, our beloved steelhead too, can also be viewed as an invasive fish species.
Cattaraugus Creek on the south shore of Lake Erie is one of the most productive steelhead tributaries in the Great Lakes region and it's only going to get better—or so hopes the Erie County Chamber of Commerce and the New York State Department of Environmental Conservation, along with the thousands of anglers who flock to Steelhead Alley on a seasonal basis to get their fix of chrome. Cattaraugus Creek (aka "The Big Kitty" or just the Catt), has the potential to become the best wild steelhead fishery on the East Coast.
When you first drive over the tributary on Interstate 90 and look down, it would be hard to determine that potential, but upstream from the Seneca Nation of Indians Reservation, the Cattaraugus watershed becomes one of the most ecologically diverse areas in Western New York State.
There has been a lot of talk, speculation, and discussion among steelheaders about the removal or reconstruction of the Springville Dam, also known as the Scoby Dam, that was originally built as a hydroelectric project in 1922, but hasn't generated electricity since 1998. This would allow steelhead to migrate into upper Cattaraugus Creek and its tributaries past the Wyoming County line in New York State. It would also give steelhead access to approximately 70 more miles of fishable stream.
Natural reproduction of steelhead on Cattaraugus Creek that has previously been estimated at around 25 percent of the total river population would increase exponentially. More than 34 miles of public fishing easements already exist above the dam where wild, naturally reproducing populations of trout already exist. These were the first trout that I ever caught with fly-fishing tackle. In March of 2006, 73 percent of respondents to a survey at the Hamburg Sportsman Show said they favored steelhead passage above the dam, yet there are many other factors to consider.
Upstream from the dam are 17 miles of main stem and 27 miles of tributaries that currently sustain a resident, wild population of brown and rainbow trout. Native brook trout also inhabit the headwaters of 15 tributaries. In 1978, one of those wild 20-inch browns came out of a logjam to follow my nightcrawler. Although I never did catch that trout, the Cattaraugus and that trout in the tributary, Clear Creek near Arcade New York, were important chapters in my development as an angler.
Department of Natural Resources (DNR) studies on the Pere Marquette River in Michigan have shown that competition with steelhead has had a negative impact on resident brown trout populations. In 1998, a study showed that the habitat used by steelhead parr and juvenile brown trout was the same, and that they had the same dietary needs. "Differences in the abundance of brown trout over 8 inches . . . lead researchers to conclude that competition with steelhead adversely affected the abundance of resident brown trout."
At the Hunt Creek Fisheries Research Station in Michigan, studies showed negative results after steelhead introductions. In data collected between 1995-1997 and 1998-2005, survival of yearling wild brown trout populations declined by 23% to 36%, while the size of age 2- and 3-year-old trout increased, perhaps due to increased numbers of young steelhead that were now available as a forage species for fewer surviving brown trout.
It is possible that the spawning areas of high-quality gravel in the upper Catt will be taken over by steelhead, because some of these fall-running steelhead spawn at the same time as wild brown trout.
During the spawn, the much larger steelhead dig redds in the most desirable locations, and large male steelhead dominate these locations.
The 2005 study at Hunt Creek said that "there was likely some mortality to brown trout eggs or sac fry by steelhead redd superimposition."
But there are conflicting reports from the Grand River in Ontario, where data has shown that since 1994, with 2 to 3 times more steelhead present, brown trout numbers have not declined.
With an increase in biomass from Lake Erie that would include steelhead eggs and immature steelhead, it's possible that wild trout in the Catt could get much larger, but the trout of my youth could also disappear or be displaced by steelhead. And the days of walking and fishing a lonely stream will become a memory of the past if steelhead are present.
Cattaraugus Creek has the largest spawning population of sea lampreys on the south shore of Lake Erie, costing the Great Lakes Fisheries Commission about $200,000 for every three-year cycle of lampricide treatments. These treatments apparently do not affect steelhead because lampricide sinks into the stream substrates to kill lamprey larvae.
Total removal of the dam would allow lampreys to more than double their spawning area, causing further damage to steelhead and lake trout in Lake Erie, and result in more of those nasty-looking oval sores and scars on the sides of fish we've seen increase in the last decade.
But an explosion in the lamprey population isn't supposed to happen because the NYSDEC and the U.S. Army Corps of Engineers have designed and approved a fish passageway and dam reconstruction that allows steelhead to migrate into the upper Cattaraugus, but keeps lampreys out. A detailed project report from the U.S. Army Corps of Engineers Buffalo District in 2014 showed that "Analysis of the proposed project is not a major federal action which would result in significant adverse impacts on the quality of the human or natural environment."
In August of 2015 the "Springville Dam Ecosystem and Restoration Project" was approved by both the NYSDEC and the Corps with the goal of opening up 70 miles of high-quality spawning habitat to steelhead while continuing to block migration of invasive species like the sea lamprey. This allows the study team to move forward in the engineering and design phase of the project, with construction scheduled to begin in the summer of 2018 if funding is secured. Plans include lowering the spillway height to approximately 13 feet along the current 338-foot length, which will continue serving as a lamprey barrier. The project also includes construction of what is called a rock, riffle, ramp, to act as a fish ladder.
To prevent lampreys from reaching the prime habitat upstream, Geoff Hintz, Buffalo Division Project Manager for the USACE said, "The ramp would have a stop-log barrier with a jump pool and a fish trap at the upstream end. The stop-log barrier would remain in place during the lamprey migratory season and divert fish into a trap for sorting. Outside of the lamprey migratory season, the stop-log would be removed and all fish species allowed to move upstream." Seasonal trapping and sorting is to be conducted by the U.S. Fish and Wildlife Service.
Lampreys spawn during the months of April, May, and June, when trapping and sorting of fish is to be conducted.
"With this project we are protecting and improving our environmental heritage in the Cattaraugus Creek watershed, enhancing the ecosystem for native fish by opening up miles of new spawning areas, but preventing the spread of invasive and destructive sea lampreys," explained Mark Poloncarz of Erie County. Perhaps Poloncarz does not realize that steelhead are not a native fish species in any of the Great Lakes, and that native species like the brook trout may now be threatened.
To quote the NYSDEC Bureau of Fisheries Review of the project, "Biological changes in the fishery are more difficult to predict but development of a naturally reproducing steelhead population in the upper Cattaraugus Creek system would likely cause some reduction in abundance of resident rainbow and brown trout." It also went on to say that, "Increased use of the resource in spring may lead to conflicts among anglers as well as declines in the "quality" of angling for those preferring a more secluded or isolated angling experience."
It would be satisfying to revisit my old fishing haunts I enjoyed as a youngster, and have the possibility of catching steelhead on the same streams I used to wet wade in tennis shoes during summer months, flicking dry flies upstream and hoping for a rise from a wild rainbow or brown. This project could make the Cattaraugus one of the premier destinations in the entire Great Lakes region for hooking wild, naturally reproduced steelhead, and could set a precedent for dam alteration or removal on all Great Lakes tributaries. The possibilities are exciting to say the least, but should also be tempered by the fact that nature has its own way of doing things, and that our best-laid plans have not always gone so well.
Karl Weixlmann is a guide and the author of Great Lakes Steelhead, Salmon & Trout: Essential Techniques for Fly Fishing the Tributaries (Stackpole Books, 2009).