Tom Remington recently wrote a blog entry on sterile fish and their potential to grow faster and perform better than fertile hatchery fish, which allocate a portion of their growth potential toward reproduction.  The topic is a very interesting one, especially since sterile hatchery fish do not threaten wild populations with the potential for interbreeding and compromising genetic integrity.

Many state fish and wildlife agencies will tell you that they do not stock fish with the intent of seeing them reproduce.  The vast majority of stocking programs are either put-and-take, or put-grow-and-take, where fish are stocked with the intention of becoming part of an angler’s bag limit.  Furthermore, most waters are stocked because they cannot provide a fishery through natural reproduction.  Most agencies use regulations as a first resort to protect a fishery.  If natural reproduction simply can not keep up with angling pressure regardless of regulations, a stocking program is usually implemented.  This lack in natural reproduction is often due to lack of spawning habitat, but can result from other causes as well.

The bottom line is this: if most fish are stocked without the intent of reproducing, what drawbacks are there to a sterile fish that has the potential to grow faster?  I don’t see many.  Convincing the public that it’s a good idea to stock sterile fish might be a tough sell, simply because most people still don’t quite understand why a department would stock fish without expecting them to reproduce.

One of the greatest benefits to a stocking sterile fish, in my opinion, is the ability to stock these fish in waters that contain native fish that might otherwise be threatened with interbreeding or hybridization.  This means that states can stock wild trout waters with hatchery trout, knowing that they are not compromising the genetics of wild fish. 

Granted, you can’t just go willy nilly stocking on top of native fish everywhere you go.  There are issues in some areas where hatchery fish could potentially outcompete wild fish.  There are some areas where stocking is not necessary and might hinder a wild fishery in recovery.  Also, the method of sterilization, while significantly developed in some areas, is not yet foolproof.

The Idaho Department of Fish and Game has been working on producing sterile triploid hatchery fish for years, and to date, every rainbow trout stocked in the state of Idaho is sterile.  Therefore, the department has the freedom to stock in areas where they might otherwise have to worry about hatchery rainbows interbreeding with wild rainbows and hybridizing cutthroat trout populations. 

Sterilization of hatchery fish is an advancement led by state fish and wildlife agencies primarily in the West.  Idaho Fish and Game fisheries biologist Joe Kozfkay and others completed a survey of state fish and wildlife agencies throughout the U.S., and found that 10 other states have current sterilization programs, and most are in the West.  Only 2 states with fish sterilization programs lie east of the Mississippi River.

While there are some hurdles to overcome, primarily the logistics of developing a sterilization program and having state agency and public support, I believe that the future is promising and many developments lie ahead.  Because of the ever-increasing concern over the protection of native and wild fish, it is imperative that state agencies at least consider the development of a sterilization program.  Aside from it likely being mandated in the future, such a program would vastly increase the options that state fish and wildlife agencies have in relation to where they stock fish.

Portland General Electric has begun the removal of 47 foot tall Marmot Dam on the Sandy River, which boasts sea-run populations of steelhead trout, chinook and coho salmon, all protected under the Endangered Species Act.  Nearby Little Sandy Dam is slated for removal next summer.  Environmentalists and anglers alike hope that the removal will result in increasing runs of salmon and trout, and I for one am anxious to see what the future brings for these fish in free-flowing waters.  Dams are attributed as the major cause for declines in most anadromous fish populations, and it will be intriguing to evaluate their effectiveness in an era of ever-increasing dam removals.

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Ever hear of a sicklefin redhorse?  Neither have I, until now!  It appears that this fish, recently discovered by scientists, was once a staple food item for Cherokee Indians in the southeastern U.S.  Officials report that the redhorse, which can grow up to 3 feet long and to weights exceeding 7 pounds, is found in only two river basins.  Current research is being conducted by scientists at North Carolina State University studying the movement patterns and reproductive biology of the redhorse, and a Virginia professor is reportedly still in the process of formally describing the fish.  

With help from the federal government, the Cherokee tribe is in the process of introducing the fish into new waters in hopes that they will successfully reproduce.  No word yet on political issues involved with the redhorse, but stay tuned.  This one’s under the radar for now, but the rare fish will likely be another target of political conflict sometime in the future.  It has been proposed as an endangered species by the U.S. Fish and Wildlife Service.

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Scientists Study Sicklefin

Meet the Sicklefin

A recent electrofishing survey completed by the Vermont Fish and Wildlife Department shows that stream habitat improvements in Vermont’s Batten Kill River appear to be the cause of increased fish numbers.  The project was funded by Orvis, the Green Mountain National Forest, and the National Fish and Wildlife Foundation.  The project provided increased shelter and foraging areas for trout in a river that lacks such habitat due to development that has removed shoreline structure.  Such habitat projects are common, and usually appear to be successful, but most go unmonitored.  Hopefully Vermont Fish and Wildlife continues to monitor this project to determine if similar stream improvement provide benefits equal to or greater than their cost. 

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Scientists report research findings stating that fish process different information on different sides of the brain, drawing comparisons to the human mind.

Check out the article here

For over 5 years now, a heated debate has dragged on between environmentalists and state and federal agencies over the status of Yellowstone cutthroat trout.  Environmentalist groups petitioned for the listing of the Yellowstone cutthroat under the Endangered Species Act in 2001, but the U.S. Fish and Wildlife Service, after an extensive review, declared the listing unwarranted.  The decision was challenged in court in 2005, and resulted in a similar outcome. 

Despite the scare tactics and legal challenges brought on by a number of camps, the biological data still show that this subspecies of cutthroat continues to persist, and is in no immediate danger of extinction by any means.  In fact, the most recent study led by the USFWS, in cooperation with three state agencies, shows that Yellowstone cutthroat populations continue to persist, with no evidence supporting the claims of challenging groups that the subspecies is experiencing drastic declines.

Instead of trying to better understand these populations and how we can help them recover to historic levels, many groups simply rely on false information, with a ’sky is falling’ type of attitude.  And why wouldn’t they?  It’s the most effective way to raise money, increase funding, and support their cause, which oftentimes conflicts with traditional uses of fish and wildlife, primarily hunting and fishing. 

What makes things worse, is that all the money the USFWS spends (our tax dollars, mind you) conducting reviews and fighting off court challenges, is money that could be used to fund species conservation.  While Yellowstone cutthroat trout are not endangered by any means, conservation efforts are probably necessary for their long term persistence.  Despite this, one might argue that many environmental groups are doing more harm than good for the species they intend to save, by channeling the focus toward legal battles instead of real, on the ground conservation activities. 

We should applaud state agencies that work to protect and enhance native sport fish populations despite lack of funding and countless legal challenges.  In the end, they, along with concerned citizens and sportspersons are, in my opinion, the real key to species conservation.  

Driving by part of Montana’s Big Hole River recently, I commented to my girlfriend that it was surprising not to see anyone out fishing in what looked like great trout water.  Being no stranger to Montana, she noted that the state’s Department of Fish, Wildlife and Parks closes many rivers when the water temperatures get too high.  Such closures are a new concept to me, so I decided to check it out.

Just this month, several of Montana’s major trout fishing destinations were closed by the FWP due to warming water temperatures.  According to protocol, whenever one of the major trout rivers in the state reaches or exceeds 73 degrees F for three straight days, closures are imposed.  Most of the rivers are closed from 2 pm to midnight, but some 24 hour closures exist.

The reasoning behind the fishing closures is that as the water warms and begins to approach their upper critical threshold for survival, trout become increasingly more stressed.  Add to this the stress of being caught by anglers, and fishing mortality becomes much higher.  When a fish is caught and released, it needs access to cool, oxygenated water to fully recover.  Warmer water holds less oxygen, and therefore makes it harder for captured fish to survive the ordeal.

The closures oftentimes last the entire summer, depending on stream temperature.  See a list of recent fishing closures in Montana here. 

As part of some side work for the University, I snorkeled Big Creek in northern Utah this weekend.  Big Creek is home to a population of native Bonneville cutthroat trout, which has declined due to a combination of stocking nonnative brook trout and brown trout, and habitat degradation in some areas. 

My snorkeling surveys were part of an evaluation of a stream improvement project completed by the BLM years ago.  The BLM created an exclosure that kept cattle from reaching the stream for a stretch, and constructed pools and riffles to create more diverse fish habitat. 

I snorkeled a site lower in the creek that was apparently overgrazed by cattle, which was evident by the lack of vegetation cover and undercut banks, incredibly high sediment loading, and high water temperature, near the lethal limit for trout.  I observed a number of suckers in this reach, but not a single trout.

The restoration site contained six different fish species: cutthroat trout, brown trout, brook trout, sculpin, shiner and sucker.  It was exciting to see how well trout could do in the same general area, with better habitat conditions to work under.

I snorkeled a third reach, just above the stream improvement site, which was only lightly grazed by cattle and contained even more fish.  I think the combination of better physical habitat and cooler water temperature were key in determining trout abundance and distrubution.

Another pattern I noticed was that while cutthroat numbers were the same in the two upper reaches, brook trout numbers increased significantly in the uppermost site.  This was likely a combination of the slower, meandering channel, undercut banks and pools, and colder water temperature in this reach.

Seeing those trout while snorkeling got me so excited that I decided to do some fishing after I was done.  I went above the upper reach and started casting elk hair caddis and orange grasshopper patterns in the creek.  The constant meandering S-curves in the stream made it fun to fish, and you could cover a lot of water without walking very far.  Also, there were no trees present to mess up my casts! 

I hooked into some nice Bonneville cutthroats, a mess of brook trout (which were welcomed by this native Mainer), and a nice looking brown.  Took some brookies and the brown home for dinner and sent the cutty’s back in the drink.  Made for a great weekend combo of snorkeling and fishing, and I’ll be sure to return and explore this creek even more.     

Uncle Mike is a coworker who’s a little older, more experienced in life, and a fly fishing fanatic.  I don’t know a single person who fishes more, on a consistent basis, than Uncle Mike.  He was the only person out fishing the Logan River every day in the dead of winter, with bruises on his thumbs from picking ice off his rod guides.  So an opportunity to learn some of the techniques he’s picked up was something I looked forward to. 

We took off to a nearby fishing destination after work on Friday and proceeded to fish until it was pitch black out.  We started off fishing a deep run in the stream, with the incredibly cold water making my feet ache till they were numb.  The cold water was shooting fast out the bottom of an upstream reservoir, keeping it in perfect condition for trout fishing even in mid summer.  It was much higher than usual, and a bit difficult to fish, or so I thought. 

We decided to fish one at a time, switching after each hooked fish.  Mike started, and with surprise, I saw him throw his fly up against the shoreline bushes with relative ease, and not a single false cast.  That was the first thing he told me,

“You’re false casting way too much, and all it’s doing is scaring the fish.”

Mike switched over to a hopper imitation he’d tied up, and proceeded to hook into a huge brown trout.  We measured it at 16 1/2 inches in the net, which didn’t do this old, thick fish much justice.  It had the head of a 20+ inch trout. 

It was my turn.  And with nary a false cast, I began throwing the big rubber hopper imitation, kersplashing it on the water’s surface for added appeal.

“A hopper doesn’t just gently land on the water surface” said Uncle Mike, ”you need to make it sound real.  The trout can hear that kersplat”. 

He was right.  I got the hopper right at the edge of an undercut bank and ripped out a 15 incher.  We moved up to the next pool, where we each caught another big brown. 

Then, it was on to a long, slow, shallow run, a place where I never would have expected a fish to even exist.  Mike worked the undercut bank with overhanging vegetation with no luck.  However, he continued to work areas in the stream channel that I routinely ignore. 

“You gotta hit all the water“, he continued to repeat.

Then the real surprise came.  He landed the hopper in a four inch pocket of water, and BAM!!!…….pulled out a 13 inch trout!

I smiled in disbelief, and then took my turn casting into the run.  I hit all the good water, and then, just to keep Mike off my back, I cast into the same 4 inch pocket of water, about 5 feet upstream from where he had pulled out his trout.  BAM!!!!!!!  Another brown!!!  I was beside myself.

We kept it up until we couldn’t see our flies anymore, and ended at a pool just above a beaver dam, where I casted, dead drifted the hopper, and waited to listen for the splash of a rising trout……..and waited……and waited……and waited.  And it came!

SPLASH!!!! 

The evening ended with a nice 13 1/2 inch brown, and memories of Uncle Mike’s highly stressed words of advice:

“Never stop a dead drift!!!“.

It turns out that the tropical fish caught by a man in a North Carolina river a couple weeks ago was actually a Pacu, close relative to the Piranha, but as Carl Strohmeyer notes in his blog, there really isn’t much cause for concern, since the fish would never have survived the winter due to the area’s low water temperatures. 

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