SPECIAL REPORT: Sturgeon X-rays Reveal Ingested Fishing Tackle

2013-09-27T20:55:00Z SPECIAL REPORT: Sturgeon X-rays Reveal Ingested Fishing TackleBy Virginia Hutchins vhutchins@magicvalley.com Twin Falls Times-News

RIGGINS • Three sturgeon handlers stood back as Tony Lamansky wiggled wires and clicked an X-ray trigger.

Their laboratory was the floor of a jet boat, leaving the dock at Pittsburg Landing to roar up a sturgeon-filled stretch of the Snake River inside Hells Canyon. So standing out of the X-ray zone wasn’t easy.

Lamansky, a senior fishery research biologist for the Idaho Department of Fish and Game, leads an innovative research project: recording images of the ingested fishhooks, weights and swivels inside the massive bodies of live sturgeon.

Anglers and state biologists have seen hooks emerging from the sidewalls of sturgeon and line trailing from their vents — the remnants of sportsmen’s fishing trips.

White sturgeon can live for more than 100 years, and Idaho’s fishing is catch-and-release only. So how long does ingested metal remain inside a sturgeon? Can it be assimilated or excreted? And does the metal affect fish mortality at a level that harms population numbers?

Lamansky aims to find out.

His equipment is novel and unprecedented: a mobile X-ray machine manufactured for equine veterinarians but adapted for on-boat use with Lamansky’s custom rack. The $80,000 setup includes a generator, a computer to record X-ray images and heavy-duty cases for everything.

• • •

Even $80,000 can’t guarantee easy science.

On the morning of July 24, as the sun climbed above the high rim of Hells Canyon toward a day of three-digit heat, the X-ray generator wasn’t firing. Lamansky knew which tiny connection was to blame.

“But it’s not like we can just run into RadioShack,” he said.

Some muttering about a “10-cent plug” was audible from Lamansky’s direction, and his head dropped over his knees.

“I think he’s praying right now,” said Liz Mamer, a fisheries research data coordinator for Fish and Game.

The laboratory vibrated and jumped as boat driver Tim Stuart avoided rocks and angled through rapids. He slowed to pass the pontoon and inflatable rafts of an overnight rafting party camped on the riverbank, and the idling jet boat of a pair of anglers.

Stuart docked at Kirby Creek Lodge. He and his Idaho Power Co. colleagues sleep at the rustic, generator-powered bed and breakfast — where the only driveway is a dock — while working their three-day shifts of sturgeon research on this stretch of river.

Lamansky and Mamer disappeared into a shop behind the lodge. On board, Idaho Power fisheries technicians Chad Reininger and Doug Kenyon opened a bucket of pickled squid, its smell a sharp, acrid slap.

Reininger pierced strips of pickled squid on big circle hooks, curling each strip to pierce it again. Kenyon chopped fresh smallmouth bass, caught from the Snake. They’d alternate the two baits on set lines that day.

On shore, Lamansky sat at the lodge’s long dining table, splicing the wires of a phone cord whose connector he’d already ground to fit a narrower slot. His tools: Gorilla Tape and a Leatherman.

“Ingenuity is occurring,” Mamer said, wiping sweat from Lamansky’s nose for a photograph. “Kirby came through for us.”

Back on board, Lamansky still ground and fiddled. But Stuart could wait no longer.

“We’ve got to get moving to those fish,” he said.

• • •

Some of the wild sturgeon waiting on those researchers’ set lines couldn’t pass quietly through a metal detector.

In late 2010, Fish and Game biologists conducting a separate sturgeon study — on deep-hooking rates for different hook types — borrowed a portable X-ray machine to begin exploring what happens to ingested metal.

In Hagerman in September 2011, Lamansky inserted tubes into 120 hatchery sturgeon to place hooks in their stomachs. X-ray images spaced three months apart show some hooks eventually corroding, then breaking apart.

“They’re not going anywhere fast,” Lamansky said.

Fish and Game pays a Hagerman businessman a monthly fee to rent those fish, which swim in raceways along the river.

In 2011, Lamansky took over leadership of Fish and Game’s X-ray study, with on-boat equipment funded partly by Idaho Power, and intensified the survey of wild sturgeon in the Snake River.

By the end of 2012, he said, the project had 10 recaptures from Hells Canyon, identified by tiny, implanted tags as fish already caught and X-rayed once. Of the 10, one rid itself of all metal; a previously clean sturgeon ingested tackle; and images of the remaining eight fish showed metal both times — some old, some new.

“So they are able to process metal to some extent, but then they eat more of it,” Lamansky said, while driving from his Nampa office to meet Mamer and the Idaho Power team on the river.

Researchers learned quickly that the main metal source isn’t anglers’ lines breaking after sturgeon are hooked. Rather, lines catch and break on the river bottom, then sturgeon vacuum up the bait, the hooks, the lines and whatever tackle is attached.

The evidence? Some of the metal gear on the X-ray images is for catching steelhead, bass or crappie, and only a tiny percentage of the hundreds of X-rayed river sturgeon had been deeply hooked.

Could fishery management changes grow out of this research? Good question, Lamansky said, but too soon for answers.

In addition to Hells Canyon, Lamansky’s team has X-rayed Snake River sturgeon below Shoshone Falls, below Bliss Dam, and between Swan Falls Dam and C.J. Strike Dam since 2011.

But the project’s hot spot is Hells Canyon, coinciding with Idaho Power’s once-a-decade survey of the white sturgeon population there.

Catching huge fish and lifting them safely on board in a water-filled sling is no easy matter. It makes sense to add Fish and Game’s X-rays to the measuring, weighing and tagging of fish caught by Idaho Power’s set lines.

It’s mercilessly hot work.

• • •

Tanned and often silent, Reininger, Kenyon and Stuart handle the heavy chains, the forceps, the squid buckets and the 28-foot twin-motor Bentz of this operation with the smooth cooperation of a practiced team.

But why does an electrical utility employ fishery technicians and a jet boat driver?

The Federal Energy Regulatory Commission requires Idaho Power to monitor white sturgeon populations as part of the mitigation for its hydroelectric dams on the Snake River.

Hells Canyon’s sturgeon are a “core conversation” population — wild and self-sustaining from natural production — but scientists don’t have good long-term trend data there.

“Earlier studies relied on using various sampling strategies, so our surveys now use consistent sampling methods to begin establishing a long-term, standardized monitoring program in the Snake River,” Idaho Power spokesman Brad Bowlin wrote in a project brief.

In Idaho Power’s current three-year survey, scheduled for completion by the end of 2014, field crews sample sturgeon each week from June to October on a scheduled progression through 140 miles of the Snake and 23 miles of the lower Salmon River, Bowlin said.

This is no casual fishing.

During each three-day excursion, a crew sets 14 lines, checks them twice a day, records data from captured sturgeon and returns them to the river. The utility shares its data — fish abundance, sizes, condition factors, growth rates — with Fish and Game, the Nez Perce tribe and Oregon and Washington agencies.

Hydropower, agriculture and flood control have divided the river into “smaller subsets that, in many cases, can no longer provide all the habitats necessary for sturgeon to complete their life cycles,” Bowlin’s brief said.

These broadcast spawners deposit their eggs in fast-flowing currents. After hatching, the larvae disperse on those currents.

“Once these conditions are lessened or removed ... the early part of the life cycle appears to break down,” Bowlin wrote. “Sections of river that are still of sufficient length with a full complement of habitat, and have significant river flow in the spring during spawning periods, are areas where sturgeon can still maintain populations.”

Those fish draw recreational anglers who relish the pursuit of Idaho’s ancient monsters.

• • •

On the morning of July 24, Stuart maneuvered the jet boat into place beside buoy No. 1 on the rocky riverbank.

Kenyon hopped onto the edge of the boat, then quickly stepped around its small canopy, onto the bow, and onto the rocks. Hand over hand, he hauled up the heavy chain attached to the buoy, then a 100-foot rope and its six circle hooks — designed to catch sturgeon by their outer lips — then another heavy chain that weighted the set line.

In the 11-mile stretch of Hells Canyon scheduled for this team on July 23-25, most of the 14 set lines were in locations randomly generated by a computer. Two were in sturgeon-rich spots that Stuart chose.

All 14 were in the shadeless inferno.

“Any chocolate you have, eat it right now,” Stuart said, dipping his cap in the river.

Kenyon stood on the bow holding the set line while rafts and kayaks floated by and Lamansky labored over his X-ray cables. Some connection was still loose, or some wires mismatched inside his makeshift splice.

“OK, let’s go to work then,” Stuart said quietly.

Lamansky acknowledged his defeat with mild swearing.

“Let’s go to work,” Stuart said more loudly.

But the crew waited for Lamansky and Mamer to stow the X-ray machine and computer in protective cases.

• • •

The first two sturgeon off the set line were small, and they shared the sling. Two poles long enough to rest on both sides of the boat supported the sling, and a pump supplied a continuous flow of river water over the fish. Water drained from holes in the sling, splashing onto the floor of the boat.

With a small knife, Kenyon cut off a sturgeon’s second left scute — a visual cue during future catches that this fish has been handled before.

After a pass with a PIT tag detector, Reininger confirmed: “It’s not a recap.“

Kenyon called out measurements to Stuart, who manned the clipboard from the driver’s seat. Stuart recorded the identification number of a new PIT tag — a passive inductive transponder — while Reininger worked the tag into the fish, just below the dorsal fin.

The pair working at the sling clipped a DNA tissue sample from the anal fin and passed the forceps forward to Stuart, who filed the tissue in a box of ethanol-filled vials. They passed a metal detector over the fish, hung it briefly by the tail from a hand-held scale, and lowered it back into the water.

Its small companion, already missing the second left scute, carried a PIT tag whose type and number indicated a catch recent enough that the team didn’t need a new genetic sample. Holding the tag reader, Mamer read the lengthy number aloud so Stuart could check his transcription.

Within minutes, all of the columns on Stuart’s clipboard were filled in, and that fish, too, swam away.

• • •

But the next sturgeon to appear as Kenyon raised the set line was a big one. So he and Reininger lowered the sling into the river and heaved the fish in. When this sturgeon flipped inside the sling, it splashed everyone on the boat.

“It’s another recap, Tim,” Reininger called to the driver.

It took both technicians to measure the fish as water poured onto their tape reel on the bottom of the boat. Total length: 208 centimeters. From the snout to the fork in the tail: 185 cm.

Later, researchers would use those lengths, along with pectoral girth and pelvic girth, in a formula to indicate the fish’s condition.

Sturgeon have no visual external differences to indicate sex. That requires surgery.

Reininger smeared iodine to clean a small spot on the fish’s side, cut a slit of less than an inch in the body wall and peered inside with an otoscope — the same instrument a doctor uses to examine a human ear.

Inside the sturgeon, Reininger saw small eggs starting to develop. An immature female.

“That’s an F1,” he told Stuart.

With catgut, Reininger made two stitches and a sturdy knot, then another pair of stitches to finish closing the incision. Next to his surgery site, a scar suggested a similarly tidy job with the same four stitches.

“We don’t have a good grasp on aging sturgeon yet, but this fish could be potentially 50 years or older,” Reininger said, pulling a dose of antibiotic from a bottle into a syringe.

As he and Kenyon hooked the scale to the sling and tipped out the water, Mamer offered a quick wager on the sturgeon’s weight. Her guess: 125 pounds. Lamansky’s: 120 pounds.

He won. After 16 pounds were deducted for the sling’s weight, the answer was 109.

• • •

Farther upstream, at the second buoy, the day’s fifth sturgeon was 149 cm long.

“Just under surgery size by a centimeter,” Reininger said.

Still, this fish was long enough that Lamansky and Mamer would have X-rayed it if they could. And the metal detector’s beeps confirmed those images would have been interesting.

Lamansky’s glum posture at the front of the boat was eloquent on the subject of lost data.

On this line, Stuart’s chart indicated a switch from fresh bass to pickled squid that morning, and the oppressive smell of squid returned as the technicians fastened a new set of baited hooks to the set line.

Kenyon jumped from the bow to the bank to set the buoy in the rocks.

“Don’t forget about snakes, man,” Stuart said.

Inside this boat’s canopy, a couple of snakes’ rattles are pinned to the fabric with a fishhook.

• • •

Already well behind schedule that morning, the crew encountered another new problem at set line No. 4.

“I think this PIT tag reader’s too hot,” Reininger said. “Not turning off.”

The technicians held the reader in front of the small fan blowing on Stuart’s face, then decided on more serious therapy: icing the tag reader in their drinks cooler.

While they waited, Mamer divided their rations of cold salmon and steak, eating her steak with her fingers. Caddis flies dotted the boat’s windows.

“If we don’t have PIT tag data, it’s not even worth doing it,” Reininger said.

He pulled the tag reader out of the cooler to plug it into the charger.

“It’s not getting juice,” he said. “I bet this thing’s fried.”

Mamer leaned over the sturgeon in the sling to shade its belly, and Stuart looked through the instructions for the power inverter.

• • •

The tag reader recovered in time for the crew to gather data on that fish. Set lines 5, 6 and 7 turned up empty; they’re in computer-generated locations, so Stuart wasn’t surprised.

“Fish on!” Stuart cried at line No. 8.

But this hooked sturgeon took off in the water. Reininger immediately dropped the set line, and the chain clanged as heavy links slipped off the bow. Buoys remain attached in case of moments like that one.

When they got that sturgeon into the sling, the technicians found fishing line trailing from its vent — another X-ray subject wasted.

“Don’t pull too far,” Lamansky said as Kenyon took a blade to the line. “There’s probably a hook on the other end that’s digging into who knows what.”

The PIT tag reader acted up again and took another chilling in the cooler. Kenyon kept water flowing onto the fish in the sling and splashed its gills whenever they rose out of the water.

This time, when Reininger plugged the reader into the charger, it blinked right into power-save mode. And Stuart suggested the possibility of a “rail dump” — releasing anything hooked on the set lines without collecting data.

“Well, let’s dump this fish out,” Reininger said. “PIT tag reader goes down, this whole project pretty much goes down.”

The crew needed new orders. After a few tries, Stuart reached an Idaho Power biologist by satellite phone.

But the tag reader was back in business. It would just have to be iced after each use.

Despite several more empty lines, it was 3 p.m. when the crew finished work normally done by 11 a.m. After delivering journalists back to the dock at Pittsburg Landing, they’d face the day’s second round of 14 set lines under Hells Canyon’s relentless sun.

Smelly, hot and hungry, with no handy support for problem solving: That’s science on the river.

Disclosure: Writer Virginia Hutchins’ husband is employed by Idaho Power Co., in a division unrelated to dam operation or mitigation.

Copyright 2015 Twin Falls Times-News. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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