Category Archives: science

Tips from the scales — Read between the lines to learn salmon data

Photos by Jenny Neyman, Redoubt Reporter. Fishery biologist Tony Eskelin, with the Alaska Department of Fish and Game office in Soldotna, points out features in an impression of a salmon scale magnified through a microfiche reader. As the head of the Fish and Game’s sampling of kings harvested in the Cook Inlet East-side commercial set-net fishery this summer, he examined over 600 scales like this to gauge the ages of the fish caught.

Photos by Jenny Neyman, Redoubt Reporter. Fishery biologist Tony Eskelin, with the Alaska Department of Fish and Game office in Soldotna, points out features in an impression of a salmon scale magnified through a microfiche reader. As the head of the Fish and Game’s sampling of kings harvested in the Cook Inlet East-side commercial set-net fishery this summer, he examined over 600 scales like this to gauge the ages of the fish caught.

By Jenny Neyman

Redoubt Reporter

If only salmon could talk. Biologists could solve some of the age-old mysteries about these wild, wily creatures, and answer questions regarding Alaska king salmon that have become increasingly worrisome in recent years.

It might go something like this:

How you been? Back so soon? Been getting enough to eat?

In a way, salmon can talk, at least so far as communicating information about themselves. It just takes a trained eye, rather than ear, to “listen.” And a fish scale, rather than mouth, to “speak.”

A single scale can say a lot about a salmon — its age, its growth patterns, its general life history. Similar to how a tree can be aged by counting its rings, calcified structures in fish, such as their scales and otoliths (ear bones), develop tiny rings, called circuli, that correspond to the growth of the animal. “Reading” the patterns of circuli and spaces between them can reveal information about a fish — did it grow a lot when it was out to sea? Did it survive some kind of injury or other limitation on its health? How many years did it spend in the ocean before returning to its natal stream to spawn?

The method for doing so is intricately precise, yet has a bit of a mystical feel, sort of like if biologists set up a tea leaf-reading booth at a science fair.

“Do you see it? Concentrate right in here. You can zoom out if you need to, that helps sometimes. The other trick is to step back and all of a sudden, ‘Oh, I can see the lines,” said Tony Eskelin, fisheries biologist in the Soldotna office of the Alaska Department of Fish and Game. Eskelin headed the sampling project of king salmon harvested in the East-side Cook Inlet commercial set-net fishery this summer, meaning he had the task of aging hundreds of scales this fall. As with most nonintuitive processes, practice makes more proficient.

“I got a lot better after the, oh, 600 I did,” he said. “There are little things you can do to see them better.”

The idea of mining calcified structures for biological information is an old one — scientists first started examining fish scale patterns as a means to identify different groups of fish in the early 1900s. The standard technology used isn’t exactly going to set a Silicone Valley tech conference on fire, either. Sampled scales are affixed concave side up — like a contact lens — to scale cards marked with a grid three tall by 10 wide, accommodating three scales each from 10 fish. The cards are then pressed onto clear acetate sheets to make impressions of the scales, so the patterns can be examined while the scale cards themselves are filed into storage.

Scale cards lined with king salmon scales await pressing to transfer their images into the acetate covering the cards.

Scale cards lined with king salmon scales await pressing to transfer their images into the acetate covering the cards.

The scale press looks like a cross between an industrial drill press and an Easy-Bake Oven. The scale cards are covered with precut acetate sheets and placed on a metal tray, which is fed into a slot between two plates in the press. Pumping a lever brings the plates together, with a dial showing the force of pressure. Another gauge shows the temperature. There’s a specific recipe to be followed.

“It needs to get up to 25,000 PSI for two minutes, at at least 190 degrees,” Eskelin said.

When the cards are pressed they’re removed — hot, use gloves — and examined to make sure the impressions are clear. If not, they’re repressed. If they’re good, the cards are ready to be examined. On to hulking technological relic No. 2 — a microfiche reader, the kind used in libraries to examine film of old newspaper clippings.

salmon scales press

Tony Eskelin loads three scale cads, covered with a layer of acetate, into a scale press at the Fish and Game office in Soldotna. The machine presses and heats the scales, so that an impression is made in the acetate. The acetate then can be examined, while the scales are filed away in storage.

They might not be on the hot list at Best Buy this Christmas, but the machines are still used because they still work great for this task, said Wendy Gist, fisheries biologist in the Soldotna office, whose task this year was aging scales taken from sockeye salmon sampling.

“It’s kind of funny we use these old-fashioned machines. But I’ve done so much research because I’ve wanted to update to keep up with technology, but nothing works like this,” Gist said.

Once the microfiche is loaded, the science the science of scale reading becomes a little more of an art form. The methods of examining scales have been refined and standardized, sometimes minutely enough for one stock of salmon versus another, but there’s definitely an acquired knack to telling one clump of teeny-tiny wiggly lines from another clump of teeny-tiny wiggly lines.

That’s what the examiner looks for — bands of concentric circles radiating out from the focus — the line where the scale was attached to the fish. The distances between the circuli indicate how rapidly a fish has grown. Closer-together lines indicate a period of slower growth, which generally means wintertime, when feeding conditions aren’t as good. That’s a winter check. Bands with farther-apart circuli indicate a period of rapid growth, which generally occurs in the summer.

“You see a summer here, where it’s a little bit wider spaced — that’s better feeding, typically. Different feeding patterns are what create this pattern,” Gist said.

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Sludge sleuthing slows in shutdown — Federal furloughs put breaks on testing unusual algae bloom in Kachemak Bay

Photo courtesy of Marion Beck. A mysterious brown algae bloom has clouded the waters of Kachemak Bay, prompting scientists to wonder if it could raise an environmental concern.

Photo courtesy of Marion Beck. A mysterious brown algae bloom has clouded the waters of Kachemak Bay, prompting scientists to wonder if it could raise an environmental concern.

By Naomi Klouda

Homer Tribune

A brown sludgy plankton bloom slogging into small bays that rim Kachemak Bay is raising concerns of how it may impact the delicate filtration systems of shellfish and other marine life.

The plant life is described as 4 or 5 deep in its most concentrated areas.

It can appear foamy, accounting for the milky surface.

So far, this plankton from the group Gymnodinium is thought to be more of benefit than a harm, but scientists won’t be sure until they can have it analyzed in a NOAA lab in North Carolina. Kris Holdereid, the NOAA manager of the Kasitsna Bay Laboratory near Seldovia, was midstride into an inquiry on the root beer-colored plankton bloom. Then came the U.S. federal government shutdown.

“I am not allowed to work on it, not even to volunteer to keep studying it,” Holdereid said.

The phenomenon was noticed during the routine water monitoring program conducted each summer in the bay. NOAA water monitoring biologist Dominic Hondolero and Holdereid were tracking, collecting samples and placing them under a photo-microscope in order to document it. The photo samples would then be sent to an Outside lab for identification.

“We gathered more samples on (Oct. 7). It turns the water brown, like when we had the red water from the red plankton bloom, only brownish, indicating an abundance of that particular bloom,” Holdereid explained.

Fishermen and oyster farmers had called agencies expressing concern.

Clem Tillion, a 60-year resident at Halibut Cove, said that in all his years, he had never seen such a breakout. But he feels certain it is not a harmful event.

“Algal blooms gives our oysters and waters nutrients. Clear water has no life,” Tillion said. “This isn’t necessarily bad, but it’s more than we’ve normally seen. I’ve never seen this much algae. It’s one of the biggest localized blooms.”

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Centered on salmon — Fish at the forefront of new initiative

Redoubt Reporter file photo

Redoubt Reporter file photo

By Joseph Robertia

Redoubt Reporter

The University of Alaska Fairbanks is soliciting public input from those who care about salmon and want to have a say in their future, as a UAF Center for Salmon and Society is perhaps being created to serve as a science-based effort to help create a more sustainable future for Alaska’s salmon.

On Thursday, a sparsely attended meeting at the Cook Inlet Aquaculture Building produced some positive input toward the center’s creation. But organizers are still hoping to give those interested a chance to offer suggestions, since all too often when a decision regarding salmon management is made, some people find themselves dissatisfied with the decision — either from not understanding the science behind it, not knowing which agency had the final say, or how they, the individual, could have contributed to produce a different outcome.

“My job is to seek feedback from a wide range of people, state agencies, nongovernmental organizations, businesses, Alaska Natives and anyone else who wishes to provide input within the Cook Inlet region (Kenai Peninsula, Anchorage, Mat-Su),” said Hannah Harrison, a private researcher contracted by UAF to conduct the public input process.

Harrison said that she has been conducting long-form interviews with individuals who are active in the fishing communities, as well as hosting public meetings to give anyone interested a chance to give input.

The inception of the idea for a center, which would be housed at the university, is the result of a preliminary proposal put together by a team of scientists working with the UAF School of Fisheries and Ocean Sciences and the Nature Conservancy. One of the primary goals would be to engage people from many walks of life throughout and beyond Alaska about salmon-related issues.

Harrison said that input from Thursday’s meeting, as well as previous one-on-one meetings with locals, has produced good feedback so far.

Some of the themes to come up so far regard the idea that collaboration and partnerships with scientists, managers, fishing and related organizations and key government entities (state, federal, tribal, municipal) is important, she said. And many people have emphasized the importance of the proposed center being independent of interest groups, both in its funding structure and research emphasis.

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Research vessel ties up busy season

Photo by Naomi Klouda, Homer Tribune. Capt. Billy Pepper ending the season on the R/V Tiglax.

Photo by Naomi Klouda, Homer Tribune. Capt. Billy Pepper ending the season on the R/V Tiglax.y Naomi Klouda

By Naomi Klouda

Homer Tribune

The research vessel Tiglax returned to port in Homer on Friday after a four-month season that found birds flourishing since a rat eradication effort at Hawadax Island and inspected for rebuilding vegetation on an island made barren by a volcanic blast.

Capt. Billy Pepper and his crew experienced a busy summer, hauling supplies and hosting 160 scientists and biologists. They traveled 16,400 miles, a distance equal to going back and forth across the U.S. five times.

“We went down the Aleutian Chain and over to Sitka this time, no trips north to the Pribilof Islands this year,” Pepper said. “We had good weather. Everything went pretty well.”

They weren’t greeted by good news on their return, though. Congressional sequestration threatened to shut down the Alaska Maritime National Wildlife Refuge’s work — and any federal employees — until the funding questions are resolved. Refuge Manager Steve Delehanty was preparing Monday for whichever route lay ahead.

If allowed to keep on through a funding resolution, the public will get a glimpse at how research and coordinating are done from the ship in remote Alaska. Saturday from 1 to 4 p.m., the Tiglax is to be open for visitors.

But the event might be canceled in the federal shutdown this week. On Monday, the crew finished taking equipment and supplies off the ship.

“Normally we would have two weeks to get this done. Now we’re doing it all in one day because I don’t know if I’ve got a crew to work tomorrow,” Capt. Pepper said Monday. “I’m not going to unload the ship by myself.”

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Tsunami debris surveys underway

By the Homer Tribune

The Marine Conservation Alliance Foundation released the results of their tsunami debris monitoring program July 3.  Further monitoring efforts are underway but additional funding is necessary to conduct cleanup activities.

Debris suspected to be from the tsunami was reported in Washington State in December 2011. In response, in January 2012, MCAF established a monitoring program to detect the presence of debris on Alaska’s shoreline and to test suspected pieces for radiation.  The program used experienced marine debris cleanup contactors in Sitka, Craig, Yakutat, and Kodiak.

As described in the newly released report, Results of the 2012 MCAF Japanese Tsunami Monitoring Program; buoys, large pieces of Styrofoam and liquid containers used for fuel were found along the shores. Experienced contactors recognized much of this was not typical debris. Near Sitka 1,600 pounds of mostly Styrofoam tsunami debris was identified from eight beaches. Styrofoam was also the biggest problem in Yakutat with 95 blocks and 52 floats identified. This was followed by the large black “oyster floats” (48 identified).

Using hand-held Geiger counters, monitors found no radiation contamination. This is consistent with expectations since the Fukushima meltdown occurred after the water had receded.

The study found that much of the debris is Styrofoam, which greatly concerned Marine Debris Program Coordinator Dave Gaudet. “Just imagine Styrofoam in the storms this winter getting bashed against the rocks. Right now the pieces are big and can be picked up, but next year they’ll be broken to pieces and nearly impossible to remove.”

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Wave energy — Tidal study to map where power may be harnessed

By Naomi Klouda

This map shows the tide sampling stations in Cook Inlet.

Homer Tribune

Imagine a time ahead when tidal power will be as easy to tap as hanging up a solar panel. A time when turning on the lights involves depending on the power of storms rather than crude oil hauled from the depths of the earth.

That possibility might not be too far into the future.

Three partners launched 10 tidal monitoring stations last week from Turnagain Arm in Upper Cook Inlet to Kachemak Bay in Lower Cook Inlet for a viable start to the process. The National Oceanic and Atmospheric Administration Center for Operational Oceanographic Products and Services measures the currents and the Coast Survey Development Laboratory built a hydrodynamic model. The Alaska Energy Authority has the funding.

The project involves collecting readings from the meters over a two-month period, said Kris Holderied, manager of the NOAA Kasitsna Bay Laboratory.

“The current meters will be in place for two months and will be recovered in August,” Holderied said. “The current meter deployments are part of a partnership project between NOAA and the Alaska Energy Authority to quantify the tidal energy potential in Cook Inlet.”

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New views — Climate change, urbanization impact peninsula

By Joseph Robertia

Photo by Clark Fair, Redoubt Reporter. Ice retreats from the surface of Skilak Lake.

Redoubt Reporter

The celebration of Earth Day is a time to think about the planet, the ways it may be changing and what those changes mean to its inhabitants — humans not excluded. Here on the Kenai Peninsula, many transformations are taking place with the flora and fauna, and while sometimes difficult to observe from a ground-eye view, the patterns of change are a bit easier to understand when seen from above.

To illustrate this concept, John Morton, supervisory biologist at the Kenai National Wildlife Refuge, presented “The Kenai Peninsula at 30,000 feet,” as part of Kenai Peninsula College’s Earth Day celebration last week.

“The bottom line is things are changing,” Morton said. “I’m not pointing fingers to the cause or offering up solutions, I just want to put the facts out and show the empirical data to let people know this is real and happening right here.”

Using satellite imagery overlaid with various graphics, Morton was able to show one of the most easily observable changes to occur to the peninsula in the last 100 years — the human population growth and subsequent urban expansion.

Rather than an area with no roads, a scattering of small towns, Native communities and fish camps, the completion of the Sterling Highway in 1951 and the discovery of oil in 1957 brought many changes to the peninsula over the next several decades.

“Just in the last 30 years the human population has increased from 25,282 to 53,578 people,” he said.

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