Statistics from a recent report show that Atlantic salmon catches in Scotland in 2006 were among the highest on record, totaling nearly 86,000 salmon!  Fishery managers believe that the increased catch is indicative of a larger salmon run, resulting from the buyout of commercial fishing interests among other conservation measures.  In addition, more anglers than ever are releasing caught salmon.  Experts still caution that care should be taken to ensure that this encouraging trend continues, and they cite uncertainties in marine survival and escapement of hatchery stocks as management challenges.

Despite the great news for salmon, catches of sea trout (sea-run brown trout) have declined considerably, and are among the lowest on record.

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Following a federal court decision intended at limiting water use to protect California’s delta smelt, four water districts are filing suit against power plants that pump water from the Sacramento-San Joaquin Delta to cool turbines.

The groups cite data indicating that tens of thousands of fish are killed by being sucked up by the pumps, and that outflow from the plants is returned to the delta at a warmer water temperature, degrading delta smelt habitat.  

In addition to suing the power plant company, the groups are planning to file suit against the U.S. Army Corps of Engineers for authorizing the activities.  

Water from the delta is not only important for power generation, but also for the area’s agricultural landscape and residential water use.  One solution to prevent losing delta smelt through the pumps includes installing very expensive fish screens to prevent entrainment.

Read more here  

I haven’t been online lately because of the Utah muzzleloader mule deer season.  The season opened Wednesday, and I saw 6 bucks that morning, one that I should have killed, but I blew it.  Spent all day Wednesday and yesterday hiking in the mountains upwards of 9,300 ft. elevation.  Saw 6 does yesterday, no bucks.  Catching up on work today, then I’ll be back out Saturday and Sunday for another shot.

What a nifty way to raise money for fish……..

The rights to name 10 species of newly discovered Indonesian fish were auctioned off this past week for a total of $2 million.  The money will go to education programs and habitat conservation for the ten species to be named at a later date.  Now if only our fish and wildlife agencies could think of some similarly innovative stragegies to help fund fish conservation and management….

This week I was able to get some pictures of kokanee salmon during their annual spawning run up the tributary to a local lake. 

Kokanee (Oncorhynchus nerka) are the landlocked form of sockeye salmon, kind of similar to landlocked atlantic salmon found in many northeastern U.S. lakes.  Native forms of kokanee are found in many lakes that currently have, or have had runs of sockeye salmon from the Pacific Ocean.  It is believed that these native stocks arose from sockeye salmon offspring that stayed in inland lakes after hatching, instead of returning to the ocean. 

But the kokanee that most people are probably familiar with are those that have been stocked in inland lakes by fish and game departments to provide additional fishing opportunities.  This is the case with the fish I was observing this past week. 

One of the coolest things about these fish is that they take on an amazing red color in preparation for spawning, as opposed to the silvery color they possess prior to spawning.  Their color is such that one can walk along the shoreline of a kokanee spawning river and easily see each spawning fish. 

Unlike Atlantic salmon, species of Pacific salmon are semelparous, which means that they spawn once and die.  We observed thousands of kokanee spawning in the stream, as well as a number of dead carcasses of fish that had expended all of their energy spawning, and died.  There were tons of raccoon tracks and bird tracks on the shoreline, and at one point, there was a place along the shore where a mink had apparently pulled a number of kokanee from the river and eaten their heads, which contain the highest energy content in the fish’s body.

Kokanee are a popular sportfish and play a significant role in cycling nutrients in the ecosystems they inhabit.  They consume zooplankton and fish in the lake environment, spawn in the streams and die, where animals and insects consume them, excrete nutrients, many of which return to the aquatic ecosystem, feeding phytoplankton, which feed zooplankton…..and the cycle continues.  And aside from that, they’re fun to fish for and pretty cool to check out during the spawning run!

Nat Gillespie, fisheries scientist with Trout Unlimited, recently wrote an article on the threat culverts pose on survival of brook trout throughout their native range.  Hundreds of thousands of culverts have the potential to block fish movement because they’re oftentimes poorly placed and alter the natural flow regime of a stream. 

While suitable habitat may exist both above and below a culvert, and many fish populations thrive despite such a barrier, movement plays an important part in the long term persistence of healthy fish populations.  Free movement along the length of a stream system allows fish to recolonize areas where populations may have been reduced or are threatened by human impacts or environmental factors.  Fish that move upstream into headwaters to spawn, such as anadromous salmon, have their habitat significantly reduced when a new culvert presents an additional barrier.

Many biologists and members of the public are just beginning to realize the importance of fish passage through culverts, and this is shown in the push to install more fish-friendly culverts, or bridges as an alternative. 

Read the full article here

In this week’s fishing report, Regional Fisheries Biologist David Basley, of the Maine Department of Inland Fisheries and Wildlife, explains the process by which Maine biologists use trap nets to sample fish populations in regional lakes and ponds. 

With fall fast approaching, staff in the Fish River Lakes region will be setting trap nets in Long Lake to sample landlocked salmon and brook trout.  These nets are designed to capture fish that are traveling the shoreline as the water cools.  Trap nets are not effective in the summer because the shallow water is too warm for salmonids to be present.  

The nets are designed to capture fish alive and act much as a herring weir on the coast.  A lead that consists of a fine mesh net 50-100 feet in length is stretched from shore and tied to a net that somewhat resembles a minnow trap.  That is it has a funnel that the fish swim through guided by a set of “wings” into the holding box of the net that is generally 4 ft x 4 ft or larger.  All fish captured stay in the holding box until fisheries personnel arrive to process the fish.  

Processing consists of netting the fish and separating the game fish from non-game species.  Game fish are held in a tub of water and anesthetized with a sedative to prevent injury.  One anesthetized, the salmon will be checked for missing fins indicating year of stocking, measured, weighed and released into another tub of water to recover from the sedative.  Brook trout will also be checked for missing fins because although the sport fishery in Long Lake is from wild fish, an occasional hatchery trout will migrate into the lake from another water.  The trout will be measured, weighed and a scale sample removed from female and immature fish prior to being put in the recovery tub.  This scale sample will be examined under a microscope at a later date for age determination.  Scale samples are also taken from female and immature wild salmon.  Changes in the external physical character of sexually mature male brook trout and salmon make it difficult to collect a scale sample from these fish.  Prior to release into the lake, a piece of the tail is clipped to identify the fish as having been processed should it be recaptured again at a later date.  

Trap net data allow biologists to follow age and growth of stocked fish in those waters annually stocked with salmonids. These data in conjunction with any creel survey information can be used to make necessary adjustments in stocking programs.  Data from waters with wild salmonid fisheries can assist in evaluating the effectiveness of regulations in maintaining suitable growth rate and abundance of these wild populations.

-Dave Basley, Regional Fisheries Biologist

The Idaho Department of Fish and Game is considering allowing anglers to harvest a limited number of bull trout in Lake Pend O’Reille, the northern Idaho lake where bull trout, as well as the popular kokanee salmon, have been threatened by the introduction of nonnative lake trout.  Bull trout are a threatened species under the Endangered Species Act, but may be harvested under special circumstances with permission from the U.S. Fish and Wildlife Service.  It sounds like Fish and Game biologists are trying to balance numbers of bull trout and kokanee in the presence of lake trout, which can often be very tough.  The Department is seeking public comment on the proposed decision.

See the details here

In an era of increasing concern for fish species and habitat restoration, the search for renewable energy can often conflict with the best interest of fish.

Seven new hydro plants are in the planning stages in Scotland, in an effort by the country to move to more renewable sources of energy.  It’s hard to understand why such development is being considered in Scotland while Americans are spending tons of money to remove dams because of their effects on fish.  The hydropower plans are opposed solely because of concerns for the Atlantic salmon and brown trout populations they have the potential to effect.  Dams are known to impede, and sometimes completely eliminate upstream migration of fish, and anadromous fish such as Atlantic salmon need to move upstream from the ocean to spawn. 

See the story here

While dams can benefit anglers in certain situations (especially in streams where migration is not necessary to support a fish population), and can provide substantial benefits to the public, they can often cause significant damage.  To support such development, I think the conservationist and angler alike should be confident that the designs of such dams result in minimal impacts to fish populations.  Furthermore, I think alternative sources of energy should be further pursued (such as wood biomass, wind power, solar power, and nuclear power) if the public is seeking a replacement for traditional energy generation.

I just got back from a field trip in Yellowstone National Park for a Stream Ecology course I’m taking at Utah State.  We investigated stream communities throughout the park, and got to see some great scenery.  Unfortunately, I didn’t get a chance to fish, but hopefully that’ll change in a few weeks, when I head back to West Yellowstone for a trout conference.