Take Action for Little Fish

Maybe you have seen this going around about the Little Fish our big fish eat?  Pew has been pushing this around for a while, and you know what, they are spot on.  As fishermen, sport and commercial, we fight over allocation, we fight over hatchery releases, and we all are overwhelmed with the issues of habitat.  All this has to do with what is going down on land.  There is something we can do that is pretty simple and gets us ahead of the curve on a major issue in our oceans.  The increase harvest of Forage fish.

Forage fish are the herring, anchovies, sardines, dace, smelt, squid etc. that eat phytoplankton turning it into protein for the big stuff, like seals, salmon, steelhead and birds.  This increase in harvest in a volatile ocean, see the sardine issue, turns commercial fishermen to seek out new species to target for harvest often to feed fish farms.  Of all these little fish, only anchovies, market squid, Pacific herring, and sardines are regulated on the West Coast in the L48.  What Pew is suggesting, along with Trout Unlimited, Association of Northwest Steelheaders, Wild Steelhead Coalition and a slew of others, is they actually manage for the majority of species on an eco-system level.  This is the proposal from the Pacific Fisheries Management Council that fish folks are supporting.

These fish feed Steelhead and salmon, making them strong so they can swim to places as near to the ocean as Siletz, Oregon or as far as Salmon, Idaho, healthy fish are strong spawners and fight hard as well.  The other thing these little fish do is create massive bait balls at the mouths of some of our biggest rivers, like the Columbia. This provides incredible cover for outgoing smolt who run a gauntlet of birds, seals, and predator fish as they enter the ocean.

So take a minute and Take Action – Tell the Pacific Fisheries Management Council the time is now to protect unmanaged Forage Fish – Deadline for Comments is March 30^th.

Head over to http://www.tu.org/take-action and find the link titled “West Coast TU Members: Urge Fishery Managers to Protect Our Forage Fish”

What’s up with the steelhead stalkers?

The crew of the research vessel Chasina gets ready to drop an acoustic telemetry receiver 300 feet down into Puget Sound. The device will record tagged steelhead as they swim out of their spawning rivers. Credit: Ashley Ahearn

OPB radio recently provided a look into the research conducted by Megan Moore (NWFSC – NOAA) and colleagues on an early marine survival project. If you didn’t catch the program, it describes the sources and locations of steelhead smolt mortality upon leaving their natal river. The researchers are tagging wild and hatchery smolts, then tracking their movements (and survival) through Hood Canal in Washington to study where mortality is occurring and if differences between hatchery and wild fish are present.

Their most recent steelhead stalker project had the following 4 objectives:

1. Get a baseline survival estimate for two wild populations;
2. determine if conservation hatchery smolts had similar survival rates compared to wild smolts;
3. evaluate if wild and conservation hatchery smolts from the same population have similar behavioral traits, and;
4. locate hot spots of mortality during smolt migration.

The study was repeated over three years (2008-2010). Wild smolts were captured from two Hood Canal rivers and tagged with VEMCO acoustic tags. These tags emit an active signal (think along the lines of sonar) that is picked up by receivers positioned in migration corridors. Each tag has a unique ID code so individual fish can be tracked through their path of migration. The conservation hatchery fish were offspring of wild spawners and collected as recently fertilized embryos from the river (no artificial spawning involved).

Two different hatcheries were used to rear the fish. One hatchery (Duckabush population), was low-density with circular tanks and the second (Skokomish population), was higher-density (within conservation program guidelines) using raceways for rearing. The same tags were implanted in the hatchery fish and wild fish so there wasn’t a difference in tag effects.

To track the fish, four lines of receivers were deployed during the study. The first was at the river mouth of each river smolts were tagged in. The second was at the Hood Canal bridge, a third was made across Admiralty Inlet and the final array was spanning the Juan De Fuca Strait.

Program MARK, using a Cormack Jolly Seber survival model, was used to determine if any of the following five factors influenced survival;

1. population (river differences);
2. rearing type (hatchery vs wild);
3. hatchery (differences between two hatcheries used);
4. Skokomish (combined Duckabush wild and hatchery vs Skokomish hatchery), and;
5. Duckabush (combined Skokomish wild and hatchery vs Duckabush).

Three covariates (length, condition factor and release date) were included in all models as well. If you want more details on the analysis check out the pdf (I dare you…).

For survival probabilities of each population in each section of the migration click here. Wild fish had the highest survival probability, but the Duckabush hatchery smolts were not statistically different from wild fish. The Skokomish hatchery fish had lower survival in every migration segment except from the Hood Canal bridge to Admiralty Inlet. The Hood Canal bridge to Admiralty Inlet segment was the area of highest mortality for all populations. Release date has a slight positive effect on survival, meaning hatchery fish released later in the season had a slightly higher probability of survival. There were no differences between wild and hatchery populations in freshwater or saltwater migration behavior.

Let’s put this one in perspective. Some hatchery fish had indistinguishable survival rates from wild fish…score one for the conservation hatchery program! The other hatchery population (the Skokomish) had lower survival probabilities, but they were raised at higher densities in a raceway environment. Potentially higher-rearing density, or something unique to the raceway, had an effect on post-release survival.

A mortality “hot spot” was found in the migration pathway. Between Hood Canal bridge and Admiralty Inlet, all smolts had mortality rates up to 15 times higher than any other migration segment. The authors suggested that the subsurface bridge pontoons could be inhibiting the surface-oriented smolts during their migration. And just in the past year Moore, et al. have published another paper on the effects of the bridge on smolt survival. Stay tuned for that article in my next post.

—
Neil Thompson is a P.h.D. student at Oregon State University studying the drivers of domestication selection in hatchery culture of Pacific salmon and steelhead.  Find out more info on the lab where I work here.

Tipping Trees for Wild Fish

Tip waitresses for good service, tip trees for good wild fish.

Salmon Use Magnetic Field–Based Internal Maps to Find Their Way

A new study from a team OSU researchers, led by Nathan Putnam, recently published in the February 6th edition of Current Biology finds that steelhead and salmon use magnetic field-based internal maps to find their way back to their natal streams to spawn.

James Gould, an evolutionary biologist at Princeton University who was not involved in the study, wrote in a commentary on the paper that the fish may not have a map like the kind we might imagine, but instead something akin to an Excel spreadsheet, with “lists of magnetic coordinates with the seasonally appropriate directional responses filled in.” That is, the fish may simply perceive the magnetic field at a given location and, like a GPS, have essentially a voice command in its head that tells it where to swim. Putman thinks this is likely the case for the salmon. “If I had to bet, I would say that is probably what’s happening,” he says.

For a writeup of the study, see Scientific American online.  For the full study, click here.

OMSI Science Pub in Corvallis: Cry of the Pacific Lamprey: What This Ancient Fish Is Telling Us About Our Waters

Next Monday, join Carl Scheck of OSU and Jeremy Monroe of Freshwaters Illustrated at Old Wold Deli for OMSI Science Pub. The topic of the evening will be lamprey and what we can learn from these fascinating, ancient fish. 

Lamprey lack the charisma of Chinook salmon, steelhead or even the sturgeon. With a powerful mouth disc, lamprey latch onto other fish and suck out body fluids. Older than the dinosaurs, these ancient fish have successfully negotiated at least four planetary extinction events. However, they may not survive changes brought about by humans.

Monday, Feb. 10th, 2014

6-8 PM

Old World Deli – 341 2nd St. Corvallis, Oregon

[LINK] to OMSI science pub website

Mushrooms clean dirty Willamette River water

[LINK] to complete story from KVAL.com

The process used by volunteers with the Ocean Blue Project, an ecological restoration nonprofit, is to place mushroom spawn and a mixture of coffee grounds and straw in burlap bags that mushrooms can grow in, and then place the bags so that water entering storm drains will filter through them.

Oregon Department of Environmental Quality water sampling from 2008 to 2012 showed the presence of pesticides, flame retardants, metals, and chemical ingredients from consumer products in the river. The Oregon Health Authority also has an active mercury advisory warning that children should not eat more than one serving of resident species of fish from the main fork of the Willamette River a month, and that adults should not eat more than four servings. Complete Article [HERE].

Mushrooms are freaking sweet.

Bluebacks to conduct spawn and snorkel surveys on SF Siletz

Trout Unlimited’s local Corvallis Chapter, The Bluebacks, are undertaking a monitoring effort on the Upper South Fork of the Siletz above the old Valsetz Dam site.  The project will include both spawn surveys for steelhead “redds” and snorkel surveys to determine if juvenile salmon and steelhead are using the SF Siletz and its tributaries as rearing habitat.  The Bluebacks hope to engage the Corvallis community in “citizen science” to collect valuable data on fish populations in the Upper Siletz and provide educational opportunities for community members.

A few years ago, ideas began circulating about rebuilding a dam at the old Valsetz site, to create a reservoir to divert water from the SF Siletz to Polk and Lincoln counties for irrigation and municipal water uses.  Back in 2008, OPB ran a story and an accompanying article that summarizes the proposal pretty well here.  While that effort seems to be on the backburner, the Bluebacks are seeking to collect spawn and juvenile usage data for the Upper South Fork Siletz and some smaller tributaries to better inform any debate around future dam proposals and to gain understanding of native steelhead, Chinook, and trout populations in the Upper Siletz Basin.

Volunteer leaders are being trained in the middle of January, and spawn survey efforts will run from January through the middle of May.  The Bluebacks are seeking volunteers to participate in these spawn surveys, where groups will meet every other weekend at Moonshine State Park and drive to the survey sites.  Surveys will involve walking 1-2 miles of the reaches being monitored, looking for steelhead redds, or nests that spawning steelhead make to lay their eggs in.  The semi-weekly trips will take about a half day and will provide both beginners and experts experience with principles of fish biology and the opportunity to see wild, native steelhead spawning in their natal streams.

If you’d like more information on becoming a volunteer leader, or just participating in a volunteer survey day, contact Chapter Volunteer Coordinator Julie Nist, at bluebackstu@gmail.com, or head over to http://www.bluebacks.org/projects for a full monitoring calendar and more information on volunteer opportunities.

-KS

Fisheries drive evolution in fishes, but how fast?

It’s long been recognized and acknowledged that fisheries are inducing change in fish populations. When the largest individuals of a population are removed year after year, as results from commercial fishing, the overall body size and age of maturity of the population decreases. This makes sense: there are fewer large individuals to pass on their genes, and a greater number of smaller fish breed and contribute to the overall population. But the important questions are: (a) how fast is change occurring within these species and (b) what traits are most affected?

To answer these questions, a recent study by Audzijonyte et al. compared modeling studies (which are based on simulations) and experimental studies. More specifically, this study sought to investigate three areas: (1) Are the rates of evolution different between experimental and modeling studies? (2) Are certain traits affected more than others? (3) Do modeling studies differ in their estimated rates of fisheries-induced evolution?

To do this, the authors scanned the literature and came up with 14 modeling studies and an equal number of experimental studies, plus one review of experimental work. To easily compare all studies, they standardized to a common value of percent change in trait value per year. They then grouped traits into five categories; (1) size at maturity, (2) age at maturity, (3) median maturation reaction norm*, (4) growth, and (5) reproductive investment.

*A reaction norm is when, for example, a single species can express different phenotypes (observable traits/characteristics) depending on the environment it lives in.  A quick, illustrative example is from the Atlantic silverside. Silversides at lower latitude (warmer temperatures) have fewer vertebrae than silversides from higher latitudes (cold environment). One species differs its phenotype based on the environment (temperature) it lives in.*

What did the results show? For question one, rates of evolution were statistically significant. Modeling studies reported a range from 0.1 to 4% in trait change per year, while experimental studies ranged from 1.1 to 17.4% change per year. The difference means that modeling studies report a lower percent change per year than the experimental studies. Also, the effect of fishing pressure was consistent over all traits.

What traits are most affected? The authors analyzed modeling and experimental studies separately. In the modeling studies, the analyses showed that the five trait groups could be distilled into two major classifications: (1) traits for reproduction and growth; and (2) size and age at maturity. Those traits involved in age of first reproduction (classification 2) were found to evolve faster.

The results of the experimental studies were more complex. Only one trait classification could be made by combining the size at maturity, growth, and reaction norm traits. Age at maturity was affected the most. Complicating the result, however, is that with increasing fishing pressure, the change in trait values differed based on the trait being evaluated. This means some trait values changed more for a given amount of fishing pressure compared to others. The rate of change fishing pressure induced in reproductive traits was greater than the rate of change of age at maturity.

Question three is for those of you who are really into math and statistical model design. For the fish folks here’s the take-away: two classifications were found in the modeling studies and one was slower than the other. But, increasing fishing pressure increased rates of evolution equally in both classifications. If you want to know more, read the pdf.

So, let’s put all this into perspective. Four major results jump out of this work. (1) Experimental studies report rates of change that are faster than those of modeling studies. (2) Increasing fishing pressure changed evolutionary rates equally in experimental and modeling studies. (3) Traits associated with maturation and the time it takes to become mature evolve at a faster rate than growth or reproductive investment traits. And lastly, even though each modeling study used different methodologies, they all more or less came out with equal estimates of the rates of fishery induced evolution.

But do we care? Should we care? Those are questions for you to answer, not me. The results showed that a single year of fishing can change a particular trait from 0.1% all the way to 17%. That is astonishing. We can quibble about precise rates, but that isn’t truly important. What is important is that simply by fishing we (humans) can induce rapid phenotypic change in the fish we capture. By maintaining fisheries for large mature individuals a younger age at maturity is being selected for. This makes good sense, as the fish that reproduce early have a higher chance of escaping the fishery and passing on their genes. Surely other factors can and are driving phenotypic change in the fish we catch, but this study demonstrates that fishing pressure can have a major impact on fish we value as a food source.

Pacific Rivers Council O&C Happy Hour

What:            O&C Happy Hour and a screening of our short film: Forests to Faucets. Join Pacific Rivers Council after work Friday the 13^th, for FREE Hopworks Salmon Safe IPX beer, snacks, a short movie and discussion on current threats to many of Oregon’s most iconic rivers including the Sandy, Clackamas, Molalla, Nestucca, Trask, Umpqua and Rogue.

These rivers, and many others, will be impacted by proposals in Congress that would allow industrial timber harvest on our public lands. Please join the great folks at PRC to learn more about this issue!

When:           Friday, September 13 4:30 to 6:30, film starts at 5:30 PM

Where:          Ecotrust
The Natural Capital Center-Billy Frank Jr. Conference Center
721 NW 9th Ave. Portland, OR 97213
The Pacific Rivers Council, American Rivers and the Wild Salmon Center are working to ensure that the management of over 2.4 million acres of federally-owned, public lands in western Oregon (also known as O&C Lands) is not based solely on the most profitable way to log these forests, but on the best way to keep the Oregon economy strong, our salmon and steelhead populations intact, and our water clean. And we need your help!

RSVP on Facebook at on.fb.me/14yawyt

How Do Anadromous Fish Get Around Dams Without Fish Ladders?

Brandon Smith – KLCC

We have received numerous inquiries  regarding “very, very large dark fish” from anglers fishing the headwaters of Mckenzie and Middle Fork Willamette watersheds, so here is a recent article from KLCC public radio about how those Spring Chinook got there:

Every summer thousands of hatchery-raised Chinook salmon gather at the base of Dexter Dam. The dam was built in the 1950s without much thought for migrating fish. That’s made a lot of work the Oregon Department of Fish and Wildlife. Every adult salmon that is upriver of Dexter Dam is there because someone threw it into the back of a truck. There is simply no physical way for them to swim past Dexter Dam. – See the complete story [HERE] 

http://klcc.org/Feature.asp?FeatureID=4737