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[troutbreath]

Fertilizers boost declining B.C. fish populations
 Fry grow up to 95-per-cent bigger in streams treated with nutrients, fisheries biologists say
 By RANDY SHORE, Vancouver SunFebruary 14, 2011 5:14 AM
 
 Young steelhead and salmon grew dramatically in streams seeded with sacks of slow-release fertilizer, a method that shows real promise to help rebuild collapsed spawning populations, according to B.C. biologists.
Photograph by: Ric Ernst, PNG filesVANCOUVER - Young steelhead and salmon grew dramatically in streams seeded with sacks of slow-release fertilizer, a method that shows real promise to help rebuild collapsed spawning populations, according to B.C. biologists.

The method has proven effective at improving steelhead growth and survival in Vancouver Island streams in programs dating back to 1989.

Steelhead fry in treated areas are typically about 95-per-cent larger than those in untreated streams, while coho fry are about 40-per-cent bigger. Fish counts in the Keogh River found a 50-per-cent increase in the number of coho that survived the freshwater stage of life.

Fisheries biologists are using fertilizers to replace the nutrients that would be added to the stream naturally by the rotting carcasses of fish that die after spawning, said Kevin Pellett of the B.C. Conservation Foundation. Enhancement programs are operating in 15 watersheds and 28 rivers on the Island and southwestern B.C.

When spawners fail to return, die and rot due to overfishing or ecological conditions, the entire food chain of the stream, from algae and insects to fish fry, goes into decline.

The fertilizers are designed to stimulate growth of certain algaes that in turn cause the populations of insects such as mayfly and stonefly to thrive. Juvenile salmon and steelhead fry feed on those insects.

“When you fertilize a stream it really stimulates algae growth,” said Pellett. “It’s the brown slime that we are really after because the key insects prefer the brown diatomaceous algae.”

Steelhead fry growing downstream from the fertilizer caches are bigger and typically 75- to 250-per-cent heavier than those upstream, which would not be expected to benefit from the improved food supply, according to the most recent data. Larger, more robust fish are more likely to survive and return as spawning adults.

“When those fish go into key overwintering periods, that’s where you see a lot of mortality,” Pellett said.

“The bigger those fish are, the more of them will survive.”

The first application of fertilizer is timed to benefit the tiny steelhead and coho fry that hatch and emerge from the stream bed gravel in the early spring.

Since the first stream enhancement programs started in 1989, a variety of fertilizers and delivery systems have been employed, including liquid fertilizers and fish meal.

“We’ve since switched to a new product called Crystal Green,” he said.

Crystal Green is a slow-release agricultural fertilizer comprised of nitrogen and phosphate recovered from municipal waste water using a technology invented by civil engineers at the University of B.C. The Vancouver-based manufacturer, Ostara, is harvesting a waste material called struvite for the fertilizer from the sewage stream in suburban Portland.

“This is not a panacea, but it is a good tool to increase productivity and it may increase the rate of rebuilding [spawning populations] if we see an increase in the ocean survival,” according to Greg Wilson of the Ministry of Natural Resource Operations.

“[Struvite] is one of the most cost-effective techniques that we have to help out populations,” said Wilson. “Using recycled phosphorus really reduces the carbon footprint of the project, because fertilizer is quite energy intensive to make.”

Testing on Crystal Green showed the material is extraordinarily pure with few measurable contaminants or metals.

“It’s the cleanest fertilizer we’ve ever worked with,” said Wilson.

Metro Vancouver is running a pilot project at the Lulu Island sewage treatment facility to produce its own version of the fertilizer to be used in the Seymour River, Wilson said.

Crystal Green Pellets are dropped into the stream in burlap sacks, which decay over time. That simple system eliminates the need for expensive liquid fertilizer delivery systems that require maintenance and that are prone to vandalism.

The concept of fertilizing fish habitat dates back thousands of years to China, where carp ponds were fertilized with human feces, Wilson explained.

More recently, the federal and provincial governments have partnered with conservation organizations since the 1990s to fertilize a number of lakes in B.C. with the aim of improving trout and kokanee salmon populations.

Nutrient additions to the Allouette Reservoir in 1999 generated a 12-fold increase in the resident kokanee population and sparked the first adult sockeye returns to the reservoir since 1928, he said.

That unexpected result gives fisheries biologists hope that this approach could help B.C.’s collapsed salmon spawning populations recover enough to become self-sufficient again.

Steelhead and coho in the test streams benefit from two seasons of enhanced growth, the first as tiny fry and the second as a smolt ready to begin its adult life.

Pellett says hatchery data show that the larger salmon smolts are when they leave freshwater for salt water, the more adult spawners return. Fertilizer-based enhancement programs are sending bigger smolts to sea and more smolts overall.

“The more smolts we send out the more adults we get back,” he said.

As spawning populations grow, the rotting carcasses of dead spawners are expected to regain their position as the natural source of elemental nutrients in spawning streams.

“We are starting to see critical mass developing in the steelhead and coho populations on Vancouver Island,” Pellett said.

The Vancouver Island fertilizer enhancement programs are run by the B.C. Conservation Foundation with support from the province, Living Rivers — Georgia Basin Vancouver Island, Habitat Conservation Trust Foundation and a handful of other conservation organizations.

rshore@vancouversun.com

© Copyright (c) The Vancouver Sun
   Young steelhead and salmon grew dramatically in streams seeded with sacks of slow-release fertilizer, a method that shows real promise to help rebuild collapsed spawning populations, according to B.C. biologists.Photograph by: Ric Ernst, PNG files 

[skaha]

-Crystal Green is a slow-release agricultural fertilizer comprised of nitrogen and phosphate recovered from municipal waste water using a technology invented by civil engineers at the University of B.C. The Vancouver-based manufacturer, Ostara, is harvesting a waste material called struvite for the fertilizer from the sewage stream in suburban Portland.

-Testing on Crystal Green showed the material is extraordinarily pure with few measurable contaminants or metals

--That's great to hear... you coastal guys must have a more pure **** that we do in the interior as we were denied a permit to use municipal waste water for fertilize logging roads and landings... reason given...cows would eat the grass that grew which would be high in heavy metals. Also run off from roads may get into streams.

--Now I know this is very simplistic view as we need to target where and what nutrients are added, however it seems the same argument's of fact are given for both positive and negative results..
--Other reason given... There is no accurate test to guarantee the amount of heavy metals and no standard for amount of heavy metals.. so I guess these companies have now solved these issues.

[bigblue]

Good to hear that something can be done for the rivers flowing out of dams in the lower mainland.
Water flowing out of dams are so clean and cold, devoid of nutrients, that normal biological activity is very difficult.
Left to itself, these rivers will never regain it's past productivity for steelhead or any other species for that matter.
Human intervention is not always the most desirable option, but some rivers can really use a dose of help to get things going.

[Dogbreath]

I suppose soylent green is too contaminated......

[Dave]

The Chilliwack River Action Committee, Fraser Valley Salmon Society, and Chilliwack Fish and Game Protective Association has been supporting and often funding this program on the Chilliwack-Vedder for a few years now. It's a science proven, easy, relatively cheap and great program for increasing survival rates of eventual steelhead, coho and possibly summer red chinook smolts.  It benefits other fish also, like char and whitefish - higher survival rates on all these fish species is money in the bank for predators like herons, mergansers, dippers, mink, otters. etc.   It's all good.

Best thing enhancement wise happening now on the C-V, IMO

[skaha]

--I'm all for it just don't scrimp on funds to monitor and measure the program.. Remember Mysis shrimp were great for 5 or more years and still are in some systems. It was when the practice became a routine solution without rigorous protocols for use or follow up, that these critters got out of hand in some systems causing a crash in kokanee populations.

[BwiBwi]

Skaha, extraction method has major role in purity of final product.  You can't compare a diluted **** with extracts.     

[skaha]

--I'll presume the engineers have developed an appropriate extraction method and are producing a "safe" product. The monitor and follow up I was referring to was on the fish population.  In some systems fish developing at a more rapid rate due to available nutrient may not be an advantage... they may migrate at a different time of year or being larger size earlier than rest of the river may attract more predators etc.

[shuswapsteve]

Some may be surprised to know that fertilization of watersheds in the province is not a new concept.  Go to google and type "Stockner lake fertilization" and you will see some history on some of the projects previously conducted in this province.

[Dave]

John Stockner and his colleagues Erl MacIsaac and Ken Shortreed, along with others, were indeed pioneers in the field of supplementing lacking nutrients in sockeye rearing lakes.  I'm happy to see this science being used more now in N-P-K deficient coastal streams.

skaha, I believe there is an ongoing monitoring program on the Chilliwack-Vedder but funding is always an issue and I'm not sure if it happened this year- perhaps other readers can help here (you know who you are).  As to larger parr attracting more predators... perhaps that could be a problem on some systems but for an urban watershed like the C-V, with so many people using the system for other than angling experiences, I don't see it being a problem.

[JRTMACD]

Frankly, if it safely increases the stocks of sport fish in the local rivers I'm all for it. I doubt there is a single steelheader out there that wouldn't want to see the steelhead population be recovered to early 1980s levels. Now if only we can get the government to actively fund it with more than just token donations.

[aquapaloosa]

I wonder if you could incorporate a marker in the fertilizers for imprinting in out going juveniles as a more natural enhancement tool.
  For example:  River A has been using a marker(in the fertilizer) (M1) for four years and River B has been using Marker M2 in its fertilizer for four years.  The four year old fish will be returning to there original imprinted markers but River A is expecting a large return and river B is not.  So in in order to get more fish into River B from River A they could use a the M1 marker added to the M2 marker already in River B to bring in more returning spawners fish from river A. 
  Question is what in the water are the fish using as markers in the wild now and could man made markers override natural ones or even make a difference.


 

[skaha]

---"Question is what in the water are the fish using as markers in the wild now and could man made markers override natural ones or even make a difference."

--Interesting concept... maybe could get hatchery stock to return to a pen rather than commingle with naturals.

--As to monitoring, I have never seen government follow through on long term monitoring. Without measurement of the results the experiments are essentially useless.

--If it seems to work... no obvious issues and the public begins to buy in what often seems to happen is we repeat the success to excess until we achieve failure.
--We tend to focus on what we can see which is  a healthy looking larger individual in a relatively small geographic population... once we get to a larger community or ecosystem level it is much more difficult to define success.
--Much of my experience has been with the sockeye cousin.. the kokanee... at least the kokanee stay in a lake where it is much more easy to measure and monitor than a critter that takes off for part of its life into the great blue yonder... We have of course used fertilizer as part of several kokanee recovery programs... again lack of credible data and specific measurables of success really amount to nothing more than a gut feeling the programs work .. its not science.. any first year student that submitted a project without measurable results would fail... I can attest to this lesson learned from a research paper which only tended to indicate seasonal fluctuation in the population of  zooplankton in Kamloops lake.

[Dave]

Excellent points skaha.
Of course monitoring programs for projects like these are essential and (I am only speaking for the C-V) it's my understanding ongoing periphyton/salmonid sampling is happening.  Again I ask readers with more information to respond.  Unfortunately and sadly how this fertiliztion program impacts adult returns is not monitored.

aquapaloosa, it seems we have a hard enough time finding $$ for the fertilizer, let alone incorporating markers, though I like idea.  Great project for a grad student .

[Chrome Mykiss]

Here is a video I made while we were implementing the stream fertilization program on Statlu creek. As you can see, with all the hard working volunteers it was a quick process getting all those bags of poop in to the creek  
http://www.youtube.com/watch?v=leSk-35aj8Y