Tag Archives: science

Critics still talking crap about farmed salmon poop

trashtalkycows

The entire BC farmed salmon industry produces about as much poop every year as 409 dairy cows.

That’s it. That’s barely the equivalent of two average-sized BC dairy farms.

This is important because one of the most common criticisms leveled at salmon farms is that they are using the ocean as an “open sewer.” As usual, the risks are vastly blown out of proportion.

Our favourite activist Alexandra Morton likes to say that salmon farmers are one of the only farmers that “don’t have to shovel their manure” and that we should all be very concerned and scared of farmed salmon poop because there’s so much of it and it’s full of “chemicals.”

We hear or read this one at least a few times each week. And it’s true. It’s also true that, as usual, Morton is telling half-truths distorted by her obsession with the scatology of salmon.

So how bad is it really? Well, for one thing, fish poop is a lot more benign than human poop because they eat a way healthier diet than most of us. And for another thing, recent research shows the environmental impacts are hardly noticeable.

 

Old data, old arguments

Before we get to the new data, we have to consider the old, and it’s really old. The tidbits of info you’ve probably heard are almost all certainly based on information published back when the Vancouver Canucks still played in Pacific Coliseum.

Some environmental activists still claim (without providing a source) that a farm of “200,000 fish can produce as much fecal matter per year as a city of 62,000 people.”

Others, quoting even more ancient sources from the 1980s and 1990s, claim that the waste from a farm is equivalent to a city the size of Victoria, BC.

They’re all wrong. Time to catch up to the latest science.

The Hardangerfjord in Norway produces as much farmed salmon as all of BC. Plus it makes a great desktop wallpaper.
The Hardangerfjord in Norway produces as much farmed salmon as all of BC. Plus it makes a great desktop wallpaper.

Studying the Hardangerfjord

The Hardangerfjord is the second-largest fjord in Norway and possibly the most beautiful. It’s also home to enough salmon farms to produce 70,000 metric tonnes of fish each year. That’s nearly equivalent to the total capacity of all salmon farms in BC.

According to research published just two years ago, all the salmon farms in the Hardangerfjord produce 7,000 tonnes of particulate organic waste (as well as organic phosphorus and nitrogen, included in the 7,000 tonne total); 127 tonnes of dissolved inorganic phosphorus and 770 tonnes of dissolved inorganic nitrogen.

So all the farmed salmon in the Hardangerfjord produce 7,897 tonnes of waste. Considering that the BC industry is very similar to the farms in Hardangerfjord, with very similar fish, feeding practices and almost identical feed, it’s pretty safe to assume that the BC industry produces about the same amount of waste per year as Hardangerfjord.

Fish poop vs human poop vs cow poop

The average human makes about 128 grams of poop each day (more after Taco Tuesdays). That’s 46.72 kilograms per year.

The average dairy cow produces 19.6 tonnes of poop (and urine) per year.

That means all the salmon farms in BC, all around Vancouver Island, produce as much poop as 169,028 people each year, and as much poop as 409 dairy cows. 

We can’t think of another farming industry that produces so much healthy protein with such little waste.

So next time someone tells you that one salmon farm produces as much poop as a city, you can tell them that’s just a load of crap.

Salmon aquaculture virus study leaves one big unanswered question

A study by Norwegian researchers published late last month is apparently ” the first study confirming the presence of virus-infected escaped farmed Atlantic salmon in a nearby river shortly after escaping.”

The study makes some interesting speculations:

The recapture of the infected escaped salmon in nearby marine sites highlights the potential contribution of escapees in virus transmission to other salmon farms in the area.

…little is known about the effect of viral disease outbreaks in aquaculture on the wild salmonid populations. Disease outbreaks in salmon farms may lead to a substantial increase in infection pressure on wild fish in the surrounding area.

…escaped salmon may disperse over long distances, may enter rivers and may interact with wild conspecifics in their habitats. Therefore, an infected escapee may spread pathogens from the sea to wild fish populations in both sea and rivers distant from a disease outbreak.

That’s interesting, but there’s one big problem, which the researchers acknowledge.

…baseline data from the river regarding these viral infections in salmonids are lacking.

They cannot answer the question: how do the levels of viral loading on farmed salmon escapees compare to the natural viral loads in wild salmon?

As Yoda once said:

ControlToo bad this flaw doesn’t stop their speculation.

This could have been an excellent study if the researchers had taken some time to get data on wild fish in the rivers where escapees were found and sampled. Of course, wild fish sampled from these rivers post-escape would not provide any valuable baseline data, but they could at least provide information about viral loading in wild fish.

And the researchers could have also gotten some control data from other similar rivers where no escapees are found.

But it seems that in the rush to be able to declare this paper the “first” at something, or because it was outside the scope of the finding grant, they decided to sacrifice context in favour of speculation.

At least it does provide some good information about viral loading in escaped farmed salmon in Norway. It will undoubtedly be valuable to the researchers that decide to investigate natural viral loading in wild fish in Norwegian rivers.

One key to preserving our planet will be eating more farmed seafood, less pork and beef

US seafood consumption

“If 3 billion people move up into the middle class between now and 2050 and they are eating primarily beef and pork, the planet is going to be in a lot of trouble. The growing middle class should be eating seafood, rather than terrestrial animals. Aquaculture provides a clear way to scale and meet these growing demands.”

That’s one of the many excellent points in favour of aquaculture in a white paper prepared for the upcoming SeaWeb Seafood Summit in New Orleans next month.

The paper, titled “Aquaculture’s Prominent Role in Feeding a Growing Global Population,” was written by two heavy-hitters involved in aquaculture and seafood research: Dr. Michael Tlusty, director of Ocean Sustainability Science at the New England Aquarium, and Neil Sims, co-founder of Kampachi Farms LLC.

Reputation

The paper points out that aquaculture has suffered a bad rap in the past but people need to take another look.

“Aquaculture today is far different than it was 30 years ago because there is better rule setting and environmental monitoring,” the paper states.

Farms depend on clean environment

And the paper reminds us all that many fish farmers depend on a healthy environment — it’s in their best interests to keep the ocean environment clean, despite the claims of anti-aquaculture activists that net pens pollute and promote disease.

“In many cases, aquaculture involves farming species that haven’t been domesticated. They are inextricably linked to their environment, which is why we must pay such close attention to that environment. Because when we start tipping that balance towards too much production, the farms will lose money because they will lose animals. This also leads to environmental impact.”

Read the whole paper by registering at Seafood Source.

Alternatively, download it here.

Recycling your old iPhones… with salmon semen

This story was too weird to pass up:

“Japanese scientists have discovered that salmon semen from industrial fish farms could help to recycle rare earth metals.

Researchers led by Yoshio Takahashi from the University of Tokyo, found that salmon semen, known as milt, can be used in a process to extract certain rare earth elements that are used in products such as catalysts, alloys, magnets, optics, lasers and notably mobile phones.”

Only from Japan: salmon semen can help recycle electronics. Apparently.
Only from Japan: salmon semen can help recycle electronics. Apparently.

Apparently the semen, known as milt, “has the capacity to bind to positively charged ion material” making it a potential replacement for many caustic and dangerous chemicals currently used in the electronics recycling process.

The craziest part about this story is that there is a huge source of material available.

According to the paper, “More than 10,000 tonnes per year of milt from salmon, trout and others have been discarded as industrial wastes from fishery industries in Hokkaido, Japan.”

Again that’s

10,000 TONNES OF SALMON SEMEN.

BC salmon farms only raise about 70,000 tonnes of fish per year. There’s no way that there’s that much milt being used, let alone discarded, in BC. Japan doesn’t farm salmon on any significant scale, certainly not enough to produce that much milt.

This milt must be leftover from Japan’s massive “salmon ranching” aquaculture enhancement projects, which release more than 1 billion Pacific salmon from Hokkaido Island (referred to in this study) each year.

Aquaculture antibiotics study needs more context

A new study about antibiotics in aquaculture was recently published in the Journal of Hazardous Materials, and although it provides some good, useful data, it doesn’t mean much without more information.

Study highlights

  • 5 out of 47 antibiotics were detected in shrimp, salmon, tilapia and trout.
  • Oxytetracycline is the most commonly detected antibiotic compound.
  • Antibiotic resistant bacteria in seafood increase >8-fold in the last 3 decades.
  • We report a low risk of drug exposure from consumption of U.S. seafoods.
  • We recommend vigilance toward stemming microbial risks.

Sounds pretty innocuous, but as usual, the data is already being used by third parties to suggest that antibiotic usage in seafood farming is high and a potential problem.

Not true.

Let’s clarify one thing. Seafood farming and aquaculture have different meanings. Aquaculture is a far more general term, which includes farming as well as enhancement projects.

Wild salmon DO do drugs

Let’s use the definition supplied by the American Fisheries Society.

Aquaculture is an established and growing industry in the U.S., and an increasingly important supplier of foods for U.S. consumers.

The industry also produces baitfish for sport-fishing and ornamental fish for the pet trade.

In addition, federal and state fish hatcheries raise millions of fish for stocking in U.S. waters to support commercial and recreational fisheries and species restoration efforts.

Aquaculture is an important contributor to U.S. agriculture and a cornerstone of aquatic natural resources management.

All aquaculture operations will have a demand for drugs, biologics, and other chemicals, collectively referred to as “regulated products”.

There you have it: wild salmon DO do drugs!

Unfortunately, while this new study looked at five common species, including farmed American catfish, it did not look at any aquaculture-raised American salmonids. This is a glaring oversight, considering that billions of them are raised in aquaculture facilities and released every year on the Pacific coast.

It would be very interesting to see what sort of amounts of antibiotics are used in Pacific salmonid enhancement facilities in Canada and the USA.

Antibiotic resistance predates antibiotics!

Research published in 2011 adds even more interesting context to this study.

It suggests that making judgements about antibiotic resistance in aquaculture may be difficult: DNA from 30,000 year old microbes recovered from permafrost show antibiotic resistant traits similar to their modern counterparts.

Related stories

Antibiotics in aquaculture: getting the facts straight

Alexandra Morton’s furunculosis fable

Cooke Aquaculture gets sued for alleged patent infringement

Cooke Aquaculture, which raises farmed Atlantic salmon on Canada’s east coast, is getting sued by MariCal Inc and Europharma for allegedly violating patents.

There isn’t a whole lot of information available right now, but the Bangor Daily News in Maine has a report:

“MariCal granted a license to Cooke Aquaculture to use processes under four MariCal patents, but the contract between the two companies expired in 2008, according to the lawsuit.

Each of the four legal counts — one for each patent — alleges that Cooke Aquaculture and its affiliated businesses have been and continue to infringe on the claims of the patents.

Europharma AS is the exclusive licensee of the rights to the four patents, according to the lawsuit, and Europharma Inc. is a sublicensee of those rights.”

We’ll be watching to see how this turns out.

Salmon farm helping train the next generation of crime scene investigators

hammer
A fourth-year student demonstrates bloodstain pattern analysis with a hammer at the University of Windsor on March 21, 2014. From the Windsor Star, March 25, 2014.

It’s a small connection, but a fascinating one.

Blood from a Chinook salmon farm off Quadra Island is being used in the world-class Forensic Sciences program at the University of Windsor, Ontario.

The salmon blood is used to create blood stains on a T-shirt, and the second-year students are challenged to solve a “whodunnit.”

We use fish blood to create realistic blood stains on clothing and challenge the students to use DNA analyses to clear or implicate suspects.Safety concerns are minimized through the use of fish blood, while maximizing both realism and the likelihood of student success due to fishes’ nucleated red blood cells.

The goal in designing this laboratory exercise was to create a feasible protocol for large (over 300 students) second year university courses.

During two 3 hour laboratory sessions, students learn and apply clean/sterile technique, DNA extraction, polymerase chain reaction, restriction fragment length polymorphisms, and agarose gel electrophoresis. The students also learn to interpret the resulting gel bands in terms of inclusive or exclusive evidence.

Students have consistently ranked this lab as their favorite of five taken as part of a second year Genetics course.

Sounds like fun, and makes us wanna go back to school.

Here’s a published paper about the salmon blood experiment, and how it worked out.