Monday, 5 March 2018

Otto Langer on Farmed Fish - Escapes Through Leakage between 153,000 and 500,000 in BC, Updated Apr 16, 2018

Fish farms say WA closing fish farms is an emotional response to a single escape, failing to point out that in BC 'leakage/escape' releases as many as 500,000 farmed fish per year without them being reported:

Read below, or read the Langer document at:

First, though, Otto Langer makes the important point about raising salmon cheaply: "Feed is expensive, and the production objective is to maximize the conversion of feed into growth while
minimizing loss of fish due to disease, parasitism and escapes. To this end,
farmed salmon brood stock are selected for performance traits such as high
food conversion rate, rapid growth, delayed age of maturity, and resistance
to diseases and parasites. Their behaviour, physiology and morphology are
significantly altered from those of wild fish, partly through genetic selection
and partly through the rearing they experience (Fleming et al. 1994, Gross 1998)."

Now, the thing is that fish farms are constantly crowing about their declining food conversion rates, mostly to show that they are not killing off the worlds fish, that Daniel Pauley/Tim Cashion point out they have  been so successful at that 19, out of 20 global forage fish stocks are either collapsing, badly managed or both. Check out the Sea Around Us document on reduction fisheries:

So, the point is that fish farms have no choice, having killed off so many global fish stocks, that they don't have many left to pillage. And, on the other side, to reduce costs, they are raising fish genetically grown to use less fish in growing. Technically, this is not a GMO issue, but I leave it to a reader, who may be concerned about GMO products to mull this over.

Now let's move on to escapes. Just how how many  do escape in BC? Well, Langer says this: "How many fish are escaping? No one really knows. The 30,689 fish per year that are reported as escaped (average from 1991-1998; Noakes et al. 2000) is surely a significant underestimate. Some members of the industry estimate a 0.3-0.5% escape rate (Wilson 2000a); however, various sources of data suggest that 2-5% or even higher may be likely. Leakage, or continuous small-scale escape, may itself exceed 0.5%. Some escapes are quite massive, such as the 390,000 farmed chinook salmon escaping in BC in 1989 (Wilson 2000b), or the 360,000 Atlantic salmon escaping from a single farm in Washington State in July 1997 (Gross 1998). A conservative estimate of 3% per year, the upper limit recommended by the 1997 Salmon Aquaculture Review, suggests that...140 roughly 350,000 fish may have escaped in BC in 2000 (calculations partially based on quotes that industry claims the 35,000 escapees by 24 August 2000represent 0.3% of their production; Hauka 2000, Hasselback 2000). There is need for a more reliable method of assessing escapement rates."

This is staggering, and why Volpe, who has done the studies on Atlantics in Van Isle rivers, says that 97% of Island rivers surveyed, with multiple Pacific salmonids, have farmed Atlantic escapers. Hard to believe it can be that high.

So, the mid-ground on this one is 1% for leakage/escape events. And here is the calculation: 85 Farms X 600,000 fish X .01 = 500,000 fish escape per crop in BC. That is also staggering. If you use the absolute lowest rate it is: 85 X 600,000 X .003 = 153,000 escapes per crop.
So, what else? This: "several major escapes of Atlantic salmon during the summer of 2000 led the Minister of Fisheries to repeal 5 of the licenses."
This means that the precedent for eliminating fish farms in the ocean has already been set in BC. Today, 2018, is time to get the fish farms out of our waters that their 'externalities' like sewage are a far greater problem, and John Horgan/Andrew Weaver want them out. And look at this post to see more escapes in BC:

So,  and this: "Adult Atlantic salmon have been captured in the Bering Sea (Brodeur and Busby 1998) and in marine and fresh waters of Alaska despite the absence of fish farms in Alaska (W. Loy, Anchorage Daily News May 2002). In 2001 ASW recorded 179 adult Atlantic salmon in the year’s marine catch, 116 in 13 BC rivers, and 35 in the Alaska marine In the previous year Atlantic salmon made up 1.6% of the catch of salmon in a 24-hour fishery in the Strait of Georgia due to an undetected escape (K. Scarfo, President West Coast Trollers Association, 4 August 2000). Unfortunately, farmed chinook and coho are more difficult to identify and go largely undetected in catch records."

And, this: " In the past, some industry and government leaders have denied that  colonization is possible, yet by 1996 all life stages of Atlantic salmon (alevins, parr, and adults) had been reported escaping and by 1998 adults had been found in 75 rivers. By 1999, feral (wild-born) juvenile Atlantic salmon were found in several rivers (Volpe et al. 2000). Escaped Atlantic salmon can therefore survive in the Pacific Ocean, migrate at an appropriate time into fresh water, perform appropriate intraspecific reproductive beha-viour, produce embryos and alevins that survive, and the resulting juveniles can successfully obtain food, avoid predators and survive across years. What remains to be shown is whether the juveniles will reach adulthood and reproduce. The complete colonization cycle has therefore not been shown, but this is a likely outcome based on mathematical models of invasion probabilities (Gross 2000). The central issue about Atlantic salmon is probably not whether they can colonize, but the degree of impact that they may have on wild Pacific salmon stocks (and other species) if they do."

And the stats on ISA disease are: "ISA is a highly contagious and lethal viral disease that spreads by horizontal transmission (adult to adult) in both freshwater and seawater. The disease was unknown to science before appearing as an epidemic in the Norwegian salmon farming industry in 1984. Within seven years, it had spread to 101 farms and
remains a problem today. In Canada, ISA was first observed in New Brunswick in 1996 and spread to 21 farm sites by 1997, and 35 by 1998. Despite widespread culling, 17 sites remain contaminated. In 1999, wild Atlantic salmon in New Brunswick were found for the first time to have the disease, and escaped farmed salmon entering freshwater to spawn were found to carryit. In Scotland, ISA was first reported in 1998. By 1999, about 10% of all Scottish sites were infected, and the disease was found in wild salmon parr. In
Chile, ISA was reported in early 2000 in farmed coho salmon. In Maine, USA, ISA appeared in early 2001 and greatly impacted the farming industry. The virus is believed to be carried in mucus, urine and feces and its amplification in farms therefore creates contagious areas for nearby wild salmon, in addition to its transmission by escapees."

The escape number alone is reason to get fish farms out of the BC ocean. And you will recall Jeremy Dunn crowing about how well managed BC fish farms are. But, losing a half million fish per year is not managing well.

Here is another estimate of BC escapes, note it being .5- to 1%:  "Research done in BC estimates that 0.5 to 1 percent of juvenile Atlantic salmon in production “leak” from their pens each year.6 If we assume that 1% of the approximately 80,000 tonnes of farmed salmon currently produced each year in BC is leaked, this translates into approximately 160,000 additional farmed salmon escaping into BC’s marine environment on a yearly basis."


 And the penalties, you ask? Peanuts:  Meanwhile, very little in the way of penalties or fines are levied against the offending companies. For instance, the most recent Annual Inspection Report on Marine Finfish Aquaculture Sites (2008) issued by BCMAL shows only one violation for “failure to report a possible escape” with a fine of $173.8

Also from the last source, farmed and dangerous.

 And, what does this mean about the laws?  "With escapes on the rise in recent years, incomplete data on the full extent of escapes and minimal repercussions for escape events, it’s clear that BC’s salmon farming regulations are not adequate. These lax regulations are an example of how the government continues to enable salmon farming companies to externalize the costs of a dirty, unsustainable industry onto the environment and people of British Columbia."

Also from the last source.

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