Wild salmon stocks 'wiped out' by sea lice

as a salmon farm employee of 27 years let me dispell some of the dross that is sometimes presented as fact by the press and some other "authorities" on the subject.
all salmon farms do their utmost to eradicate sea lice on our fish as a lice infestation can cause a 30% reduction in feeding and the introduction of infections caused by the lice.
in the critical spring period when salmon and sea trout smolts go to sea all farms are inspected on a 2 week basis to count the number of lice on the fish.the permitted numbers of oviderous females per fish is .5 per fish.if this number is exceeded thn the marine institute will tell the farm to do a treatmtnt.
the most widely used treatment at the moment is hydrogen peroxide, this is a oxidising agent which literaly lifts the lice off the fish whilst the peroxide itself bio degrades in 20 minutes in sea water.
salmon smolt when they migrate to sea do not hang around the bays and do in fact move out to sea at a very fast rate, a smolt that was micro tagged in the screeb fishery in connemara was recovered in a mackerel trawl off the mull of kintyre 8 days later.
in conclusion , salmon farms do their utmost to rid their fish of lice as it causes them large financial costs, they have a legal obligation to do so ,they also have an envoirnmental obligation.
lastly, there are no organicaly certified in feed treatments for sea lice treatment,but you will have to check with the 3 organic certification authorities that certify the fish that we produce to verify this.

Hi Joyster,

The fact remains, regardless of what alleged efforts you state that salmon farmers go to eradicate lice from their fish, lice problems persist. Lice problems which didnt exist in the vicinities of farms prior to their introduction. My first hand experience relates to a farm which was introduced exactly 22 years ago this month. 22 years into the operation and there are still sea trout being encountered with grossly excessive lice infestations to the point of being fatal. Several generations of sea lice on individual fish. It didnt happen before salmon farming was in the area, it is completely unnatural and it is killing wild fish.

A juvenile salmon can swim as fast as it likes away from the coast, if it swims through a high density of salmon louse nauplii it is doomed, speed of travel wont save it. Whats more, salmon smolts navigate by the coastline before heading off into the deep ocean as your example of a Screebe smolt being caught 8 days later off the Mull of Kintyre demonstrates. That fish has navigated the length of Ireland by its coastline and was very likely going to carry on northwards along the west of Scotland coastline, travelling through salmon farm occupied Scottish water en route. So your in attempts to argue that smolts are not vulnerable to salmon farm nurtured lice infestations, you have actually achieved the complete oppositte. Thanks for pointing out something we were all aware of initially- salmon smolts navigate by coastlines, ie salmon farm territory.

Even if salmon farms did their utmost to eradicate lice infestations on their own fish it still doesnt alter the fact that farms are permanent salmon louse breeding reservoirs which are not supposed to be there, evolution didnt plan for them. Farms dont have to have problematic infestations on their individual fish for there to be an absolutely giant lice production being released into the natural environment. Even if the number of egg bearing female lice is as low as 0.5 per farmed fish in a farm containing lets say 500,000 fish, thats still 250,000 egg releasing adult lice in a specific coastal ecosystem which shouldnt be there. The number of lice on your individual fish is irrelevent. Its the combined number of egg producing female lice on your stock which is the problem. Thats the reason I am catching sea trout on an annual basis with sickening infestations of sea lice present. The worst one Ive seen involved 18 fully grown adult lice and 293 immature transparent lice. The fish was a very disturbing sight, emaciated from the dorsal fin region rearwards. Thats the actual real result of salmon farming whether you like it or not, regardless of whether you attempt to control lice ot not. The fact is, you cannot control lice. You cannot prevent lice occuring on intensively farmed fish and you cannot prevent them from reproducing. Their offspring infest the wild fish's environment in densities which cannot possibly happen without the presence of salmon farming.

Please sign the 'Petition to prevent the further development of salmon farms in Ireland' on facebook.

If you live in the Bantry Bay area or Galway Bay you have disastrous proposals to expand salmon farming in you local waters happening right now.

If the farms go ahead coastal waters off the west of Ireland will never be the same again, containing billions of introduced salmon louse larvae, thousands of tonnes of sewage and a mixture of chemicals and medications.

Wild salmon and sea trout stocks WILL WITHOUT DOUBT BE REDUCED, ESPECIALLY SEA TROUT. This isn't scaremongering. It is observation and experience based fact. The impact of the proposed farms will be proportionate to their size, ie huge. Sea trout numbers are set to decline sharply around Galway Bay and Bantry Bay in particular if this goes ahead.

hi bredan,
i do not disput the fact that salmon farms have an impact on the envoirnment in which they are placed , it is so with any intensive farming enterprise.
what i would have issue with is the findings of various research reports that are produced. the report that you refer to would suggest that 39% of all smolt that go to sea are killed by the effects of lice predation however it does not establish where the source of these lice is , the impression given is that the only source of lice is from salmon farms which of course is not so.
i would be interested if anyone reading this could tell me how many of our coastal fish are carriers of sea lice,i can think of 9 off the top of my head.
the organic certification bodies allow 2 treatments if slice in the production cycle of a single generation of fish, the remainder of treatments are done with hydrogen peroxide and 2 other permitted bath treatments.
tanglerat was asking about the use of hydrogen peroxide, i have no problem using it properly. the treatments we do are either with a very large bag, 90m circum and 2m deep in which the fish are enclosed and the product added fo about 30 mins until the product has bio degraded, or we pump the fish into a well boat and do the treatment within the well.
one fact that is noticable from this thread is the huge lack of knowledge in regard the movements of smolt when they go to sea .

Thats a fairly typical attempt at manipulation by someone trying to deflect responsibility Joyster- " the impression given is that the only source of lice is from salmon farms which of course is not so."

Nice try. Salmon farms are not the only source of sea lice. But salmon farms ARE WITHOUT DOUBT the only place where the density of host species is great enough for sea lice to breed in vast enough numbers and with sufficient regularity to produce enough of them in the coastal habitat to kill salmon and sea trout smolts. You see, the sea trout is a great indicator of how salmon louse densities have exploded since salmon farming came along. If it werent for the sea trout, we would have to go to a lot more trouble to observe the changes in lice densities since the advent of salmon farming. To witness young salmon plastered in fatal loads of lice, we would have to do interceptory nettings in the deep ocean in order to catch and observe maturing young salmon close to the point of death due to excessive lice infestations.

Thanks to the fact that the sea trout doesnt go away so far from our shores and isnt away so long that it inevitably dies before returnng to tell its tail, we have seen the fatal lice infestations which didnt ever happen before salmon farms were introduced, on our sea trout. They appear in our rivers and estuaries and are caught from the shore line also. The fish we see close to death indicate that others will have perished without ever being seen.

The first summer after the installation of a salmon farm in my local bay and there were horribly infested fish in the river. They hadnt been seen before that summer, not with the amount of lice on them or the physical damage that goes with too many of the parasites. Thats how I and many others know that the excessive infestations are a result of salmon farming. My brother who isnt an angler spooned a dying louse infested sea trout from close to the river estuary with a golf club a couple of years after the farm arrived. The like of this wasnt seen prior to salmon farming. Thats because such lice infestations did not occur prior to salmon farming.

Prior to salmon farming the louse species 'Caligus elongatus' parasitised various other marine species besides salmon and sea trout such as mackerel, herring, pollack, coley (the ones I have seen them on) and still does. Let me repeat, prior to salmon farming fatal infestations of up to several hundred lice on an individual sea trout were not witnessed, therefore the factor that has changed is the presence of intensively farmed salmon. This and this alone has completely upset the balance between parasite and wild hosts. You are actually trying to aportion blame for the unnatural numbers of salmon lice in our waters on nature itself. Sorry but the huge numbers of lice being observed on sea trout since the advent of salmon farming were not seen before it so nice try for trying to blame wild non salmonidae marine host species for the sea lice explosions your industry creates.

The problematic densities of salmon louse larvae in our waters are a product of farmed fish, such numbers of lice larvae in the density and also the frequency at which they occur are only possible due to intensively farming fish in a specific location over a long period of time. If it were naturally occuring as you suggest then it would have been witnessed before salmon farming existed, but it wasn't.

i am sure the story of the lice infested sea trout in your bay is true , i have seen it myself .
the cause of course are the lice from the local salmon farm no question, however a number of questions need to be answered, 1.. the lice on the salmon would have to be at the oviderous stage to produce lots of prodgeny so why were they allowed to get to this stage? 2.... what inspections are carried out by the authorities in the area on the farms3.... were the farmers them selves doing regular louse counts.
in this part of the world we are inspected by the authorities fortnightly in the spring time and monthly thereafter, we also endever to treat our stock at the juvenile stage ,before they reproduce,and we also carry out weekly lice counts on our stock.
however, sometimes due to weather or water quality issues we may miss a scheduled treatment, if this happens we givr priority to getting this done asap.lice infestations cost us lots of lost production .
we have even gone to the trouble of moving a whole generation of fish from a bay that has a salmonid river to a bay without one after we had problems due to weather at treatment times and the smolt run was about to begin.
whilst i agree that salmon farming has its issues i believe that there is a place for a properly managed industry on the coast ,however the proposals for these super farms is daft and will definatly cause problems down the line.
lastly, the company i work for is a small independant irish owned company with sites in 5 different bays with salmonid fisheries flowing into 4 of them happily with increasing returns of salmon and sea trout into them, how many fish return is hard to know as the fisheries people will not give return figures

i am sure the story of the lice infested sea trout in your bay is true , i have seen it myself .
the cause of course are the lice from the local salmon farm no question, however a number of questions need to be answered, 1.. the lice on the salmon would have to be at the oviderous stage to produce lots of prodgeny so why were they allowed to get to this stage? 2.... what inspections are carried out by the authorities in the area on the farms3.... were the farmers them selves doing regular louse counts.
in this part of the world we are inspected by the authorities fortnightly in the spring time and monthly thereafter, we also endever to treat our stock at the juvenile stage ,before they reproduce,and we also carry out weekly lice counts on our stock.
however, sometimes due to weather or water quality issues we may miss a scheduled treatment, if this happens we givr priority to getting this done asap.lice infestations cost us lots of lost production .
we have even gone to the trouble of moving a whole generation of fish from a bay that has a salmonid river to a bay without one after we had problems due to weather at treatment times and the smolt run was about to begin.
whilst i agree that salmon farming has its issues i believe that there is a place for a properly managed industry on the coast ,however the proposals for these super farms is daft and will definatly cause problems down the line.
lastly, the company i work for is a small independant irish owned company with sites in 5 different bays with salmonid fisheries flowing into 4 of them happily with increasing returns of salmon and sea trout into them, how many fish return is hard to know as the fisheries people will not give return figures

That's not true joyster, fish counter figures are not State secrets, they are collated at local level and sent on to national level, they may not make it into annual reports but if anyone asks for them at the end of the year they will be given them. For obvious reasons counter figures are not given during the year, or on a monthly basis, as that would be useful information for poachers. If you request return figures from IFI you should get them. I'm not authorised to post them online, and I post here in a personal capacity anyway.

With regard to treatments, no one suggested your farm was not run properly - it sounds like it is run as far as possible in a way to minimise impact of sea lice. Just wondering - how often would fish be treated? i.e. for each batch of fish, how often during their life cycle would they receive chemical or in-feed treatment? And what size farm units would we be talking about?

Also, as someone with experience in the industry, do you think it would be possible to operate the proposed farm in Galway Bay - 15,000 tonnes production capacity - on an "organic" basis i.e. max of 2 treatments during the life cycle?

hi bradan,
i have requested counter returns each year for the last 3 years for the connemara fisheries by mail and phone and each time it has been refused on the grounds that the figures are for reaserch purposes only and therefore are not made available to the general public.i would be interested if this has changed.
fish are treated when levels of juvenile lice are numerous, depending on temperature this would approx every 8 weeks in summer and 3-4 months in winter.
each cage would get 2 in feed treatments inthe first 6-8 months at sea and approx 5 bath/wellboat treatments from then to harvest at 18 months . this of course varies with temp, lice levels, water quality and weather.
if the proposed farm is to be run on an organic basis, each generation on site is allowed 2 in-feed treatments ,usually slice at smolt stage, and whatever further bath /wellboat treatments that are required to harvest time , these further treatments have to be okayed by the organic certification body that the farm signs up to .
hope this helps.

Just came across this thread now and what a great debate ye are having.
I cannot add any more to the debate, on the side of no fish farms. Ye lads who are opposing the farms know yer stuff.
Joyster you're trying your best to defend the fish farming industry but it simply cannot be done.
I'm a committee member of NSFAS, No Salmon Farms at Sea, and our website is here
http://www.nosalmonfarmsatsea.com/
There is a protest on the 15th in Carrigaline, and details are on the website, aswell as a petition here
http://www.nosalmonfarmsatsea.com/how-y ... /petition/

The bottom line is these farms cannot be allowed to go ahead, especially not until they are either brought inland or technology advances.