Climate change and fish stocks

[Andrew Syvret]

Off topic, but another thing I remember were the pictures of Puffins, with pipefish hanging from their beaks. The point was being made that seabirds were taking them in the absence of sandeel, but they were no use for the seabird chicks. With all the talk of pipefish now, makes me wonder if as well as sandeel numbers being low, could pipefish numbers have been unusually high? I can't rember anyone suggesting that at the time though.

 

Pipefish population explosion will not save starving seabirds

15 August 2006

 

http://www.ceh.ac.uk/news/press/pipefish.asp

 

An unexplained population explosion of snake pipefish is occurring in the seas around northern Britain. But the abundance of these fish will not prevent large numbers of puffins, terns and kittiwakes from starving to death.

 

In a paper submitted to the journal Marine Biology, an international team of scientists led by Professor Mike Harris from the Centre for Ecology & Hydrology in Banchory, reports a dramatic increase in pipefish numbers over the past few years. Pipefish were once rarely seen in British waters but are now frequently caught in trawler nets, with numbers rising 100 fold since 2002, according to some trawl surveys. Even regular divers have reported unusually large numbers along some stretches of coastline.

 

Dr Doug Beare from the European Commission’s Joint Research Centre in Italy, said that climate change is unlikely to be the primary cause of the dramatic increase. He commented, “There have been changes in water temperature in the North Sea since about 1988 but large numbers of snake pipefish have only appeared during the last three or four years. These major outbreaks of previously rare species do occasionally ‘just happen’ in marine ecosystems and they can have a startling effect on marine food webs. Interestingly, they are often associated with very poor breeding seasons in seabirds.”

 

Professor Harris said, “ Only in the last 3 years or so have snake pipefish been recorded in the diet of many species of seabird, including puffins, terns and kittiwakes breeding in colonies around UK coastlines, and in Norway, Iceland and the Faeroe Islands. 2006 seems to have been a bumper year, at least in northern Britain, and there is evidence that these birds are turning to the pipefish when their normal prey are in short supply.”

 

Breeding failures at seabird colonies off the east coast of Britain are becoming common and are thought to be due to low availability of sandeels, their usual and preferred food source. The reasons behind this reduced availability are complex but include effects due to the presence of the North Sea sandeel fishery and climate change.

 

Professor Harris is pessimistic that the availability of snake pipefish will provide an alternative source of nutrition for the birds during their breeding season. “The nutrient value of the snake pipefish is unknown but their rigid, bony structure makes them difficult for the birds to swallow. There have been numerous sightings of seabirds flying around with these fish protruding from their beaks and chicks, in particular, have great difficulty swallowing them. Many young puffins and kittiwakes have been found starving even when their nests were littered with uneaten pipefish, and tern chicks have been seen choking to death, apparently unable to regurgitate fish stuck in their throats.”

 

Most pipefish are small and live among seaweed and other marine vegetation close to the coast. The snake pipefish is much larger and can grow to more than 50cm in length and it is these fish that live in the open sea. They are normally found in Atlantic waters spreading from Norway and Iceland in the north to the Azores in the south and eastwards to the Baltic. Close relatives of the seahorse, pipefish are long and thin with segmented and usually hard, armour-cased bodies. Like the seahorse, it is the male that cares for the developing eggs, keeping them in a brood pouch or attached to the underside of his body.

[Jaffa]

Thank you, i have looked at Johns web site several times now and personally i am more happy with his comments than others. Although e527 is not one of those 'super trawlers' it does put it in perspective the problems within the fishing industry. I would again personally prefer to let the cod or whiting eat the sand eel than let it be processed in to a fish food pellet. I am aware that the sand eel can sometimes be very abundant but also it does not take a lot of effort or some thing to happen natually to make it a serious problem.

 

regards barry

 

Hi Barry,

 

Although e527 is not one of those 'super trawlers' it does put it in perspective the problems within the fishing industry.

What do you mean by that?

 

I would again personally prefer to let the cod or whiting eat the sand eel than let it be processed in to a fish food pellet.

 

Fair enough. care to expand ob why you think that way?

 

I am aware that the sand eel can sometimes be very abundant but also it does not take a lot of effort or some thing to happen natually to make it a serious problem.

 

A serious problem in what way?

 

Chris

[Jaffa]

Hi Andrew,

 

Thanks for the link

 

 

I've seen this stuff on pipefish lately and thats what makes me wonder about conditions back then. I suppose there is unlikely to be a connection, but you never know i guess.

 

I was diving day in day out then, and don't remember big shoals of pipefish; othh, in the areas i was, i never saw that many big shoals of sandeel either !

[barry luxton]

Hi Barry,

What do you mean by that?

Fair enough. care to expand ob why you think that way?

A serious problem in what way?

 

Chris

 

Hi Chris, I hope i can answer your questions without causing irritation. The picture of the trawler in port on John's web site is not pretty when you consider that it is only harvesting a crop. To me it shows that the fish are there so go and get as many as possible, short of sinking the ship. Every one has to earn a living but that cannot be right. Another concern is the method of fishing for them with masses of very fine mesh where it cannot discriminate between sand eel or juvenile fish, i wonder what the amount of bycatch there could be.

 

I am sure that there must be a better way to feed farmed salmon or fish in your pond for example than to catch, process the sand eel into fish food. Or to use it as oil as a supplement in power stations. If i had the choice i would much rather see the sand eel staying in the natural food chain hopefully giving say the cod stocks a chance to grow.

 

I am aware that the sand eel fishery is on a knife edge. It only requires a hiccup and the consequence of the fishery dissapearing is not very good for all concerned. I am aware of say the greens crying out that the eel stocks has been decimated by trawling to discover that there was possibly a natural occurance, they bred late, lack of food for them or whatever. Equally, It is now possible for the trawlers to take the quota in less than two weeks. If they was to do that and along with say another period of natural occurance it leaves the stock of sand eel below sustainable level and so the cycle starts again. To me its not management but desperate measures all the time. This year the trawlers are doing thier job when all of a sudden someone said, sorry we made a mistake, the figures are wrong and there isn't the amount of eel that we first thought, stop fishing. I do not think its the seas warming for the eel to move north or to bu............er off from the uk waters alltogether as the stock up in scotland are based on a three year cycle where the southern ones are on two. The eel is showing that it can adapt to change.

 

cheers barry

[Jaffa]

The picture of the trawler in port on John's web site is not pretty when you consider that it is only harvesting a crop. To me it shows that the fish are there so go and get as many as possible, short of sinking the ship.

Thats a skippers job surely? What it looks like is irrelevant surely? Would two ships "looking normal" but landing the same total be different?

 

Every one has to earn a living but that cannot be right. Another concern is the method of fishing for them with masses of very fine mesh where it cannot discriminate between sand eel or juvenile fish, i wonder what the amount of bycatch there could be.

 

The trouble with that is that the scientific surveys show just the opposite. While "common sense" says they MUST take a lot of bycatch, the surveys show the sandeel boats take extraordinary little. No idea why that is the case, but until someone shows me science thats says otherwise then I'll go with that.

 

 

 

I am sure that there must be a better way to feed farmed salmon or fish in your pond for example than to catch, process the sand eel into fish food. Or to use it as oil as a supplement in power stations. If i had the choice i would much rather see the sand eel staying in the natural food chain hopefully giving say the cod stocks a chance to grow.

Interesting choice of examples Aquaculture feed, then fair enough its something to discuss. The power station stuff is often mentioned but no one seems to know just what, where and when that is all about.

 

FWIW im an optimist who believes that new feeds will be developed for aquaculture. It'll make no real difference to the the demand for fishmeal/oil though ; the stuffs just so useful another market will step in.

 

 

 

I am aware that the sand eel fishery is on a knife edge. It only requires a hiccup and the consequence of the fishery dissapearing is not very good for all concerned. I am aware of say the greens crying out that the eel stocks has been decimated by trawling to discover that there was possibly a natural occurance, they bred late, lack of food for them or whatever. Equally, It is now possible for the trawlers to take the quota in less than two weeks. If they was to do that and along with say another period of natural occurance it leaves the stock of sand eel below sustainable level and so the cycle starts again. To me its not management but desperate measures all the time. This year the trawlers are doing thier job when all of a sudden someone said, sorry we made a mistake, the figures are wrong and there isn't the amount of eel that we first thought, stop fishing. I do not think its the seas warming for the eel to move north or to bu............er off from the uk waters alltogether as the stock up in scotland are based on a three year cycle where the southern ones are on two. The eel is showing that it can adapt to change.

 

A lot in that paragraph. Forgive me for retreating to me bed for now;)

 

Chris

[Jaffa]

I am aware that the sand eel fishery is on a knife edge. It only requires a hiccup and the consequence of the fishery dissapearing is not very good for all concerned. I am aware of say the greens crying out that the eel stocks has been decimated by trawling to discover that there was possibly a natural occurance, they bred late, lack of food for them or whatever. Equally, It is now possible for the trawlers to take the quota in less than two weeks. If they was to do that and along with say another period of natural occurance it leaves the stock of sand eel below sustainable level and so the cycle starts again. To me its not management but desperate measures all the time. This year the trawlers are doing thier job when all of a sudden someone said, sorry we made a mistake, the figures are wrong and there isn't the amount of eel that we first thought, stop fishing. I do not think its the seas warming for the eel to move north or to bu............er off from the uk waters alltogether as the stock up in scotland are based on a three year cycle where the southern ones are on two. The eel is showing that it can adapt to change.

 

Hi Barry,

 

I don't see how sandeel stocks are on any sort of a "knife edge" . Yes they have collapsed (from the point of view of a sandeel fisher or sandeel predator) but that could be a perfectly natural thing to happen. They are tightly coupled into what is happening with the plankton, and small changes that results in the plankton being the wrong kind, slightly early or late is going to have a massive effect on their numbers.

 

Global warming? well maybe , "overfishing" no way i can see that possible.

 

I picture such a species as being well adapted already to "crisis management" regardless of the abilities of our fisheries scientists, or the whims of mother nature. The danish fleet might well be tied up, cod may starve, but if its a perfect year for the sandeel next year, then they could be back with a "historical record" of a population size.

 

I take it that the idea the fishing fleet could catch its quota in two weeks was taken from the small Firth of Forth fishery? Or are you saying that in the principal fishery the Danish fleet can catch several hundred thousand tonnes of sandeel in 2 weeks?

 

I don't believe that for one minute, though am happy to be corrected if im wrong. Even then I can't for the life of me see what difference that makes to the number of sandeel the next year, compared to the environmental factors.

 

 

So what would be considered a "sustainable level" for the central north sea sandeel stock? As you point out the different sandeel stocks have different life histories, (though i'm not aware of it being a "north/south" thing ?), presumably reflecting past events , but the main fishery; the one that creates all the news can breed at under a year old. Wonder why that is?

 

Chris

[barry luxton]

Hi Barry,

 

I don't see how sandeel stocks are on any sort of a "knife edge" . Yes they have collapsed (from the point of view of a sandeel fisher or sandeel predator) but that could be a perfectly natural thing to happen. They are tightly coupled into what is happening with the plankton, and small changes that results in the plankton being the wrong kind, slightly early or late is going to have a massive effect on their numbers.

 

Global warming? well maybe , "overfishing" no way i can see that possible.

 

I picture such a species as being well adapted already to "crisis management" regardless of the abilities of our fisheries scientists, or the whims of mother nature. The danish fleet might well be tied up, cod may starve, but if its a perfect year for the sandeel next year, then they could be back with a "historical record" of a population size.

 

I take it that the idea the fishing fleet could catch its quota in two weeks was taken from the small Firth of Forth fishery? Or are you saying that in the principal fishery the Danish fleet can catch several hundred thousand tonnes of sandeel in 2 weeks?

 

I don't believe that for one minute, though am happy to be corrected if im wrong. Even then I can't for the life of me see what difference that makes to the number of sandeel the next year, compared to the environmental factors.

So what would be considered a "sustainable level" for the central north sea sandeel stock? As you point out the different sandeel stocks have different life histories, (though i'm not aware of it being a "north/south" thing ?), presumably reflecting past events , but the main fishery; the one that creates all the news can breed at under a year old. Wonder why that is?

 

Chris

Hi Chris, sorry i have taken so long to reply. Your first paragrath is agreeing with me, thank you when you say they have collapsed and i say knife edge. Its all the same, on minute there here, the next disappeared for what ever reason. I agree with you when you say that they have a short cycle, from one year......... It again would be nice to try and see if they could stay on the ground a little longer as they could live for eight years. I would be good if it would be possible to target seven-eight year old eels as apposed to one year old, would it not.

 

Why do you have a thing about overfishing? I have seen quote's that one of the fleets had taken thier quota in two weeks , it was on this web site, still looking for it. I do believe it was the danish fleet. So, you must agree that the eu has the capability to catch all of the sandeel stocks with relative ease, again there is the possibility that they could be overfished. I think that there must allways be a safty factor regarding the amount of sandeel stock to buffer against all eventualities man made or not. I think that applys to all fish stocks.

 

Cheers Chris, regards barry

[Jaffa]

Hi Chris, sorry i have taken so long to reply. Your first paragrath is agreeing with me, thank you when you say they have collapsed and i say knife edge. Its all the same, on minute there here, the next disappeared for what ever reason. I agree with you when you say that they have a short cycle, from one year......... It again would be nice to try and see if they could stay on the ground a little longer as they could live for eight years. I would be good if it would be possible to target seven-eight year old eels as apposed to one year old, would it not.

 

Why do you have a thing about overfishing? I have seen quote's that one of the fleets had taken thier quota in two weeks , it was on this web site, still looking for it. I do believe it was the danish fleet. So, you must agree that the eu has the capability to catch all of the sandeel stocks with relative ease, again there is the possibility that they could be overfished. I think that there must allways be a safty factor regarding the amount of sandeel stock to buffer against all eventualities man made or not. I think that applys to all fish stocks.

 

Cheers Chris, regards barry

 

Hi Barry,

 

I think the two week quote was the Firth of Forth example, which yes might have been the Danes but as i understand it is a side issue compared with the main stocks in the central north sea.

 

I could believe the central North sea fishery QUOTA could be fished out with "relative ease" but as for your suggestion that

 

So, you must agree that the eu has the capability to catch all of the sandeel stocks with relative ease,

 

sorry but I just dont accept or understand where that comes from?

 

You reckon there should be a "safety" factor, and lump in all fish stocks as one. Sorry m8, but that seems wrong headed from my experience/understanding.

 

I can understand how the big predators could be wiped out by fishing, I can even understand how cod may be among those. I cannot see how the same is true of many of the short lived plankton eaters.

 

What would be your "safety level" for the sandeel fishery btw?

 

The UK commercials, along with the greens, RSA's, uncle tom cobbly and all, have attacked the danish for the past couple of decades. Screeds of internet hate is directed towards it; yet when you look for evidence, or ask on a forum like this, there is little.

 

Change my mind - show me the evidence

 

Chris

[Jaffa]

Why do you have a thing about overfishing?

 

I worked for the fishery office in Aberdeen just as quotas were first introduced and watched the first steps into the Aliceinwonderland world it all became.

 

Later worked in aquaculture and saw aliceinwonderland part 2.

 

I dislike lies and spin, and knowing good people went down the drain on the back of them. Very sick of the manipulation that the environmental groups are managing to pull. Worry about my kids future.

 

and i just want to know whats going on!

[Jim Roper]

"It also added that although cold-water species had moved further north in some regions, such as the North Sea, the shifts had not happened elsewhere."

 

Still something to be had off Chesil though!

 

 

Edited December 19, 2006 by Jim Roper