whilst on the river on saturday a large fish topped on the far bank,it wasnt a pike that were quite active.it wasnt a chub and was too big for a roach

I have seen the odd definite barbel roll at the surface, but not many. Roll rather than splash. I would certainly not expect to see them. A rarity for me. Of course other unidentified fish could have also been barbel. I had 3 or 4 fish splash very heavily when fishing last week, and concluded that they were salmon.
Might yours also have been a game fish, or even a carp if any exist in your river? Or a bream?

my first thoughts was carp......not sure of carp numbers in the alm.ere farm stretch of the dee

But it is nicely within the salmon season, and the Dee is a salmon river. QED?

Barbel most definitely do roll mate, particularly during Summer when competition for food becomes apparent. Usually during times where insects and/or berries are falling off trees quite regularly barbel become very aggressive and as the competition becomes fierce amongst the shoalies, barbel will often try to out do each other in regards of getting to that bait/food first. It happens but, only when there is a regular supply of food and they are in that mode of competition.

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Yes they do roll and they will show quite often.

Like all Cyprinids they have to maintain their buoyancy via the swim bladder, as pressure changes and river levels go up and down they must adjust the amount of air in the swim bladder, to eject air they can “burp” air out as the swim bladder is connected to the alimentary canal via a pneumatic valve, however to gain air they must take it in, the only way cyprinids can do this is to go to the surface and gulp down a mouth full of air and force into the swim bladder via the pneumatic valve.

You might have noticed in still waters Tench and Carp will roll which will be followed moments later by a string of bubbles, this is caused as the fish takes in air, adjusts the pneumatic balance and then ejects the air it does not need.
This is often done as the fish start to feed, I suspect this buoyancy adjustment is needed because the fish are starting to be come active.

Barbel are no different, however due to an under slung mouth their roll is distinctive because you often see a fin show during the roll and it is very often followed by a small splash as the fin (I think it is a pectoral fin) hits the water, (I did have a short film of Barbel rolling in the Thames but I can’t find it at the moment).

Fish like Pike, Perch and Zander do not have a pneumatic duct they can only introduce gas to their swim bladder via their bloodstream, this gas is mainly Oxygen, which is why many of the original experiments using Oxygen were conducted once a few Perch swim bladders had been obtained (Perch swim bladders contain about 70% Oxygen, a much higher percentage of Oxygen than air which only contains 20% Oxygen.

On rivers where there is a lot of Streamer Weed (a rare sight in the south these days, Streamer Weed was plentiful in the past) you will often hear a sucking noise, this is caused by Barbel, I am not sure why they do it but it may be simply for pneumatic balance or they might be feeding on something in the weed.

In rivers where there is a lot of mud or silt on the bottom Barbel will fizz like mad as they cruise up and down, this is a dead giveaway and when you see it get your gear out.

I have often watched this happen; the fish will often cruise up and down in pairs or groups of three, passing over the same area time after time.

In this picture you can clearly see two fish side by side moving up stream.

In this picture the Barbel is getting stuck in big time.
.

Originally Posted by Zanderman

Yes they do roll and they will show quite often. Like all Cyprinids they have to maintain their buoyancy via the swim bladder, as pressure changes and river levels go up and down they must adjust the amount of air in the swim bladder, to eject air they can “burp” air out as the swim bladder is connected to the alimentary canal via a pneumatic valve, however to gain air they must take it in, the only way cyprinids can do this is to go to the surface and gulp down a mouth full of air and force into the swim bladder via the pneumatic valve. You might have noticed in still waters Tench and Carp will roll which will be followed moments later by a string of bubbles, this is caused as the fish takes in air, adjusts the pneumatic balance and then ejects the air it does not need. This is often done as the fish start to feed, I suspect this buoyancy adjustment is needed because the fish are starting to be come active. Barbel are no different, however due to an under slung mouth their roll is distinctive because you often see a fin show during the roll and it is very often followed by a small splash as the fin (I think it is a pectoral fin) hits the water, (I did have a short film of Barbel rolling in the Thames but I can’t find it at the moment). Fish like Pike, Perch and Zander do not have a pneumatic duct they can only introduce gas to their swim bladder via their bloodstream, this gas is mainly Oxygen, which is why many of the original experiments using Oxygen were conducted once a few Perch swim bladders had been obtained (Perch swim bladders contain about 70% Oxygen, a much higher percentage of Oxygen than air which only contains 20% Oxygen. On rivers where there is a lot of Streamer Weed (a rare sight in the south these days, Streamer Weed was plentiful in the past) you will often hear a sucking noise, this is caused by Barbel, I am not sure why they do it but it may be simply for pneumatic balance or they might be feeding on something in the weed. In rivers where there is a lot of mud or silt on the bottom Barbel will fizz like mad as they cruise up and down, this is a dead giveaway and when you see it get your gear out. I have often watched this happen; the fish will often cruise up and down in pairs or groups of three, passing over the same area time after time. In this picture you can clearly see two fish side by side moving up stream. In this picture the Barbel is getting stuck in big time. .

Excellent, learn something new every day and great pics.

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Just read my own post and I thought someone might ask how did I know they were Barbel, well I had one of them.



This was one of the "bubblers" she went 15lb 6oz.

I just trotted a float dowm to the head of a stream of bubbles and bingo!!

I've never seen anything more than rolling/porpoising on my home rivers. However, the Trent is another story. As well as the aforementioned rolling/porpoising, it's a regular occurrence to see barbel jump and leave the water completely.

Hi Z,

I was just about to ask questions about your interesting piece, but not about how you knew they were barbel.

You have to approach any bubbles with caution of course. Some anglers, seeing any bubbles at all, attribute them to fish. But many bubbles are simply the result of decomposition, and in a river can give the impression that their source is moving upstream, as the river moves the floating bubbles downstream. So we have to make sure a bubble stream really is from a moving source. I often watch such streams of bubbles in the shallows, and it is obvious then that no fish is involved. Make sure your bubble source really is likely to be a fish stirring up sediment and thereby releasing bubbles before casting at it.

Zanderman, are you suggesting that physostomes, fish with the swim bladder linked to the gut, can ONLY adjust their air content by that means? I thought that for micro adjustment of balance, they too can transfer oxygen from the bloodstream? Because if not, how do they cope under conditions of frozen lake surfaces? Roach/bream/carp etc.
Eels are also physostomes, and have been found with high oxygen concentrations in the swim bladder, confirming that they can use either method to change the amount of gas in their bladder. I have no data for the cyprinids.

It is a slightly weird fact (until you understand the physics involved), that to go deeper a fish needs more gas in its swim bladder, not less. I cannot help but wonder whether a main reason for a fish to take in surface air, is that it is intending to go deeper. I can only see the need for burps or swallows if a significant depth change is involved. Atmospheric changes, and non spate river level changes are surely too slow to need any gulped or burped air.

And are you sure that rolling fish are always adjusting their air balance? Or might they sometimes have other reasons to roll/jump/splash. Any fish putting its head out of the water will have to stream bubbles subsequently. Simply because the water inside its mouth will have drained out, and when submerging again it will be forced out through the gill covers.

P.S. There was coverage of barbel "sucking" at streamer weed in the angling press many years ago, and I believe the conclusion then was that the fish were feeding from the weed. Any known reasons for the loss of your Southern streamer weed?

Nice fish by the way.