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Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Well-Known Member
Sep 22, 2004
The underwater visibility varies from month to month, but does anyone know when the best time of year is in the English Channel (particularly Guernsey)?

The reason I ask is I always thought the cold water during the winter would be best, however I was in for a few hours yesterday (the sea wasn't warm!) but the vis wasn't great either. It wasn't terrible, I've had much worse in the summer, but I've had better too.
I don't spend much time in the sea in the winter, but know that during the summer the visability is fairly predictable for each month.
Are the winter months also predictible, and when is best?

Hi Boue
Vis is dependent on several factors but principally low vis is caused by particles in suspension in the water. These particals are mainly of two types and either, both or none may be present, causing the variable levels of visibility. The two types of particle are bio (plankton) and debris (mineral - rock, sand etc and detritus - weed, dead bio mass, etc.). The amount of stuff in the water is further agrivated by weather conditions, principally.sunlight, waves and swell. Debris in the water is mainly caused by heavy weather and can occur at any of year but is commonest in winter due to storms. Plankton occurs mainly in the summer and principally in two "blooms". First bloom is in late spring/early summer and is caused by increasing sunlight. Second bloom is in late summer and is a reaction to shortening days (last minute burst before winter). So here in Guernsey as in much of the atlantic vis is best in settled weather during summer (June/July/August). May and September can also be good but watch for plankton blooms. Also a summer storm in any month reduces vis. October and November are pretty good but depends on wind levels. December sees winter storms arise and through January /FebruaryMarch/April the water is devoid of plankton which can make it crystal clear if there's no heavy weather but this is rare as the water needs to settle between storms and so is normally full of debris. If you're a spearo then low vis isn't always that bad. On a summer day I've seen bass 30 feet away and watched them spot me and vanish way out of range. On other days with 10 foot vis I've seen bass suddenly appear and bang, got one. However less than 6 foot vis sees me going home.
If you want more info on current conditions Portinfers your man. He's young and keen whilst I'm old and wise. 8 degrees at the moment - you must be joking!!!!
Heh, viz.... I think best fishing is done at about 6-10ft wiz here in Mainland.. I love low viz hunts.. very exciting and more difficult to find good spots to hide in..
although for filming and camera use.. clear is good.. :) so I have both with me when I go in..

As you have very high tide might be good idea to find out the way it affects your local spot.. at me hunting grounds very low tide will ruin the viz very badly, but high is better for viz.. as long as it is not the highest of the year style tide..
Rivers affect viz quite bit, they create oily layer of sweet water on top of salty water and make it almost impossible to hunt from the surface.. but you only need to dive 2feet to get under the layer of sweet water.... this mixed water area is very good for Bass Mullet and bunch of other fish..

I find vis also affects confidence. If it's clear you can dive deeper and somehow it's just more comfortable. Fishwise it depends on what you're after. For flatfish give me crystal clear any day. Love to spot them big plaice from the surface even in 20ft which is possible in 30+ft vis. However like Pekka says bassing in 6-10ft vis can be good but bearing in mind confidence factor can be bloody depressing when there's no fish about. Two hours on your own in a 6ft square vis box is not fun and is possibly even banned under some sensory deprevation torture convension. Reefing for lobbies and conger doesn't need much vis but it helps if you can see the bottom from the surface, especially when tryng to wrinkle out a lobby or pulling that big eel out of his hole. Pain in the ass if you surface. recover, dive and find you've lost the spot as the tide orifted you off when you couldn't see the bottom.

PS Pekka, I spent a year getting my Postgrad at Exeter Uni. Went diving at Dawlish, no vis. once was enough. Went back to beach. booze and babes. Ah! sweet memories - well it was nearly 40 years ago so maybe the vis has improved.
Dave - are you a Guernsey based spearo?
You mentioned hunting for flatties. I never seem to have any luck finding them - any advice?
Hi Boue
Asking me if I am a Guernsey spearo who knows anything about flatfishing is like asking Michael Jackson if he likes little boys.
Here's a couple of tiddlers I was going to throw back last season but they had already died on my spear so I decided to take them home to make a sandwich.
I'll send you a private message with a few tips.
I wonder how many people know what a "boue" is?
Rock on!
Thanks to Dave and Pekka for the replies.

I think the current poor vis must be caused by the sudden improvement in weather we had a week or 2 ago - from snow to warm sun in a few weeks.

I agree about good vis making it difficult to get near the fish, but it's great for just exploring.
Vis was ok tonight on the north west coast(Guernsey)....
It has been calm for the last couple of days and some of the bays are clear down to 4m or more which isn't too bad - makes looking for flatfish more fun !
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