Another 4 Seaweeds for ID

[jdoherty]

I took all of these photos along the coast of Norther Ireland. I'd once again appreciate any help with IDs.

Thanks, John.

[ladyhawk]

Bladder wrack (Fucus vesiculosus ) Toothed wrack ( Fucus serratus) Spiral wrack (Fucus spiralis) Horned wrack (Fucus ceranoides)

have never seen Horned wrack myself but will be keeping my eyes open for it now hope this helps.

[RobSutton]

I think the first three are all Bladder Wrack (Fucus vesiculosus) and the last is Channel Wrack (Pelvetia canaliculata)

[jdoherty]

Quite a difference in opinion but that's to be expected. Has anyone else any ideas or support for the above suggestions.

John

[zan]

hiya,

The first is Fucus vesiculosus, as it has paired gas bladders along the fronds which is characteristic. I'm not sure about 2 - it MIGHT be Fucus ceranoides or Fucus spiralis (spiralis tends to have gently spiralling fronds, but it's not always clear unless they are hanging free) but I wouldn't put money on it. There's also a possibilty that 2 species have produced a hybrid, which is not uncommon.

3 is also probably F. vesiculosus as RS says. It's definitely not Fucus serratus as the fronds of that species are very obviously serrated and jagged.

The last one is definitely Pelvetia canaliculata as RobSutton says - the thin fronds with no gas baldders, small size and deep channel (canal) running up the middle of the fronds is very characteristic.

[RobSutton]

I think number two also seems to have air bladders (unless they are perfectly bladder shaped flat periwinkles) and I'm pretty sure that neither Fucus ceranoides or Fucus spiralis have bladders. The ones I find confusing are specimens of vesiculosus that don't have air bladders at all and this seems to be a specimen with rather fewer bladders than normal but to me it still looks like vesiculosus.

[zan]

Aye, true enough - it's hard to tell without seeing the whole thing! I agree those are air bladders though, so you're probably right about it being Fv, especially if you can get specimens with very few \ no bladders.

[jdoherty]

Pic 2 does have air bladders but there is also a flat periwinkle in the lower centre of the photo. I did think pics 1 and 2 did look odd when I noticed them. The bladders looked somewhat different from any other bladder wrack pics that I have taken. Hence I've posted them here.

Thanks for providing IDs and such interesting information.

John