The reproductive bits of this fucus, as comparison with previous picture.
No interactions present.
Yes Ben, pretty certain. One of the very few correctly identified in iSpot. But not an easy picture and may yet be a hybrid. You have mentioned a previous picture - where is it?
this is not a picture of the reproductive parts (receptacles) but of the frond edges which are inflated with gas (but not called bladders).
See my two posts http://www.ispotnature.org/node/688049 and http://www.ispotnature.org/node/690270
Lat/Lng: 54.16857, -2.83348
OS grid ref: SD456750
Abundant along the shoreline.