
Species profile
bladder wrack
Fucus vesiculosus
Identify bladder wrack (Fucus vesiculosus) from a photo: try it free in your browser, or get unlimited IDs, no sign-up, with the CatchRules app. Plus current fishing rules across 1 jurisdiction.
At a glance
bladder wrack (Fucus vesiculosus) is a marine alga with specific harvest rules tracked in 1 of 66 jurisdictions covered by CatchRules.
Confirmed by 2,460 research-grade iNaturalist observations, with Maine, Massachusetts, and Nova Scotia the top jurisdictions by observation count.
Notable details
- Named for the paired air-filled bladders along its fronds that keep photosynthetic tissue near the surface.
- Can grow to about 90 cm (3 feet) in length in the North Atlantic.
- Contains high levels of iodine and was historically harvested as a nutritional supplement and fertilizer.
- Periwinkles and other shore snails graze heavily on it, making it a keystone intertidal food source.
- The air bladders keep fronds upright in the water column, maximizing light exposure for photosynthesis.
Where bladder wrack are seen
Jurisdictions with rules for bladder wrack
Background
Fucus vesiculosus, known by the common name bladder wrack or bladderwrack, is a seaweed found on the coasts of the North Sea, the western Baltic Sea, and the Atlantic and Pacific Oceans, also known by the common names black tang, rockweed, bladder fucus, sea oak, black tany, cut weed, dyers fucus, red fucus, and rock wrack. It was the original source of iodine, discovered in 1811, and was used…
Background excerpt adapted from Wikipedia's bladder wrack article (CC BY-SA). Visit Wikipedia for the full entry.
Other brown algae/kelps on CatchRules
Frequently asked questions
What is bladder wrack?
bladder wrack (Fucus vesiculosus) is a marine alga with specific harvest rules tracked in 1 of 66 jurisdictions covered by CatchRules.
What is the scientific name for bladder wrack?
bladder wrack is Fucus vesiculosus.
Is bladder wrack regulated for fishing?
Yes — bladder wrack has fishing regulations in 1 U.S. state and/or Canadian province tracked by CatchRules. See the "Jurisdictions with rules" section above for the binding-source links.
How can I identify bladder wrack?
Take a photo with the free CatchRules app for iPhone or Android — on-device identification recognizes bladder wrack along with ~1,500 other species. No sign-up, unlimited use.
Photo credit: iNaturalist / Wikipedia. Identification reference only — verify regulations with the issuing wildlife agency before retaining a catch.