Plant
Wakame
Undaria pinnatifidaAlso known as Asian Kelp, Japanese Kelp, Sea Mustard, Miyeok
Wakame is a fast-growing annual kelp recognized by its broad, lobed golden-brown fronds supported by a prominent central midrib and ruffled spiral sporophylls near the base. Native to cold, sheltered reefs of the northwest Pacific, it thrives in high-nutrient marine environments where it can grow several centimeters per day in late winter. Efficient dispersal via microscopic swimming zoospores and hull fouling has enabled it to aggressively colonize temperate harbors and natural reefs worldwide.
MarineInvasiveMacroalgae
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Diet & preySunlight, Dissolved Nitrates, Phosphates
Predators
- Sea Urchins
- Abalone
- Herbivorous Fish
ThreatsMarine heatwaves, extreme water temperatures, and native canopy competition
HabitatsTemperate rocky reefs, artificial harbor structures, marinas, and aquaculture ropes
Life span1 year (annual life cycle)
Classification
- OrderLaminariales
- FamilyAlariaceae
- GenusUndaria
- SpeciesUndaria pinnatifida
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Safe to observe at a normal distance.
Responsible observation
- Subtidal Identification: Look for a distinctive raised midrib running through the center of a wavy, lobed frond.
- Biosecurity Practice: Thoroughly wash and dry diving gear and boat hulls to prevent spreading motile spores.
- Seasonal Timing: Search shallow docks and rocky shores in early spring when sporophytes reach maximum size.
Competitor "Giant kelp (Macrocystis pyrifera), Monterey Bay aquarium, California" by LT&C is licensed under CC BY 2.0. To view a copy of this license, visit https://creativecommons.org/licenses/by/2.0/. · cc-by
Competitor "Bull kelp.(Nereocystis luetkeana)" by Bernard Spragg is marked with CC0 1.0. To view the terms, visit https://creativecommons.org/publicdomain/zero/1.0/. · cc0
Neighbor (c) Cwmhiraeth, some rights reserved (CC BY-SA) · cc-by-sa
Predator no rights reserved, uploaded by Braden J. Judson · cc0
Same Family (c) Thor-Rune Hansen, some rights reserved (CC BY-SA), uploaded by Thor-Rune Hansen · cc-by-sa
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Found in Collections
Ecosystem chain
Wetland Territory
Wakame is found in this collection. Identify it in Fauna to fill this slot and continue your progress.
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