Taxonomy
Balanus improvisus
Distribution
Status
Legal status
Third Schedule listed species under Regulations 49 & 50 in the European Communities (Birds and Natural Habitats) Regulations 2011. (Note: Regulation 50 not yet enacted).
Native status
Non-native
First reported in the wild
Pre-1950
Invasiveness
Invasive species - risk of Medium Impact
Irish status
Established
Introduction pathways - 1
Transport Stowaway
Introduction pathways subclass - 1
Ship/boat hull fouling
Invasive score
15
NAPRA Ireland risk assessed
No
Species Biology
Identification
White sessile crustacean, up to 20mm in diameter. Barnacles are difficult to identify to species without specialist knowledge, though a key to identifying non-native barnacles is available from the European Network on Alien Invasive Species -
Ecology
Fouling organism on boats and piers it displaces native barnacle species.
Habitat
Marine
Reproduction
Hermaphrodites and facultative self fertilisers, releasing free swimming nauplial larvae into the water (Olenin, 2006).
Pathway and vector description
Introduced as a fouling organism on boats and ships (Minchin, 2009).
Mechanism of impact
Competition
Broad environment
Marine
Habitat description
Attaches to rocks and other hard substrates.
Species group
Invertebrate
Distribution
World distribution(GBIF)
Irish distribution
Established - Localised (Minchin, 2009).
Native distribution
Most likely native to North America (Olenin, 2006).
Temporal change
Date of first record category
Pre-1900
Fifty year date category
1901-1950
Records submitted to Data Centre in 2024
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Further information
Delivering Alien Invasive Species In Europe (DAISIE) project list this as one of the 100 Worst Invaders in Europe.
References
Publications
Olenin, S. (2006) DAISIE Factsheet - Balanus improvisus Darwin, 1854. Minchin, D. (2009). A checklist of alien and cryptogenic aquatic species in Ireland. Aquatic Invasions, 2(4), 341-366.