Cygnus atratus
System : Freshwater_terrestrial
Kingdom
Phylum
Class
Order
Family
Animalia
Chordata
Aves
Anseriformes
Anatidae
  • Not Evaluated
    NE
  • No Alien Population
    NA
  • Data Deficient
    DD
  • Minimal Concern
    MC
  • Minor
    MN
  • Moderate
    MO
  • Major
    MR
  • Massive
    MV
  • General
  • Distribution
  • Impact
  • Management
  • Bibliography
  • Contact
Common name
 
Synonym
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Summary

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Compiler:

Review:

Publication date:

Recommended citation: Global Invasive Species Database (2025) Species profile: Cygnus atratus. Downloaded from http://iucngisd.org/gisd/speciesname/Cygnus+atratus on 05-02-2025.

Countries (or multi-country features) with distribution records for Cygnus atratus
ALIEN RANGE
NATIVE RANGE
Informations on Cygnus atratus has been recorded for the following locations. Click on the name for additional informations.
Lorem Ipsum
Location Status Invasiveness Occurrence Source
Details of Cygnus atratus in information
Status
Invasiveness
Arrival date
Occurrence
Source
Introduction
Species notes for this location
Location note
Management notes for this location
Impact
Mechanism:
Outcome:
Ecosystem services:
Impact information
Red List assessed species 1: LC = 1;
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Management information
Bibliography
0 references found for Cygnus atratus

Management information
Contact
The following 0 contacts offer information an advice on Cygnus atratus
MO
Cygnus atratus
Date assessed
2021-10-04
Year published
2022
Eicat category
MO (Moderate)
Justification for EICAT assessment


In New Zealand the Black Swan is the only large grazer of intertidal seagrass. At sites of intense grazing (annual removal of 19-20% of the average seagrass biomass), substantial decline (43-69%) in plant biomass in the subsequent growing season was observed (Zostera muelleri) (Dos Santos et al. 2012).
Confidence rating
High
Mechanism(s) of maximum impact
Grazing/herbivory/browsing
Countries of most severe impact
New Zealand
Description of impacts
The Black Swan feeds on native plant species, causing the decline of a native seagrass in New Zealand. It also hybridizes with native swan species.
Assessor
Thomas Evans; Tom Allmert
Contributors
Reviewers
EICAT authority
Recommended citation
Thomas Evans, Tom Allmert (2025). Cygnus atratus. IUCN Environmental Impact Classification for Alien Taxa (EICAT).