| Main Ref. | Bartley, D.M. (comp./ed.), 2006 |
| To | Denmark |
| FAO area | Atlantic, Northeast |
| From | unknown |
| FAO area | |
| Year | |
| Range | 1920 - 1929 |
| Period | 1900-1924 |
| Established in the Wild | yes, self reproducing |
| Established in Aquaculture | |
| Significant Ecological Interactions | unknown |
| Significant Socio-economic Effects | |
| Introduced by | unknown |
| Reason | accidental |
| Other Reason | |
| Comments | See also Lassen, 1975. |