| Years | Season | Max. density (ind∙l−1) | Temp. (˚C) | Salinity (psu) | Chla (µg∙l−1) |
| 1989-1992 | Spring | 32.0 ± 30.3 | 18.4 ± 3.6 | 23.0 ± 2.6 | 19.3 ± 2.5 |
| 1993-2002 | Spring | 319.1 ± 260.0 | 13.8 ± 3.9 | 22.0 ± 1.8 | 17.9 ± 8.0 |
| 2003-2009 | Spring | 56.7 ± 38.6 | 13.4 ± 3.4 | 22.8 ± 1.6 | 7.9 ± 6.5 |
| 1989-1992 | Autumn | 11.0 | 14.3 | 25.9 | 17.0 |
| 1993-2002 | Autumn | 46.2 ± 35.6 | 15.3 ± 1.7 | 24.7 ± 1.9 | 31.8 ± 39.4 |
| 2003-2009 | Autumn | 37.5 ± 35.8 | 16.9 ± 1.7 | 24.3 ± 1.5 | 11.8 ± 11.5 |