Figure 1
Sampling locations of Ponto-Caspian gammarids in the Vistula estuary: the Vistula Lagoon (VL) and the Vistula Delta (VD)
Table 1
Descriptive statistics of body length (L) and wet weight (W) of gammarid species from the Vistula Lagoon and the Vistula Delta in 2009–2011
| Species | N | % | L (mm) ± SD | W (g) ± SD |
|---|---|---|---|---|
| P. robustoides | 374 | 24 | 8.55 ± 4.02 | 0.019 ± 0.047 |
| O. crassus | 617 | 41 | 5.93 ± 1.82 | 0.003 ± 0.004 |
| D. haemobaphes | 530 | 35 | 7.73 ± 2.65 | 0.012 ± 0.011 |
Figure 2
Length–frequency distribution of Ponto-Caspian gammarids in the Vistula estuary in warm months of 2009–2011
Figure 3
Relationship between total length and wet weight of Ponto-Caspian gammarids in the Vistula estuary in warm months of 2009–2011
Table 2
Calculated intercepts (a) and slopes (b) in the total length–wet weight relationship regression models y = axb of gammarids from different areas and for different numbers of individuals (n)
| Species | Area of occurrence | intercepts (a) | slopes (b) | individuals (n) | Reference |
|---|---|---|---|---|---|
| Pontogammarus robustoides | Vistula Lagoon and Delta Europe: Poland (brackish environment) | 0.0107 | 3.1317 | 374 | current study |
| Obesogammarus crassus | 0.0041 | 3.5461 | 617 | ||
| Dikerogammarus haemobaphes | 0.141 | 2.0896 | 530 | ||
| Pontogammarus robustoides | Gulf of Gdańsk Europe: Poland (brackish environment) | 0.0367 | 2.852 | 72 | Dobrzycka-Krahel et al. 2016 |
| Obesogammarus crassus Dikerogamarus haemobaphes | 0.0069 | 3.3477 | 75 | ||
| Dikerogammarus villosus | 0.0033 | 3.7855 | 225 | ||
| 0.0674 | 2.852 | 117 | |||
| Gammarus sp. | Black Sea (brackish environment) | 0.0016 | 2.87 | 20 | Rosati et al. 2012 |
| Gammarus minus | North America (freshwater environment) | 0.012 | 2.74 | Basset & Glazier 1995 | |
| Gammarus pseudolimnaeus | 0.0049 | 3.001 | 37 | Marchant & Hynes 1981 | |
| Gammaridae | Mediterranean (transiti onal and waters) Black Sea | 0.0046 | 1.2 | 20 | Rosati et al. 2012 |