Table 2.
Mean (individuals m–2 with standard error) abundance of mesozooplankton taxa; evenness (J); diversity (H’, Shannon index); total mesozooplankton abundance (103 individuals m–2); total mesozooplankton biomass (mg dry mass m–2); environmental parameters (Temp—mean temperature, °C; Sal—mean salinity; Chla—mean chlorophyll a concentration, mg m–3) in each group defined by cluster analysis and results of comparisons between groups (simple ANOVA or Kruskal–Wallis Test).
| Taxon/Parameter | Trophic Status | Biogeography | Cluster 1 | Cluster 2 | ANOVA or Kruskall–Wallis Test (p-Level) |
|---|---|---|---|---|---|
| Copepoda | 49,086 ± 14,379 | 118,331 ± 32,689 | <0.05 | ||
| Calanus finmarchicus (Gunner, 1765) | He | Bor | 2472 ± 567 | 3243 ± 1225 | 0.581 |
| Calanus glacialis Jaschnov, 1955 | He | Ar | 1925 ± 430 | 5396 ± 1485 | <0.05 |
| Calanus hyperboreus Krøyer, 1838 | He | Ar | 6 ± 5 | 2400 ± 1518 | <0.05 |
| Centropages hamatus (Lilljeborg, 1853) | Om | Bor-Ar | 34 ± 24 | 14 ± 10 | 0.818 |
| Copepoda ova | Bor/Bor-Ar | 13,315 ± 2602 | 8308 ± 1234 | 0.113 | |
| Copepoda nauplii | Om | Bor/Bor-Ar | 13,263 ± 4304 | 27,933 ± 8075 | 0.140 |
| Gaetanus tenuispinu (Sars G.O., 1900) | Om | Ar | 14 ± 11 | 6 ± 4 | 0.937 |
| Metridia longa (Lubbock, 1854) | Om | Ar | 122 ± 52 | 7039 ± 5037 | <0.05 |
| Microcalanus pusillus Sars G.O., 1903 | Om | Bor-Ar | 312 ± 111 | 1473 ± 282 | <0.05 |
| Microcalanus pygmaeus (Sars G.O., 1900) | Om | Ar | 5433 ± 2239 | 22,941 ± 2287 | <0.001 |
| Microsetella norvegica (Boeck, 1865) | Om | Cs | 20 ± 9 | 9 ± 9 | 0.485 |
| Oithona atlantica Farran, 1908 | Om | Bor | 31 ± 15 | 239 ± 90 | 0.093 |
| Oithona similis Claus, 1866 | Om | Cs | 11,884 ± 3925 | 33,218 ± 8691 | 0.132 |
| Triconia borealis (Sars G.O., 1918) | Om | Cs | - | 67 ± 48 | na |
| Parathalestris croni (Krøyer, 1842) | Om | Bor-Ar | 3 ± 3 | 5 ± 5 | 0.937 |
| Pseudocalanus spp. I–IV | He | Bor-Ar | 33 ± 33 | 3933 ± 1991 | <0.05 |
| Pseudocalanus minutus (Krøyer, 1845) V–VI | He | Bor-Ar | 152 ± 32 | 1767 ± 626 | <0.05 |
| Pseudocalanus acuspes (Giesbrecht, 1881) V–VI | He | Bor-Ar | 67 ± 17 | 332 ± 64 | <0.05 |
| Scolecithricella minor (Brady, 1883) | Om | Bor-Ar | - | 8 ± 8 | na |
| Medusae | 8 ± 5 | 31 ± 12 | 0.562 | ||
| Aeginopsis laurentii Brandt, 1838 | Cr | Ar | - | 2 ± 2 | na |
| Aglantha digitale (Müller, 1776) | Cr | Bor | - | 6 ± 3 | na |
| Euphysa flammea (Linko, 1905) | Cr | Bor | 5 ± 3 | 9 ± 3 | 0.341 |
| Euphysa spp. juv. | Cr | Bor | 3 ± 2 | 14 ± 4 | <0.05 |
| Meroplanktonic larvae | |||||
| Cirripedia cypris larvae | Om | Mx | 23 ± 23 | - | na |
| Cirripedia nauplii | Om | Mx | 1332 ± 318 | 19,872 ± 10820 | 0.394 |
| Echinoidea (echinopluteus larvae) | Om | Mx | 432 ± 263 | 524 ± 213 | 0.793 |
| Gastropoda larvae | Om | Mx | - | 236 ± 67 | na |
| Ophiuroidea (ophiopluteus larvae) | Om | Mx | 53 ± 30 | 395 ± 161 | 0.180 |
| Polychaeta larvae | Om | Mx | 1648 ± 484 | 5108 ± 1884 | 0.106 |
| Chionoecetes opilio (Fabricius, 1788) larvae | Om | Bor-Ar | 17 ± 8 | 237 ± 106 | <0.05 |
| Pagurus spp. zoea | Om | Bor-Ar | 14 ± 12 | 2 ± 2 | 0.589 |
| Lithodes maja (Linnaeus, 1758) zoea | Om | Bor-Ar | - | 2 ± 2 | na |
| Sabinea spp. larvae | Om | Bor-Ar | - | 2 ± 2 | na |
| Eualus gaimardi (H. Milne-Edwards, 1837) larvae | Om | Bor-Ar | - | 2 ± 2 | na |
| Euphausiids | 19,802 ± 6908 | 3072 ± 947 | <0.05 | ||
| Meganyctyphanes norvegica (M. Sars, 1857) | He | Bor | - | 2 ± 2 | na |
| Thysanoessa inermis (Krøyer, 1846) | He | Bor | 5 ± 2 | 2 ± 2 | 0.394 |
| Thyssanoessa raschii (M. Sars, 1864) | He | Bor-Ar | 2 ± 2 | 5 ± 3 | 0.589 |
| Thyssanoessa spp. calyptopis | He | Bor-Ar | 636 ± 582 | 40 ± 23 | 0.589 |
| Thyssanoessa spp. nauplii | He | Bor-Ar | 19,159 ± 6322 | 3023 ± 917 | <0.05 |
| Hyperiids | 2 ± 2 | 64 ± 41 | <0.05 | ||
| Themisto abyssorum Boeck, 1870 | Cr | Bor | - | 19 ± 10 | na |
| Themisto libellula Lichtenstein, 1822 | Cr | Ar | - | 36 ± 25 | na |
| Themisto juv. | Cr | 2 ± 2 | 9 ± 6 | 0.589 | |
| Appendicularia | 329 ± 237 | 23,505 ± 7342 | <0.05 | ||
| Fritillaria borealis Lohmann, 1896 | Om | Bor-Ar | 274 ± 182 | 21,050 ± 5987 | <0.05 |
| Oikopleura juv. | Om | Bor-Ar | 33 ± 33 | 2345 ± 1317 | <0.05 |
| Oikopleura vanhoeffeni Lohmann, 1896 | Om | Bor-Ar | 22 ± 22 | 110 ± 38 | 0.069 |
| Ctenophora | 5 ± 3 | 16 ± 10 | 0.634 | ||
| Beroe cucumis Fabricius, 1780 | Cr | Bor-Ar | - | 5 ± 3 | na |
| Mertensia ovum (Fabricius, 1780) | Cr | Ar | 5 ± 3 | 11 ± 7 | 0.699 |
| Others | 120 ± 61 | 60 ± 34 | 0.387 | ||
| Boroecia borealis (Sars, 1866) | Om | 12 ± 12 | - | na | |
| Clione limacina (Phipps, 1774) larvae | Cr | Bor-Ar | - | 3 ± 3 | na |
| Limacina helicina Phipps, 1774 larvae | He | Bor-Ar | - | 8 ± 8 | na |
| Limacina helicina Phipps, 1774 | He | Bor-Ar | 33 ± 19 | 22 ± 9 | 0.616 |
| Parasagitta elegans (Verrill, 1873) | Cr | Bor-Ar | 73 ± 28 | 25 ± 12 | 0.240 |
| Tomopteris spp. | He | Bor | 2 ± 2 | - | na |
| Pisces larvae | Cr | Mx | - | 2 ± 2 | na |
| Parameters | |||||
| Total abundance | 73 ± 14 | 171 ± 24 | <0.05 | ||
| Total biomass | 846 ± 179 | 2935 ± 1358 | <0.05 | ||
| J’ | 0.6 ± 0.02 | 0.64 ± 0.01 | 0.202 | ||
| H’(loge) | 1.85 ± 0.05 | 2.17 ± 0.03 | <0.001 | ||
| H’(log2) | 2.67 ± 0.07 | 3.13 ± 0.05 | <0.001 | ||
| Temp | 0.89 ± 0.27 | 0.22 ± 0.13 | <0.05 | ||
| Sal | 34.70 ± 0.02 | 34.81 ± 0.03 | <0.05 | ||
| Chla | 2.41 ± 0.49 | 1.21 ± 0.20 | <0.05 |
Note. na—no analysis. I–IV—copepodites I–IV; V–VI—copepodites V and adults. Trophic status. He—herbivorous; Om—omnivorous; Cr—carnivorous. Note that some taxa (e.g., Calanus spp. and Thyssanoessa spp.) may change their food preference in relation to environmental conditions. We indicate main trophic strategy for each mesozooplankton group. Biogeography: Bor—boreal; Ar—Arctic; Bor-Ar—Boreal-Arctic; Cs—cosmopolitan; Mx- mixed group.