| Table 5. Characteristics of the three faunal groups and their habitats recognized by Reid et al. (1979) via cluster analysis of 1972 samples. Shown are the mean densities per m2 and coeffiecient of variation (in parentheses) of dominant infaunal species in 1972 and 1973 (based on data presented in Tables 4,5 and 6 in Reid et al. 1979) and for the muddy, deepwater group for 1975-1978 based on data presented in Table 3 in Reid (1979). Means are based on all samples in each group; means for total numbers of individuals and species are based on all species found at each station. See Figure 10 for the spatial distributions of each group. | ||||||
| Muddy, Deep-Water Group | ||||||
| Group and Habitat Characteristics | ||||||
| # Stations | 43 | |||||
| Level of Similarity: | >50% | |||||
| % Silt - Clay: | >69% | |||||
| Depth: | >15 m | |||||
| Dominant Infaunal Species | ||||||
| POLYCHAETES | 1972 | 1973 | 1975 | 1976 | 1977 | 1978 |
| Nephtys incisa | 60 (68) | 100 (92) | 71 (44) | 79 (82) | 147(65) | 181 (42) |
| Pherusa affinis | 50 (122) | 45 (290) | 13 (216) | 19 (209) | 22 (213) | 21 (180) |
| Polydora ligni | 157 (291) | 2 (211) | 0 | 1 (320) | 44 (216) | 22 (316) |
| Mediomastus ambiseta | 11 (529) | 288 (367) | 0 | 5 (254) | 48 (124) | 35 (174) |
| PELECYPODS | ||||||
| Nucula annulata | 483 (222) | 324(216) | 264 (166) | 791 (173) | 262 (119) | 444 (112) |
| Yoldia limatula | 191 (155) | 51 (267) | 34 (229) | 42 (147) | 106 (95) | 175 (109) |
| Pitar morrhuana | 357 (72) | 4 (143) | 60 (122) | 18 (131) | 25 (195) | 114 (103) |
| Mulinia lateralis | 8,217 (61) | 11 (276) | 144 (239) | 232 (279) | 673 (130) | 1,074 (106) |
| CRUSTACEANS | ||||||
| Amplesica abdita | 53 (132) | 26(275) | 0 | 1 (320) | 0 | 0 |
| Total Density | 10,400 (56) | 1,263 (136) | 861 (82) | 1,314 (125) | 1,457 (58) | 2,310 (73) |
| Total Species | 21.2 (31) | 10.1 (65) | 9.8 (53) | 8.9 (67) | 11.2 (19) | 14.2 (43) |
| Shallow Sandy Group | ||||||
| Group and Habitat Characteristics | ||||||
| # Stations: | 12 | |||||
| Level of Similarity: | >37% | |||||
| % Silt - Clay: | <3.7% | |||||
| Depth: | <15 m | |||||
| Dominant Infaunal Species | ||||||
| POLYCHAETES | 1972 | 1973 | ||||
| Nephtys picta | 75 (98) | 48 (92) | ||||
| Spiophanes bombyx | 25 (133) | 207 (113) | ||||
| Aricidea catherinae | 45 (194) | 6 (180) | ||||
| PELECYPODS | ||||||
| Tellina agilis | 445 (170) | 1,910 (206) | ||||
| Ensis directus | 122 (130) | 74 (155) | ||||
| Spisula solidissima | 795 (194) | 29 (162) | ||||
| CRUSTACEANS | ||||||
| Amplesica vadorum | 98 (188) | 49 (212) | ||||
| Paraphoxus epistonus | 52 (159) | 89 (172) | ||||
| Total Density | 6,938 (189) | 3,703 (135) | ||||
| Total Species | 23.1 (31) | 22.9 (65) | ||||
| Shallow Transitional Group | ||||||
| Group and Habitat Characteristics | ||||||
| # Stations: | 21 | |||||
| Level of Similarity: | >41% | |||||
| % Silt - Clay: | mixed | |||||
| Depth: | <20 m | |||||
| Dominant Infaunal Species | ||||||
| POLYCHAETES | 1972 | 1973 | ||||
| Mediomastus ambiseta | 175 (159) | 143 (257) | ||||
| Polydora ligni | 7,131 (187) | 1 (360) | ||||
| Streblospio benedicti | 1,549 (138) | 14 (160) | ||||
| Tharyx accutus | 533 (204) | 4 (169) | ||||
| Ampharete arctica | 415 (185) | 43 (178) | ||||
| PELECYPODS | ||||||
| Tellina agilis | 418 (170) | 222 (110) | ||||
| Ensis directus | 281 (130) | 104 (119) | ||||
| CRUSTACEANS | ||||||
| Amelisca abdita | 96 (194) | 44 (278) | ||||
| Amplesica vadorum | 81 (220) | 508 (260) | ||||
| Total Density | 14,037 (118) | 2,362 (62) | ||||
| Total Species | 34.3 (27) | 23.8 (52) | ||||