Bathyal and abyssal polychaetes (annelids) from the central coast of Oregon

Graduation date: 1969Polychaete annelids from 48 benthic samples containing over\ud 2000 specimens were identified. Samples were taken with either an\ud anchor dredge or an anchor-box dredge from a 15 station transect\ud (44° 39. 1'N) that ranges from 800 to 2900 meters in depth. Sediment\ud subsamples were collected and analyzed for organic carbon and sediment\ud particle size using standard techniques. Temperature and\ud oxygen of the water near the bottom were taken with a modified Smith-\ud McIntyre grab; however, these measurements were not taken\ud simultaneously with the dredged biological samples.\ud The results indicated that at least 115 species in 53 families of\ud the class Polychaeta were represented in this transect line. This\ud study found an absence of the families Serpulidae and Syllidae and a\ud reduction of the number of speciesin the families Nereidae,\ud Cirratulidae and Capitellidae. Only five genera had not previously\ud been reported from the deep sea. The depth distribution of the\ud polychaetous annelids recovered in this study, coupled with limited\ud physical data, suggest that five faunal regions can be distinguished.\ud Nine new forms of polychaeteous annelids are tentatively described,\ud and others are anticipated in future collections. Suggestions for\ud future studies are also indicated