Graduation date: 1980

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

A study was undertaken in Yaquina Bay, Oregon during the summer of 1964 to determine the distribution and the factors affecting the distribution of the polychaete worm, Nephtys caecoides, Hartman, 1938, in the estuary. This organism has a continuous distribution from offshore to a point approximately eight kilometers into the bay. Environmental factors considered were salinity, temperature, and sediment composition. The results of this study do not single out a factor as the one limiting the distribution of N. caecoides in Yaquina Bay. During summer months, it is possible that sediment porosity, organic content and temperature operate together to form an unfavorable environment. / Graduation date: 1966

v, 51 leaves : ill. ; 29 cm Notes Typescript. (Another copy on microfilm is located in Archives) Thesis (M.S.)--University of Oregon Includes vita Bibliography: leaves 46-51

Note:

Thesis (M.S.) in Marine Biology--University of Maine, 2001. / Includes vita. Includes bibliographical references (leaves 82-92).

Thesis (Ph. D.)--University of Hong Kong, 2008. / Includes bibliographical references (leaf 211-245) Also available in print.

Typescript. Includes vita and abstract. Includes bibliographical references (leaves 134-154). Also available online in Scholars' Bank; and in ProQuest, free to University of Oregon users.

Taxonomic works relating to polychaetes from the Falkland Islands are few and little has been published specifically on them since the early to mid twentieth century. Unusually, the intertidal region has received less attention than subtidal sites with most information coming from Antarctic expeditions that used the Islands as a staging post on their journeys south. Works relating to the wider Magellan region, as well as the Antarctic, are far more numerous. The project detailed by this thesis was conceived to address this dearth of knowledge, put the information gleaned into context with the biogeographical region within which the Falkland Islands sit and to determine whether species distribution around the Islands is affected by the differing current regimes that influence the surrounding waters. In total, 218 taxa are reported, 52 of which have been named so far, including four new species whose published descriptions form part of this document. Over 85% of the named species are already known from the wider Magellan region and significant overlap with South Georgian and Antarctic faunas is also apparent. Cluster analyses and multi-dimensional scaling plots show depth (intertidal versus subtidal) to be the strongest influence on species composition with shore height and sediment type having limited effect and geographic location none. Taxonomic distinctness indices are used to assess the species lists and compare sample sites. Much of the diversity appears to centre on microhabitats such as epifaunal and algal turfs and biogenic encrustations. Syllidae are the most diverse family and dominate some samples, particularly those from epifaunal turf and sieved sediments. Other families appear to use microhabitats, such as epifaunal turf and biogenic encrustations, as nursery areas, with large numbers of juveniles in some samples. Comparisons are made with other intertidal diversity studies from the Scotia Arc and Antarctic.

No description available.