摘要:

Genetic differentiation in the New Zealand sea urchinEvechinus chloroticus(Valenciennes) was studied by examining individuals collected from six widely separated (250–2200 km apart) sites from around New Zealand for genetic variation at five polymorphic enzyme loci. Despite the large geographic separations, values of Nei's unbiased genetic distance,D(0–0.019) and standardised genetic variation among populations,FST(0.01–0.02) were small. This indicates high levels of gene flow among populations. However, one population sampled in a fiord in south‐western New Zealand was genetically differentiated from the others, although the scale of differentiation was not large (D =0.011–0.019). These findings indicate: (1) that the long‐lived planktotrophic larva ofE. chloroticusprovides this species with considerable dispersal ability throughout its range; and (2) that this is little affected by oceanographic features peculiar to its range, such as the Subtropical Convergence or the southward flowing East Cape Current. The slight differentiation of the fiord population probably results from restricted larval dispersal into and out of the fiord. In terms of management of theE. chloroticusfishery, the results provide no evidence for discrete stocks, with the possible exception of Fiordland. It is prudent to manage the fiord populations conservatively until they are better studied.

ISSN:0028-8330    

DOI:10.1080/00288330.1997.9516763

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Hydrographic and current meter measurements were performed to determine the important physical processes in Beatrix Bay, an enclosed bay in Pelorus Sound, South Island, New Zealand over a 9‐month period. The water within the bay was highly variable in temperature, salinity, and density, but strongly stratified on all occasions, with the stratification approximating a two‐layer system. The stratification was usually dominated by salinity, but on one occasion, following a period of low rainfall, the stratification was dominated by temperature. A crude estimate of the residence time for the water in Pelorus Sound is calculated from the relaxation towards oceanic salinities during the dry period. The currents measured were largely tidal, and showed evidence of a strong internal tide as a result of the quasi‐two‐layer stratification. The tidal flows were larger than those predicted by a simple model.

ISSN:0028-8330    

DOI:10.1080/00288330.1997.9516764

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

ISSN:0028-8330    

DOI:10.1080/00288330.1997.9516765

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

ISSN:0028-8330    

DOI:10.1080/00288330.1997.9516766

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor