Digital Archives Initiative
Memorial University - Electronic Theses and Dissertations 5
menu off  add document to favorites : add page to favorites : reference url back to results : previous : next
 Search this object:
 0 hit(s) :: previous hit : next hit
  previous page : next page
Document Description
TitleA study of northern Atlantic cod (Gadus morhua) of eastern Newfoundland and Labrador as a metapopulation
AuthorSmedbol, R. Kent, 1968-
DescriptionThesis (Ph.D.)--Memorial University of Newfoundland, 1999. Biology
Paginationxv, 130 leaves : ill., maps
SubjectAtlantic cod--Spawning--Newfoundland and Labrador; Atlantic cod--Newfoundland and Labrador--Geographical distribution; Fish populations--Newfoundland and Labrador--Measurement
Degree GrantorMemorial University of Newfoundland. Dept. of Biology
Spatial CoverageCanada--Newfoundland and Labrador
NotesBibliography: leaves 109-119.
AbstractI present a model of intrapopulation structure in northern Atlantic cod (Gadus morhua) inhabiting the coastal and continental shelf regions off northeast Newfoundland and Labrador based on metapopulation dynamics. I suggest that the metapopulation concept may best explain the historical patterns and present day observations of northern cod distribution. Evidence for subpopulation structure is assembled from new and published data sources, including studies of spawning time and location, migration behaviour, and genetic variation. A theoretical model of northern cod metapopulation dynamics is derived from the simple model of Levins (1970). I consider the various spawning components of northern cod historically centered on the offshore banks and in coastal bays as subpopulations of a northern cod metapopulation. I modify the Levins (1970) model by separating the probability of subpopulation extinction into two component probabilities representing: (1) natural processes and (2) the effects of fishing. Metapopulation theory predicts that fewer suitable areas (spawning grounds) will be occupied as population abundance declines. The corollary prediction is that as population abundance recovers, spawners will recolonize the currently unoccupied spawning areas. The agents of colonization may be migratory adult fish and straying larvae. The model supports the current view that overfishing may have played an important role in the extinction of northern subpopulations off Labrador.
Resource TypeElectronic thesis or dissertation
FormatImage/jpeg; Application/pdf
SourcePaper copy kept in the Centre for Newfoundland Studies, Memorial University Libraries
RightsThe author retains copyright ownership and moral rights in this thesis. Neither the thesis nor substantial extracts from it may be printed or otherwise reproduced without the author's permission.
CollectionElectronic Theses and Dissertations
Scanning StatusCompleted
PDF File(22.60 MB) --
CONTENTdm file name45914.cpd