Trends in wild adult steelhead (Oncorhynchus mykiss) abundance for coastal regions of British Columbia support the variable marine survival hypothesis

2000 ◽  
Vol 57 (2) ◽  
pp. 271-284 ◽  
Author(s):  
Barry D Smith ◽  
Bruce R Ward
Keyword(s):  
British Columbia ◽  
Oncorhynchus Mykiss ◽  
West Coast ◽  
Coastal Upwelling ◽  
Vancouver Island ◽  
Fiscal Year ◽  
Coastal Regions ◽  
Queen Charlotte Islands ◽  
Marine Survival

Wild adult steelhead (Oncorhynchus mykiss) abundance for rivers in British Columbia was indexed using catch-per-angler-day (CpAD) calculated from data obtained using an angler questionnaire. Mean annual CpAD for primarily winter-run steelhead in rivers of four rainfall-driven coastal regions of British Columbia showed similar trends from the fiscal year 1967-1968 to 1989-1990. After 1989-1990 the trends diverged. The generally remote rivers of the west coast of Vancouver Island and the Queen Charlotte Islands maintained a steady or increasing trend in CpAD after 1989-1990. The long-term trend for these two regions correlated well with a joint index of winter and summer upwelling for the Coastal Upwelling Domain for the years that steelhead are at sea and is consistent with studies that relate marine survival of salmon to oceanic-atmospheric climate. In contrast with west coast Vancouver Island and the Queen Charlotte Islands, most rivers of the east coast of Vancouver Island and the lower mainland near Vancouver revealed declining trends since 1989-1990. Most of these rivers drain into the Strait of Georgia. Reasons for the discrepancy among regions after about 1990 are discussed. They include high angling pressure related to hatchery supplementation, differences in riverine and marine conditions, and smolt migration distance.

scholarly journals Seasonal Variation of Temperature and Salinity of Surface Waters of the British Columbia Coast

1953 ◽  
Vol 10 (3) ◽  
pp. 125-145 ◽  
Author(s):  
G. L. Pickard ◽  
D. C. McLeod
Keyword(s):  
British Columbia ◽  
West Coast ◽  
Sea Water ◽  
Deep Ocean ◽  
Vancouver Island ◽  
Early Summer ◽  
The West ◽  
Queen Charlotte Islands ◽  
Land Drainage ◽  
Run Off

Grand monthly means of daily observations of surface sea-water temperature and salinity from twelve light stations along the British Columbia coast during the 13 years 1935 to 1948 have been analysed. In general the temperatures reach a minimum of 45°F. ± 1° (7.2 °C. ± 0.5°) in January and February. The maximum varies from 50° to 64°F. (10° to 18 °C.) in August. The warmest waters occur in bays protected from wind action, and the coldest waters occur in regions of turbulent mixing due to wind or strong currents. The salinity along the mainland coast is a minimum in early summer, associated with the maximum run-off from melting snow. Along the west coast of Vancouver Island the minimum occurs in mid-winter, associated with maximum precipitation which is not stored as snow in this region. At the southern and northern tip of the Queen Charlotte Islands there is little or no variation of salinity because there is no land drainage of consequence in the vicinity.In passes between Georgia Strait and the sea where the waters are mixed to homogeneity by strong tidal currents the annual variation of temperature and salinity is reduced, and in some cases entirely suppressed.On the west coast of Vancouver Island it is shown that the annual cycle is affected by the dominant winds and upwelling of deep ocean waters.

Holocene sea-level change on the central west coast of Vancouver Island, British Columbia

1993 ◽  
Vol 30 (4) ◽  
pp. 832-840 ◽  
Author(s):  
Pierre A. Friele ◽  
Ian Hutchinson
Keyword(s):  
British Columbia ◽  
Sea Level ◽  
West Coast ◽  
Late Holocene ◽  
Vancouver Island ◽  
Simple Simulation ◽  
Coastal Deposits ◽  
Study Sites ◽  
Topographic Surveys

A new Holocene relative-sea-level (RSL) curve is proposed for the central west coast of Vancouver Island based on topographic surveys of coastal landforms and the stratigraphy of coastal deposits. Six study sites are described on Vargas Island and Esowista and Ucluth peninsulas and 23 previously unpublished radiocarbon ages that constrain mean-sea-level (MSL) position are presented. A long-term rise in RSL from an early Holocene (> 7000 BP) lowstand below −3 m asl is documented from dates on tree stumps in the intertidal zone and salt-marsh peats and forest-floor deposits buried by marine sands and gravels. Submergence culminated in a stillstand from 6000 to 4800 BP, marked by the development of a strandline at 6 m asl (MSL ≈ 3.2 m asl). A fall in RSL is documented by a strandline at 4.0–4.5 m asl, which dates from 2700 to 2000 BP (MSL ≈ 2.0 m asl). Little is known of the dynamics of emergence between 4800 and 2700 BP or from 2000 BP to the present, although the absence of strandlines below 4 m asl suggests continuous emergence during the last two millenia. This submergence–emergence cycle is unique in southern British Columbia. A simple simulation model suggests that late Holocene emergence was induced by tectonic uplift of the edge of the America plate margin.

The Relation of Weather to Population Trends of the Black-headed Budworm Acleris variana (Fern.) (Lepidoptera: Tortricidae)

1960 ◽  
Vol 92 (6) ◽  
pp. 401-410 ◽  
Author(s):  
G. T. Silver
Keyword(s):  
British Columbia ◽  
West Coast ◽  
Vancouver Island ◽  
Tsuga Heterophylla ◽  
Population Trends ◽  
Western Hemlock ◽  
Canal Area ◽  
Queen Charlotte Islands ◽  
History Of ◽  
Coastal British Columbia

The history of the black-headed budworm, Acleris variana (Fern.), in the western hemlock (Tsuga heterophylla (Raf.) Sarg.) forests of coastal British Columbia is one of recurring cycles of outbreaks. The latest cycle occurred from 1952 to 1957 and was represented by three main outbreaks in the Portland Canal area from Prince Rupert to Stewart, the Queen Charlotte Islands, and on northern Vancouver Island. Previous to this, groups of West Coast outbreaks were recorded from 1940 to 1945, and from 1927 to 1931 (Prebble and Graham, 1945a).

Trends in wild adult steelhead (Oncorhynchus mykiss) abundance in British Columbia as indexed by angler success

2000 ◽  
Vol 57 (2) ◽  
pp. 225-270 ◽  
Author(s):  
Barry D Smith ◽  
Bruce R Ward ◽  
David W Welch
Keyword(s):  
British Columbia ◽  
Time Series ◽  
Oncorhynchus Mykiss ◽  
Coastal Upwelling ◽  
Fiscal Year ◽  
Climate Indices ◽  
Factors Affecting ◽  
Gradual Introduction ◽  
Trends Over Time ◽  
Over Time

Intraregional similarities and interregional differences in wild steelhead (Oncorhynchus mykiss) abundance trends over time throughout British Columbia were identified using catch-per-angler-day (CpAD) as an index of abundance. This index was calculated using sport angler catch and effort data obtained by an ongoing mail-out questionnaire begun in the fiscal year 1967-1968. Despite high interannual variability in CpAD for individual rivers, its validity as an index of trends over time in wild steelhead abundance for geographic regions or watersheds is reinforced by similar trends yielded by both fishery-dependent and fishery-independent data. Time series methods generally could not build statistical support for the hypotheses that sudden regulation changes, or the gradual introduction over time of a catch and release philosophy, are generally important factors affecting trends over time in CpAD. This bolsters our confidence that the general patterns in mean CpAD over time within regions and watersheds reasonably index actual wild adult in-river steelhead abundance. We propose that the trends that we observe in wild steelhead CpAD are primarily driven by environmental influences. Some candidate environmental time series currently being considered and investigated are coastal upwelling, various ocean and atmospheric climate indices, freshwater discharge histories, and ultraviolet radiation.

The nootka and sandwich vocabularies in the relación de la entrada de san lorenzo de nutka (1789)

2013 ◽  
Vol 66 (3) ◽  
Author(s):  
Rebeca Fernández Rodríguez
Keyword(s):  
British Columbia ◽  
West Coast ◽  
Vancouver Island ◽  
The West ◽  
San Lorenzo

AbstractNootka is an historical fur-trading centre in Yuquot, on the west coast of Vancouver Island, British Columbia, Canada. In 1788, the Spanish king Charles III sent an expedition to Nootka commanded by Ignacio Arteaga (1731-1783). A year later, Spain established a military post, San Lorenzo de Nutka, at Yuquot in 1789 which existed until 1795. The missionaries who arrived with the sailors were urged to learn the vernacular languages in order to evangelize. In chapter 5 of the

A Model of Seawater Structure Near the West Coast of Vancouver Island, British Columbia

1963 ◽  
Vol 20 (4) ◽  
pp. 939-967 ◽  
Author(s):  
Robert K. Lane
Keyword(s):  
British Columbia ◽  
West Coast ◽  
Large Scale ◽  
Coastal Region ◽  
Vancouver Island ◽  
Structural Elements ◽  
The West ◽  
Characteristic Structure ◽  
Oceanographic Data ◽  
Vertical Sections

Oceanographic data collected in a line of stations extending seaward of the west coast of Vancouver Island, British Columbia, were reviewed and analyzed. On the basis of these data and the large-scale meteorological processes of wind, insolation, and precipitation, the characteristic structure of temperature and salinity in the coastal region was denned in five temporal stages throughout the year. These stages are presented as vertical sections along the line with characteristic ranges of values to be found in each of the structural elements.

RECORDS OF SOME SPECIES OF POLYCHAETA NEW TO BRITISH COLUMBIA AND OF EXTENSIONS IN DISTRIBUTION OF SOME OTHERS

1966 ◽  
Vol 44 (5) ◽  
pp. 839-849 ◽  
Author(s):  
C. Berkeley
Keyword(s):  
British Columbia ◽  
North America ◽  
West Coast ◽  
Vancouver Island ◽  
The Other ◽  
The West ◽  
New Subspecies ◽  
Northeast Pacific ◽  
Considerable Depth ◽  
Geographical Locations

Twenty-five species of Polychaeta recently collected off the coast of British Columbia are discussed. Most were taken in waters of considerable depth off the west coast of Vancouver Island. Sixteen are new to British Columbia. Most of these are known from farther south on the west coast of North America, but some from much shallower depths than those from which they are now recorded; two of them are new to the northeast Pacific; one is a new subspecies. The other nine have been previously known from British Columbia, but they are now recorded from much greater depths than hitherto, or in new geographical locations.

Lampetra macrostoma, a New Species of Freshwater Parasitic Lamprey from the West Coast of Canada

1982 ◽  
Vol 39 (5) ◽  
pp. 736-747 ◽  
Author(s):  
Richard J. Beamish
Keyword(s):  
British Columbia ◽  
New Species ◽  
West Coast ◽  
Related Species ◽  
Salt Water ◽  
Vancouver Island ◽  
The West ◽  
Large Disc ◽  
Large Numbers ◽  
A New Species

Lampetra macrostoma n.sp., a freshwater parasitic lamprey, is distinguished from related species L. tridentata, L. lethophaga, L. folletti, L. minima, and L. similis by its parasitic habit and very large disc. Other characters distinguishing the species from L. tridentata are its longer prebranchial length, large eye, weakly pigmented velar tentacles, and its ability to remain in freshwater. The recently metamorphosed form readily survives in freshwater and probably is non-anadromous even though it can survive in salt water. The new species has been discovered in two lakes on Vancouver Island, British Columbia, Canada, where it attacks large numbers of resident salmonids. Because of its ability to survive and feed in freshwater, it poses a definite threat to freshwater fishes.Key words: lamprey, new species, non-anadromous lamprey, salmonid parasitism

Sign in / Sign up

Export Citation Format

Share Document