Record Details
Long-term variation in growth of Dover sole (Microstomous pacificus) and English sole (Parophrys vetulus), and its possible relationship with upwelling
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Long-term variation in growth of Dover sole (Microstomous pacificus) and English sole (Parophrys vetulus), and its possible relationship with upwelling |
| Names |
Kreuz, Keith Francis
(creator) Tyler, Albert V. (advisor) |
| Date Issued | 1978-09-15 (iso8601) |
| Note | Graduation date: 1979 |
| Abstract | Variation in growth rate of Dover sole (Microstomous pacificus) off Astoria and Brookings, and English sole (Parophrys vetulus) growth off Astoria and Coos Bay, Oregon was studied using the distance between annuli on scales and interoperculum bones indicating growth rate for Dover sole and English sole respectively. The age at which all individuals of a given year class are recruited to the trawl fishery is nine years for Dover sole and five years for English sole. Age-specific growth rate of Dover and English sole varies significantly between years. The maximum variation for Dover sole was 19% for the period from 1958 to 1975. English sole growth varied as much as 17% from the mean growth between 1961 and 1974. Dover and English sole captured off Astoria experienced good and poor growth during the same years as did Dover sole captured off Brookings located 460 km south of Astoria, and English sole captured 300 km south of Astoria off Coos Bay. The growth rate was slightly greater for Dover sole captured off Astoria than it was for Dover sole captured off Brookings. There was no significant difference in the growth rate for English sole captured off Astoria and off Coos Bay. Dover sole off Astoria experienced a general long-term increase in growth rate between 1958 and 1966 followed by a gradual decrease through 1969. A similar long-term trend occurred for English sole but was less apparent due to the shorter time series. The growing season for English sole begins in March and probably extends through September. The coldest temperatures at 50 in depth also occur during this period due to summer upwelling. The most rapid growth occurs during May and June. There is no evidence that the annual fluctuations in growth experienced by Dover and English sole are affected by temperature, upwelling or stock density. This study does suggest, however, that the long-term trends in growth are associated with similar long-term trends in upwelling. |
| Genre | Thesis/Dissertation |
| Topic | Flatfishes -- Growth |
| Identifier | http://hdl.handle.net/1957/22403 |
