Age and stock structure of gemfish (Rexea solandri) in New Zealand waters
| Autor: | R. J. Hurst, P. L. Horn |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Gempylidae
geography geography.geographical_feature_category Ecology biology Fishing Estuary Aquatic Science Seasonality Oceanography biology.organism_classification medicine.disease Phylogeography medicine.anatomical_structure medicine Rexea solandri Bay Ecology Evolution Behavior and Systematics Otolith |
| Zdroj: | Marine and Freshwater Research. 50:103 |
| ISSN: | 1323-1650 |
| DOI: | 10.1071/mf98084 |
| Popis: | Age determination of gemfish by counting hyaline zones in otoliths was validated by following the progression of modes in length–frequency distributions and the progression of strong and weak year classes in age–frequency distributions. Length–frequency and otolith samples were examined from four areas (west Northland, east Northland and Bay of Plenty, Wairarapa coast, and the Stewart- Snares shelf). Age–frequency distributions and von Bertalanffy growth parameters were calculated and compared between areas. Two gemfish stocks are indicated on the basis of patterns of year class strengths, trends in commercial landings and likely spawning areas; one off the east and north of the North Island, and another off the west and south of the South Island. Estimates of natural mortality are presented for the two stocks. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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