| Autor: |
B E A, Rochowski, T I, Walker, R W, Day |
| Rok vydání: |
2015 |
| Předmět: |
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| Zdroj: |
Journal of fish biology. 87(3) |
| ISSN: |
1095-8649 |
| Popis: |
Deania calcea (n = 420) were collected from the catch of deep-water trawlers in the southern and eastern scalefish and shark fishery in southern Australia during the years 2008-2011. The total length (LT ) range varied between sexes, females being larger (n = 264; 280-1530 mm) than males (n = 156; 310-921 mm). The reproductive cycle in this population is non-continuous and asynchronous. The estimated LT at which 50% of males are mature is 807 mm and is 914 mm for females. Populations of D. calcea in higher latitudes appear to mature at a larger size than conspecifics in lower latitudes, in both the northern and southern hemispheres. Litters ranged from three to 10 embryos with a 1:1 sex ratio, but litter size does not increase with maternal LT . Deania calcea shows geographical variability in its biological parameters and gathering information on life-history traits of populations is vital to understand the trade-offs made by this species in response to environmental conditions and to predict intraspecific spatial differences. Such information is a basis for specific spatial management to protect populations from excessive fishing. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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