The biology of a population of spined loach,Cobitis taeniaL.
作者:
Andrea Marconato,
MariaBerica Rasotto,
期刊:
Bolletino di zoologia
(Taylor Available online 1989)
卷期:
Volume 56,
issue 1
页码: 73-80
ISSN:0373-4137
年代: 1989
DOI:10.1080/11250008909355624
出版商: Taylor & Francis Group
关键词: Cobitis taenia;Growth;Production;Reproduction
数据来源: Taylor
摘要:
A spined loach (Cobitis taeniaL.) population inhabiting a small river in northern Italy was studied. At each age, females were larger than males and both sexes showed a marked seasonal pattern of growth with a high rate from May through November. Total population density averaged 2.38 ± 1.6 ind/m2and the annual production in the study area was 3.3 g/m2. The first year class during the summer accounts for more than half the production. The sex‐ratio did not significantly depart from unity. Most individuals achieved sexual maturity in their second spring after hatching and spawning occurred in late May and June. The relationship between female total length and fecundity was lnF=l.07+0.065L. Males showing three different liveries were found throughout the year; the seasonal variation in their frequency suggested that males change livery in relation to their reproductive conditions.
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