Effects of flow regulation in the life-cycles of a Mediterranean cyprinid species, the Iberian chub (Squalius carolitertii Doadrio, 1988)

Frontiers in Marine Science

Teresa Ferreira¹  Carlos Manuel Alexandre²  Pedro Raposo de Almeida³ 

[1] CEF - Forestry Research Center;Escola de Ciências e Tecnologia, Universidade de Évora;Universidade de Évora;

关键词: flow regulation;    Streamflow;    Mediterranean rivers;    Iberian chub;    Fish life-cycles;   

DOI  :  10.3389/conf.fmars.2015.03.00002

来源: DOAJ

【 摘 要 】

River regulation tends to modify flow patterns, causing a reduction of discharge variability and disturbing environmentally cued life cycles of fishes. The objective of this study was to assess the changes in some of the most important life-cycle patterns of a resident freshwater fish species, the Iberian chub (Squalius carolitertii Doadrio 1988), caused by the hydrological alteration promoted by Vilarinho das Furnas Dam on River Homem. From May 2010 to June 2011, three sites were sampled in River Homem and three in River Vez, a nearby non-regulated river, selected as reference. Bi-monthly and fortnightly fish samples from the Iberian chub populations inhabiting the two selected rivers were collected and analyzed for fish age, growth and reproduction. River regulation operating in River Homem, for water derivation purposes, homogenized the flow pattern of the studied watercourse, causing a reduction in the magnitude and variability of monthly flow volumes that resulted in a set of bio-ecological deviations observed for the studied species. Shortly, seasonal pattern of gonad development was similar for male chubs from both rivers but distinct for females, particularly during the reproductive season. Moreover, female chubs inhabiting the non-regulated river presented higher fecundity but smaller oocytes than regulated river females. Seasonal pattern of fish condition was similar between the two rivers but chubs from the regulated river presented, globally, smaller values than the non-regulated river population. Findings from this study are important to understand the derivation in biological patterns imposed by regulated rivers on freshwater fish species and to be used as guiding elements for flow requirements implementations.

【 授权许可】

Unknown