Trophic ecology and reproductive aspects of Trichomycterus areolatus (Pisces, Trichomycteridae) in irrigation canal environments.
Salvato in:
| Autori: | , , |
|---|---|
| Natura: | artículo original |
| Status: | Versión publicada |
| Data di pubblicazione: | 2005 |
| Descrizione: | Twelve of the sixteen species of fishes present in the Itata river basin enter the irrigation canals at least once a year, constituting a habitat that is frequently utilized by the native fish assemblages. However, only Trichomycterus areolatus, a native siluriform, is found in great number throughout the entire year, being the dominant species of such artificial environments. Among the factors that could explain the relative success of T. areolatus are its benthonic habits, adaptation to rithral habitat, an offer of trophic resources that is in line with its feeding habits, and a lower abundance of predators in the canals. In this study, the trophic ecology of this species in 174 individuals inhabiting the Itata river (Octava Región, Chile) and 231 from irrigation canals that arise from this river are analyzed and compared. In addition, the length-weight relationship and seasonal frequencies of reproductive status are analyzed, with the purpose of inferring on the status of these populations and their possible condition of resident in these canals. In canals, its diet includes a greater number of different taxa as well as total number of preys consumed in comparison with the river populations, including items of greater biomass, such as lumbriculides. The selectivity analysis showed that T. areolatus prefer prey items like Chironomidae, Baetidae, Elmidae, Plecoptera and Hyallela. Although both the river as well as canal populations show an isometric type growth, they reach greater body lengths and weights in the latter. According to the reproductive states analysis in different periods of the year, populations inhabiting canal environments reproduce synchronically with those of the river, although these latter tend to show a slight delay in the reproductive activity. |
| Stato: | Portal de Revistas UCR |
| Istituzione: | Universidad de Costa Rica |
| Repositorio: | Portal de Revistas UCR |
| Lingua: | Español |
| OAI Identifier: | oai:portal.ucr.ac.cr:article/14416 |
| Accesso online: | https://revistas.ucr.ac.cr/index.php/rbt/article/view/14416 |
| Access Level: | acceso abierto |
| Keyword: | trichomycterus feeding ecology reproduction irrigation canals Chile ecología de alimentación reproducción itata river canales de irrigación |