Zivju kāpuru barošanās ekoloģija Rāznas ezerā
Date
2017
Authors
Buholce, Linda
Journal Title
Journal ISSN
Volume Title
Publisher
Latvijas Universitāte
Abstract
Zivju attīstības sākumā, kāpuriem pārslēdzoties no endogēnās uz eksogēno barošanos, vērojama visaugstākā organismu mirstība. Ņemot vērā to, ka informācija par zivju kāpuru barošanos saldūdeņos ir limitēta, tika veikts pētījums ar mērķi analizēt zivju kāpuru barošanās ekoloģiju Rāznas ezerā. Līdz ar to 2016. gada vasarā tika ievākti zivju kāpuri un to potenciālie barības objekti. Lielākoties Rāznas ezerā zivju kāpuri barojas ar Ceriodaphnia sp. īpatņiem. Organismam pieaugot, Ceriodaphnia sp. īpatņu loma zivju kāpuru kuņģos būtiski samazinās, savukārt Chironomidae īpatņu nozīme palielinās. Minams, ka visas zivju kāpuru garumu grupas izvairījušās baroties ar Cyclops spp. un Rotatoria indivīdiem. Kopumā secināms, ka zivju kāpuru barošanās ekoloģiju būtiski ietekmē barības objektu pieejamība vidē un zivs ķermeņa garums.
Highest mortality rate of fish larvea occures during early ontogeny when larvea switches from endogenous to exogenous feeding. It is important to note that limited number of studies could be found about larval fish feeding ecology in freshwater ecosystems. In order to fill the knowledge gap, a research took place regarding larval fish feeding in Lake Rāzna, Latvia. The samples of fish larvae and potential food sources in Lake Rāzna was collected during summer months, 2016. According to the study results, fish larvae mostly fed with Ceriodaphnia sp. Nevertheless, when reaching certain body size fish larvae becomes selective and starts to prefer Chironomidae in its feeding diet rather than Ceriodaphnia sp. Notably that all sampled fish larvae avoided to feed with Cyclops spp. and Rotatoria. To conclude, feeding ecology of fish larvae in Lake Rāzna is significantly incluenced by food availability and fish size.
Highest mortality rate of fish larvea occures during early ontogeny when larvea switches from endogenous to exogenous feeding. It is important to note that limited number of studies could be found about larval fish feeding ecology in freshwater ecosystems. In order to fill the knowledge gap, a research took place regarding larval fish feeding in Lake Rāzna, Latvia. The samples of fish larvae and potential food sources in Lake Rāzna was collected during summer months, 2016. According to the study results, fish larvae mostly fed with Ceriodaphnia sp. Nevertheless, when reaching certain body size fish larvae becomes selective and starts to prefer Chironomidae in its feeding diet rather than Ceriodaphnia sp. Notably that all sampled fish larvae avoided to feed with Cyclops spp. and Rotatoria. To conclude, feeding ecology of fish larvae in Lake Rāzna is significantly incluenced by food availability and fish size.
Description
Keywords
Bioloģija , zivju kāpuri , barošanās ekoloģija , Ceriodaphnia sp , .