ISSN:
1573-5133
Keywords:
Lepomis gibbosus
;
predation
;
searching volume
;
prey availability
;
clearance rate
;
feeding rate
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The effects of thermal stratification and light gradients on the feeding behavior of pumpkinseeds, Lepomis gibbosus, were tested in vertical aquarium columns. Successful captures, unsuccessful captures and unsuccessful searches by foraging sunfish on Daphnia pulex were recorded. Clearance and feeding rates of the sunfish were lowest when prey densities remained high, indicating that the Daphnia were occupying an area that could not be searched by the sunfish. Thermal stratification limited the searching volume and prey availability of the sunfish, while creating a refuge for the Daphnia. Light intensities ≤ 4.2 × 10-3 W m-2 decreased the searching and capture abilities of the sunfish under isothermal conditions. Thermal stratification had more of an effect than the light gradients, creating a refuge for the Daphnia causing them to be unavailable and less vulnerable to predation by the sunfish.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007432005348
Permalink