Comparison of gut-evacuation rates of feeding and non-feeding Calanus marshallae |
| |
Authors: | S G Ellis L F Small |
| |
Institution: | (1) College of Oceanography, Oregon State University, 97331 Corvallis, Oregon, USA |
| |
Abstract: | Gut-evacuation rates were compared for feeding and non-feeding Calanus marshallae collected near Yaquina Bay, Oregon (44°37N; 124°04W) from June 1986 through May 1987. Evacuation rates were measured at four concentrations of Thalassiosira weissflogii from the decline of gut-pigment fluorescence following transfer of copepods to filtered seawater and from the loss of cells labelled with 68-germanium, a radioactive analog of silicon. There was no significant difference between gut-evacuation rates of feeding and non-feeding copepods over both short-term (20 min) and long-term (90 min) evacuation times. Furthermore there was no difference between rates obtained using either pigment or 68Ge as tracers of gut food-passage. These results are discussed in the light of possible dilution of tracer in the guts of feeding copepods due to mixing with unlabelled food. Gut-evacuation rates measured at food concentrations ranging from 500 to 4000 cells ml-1 were not significantly different, regardless of the technique employed. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|