Use of phytoplankton pigments in estimating food selection of three marine copepods

TY - JOUR

T1 - Use of phytoplankton pigments in estimating food selection of three marine copepods

AU - Christensen, Brian

AU - Jonasdottir, Sigrun

AU - Henriksen, Peter

AU - Hansen, Per Juel

PY - 2012/2

Y1 - 2012/2

N2 - Experiments were carried out to test the use of algal pigments in zooplankton grazing studies with a special emphasis on estimation of food selection. The results demonstrated that pigment composition of the phytoplankton food was reflected closely in the three copepod species Centropages typicus, Temora longicornis and Acartia tonsa, as well as in their faecal pellets. The fate of the phytoplankton pigments was studied in A. tonsa fed a diatom and a cryptophyte at a low and a high prey concentration. The concentration of gut pigments generally declined rapidly within the first 510 min after feeding terminated. The decline in pigment concentration was faster in copepods fed high concentrations of phytoplankton and specially when fed the diatom. However, after 3h of no feeding only minor changes in gut pigment composition were found mainly in alloxanthin, chlorophyll a and diadinoxanthin. Traditional grazing experiments were carried out in parallel with pigment analysis in experiments where the copepod A. tonsa was exposed to a mixture of food organisms. The results demonstrated that the two methods gave similar results with regard to food selection and that with certain precautions, pigment analysis can be successfully used in food selection studies.

AB - Experiments were carried out to test the use of algal pigments in zooplankton grazing studies with a special emphasis on estimation of food selection. The results demonstrated that pigment composition of the phytoplankton food was reflected closely in the three copepod species Centropages typicus, Temora longicornis and Acartia tonsa, as well as in their faecal pellets. The fate of the phytoplankton pigments was studied in A. tonsa fed a diatom and a cryptophyte at a low and a high prey concentration. The concentration of gut pigments generally declined rapidly within the first 510 min after feeding terminated. The decline in pigment concentration was faster in copepods fed high concentrations of phytoplankton and specially when fed the diatom. However, after 3h of no feeding only minor changes in gut pigment composition were found mainly in alloxanthin, chlorophyll a and diadinoxanthin. Traditional grazing experiments were carried out in parallel with pigment analysis in experiments where the copepod A. tonsa was exposed to a mixture of food organisms. The results demonstrated that the two methods gave similar results with regard to food selection and that with certain precautions, pigment analysis can be successfully used in food selection studies.

U2 - 10.1093/plankt/fbr090

DO - 10.1093/plankt/fbr090

M3 - Journal article

SN - 0142-7873

VL - 34

SP - 161

EP - 172

JO - Journal of Plankton Research

JF - Journal of Plankton Research

IS - 2

ER -