TY - JOUR
T1 - Precision of ingestion time and evacuation predictors for individual prey in stomachs of predatory fishes
AU - Andersen, Niels Gerner
AU - Beyer, Jan
PY - 2008
Y1 - 2008
N2 - Without evaluating precision, gastric evacuation models in combination with stomach data are widely used to investigate the feeding biology of wild predatory fishes. Assuming each predator individual to operate with its own evacuation rate parameter, the precision of estimated ingestion times for individual prey in the stomachs of predatory fishes was derived in this study. This way, the variability of gastric evacuation not accounted for by a deterministic model of gastric evacuation was described. The variability of initial body mass of ingested prey was included as well. General values 0.03 and 0.10 of the coefficients of variation sigma(m) and sigma(e) were obtained for the square root of initial prey mass and the evacuation rate parameter, respectively. They were estimated from length-mass data on a variety of fresh prey fishes and from data on gastric evacuation in the predatory gadoids whiting (Merlangius merlangus), Atlantic cod (Gadus morhua), and saithe (pollock) (Pollachius virens). Deriving the variance of gastric evacuation rate, evacuation time, and remaining prey mass, the study also established a basis for statistical analyses of the results obtained from laboratory experiments on gastric evacuation. (C) 2007 Elsevier B.V. All rights reserved.
AB - Without evaluating precision, gastric evacuation models in combination with stomach data are widely used to investigate the feeding biology of wild predatory fishes. Assuming each predator individual to operate with its own evacuation rate parameter, the precision of estimated ingestion times for individual prey in the stomachs of predatory fishes was derived in this study. This way, the variability of gastric evacuation not accounted for by a deterministic model of gastric evacuation was described. The variability of initial body mass of ingested prey was included as well. General values 0.03 and 0.10 of the coefficients of variation sigma(m) and sigma(e) were obtained for the square root of initial prey mass and the evacuation rate parameter, respectively. They were estimated from length-mass data on a variety of fresh prey fishes and from data on gastric evacuation in the predatory gadoids whiting (Merlangius merlangus), Atlantic cod (Gadus morhua), and saithe (pollock) (Pollachius virens). Deriving the variance of gastric evacuation rate, evacuation time, and remaining prey mass, the study also established a basis for statistical analyses of the results obtained from laboratory experiments on gastric evacuation. (C) 2007 Elsevier B.V. All rights reserved.
KW - Erhvervsfiskeri
U2 - 10.1016/j.fishres.2007.12.007
DO - 10.1016/j.fishres.2007.12.007
M3 - Journal article
SN - 0165-7836
VL - 92
SP - 11
EP - 22
JO - Fisheries Research
JF - Fisheries Research
IS - 1
ER -