English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Laboratory experiments on the gastric evacuation of juvenile herring (Clupea harengus L.)

MPS-Authors
There are no MPG-Authors available
Locator
There are no locators available
Fulltext (public)
There are no public fulltexts available
Supplementary Material (public)
There is no public supplementary material available
Citation

Bernreuther, M., Herrmann, J.-.-P., & Temming, A. (2008). Laboratory experiments on the gastric evacuation of juvenile herring (Clupea harengus L.). JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY, 363(1-2), 1-11. doi:10.1016/j.jembe.2008.05.012.


Cite as: http://hdl.handle.net/11858/00-001M-0000-0018-2506-E
Abstract
Laboratory experiments were conducted on groups of 9.9 to 13 cm (mean) total length (LT) juvenile herring (Clupea harengus L.) to describe the temperature dependency of the gastric evacuation. Experiments were conducted at 13 and 16 degrees C. The parameters of the general gastric evacuation model were B=0.953 and R=0.082 at 13 degrees C and B=1.323 and R=0.843 at 16 degrees C indicating an exponential evacuation. The evacuation constants of the exponential gastric evacuation model were R=0.098 at 13 and R=0.202 at 16 degrees C resulting in a temperature dependency parameter (A) of 0.241. The internal dynamics of the stomach and its storage capacity were studied by the use of stained copepods. Investigations on the functional response of herring to different food densities were described by the Michaelis-Menten equation. Our experimental design allowed us to test the hypothesis of Richter et al. [Richter, H., Luckstadt, C., Schlechtriem, C., Focken, U., Becker, K., 2002. Do the fish stomach content models currently used for daily ration estimation really work? Evidence of violation of a basic assumption concerning stomach evacuation rates. Arch. Fish. Mar. Res. 49 (3), 171-188] that fish have two evacuation modes, one evacuation constant while only evacuating food and a significant higher constant while feeding, which would question the basic assumption of most consumption models, that only use one evacuation constant for consumption estimates. The experiments of Richter et al. [Richter, H., Luckstadt, C., Schlechtriem, C., Focken, U., Becker, K., 2002. Do the fish stomach content models currently used for daily ration estimation really work? Evidence of violation of a basic assumption concerning stomach evacuation Fates. Arch. Fish. Mar. Res. 49 (3), 171-188] suggested that a doubled constant would give the best match of observed feeding and estimates of consumption models. Through the results of simulations of two experiments in which we combined observed snatching rates, estimated evacuation constants and particle weights of consumed copepods, we cannot support this hypothesis. A doubled evacuation constant did not improve our simulations, on the contrary the simulations with a doubled constant gave a worse fit with our observed values. Knowledge on the gastric evacuation is a prerequisite for the evaluation of a potential top-down impact of this zooplanktivorous species on the plankton community. (C) 2008 Elsevier B.V. All Fights reserved.