The influence of structural complexity on fish-zooplankton interactions: A study using artificial submerged macrophytes

Authored by T Asaeda, T Priyadarshana, J Manatunge

Date Published: 2000

DOI: 10.1023/a:1007691425268

Sponsors: Japanese Ministries

Platforms: No platforms listed

Model Documentation: Other Narrative Mathematical description

Model Code URLs: Model code not found

Abstract

Aquatic macrophytes produce considerable structural variation within the littoral zone and as a result the vegetation provides refuge to prey communities by hindering predator foraging activities. The behavior of planktivorous fish Pseudorasbora parva (Cyprinidae) and their zooplankton prey Daphnia pulex were quantified in a series of laboratory experiments with artificial vegetation at densities of 0, 350, 700, 1400, 2100 and 2800 stems m(-2). Swimming speeds and foraging rates of the fish were recorded at different prey densities for all stem densities. The foraging efficiency of P. parva decreased significantly with increasing habitat complexity. This decline in feeding efficiency was related to two factors: submerged vegetation impeded swimming behavior and obstructed sight while foraging. This study separated the effects of swimming speed variation and of visual impairment, both due to stems, that led to reduced prey-predator encounters and examined how the reduction of the visual field volume may be predicted using a random encounter model.

Tags

Individual-based model Habitat use Predation risk Prey Vegetation Planktivorous fish Largemouth bass Shallow eutrophic lake Plant-density Bluegills