World Library  


Add to Book Shelf
Flag as Inappropriate
Email this Book

Plos One : Seasonal Trophic Niche Shift and Cascading Effect of a Generalist Predator Fish, Volume 7

By Krkosek, Martin

Click here to view

Book Id: WPLBN0003959681
Format Type: PDF eBook :
File Size:
Reproduction Date: 2015

Title: Plos One : Seasonal Trophic Niche Shift and Cascading Effect of a Generalist Predator Fish, Volume 7  
Author: Krkosek, Martin
Volume: Volume 7
Language: English
Subject: Journals, Science, Medical Science
Collections: Periodicals: Journal and Magazine Collection (Contemporary)
Historic
Publication Date:
Publisher: Plos

Citation

APA MLA Chicago

Krkosek, M. (n.d.). Plos One : Seasonal Trophic Niche Shift and Cascading Effect of a Generalist Predator Fish, Volume 7. Retrieved from http://read.schoollibrary.com/


Description
Description : Few studies have examined how foraging niche shift of a predator over time cascade down to local prey communities. Here we examine patterns of temporal foraging niche shifts of a generalist predator (yellow catfish, Pelteobagrus fulvidraco) and the abundance of prey communities in a subtropical lake. We predicted that the nature of these interactions would have implications for patterns in diet shifts and growth of the predator. Our results show significant decreases in planktivory and benthivory from late spring to summer and autumn, whereas piscivory increased significantly from mid-summer until late autumn and also increased steadily with predator body length. The temporal dynamics in predator/prey ratios indicate that the predation pressure on zooplankton and zoobenthos decreased when the predation pressure on the prey fish and shrimps was high. Yellow catfish adjusted their foraging strategies to temporal changes in food availability, which is in agreement with optimal foraging theory. Meanwhile the decrease in planktivory and benthivory of yellow catfish enabled primary consumers, such as zooplankton and benthic invertebrates, to develop under low grazing pressure via trophic cascading effects in the local food web. Thus, yellow catfish shifts its foraging niche to intermediate consumers in the food web to benefit the energetic demand on growth and reproduction during summer, which in turn indirectly facilitate the primary consumers. In complex food webs, trophic interactions are usually expected to reduce the strength and penetrance of trophic cascades. However, our study demonstrates strong associations between foraging niche of piscivorous fish and abundance of prey. This relationship appeared to be an important factor in producing top-down effects on both benthic and planktonic food webs.

 
 



Copyright © World Library Foundation. All rights reserved. eBooks from School eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.