An experimental test of how parasites of predators can influence trophic cascades and ecosystem functioning

Anaya-Rojas, Jaime M.; Best, Rebecca J.; Brunner, Franziska S.; Eizaguirre, Christophe; Leal, Miguel Costa; Mélian, Carlos J.; Seehausen, Ole; Matthews, Blake (2019). An experimental test of how parasites of predators can influence trophic cascades and ecosystem functioning. Ecology, 100(8) Ecological Society of America 10.1002/ecy.2744

[img]
Preview
Text
Anaya-Rojas_et_al-2019-Ecology.pdf - Published Version
Available under License Publisher holds Copyright.

Download (707kB) | Preview

Parasites can shape the structure and function of ecosystems by influencing both the density and traits of their hosts. Such changes in ecosystems are particularly likely when the host is a predator that mediates the dynamics of trophic cascades. Here, we experimentally tested how parasite load of a small predatory fish, the threespine stickleback, can affect the occurrence and strength of trophic cascades and ecosystem functioning. In a factorial mesocosm experiment, we manipulated the density of stickleback (low vs. high), and the level of parasite load (natural vs. reduced). In addition, we used two stickleback populations from different lineages: an eastern European lineage with a more pelagic phenotype (Lake Constance) and a western European lineage with a more benthic phenotype (Lake Geneva). We found that stickleback caused trophic cascades in the pelagic but not the benthic food chain. Evidence for pelagic trophic cascades was stronger in treatments where parasite load of stickleback was reduced with an antihelmintic medication, and where fish originated from Lake Constance (i.e., the more pelagic lineage). A structural equation model revealed that differences in stickleback lineage and parasite load were most likely to impact trophic cascades via changes in the composition, rather than overall biomass, of zooplankton communities. Overall, our results provide experimental evidence that parasites of predators can influence the cascading effects of fish on lower trophic levels with consequences on ecosystem functioning.

Item Type:

Journal Article (Original Article)

Division/Institute:

08 Faculty of Science > Department of Biology > Institute of Ecology and Evolution (IEE) > Aquatic Ecology
08 Faculty of Science > Department of Biology > Institute of Ecology and Evolution (IEE)

UniBE Contributor:

Anaya-Rojas, Jaime Mauricio; Melian Penate, Carlos Javier and Seehausen, Ole

Subjects:

500 Science > 570 Life sciences; biology

ISSN:

0012-9658

Publisher:

Ecological Society of America

Language:

English

Submitter:

Marcel Häsler

Date Deposited:

20 Jan 2020 09:36

Last Modified:

20 Jan 2020 09:36

Publisher DOI:

10.1002/ecy.2744

BORIS DOI:

10.7892/boris.138367

URI:

https://boris.unibe.ch/id/eprint/138367

Actions (login required)

Edit item Edit item
Provide Feedback