| Title: |
Latitude and protection affect decadal trends in reef trophic structure over a continental scale |
| Authors: |
Madin EMP; Madin JS; Harmer AMT; Barrett NS; Booth DJ; Caley MJ; Cheal AJ; Edgar GJ; Emslie MJ; Gaines SD; Sweatman HPA |
| Publisher Information: |
Wiley |
| Publication Year: |
2020 |
| Collection: |
University of Technology Sydney: OPUS - Open Publications of UTS Scholars |
| Subject Terms: |
0602 Ecology; 0603 Evolutionary Biology |
| Description: |
© 2020 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. The relative roles of top-down (consumer-driven) and bottom-up (resource-driven) forcing in exploited marine ecosystems have been much debated. Examples from a variety of marine systems of exploitation-induced, top-down trophic forcing have led to a general view that human-induced predator perturbations can disrupt entire marine food webs, yet other studies that have found no such evidence provide a counterpoint. Though evidence continues to emerge, an unresolved debate exists regarding both the relative roles of top-down versus bottom-up forcing and the capacity of human exploitation to instigate top-down, community-level effects. Using time-series data for 104 reef communities spanning tropical to temperate Australia from 1992 to 2013, we aimed to quantify relationships among long-term trophic group population density trends, latitude, and exploitation status over a continental-scale biogeographic range. Specifically, we amalgamated two long-term monitoring databases of marine community dynamics to test for significant positive or negative trends in density of each of three key trophic levels (predators, herbivores, and algae) across the entire time series at each of the 104 locations. We found that trophic control tended toward bottom-up driven in tropical systems and top-down driven in temperate systems. Further, alternating long-term population trends across multiple trophic levels (a method of identifying trophic cascades), presumably due to top-down trophic forcing, occurred in roughly fifteen percent of locations where the prerequisite significant predator trends occurred. Such alternating trophic trends were significantly more likely to occur at locations with increasing predator densities over time. Within these locations, we found a marked latitudinal gradient in the prevalence of long-term, alternating trophic group trends, from rare in the tropics ( |
| Document Type: |
article in journal/newspaper |
| File Description: |
Electronic-eCollection; application/pdf |
| Language: |
English |
| ISSN: |
2045-7758 |
| Relation: |
Ecology and Evolution; Ecology and Evolution, 2020, 10, (14), pp. 6954-6966; http://hdl.handle.net/10453/144795 |
| Availability: |
http://hdl.handle.net/10453/144795 |
| Rights: |
info:eu-repo/semantics/openAccess ; This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.© 2020 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd |
| Accession Number: |
edsbas.5EDC7B7E |
| Database: |
BASE |