Spatial and temporal patterns in macroherbivore grazing in a multi-species tropical seagrass meadow of the Great Barrier Reef

Scott, Abigail L., York, Paul H., and Rasheed, Michael A. (2021) Spatial and temporal patterns in macroherbivore grazing in a multi-species tropical seagrass meadow of the Great Barrier Reef. Diversity, 13 (1). 12.

PDF (Published Version) - Published Version
Available under License Creative Commons Attribution.

Download (5MB) | Preview
View at Publisher Website:


Macroherbivory is an important process in seagrass meadows worldwide; however, the impact of macroherbivores on seagrasses in the Great Barrier Reef (GBR) has received little attention. We used exclusion cages and seagrass tethering assays to understand how the intensity of macroherbivory varies over space and time in the seagrass meadows around Green Island (Queensland), and what impact this has on overall meadow structure. Rates of macroherbivory were comparatively low, between 0.25–44% of daily seagrass productivity; however, rates were highly variable over a one-year period, and among sites. Loss of seagrass material to macroherbivory was predominantly due to fish; however, urchin herbivory was also taking place. Macroherbivory rates were of insufficient intensity to impact overall meadow structure. No macroherbivory events were identified on video cameras that filmed in the day, indicating that feeding may be occurring infrequently in large shoals, or at night. While relatively low compared to some meadows, seagrass macroherbivory was still an important process at this site. We suggest that in this highly protected area of the GBR, where the ecosystem and food webs remain largely intact, macroherbivory was maintained at a low level and was unlikely to cause the large-scale meadow structuring influence that can be seen in more modified seagrass systems.

Item ID: 65428
Item Type: Article (Research - C1)
ISSN: 1424-2818
Keywords: seagrass ecosystem; herbivore; plant-herbivore interactions; grazing; fish; sea urchin; Marine Protected Area; Great Barrier Reef
Copyright Information: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (
Funders: Ausralian Research Council (ARC), Gladstone Ports Corporation, Holsworth Wildlife Research Endowment (Ecological Society of Australia), National Environment Science Programme Tropical Water Quality Hub, Australian Government Research Training Scholarship
Projects and Grants: Australian Research Council grant LP160100492
Date Deposited: 14 Jan 2021 00:13
FoR Codes: 31 BIOLOGICAL SCIENCES > 3103 Ecology > 310305 Marine and estuarine ecology (incl. marine ichthyology) @ 40%
41 ENVIRONMENTAL SCIENCES > 4102 Ecological applications > 410203 Ecosystem function @ 30%
41 ENVIRONMENTAL SCIENCES > 4102 Ecological applications > 410206 Landscape ecology @ 30%
SEO Codes: 96 ENVIRONMENT > 9608 Flora, Fauna and Biodiversity > 960808 Marine Flora, Fauna and Biodiversity @ 100%
Downloads: Total: 890
Last 12 Months: 91
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page