Project 1.1.3 - Condition, trend and risk in coastal habitats:  Seagrass indicators, distribution and thresholds of potential concern

Project Leaders and Host Organisations

Associate Professor Michelle Waycott (James Cook University)
Dr Len McKenzie (Queensland Department of Employment, Economic Development and Innovation)

Project Description and Objectives

For detailed descriptions of the outputs for this project for Year 4 (2009/2010) of the MTSRF Research Programme, see the Annual Research Plan.

The components of this project will deliver cost effective research and assessment of the region's seagrasses, including assessment of the threats from human impacts to be coupled against findings from Objective (a) (see ARP) of this project to improve knowledge of the distribution of seagrass habitats. The project has strong links to the threatened species theme as these seagrass habitats provide a key food resource for the nationally threatened species of marine turtles and dugong. Outputs of the project will have a strong spatial component including production of GIS layers. A research objective (partly experimental and recommended by the MTSRF Great Barrier Reef Steering Committee) to generate a better understanding of the drivers of seagrass change is included in the information presented here.

The fifteen species of seagrasses occurring in the GBR can be found in estuaries/inlets, along coasts, in lagoons and reef platforms growing in intertidal, subtidal, and deep-water environments (Carruthers et al. 2002). The greatest meadow area is found in estuarine and coastal waters and these are the most at risk from both point and diffuse sources of human-related impacts (Carruthers et al. 2002). Although gaps in our knowledge of seagrass distribution do still remain, these distributions have been relatively well described. These mapping efforts, combined with ongoing community engagement and monitoring (Seagrass-Watch), focus of Objective (a) of this project) have highlighted that seagrass meadows are ephemeral; they come and go on time-scales of months to years (www.seagrasswatch.org; Coles et al. 2007; Waycott et al. 2005). In other regions, fluctuations in seagrass distribution and biomass have been observed with seasonal fluctuations in temperature, light and nutrient availability (Alcoverro et al. 1997; Dunton 1994; Moore et al. 1997; Perez 1992). However, the interrelationship between human mediated influences and normal population changes in seagrass distribution in the GBR are poorly understood (e.g. Inglis 2000). The objectives described here will address questions that will enhance our understanding.

Seagrass-Watch is the largest scientific, non-destructive, seagrass assessment and monitoring program in the world.  Since 1998, when the program commenced operations in Australia, Seagrass-Watch has now expanded internationally to eighteen countries.  Monitoring is currently occurring at over 205 sites.  Seagrass-Watch involves many MTSRF researchers.

Further information is available at the Seagrass-Watch website.  Seagrass-Watch newsletters can be downloaded here.