Seagrasses are an important part of many coastal systems, but are also under threat in many areas around the world as a result of habitat loss and reductions in water quality.
Seagrasses are closely related to land plants and are typically restricted to shallow coastal waters where there is
- ample light to support growth
- sandy/muddy bottoms where the roots can take in sufficient nutrients without being up-rooted and washed away by waves and currents.
For food, seagrasses obtain most of their nutrients from the sediments they grow in and have extensive root systems that help reduce erosion and stabilise coastal sediments (which improves water quality).
Meadow-forming seagrasses in Port Phillip Bay and Western Port are dominated by two species:
- long eelgrass
- almost exclusively subtidal (always submerged regardless of the tides)
- growing to a maximum depth of eight metres within Port Phillip Bay.
- short eelgrass
- tends to occur in intertidal and very shallow subtidal habitats,
There is a smaller quantity of a third seagrass, wire weed or sea nymph, which is restricted to the more exposed regions of the bays.

Seagrass is critical to the bays’ health. You can make a direct scientific contribution to the future success of these ecosystem engineers by joining Parks Victoria’s seagrass-specific Sea Search project.
You will need a higher level of skill than some other citizen science tasks but you will learn a lot from the highly skilled Parks Victoria rangers. Quantifying the boundaries of seagrass and its condition will make a significant difference to understanding patterns and impacts that are integral to sustaining seagrass meadows for perpetuity. All Sea Search activities must be conducted with Parks Victoria rangers and permits are required for surveys.