Benefits of Seaweed

5 February 2024

by Madi Turner, Coastal Administration Officer

Storm events in the last few months have increased erosion and sand level changes along with an increase in seagrass and algae (seaweed) washed up on our beaches. This is normal and sand levels will return over time with the seaweed also washing back out to sea.

Seaweed is an important resource providing habitat for a range of animal species that are essential to a healthy beach ecology. It provides food and shelter for scavengers such as amphipods and other invertebrates that consume the debris. Amphipods are a main source of food for shorebirds who forage in the seagrass wrack. When covered by tides, the life in the wrack becomes a food source for marine life. The plant material also returns nutrients/minerals to the beach as it decomposes.

Accumulated seaweed can assist in stabilising eroded beaches as it allows sand and other sediments to accumulate. Given the erosion that has occurred in a few locations recently, this will assist in sand level return.

The appearance or smell may not be pleasant, however there is value in not removing. Removal of seaweed would also require access to the beach with vehicles and machinery which can have negative impacts on our coastal environment

Given the ecological values of the seaweed, it’s importance to maintain the natural decomposition process to ensure healthy food webs to support our broader marine communities.