Water Ribbons – weaving their magic in wetlands and waterways

Australia’s wetlands are home to a remarkable array of aquatic plants, many of which are uniquely adapted to thrive in diverse and challenging environments. Amongst the most common are the fascinating species included in the Cycnogeton genus – the water-ribbons. Formerly classified as Triglochin, water-ribbons are found in all Australian states and are particularly common in the freshwater wetlands and waterways of the southern states.

There are eight species in Australia but the most common and widespread is the Common Water-ribbon (Cycnogeton procerum) which is a beautiful perennial flowering plant that grows in freshwater wetlands, creeks and rivers right across southern Australia.

The plant is characterised by its long (up to 2 m), slender, ribbon-like leaves that often extend above the water, or trail along the surface of the water, giving the plant its common name.

Because this particular species is so common it perhaps doesn’t receive the same amount of attention as some of our rarer aquatic plants, but at NGT I think it would be fair to say we are big fans. Let’s have a look at why.

Survival of the fittest

Many aquatic plants are highly adapted, one way or another, to survive both prolonged drought and seasonal fluctuations in water levels and water quality, very sensible in Australia where dry conditions can always be relied upon. But, Common Water-ribbons take this adaptability to the next level. The plant demonstrates a remarkable ability to adapt its growth and structure in response to environmental conditions. In fact, researchers comparing the plasticity (or adaptability) of Cycnogeton procerum to other common perennial aquatic species – Phragmites and Typha – were surprised to discover that the Cycnogeton was able to respond much most effectively than the other species to changing water levels and nutrient conditions by quickly directing more biomass to their extensive root and rhizome systems. This, when you think about it, is pretty advanced forward planning for a plant. This plant, more than most, can respond so well and so quickly that it is more likely to survive harsh conditions, and live to flower again. Pretty amazing!

Much of the success of water ribbons can be attributed to their extensive rhizome and tuber system, as shown below. Both fruit and tubers are noted in the literature as an important food resource utilised by First Nations peoples.

First responder

This ability to respond quickly to changing conditions is one reason we, at NGT, admire the species. We have long known that water ribbons are one of the first species to respond when the hydrology of a wetland is restored, kick-starting the establishment of aquatic habitat. If you have followed any of our wetland restoration sites over time you will know that the response of wetland plants to restoration is almost immediate when water is added. And, in freshwater systems, water ribbons often appear within months of hydrological restoration. It’s unclear how long the tubers or seed of Common Water-ribbons can remain viable in the soil but given the number of restoration sites it has turned up at that have been dry for a very long time, it is very likely years.

As a fast-responding and robust native species, Cycnogeton procerum plays a vital role in maintaining overall wetland health. Its dense growth also helps stabilise sediments, reduce water turbidity, and contribute to nutrient cycling in aquatic environments.

Ecological Importance

The plant is particularly valuable to native fish and frog species, which use the dense foliage as shelter from the sun and from predators. Small fish, like our native freshwater species of galaxias and pygmy perch, benefit from the microhabitats created by the plant’s structure, which provides shade and protection from predation.

It is no coincidence that in many of the photos on our website where we are monitoring native fish you will notice the telltale signs of water ribbons.

Waterbirds also favour the habitat provided by the plant, as this beautiful image from Mt Burr swamp, captured by Julian Sheahan last year, shows.

Over at Green Swamp, it’s the same story, with Brolga, swans and multitudes of waterfowl enjoying the conditions (not to mention large numbers of frogs!).

Cycnogeton procerum is more than just a pretty common aquatic plant; it is a key player in the health and functionality of Australia’s wetlands. Its elegant form, ecological role, and resilience in the face of environmental challenges make it a symbol of the beauty and importance of wetland ecosystems. By protecting and restoring habitat for our common species, we help to preserve our rich legacy of wetland biodiversity for the future.