Urban Walk: The Wildlife of the Royal Canal

A bee hovers along the banks of the canal. It bounces from grass to weed and back again, a faint buzz audible as it lands on the next plant.

Soon, it is drowned by the roar of the daily quad bike brigade and screams of children in wetsuits as they plunge into the algaed waters below. Some people trail dogs. A fleet of cyclists navigates the canal path’s kissing gates towards Drumcondra.

And from under thickets and pondweed, thousands more creatures arrive to make the most of the day. Many come in droves: butterflies, spiders, and ants. Others, like the widowed swan, sit alone.

And some, unless you were looking, you’d never see.

Along the Banks

Since 2000, Tim Clabon has volunteered with the Irish Wildlife Trust, a voluntary organisation established in 1979.

On a recent Monday morning, we stroll a stretch of the 140-kilometre canal, from the local coal burner’s cottages, beyond the sixth lock and back down towards Croke Park.

Completed in 1817 and stretching from Co. Longford to Spencer Dock in Dublin, the waterway supports a rich variety of animal, plant, and insect life, which some people may not have spotted.

The habitats along the Royal Canal can be thought of in three sections, says Clabon.

Firstly, there’s the open water, which supports aquatic creatures and is dominated by aquatic plants such as pondweed, burweed, and Canadian waterweed.

Then there are banks of the canal, the littoral zone, which support emergent vegetation like yellow iris and reeds.

The third section, the towpath verges, supports plants that like to keep their feet drier, such as daisies and vetchling.

“It [the canal] plays an important role as a wildlife corridor,” says Clabon. “And it also plays a role in introducing people to the nature and wildlife on their doorstep.”

The sky is overcast and a slight drizzle begins to fall. Clabon spots two ducks, male and female, edging along the undergrowth of the banks.

“These are tufted ducks,” he says. “They’ll feed on insects and weeds and sleep on the bank.”

Behind a steel fence, next to a long-abandoned railway sleeper, there are dozens of bright red poppies. Among the reeds and weeds along the canal, beetles, ants, and flies scurry about their business, trying their best to avoid birds and other predators.

“There’s a moorhen,” says Clabon excitedly.

The red-beaked waterfowl moves slowly across the water as pondweed floats languidly on the surface.

On the stone walls, lichens and moss grow as meadowsweet and barley grass spring up through the cracks along the path.

A pond skater bounces across the water, as cyclists whizz along the canal on their ways to work.

The Competition

From his backpack, Clabon produces a net and swats the plants along the canal, trapping flies and spiders.

He points out larvae growing along the stem of a waterside plant. He produces a dipping net which he slips into the canal and swirls back and forth for about 10 seconds.

“This one here is larvae, this one looks like a dwarf pond snail,” he says, unloading the catch into a plastic container. “This tiny thing here is a juvenile water lice and this thing here is freshwater shrimp.”

Although no surveys have been conducted as of yet, says Clabon, bats are known to frequent the bushes and trees that lead over the canal walls and down towards the railway line.

A small grey dirt track briefly breaks the vegetation along the bank. It could be otter tracks, he says.

The small semi-aquatic mammals are known to visit the canal and feed on the pike and perch that swim in the waters.

While natural selection reigns over the habitat of the Royal Canal, certain invasive species threaten biodiversity.

Earlier this year, Dublin City Council released the first ever Invasive Alien Species Action Plan, which seeks to identify the most problematic plants along waterways such as the Royal Canal and the Grand Canal.

Japanese knotweed, which Clabon points out along the banks, was introduced ornamentally in the nineteenth century. According to the action plan, its roots can damage infrastructure and crack through concrete, dominating native species and reducing biodiversity.

Canadian waterweed, while not as invasive, lurks under the waters towards Drumcondra and will most likely have to be dredged up at some point, says Clabon.

A family of mute swans sit on the path near the next lock. The parents, who mate for life, guard their young cygnets from potential threats.

As Clabon points out the different plant species along the walls, the cob wards us off. He lunges with his neck, as the female swan, the indifferent pen, tends to the young.

“It’s a myth that they can break an arm though,” says Clabon, dodging the cob’s best effort. “They’re very light, actually, their wings.”

Three weeks ago, seven cygnets hatched. Today, it seems, only three remain.

The urban fox, its den often under nearby residential sheds, skulks at night and claims the cygnets from the canal bank. Loud dogs are dangerous too.

Rats, who follow humans to habitats, are found further down towards Drumcondra. Strong swimmers, they hunt small fish and insects found in the water or along the banks.

And while the various plants provide for butterflies and bees, aphids and ladybirds, human interaction threatens some species moving closer towards urbanity.

Staving off Pollution

Throughout the summer months, despite the council’s plastic bags hooked on fencing along the canal, rubbish lies scattered along the banks and in the waters: beer cans, crisp packets, and six-pack rings.

Mathew Kelly, chairperson of the Royal Canal Amenity Group, has helped promote the Royal Canal as a local amenity since the group’s founding in 1976.

Every second Saturday, community members clear the rubbish in an effort to keep the walkways clean and protect the wildlife from potentially harmful detritus.

“It’s probably improved,” says Kelly. “Initially, in the early 90s, people just used it as a dumping ground.”

Now, Kelly says, more people use the canal to get from A to B or to take a break from busy roads.

But still threats remain. “Plastics and that in the water would affect fish and the habitats in there,” says Kelly. “It would be a major problem.”

Clabon, folding his dipping net back up, points out that balloon plastic is particularly harmful to the many mallards who call the banks home.

And while roach, rudd, and bream can be found in the canal waters, he says, storm drains found along the more built-up parts can cause some pollution.

Crossing over Drumcondra bridge and down towards Croke Park, the vegetation lessens, the paths shrink. Sparsely populated, it’s a stark contrast to the banks only 10 minutes’ walk away.

Here the herons, coots, and kingfishers are less prevalent, the butterflies less at home.

“I think it’s under threat because there’s so much building encroaching upon it in parts,” says Clabon. “Generally the closer to the city you get, the amount of wildlife reduces because of disturbance, habitat-fragmentation and pollution.”

Making our way back towards CrossGuns Bridge, the patches of blue sky have grown. Among the irises and reeds, a cygnet enjoys the company of water boatmen and bumble bees.

It wasn’t a fox this time, it seems, but the fast-flowing water that dragged the cygnet under the bridge. If he can get back safely, that’s four out of seven, not three, still left.