What the flock? Gulls take over lawns, hoover up scourge of Winnipeg worms
Bryce Hoye | CBC News | Posted: June 20, 2017 3:36 PM | Last Updated: June 20, 2017
Birds get wise, leave water behind for smorgasbord of forest tent caterpillars, elm spanworms, cankerworms
They're the bane of cyclists' existence and leave smears across vehicle windshields, but now a scourge of worms that has been eating its way through Winnipeg treetops has met a formidable winged foe.
Gulls usually stick to the water, but they recently wised up to an infestation of three different worm species in Assiniboine River-adjacent Wolseley and West Broadway. Flocks of the white birds have begun waddling across area sidewalks and lawns in search of squishy meals.
"Doing what they're doing, it's pretty unusual,'" said Paula Grieef, a naturalist at Oak Hammock Marsh.
The first wave of forest-tent caterpillars in May was followed closely by elm spanworms and cankerworms. The wriggling trio has hung from treetops and scattered droppings on the ground below.
The birds have hopped from street to street and stopped on Palmerston Avenue and Spence Street this week to chow down.
Grieef said it's likely one or two gulls first discovered the worms and couldn't keep the smorgasbord a secret for long.
"Gulls are one of those kinds of birds that will eat just about anything and take advantage of whatever is available," Grieef said. "I would think lots of little birds are eating them, but we don't notice them like we would notice the gulls."
Grieef said the birds will help bring the overall worm number down but can't single-wingedly exterminate the pests.
Winnipeg is in the midst of its worst elm spanworm invasion in 20 years, the city's insect control branch says. The city expects the invasion to last another two to three weeks.
Elm spanworms that evade the gulls will morph into pale white moths this August, while cankerworms will turn into grey moths. Taz Stuart with pest-control company Poulin's said last week that forest tent caterpillars will take on a golden-brown colour in their moth phase in July.
City crews sprayed for worms from The Forks west through West Broadway and Wolseley on the weekend.