It's an invasion of the colourful kind - thousands of monarch butterflies have been gathering in trees in Timaru’s public gardens in their pre-winter ritual.
Photo: Aigantighe Art Gallery
As the weather cools, the butterflies are flocking to cedar trees in the sculpture garden of the city’s Aigantighe Art Gallery.
Jacqui Knight of the Monarch Butterfly Trust says they're preparing to fly to their an over-wintering site.
They’ll be active on warmer days, to “fill themselves up with nectar”.
It’s still not known where they go for the winter, though. “That’s why we’re tagging them, to find out where they go.” They can live up to nine months and the survivors will return in the spring.
The flight to overwinter in warmer places a well-known phenomenon, with one of the largest sites, in Mexico, attracting millions of butterflies which make the 5000km flight from the US and Canada each year.
Monarch butterfly in the forest of Mexico. Photo: AFP / Enrique Castro
The butterflies are attracted to cedar, macrocarpa and pohutukawa trees, where they're believed to leave pheromone signals on the waxy leaves and needles.
Knight is working on a winter habitat in Auckland of macrocarpa trees on a sheltered, sunny, south-facing slope. She’s planting nectar-rich flowers underneath to provide food over winter and early spring. Older flower varieties, single dahlias, zinnias and cosmos are good choices.
Their winter predators are rats and mice, while in summer wasps feed on them.
Knight says there are lots more monarchs than we realise. “There’ll probably be a lot on golf courses - but golfers tend to follow the white ball rather than looking up in the trees and looking for monarch butterflies.”
Check out the Critter of the Week collection on Jesse Mulligan, 1-4pm
The hungry monarch caterpillars
Monarch butterfly caterpillars are struggling to find a feed. Around the country gardening centres and plant shops have sold out of swan plants as people rush to replace the plants which are being… Audio, Gallery
[audio-sb]http://www.radionz.co.nz/national/programmes/afternoons/audio/201848045/expert-feature-monarch-butterflies
