Scientific support for tagging!
for immediate release
Scientific support for tagging!
Scientists are showing their support for tagging. Over the next few months, Monarch Butterfly NZ Trust volunteers will apply small white, coded labels to the hindwings of Monarch butterflies soon after they emerge from their chrysalis.
“By tagging and following Monarchs, we can use them as indicators of the status of our environment here in NZ,” said Dr Mark Hauber, who works in the field of Ecology, Evolution and Behaviour at the University of Auckland’s Biological Sciences.
“Tagging and observing butterflies also serves a scientific purpose,” he continued. “This is not simply by collecting critical data, but also by introducing people to the method and purpose of scientific investigation.”
Monarch butterflies are already recognised as indicators of environmental health in North America.
The butterflies typically form large clusters, sometimes containing hundreds or thousands of butterflies, on trees in well-sheltered areas during the colder winter months.
In the 1970s and 80s there was a large overwintering site at Butterfly Bay, near Kaeo in the Far North. An investigation in the winter of 2006 found only seven Monarchs had come back to the site. This has caused some concern; what is happening to NZ’s insects?
More than 50 per cent of the world's wildlife is made up of insects. Their numbers and shifts in life cycle are an excellent indicator of the general health of the environment.
And of course the easiest insects to look for and count are butterflies – with the bright orange colour and comparative size of the Monarch adding to its suitability for this exercise.
“Unlike in North America, preliminary investigations in NZ show that Monarchs move north, perhaps to escape the cold,” continued Dr Hauber. “Is this really true? Are overwintering aggregations of Monarchs different from their counterparts in North America?”
“If so, have these animals evolved to adapt to the NZ environment?”
These are some of the questions that the Monarch Butterfly NZ Trust hopes to answer – with the help of citizen scientists throughout the country.
When sighted, Monarchs may be taking nectar from flowers, or flying in a certain direction.
“This is important,” said Jacqui Knight, spokesperson for the MBNZT. “We need to find out where the Monarchs cluster in their overwintering sites because this late summer generation forms the breeding stock for the next year’s Monarch population.”
“And if anyone sees a tagged Monarch we hope they will tell us the unique code which is on the tag – and let the Monarch continue its journey.”
Professor Barrie Frost, a New Zealander now attached to Queen’s University, Ontario, in the Department of Psychology, congratulated the Monarch Butterfly NZ Trust on their work.
“The Trust is doing an excellent job collecting this data. Their tagging programme should in time reveal if NZ Monarchs also make some attempt to migrate north.”
“They would be heading to overwintering spots with the right microclimate to survive the winter.”
“Monarchs typically cluster most heavily in the same places, even the same trees, year after year,” he said. “So in order to protect next year’s breeding crop we need to show good stewardship and protect these sites.”
In North America nearly all of the Monarchs born east of the Rocky Mountains migrate to a small area in the Central Mexican mountains, some travelling 3500 kilometres from Canada.
“After extensive illegal logging in these protected Mexican sites, the butterflies were put at grave risk,” he said. “Much of their traditional shelter had been removed.”
In 2002 an unusually severe winter storm killed millions of the overwintering Monarchs, which led to reduced populations for a few years. Fortunately the population now seems to have recovered.
“But this demonstrates why we need to find out where they go to overwinter.”
With the help of the NZ public, and especially school children through their teachers bringing the facts of Monarch butterfly ecology to their attention, it should be possible to find and protect these sites, and keep the NZ Monarch population healthy.
“Monarch butterflies are creatures of daylight and colour, very much like humans,” added Dr Hauber. “By learning what is important for them to live and travel safely, perhaps we can also learn a bit more about ourselves too.”