How can I best help monarch butterflies in NZ?

Don’t love your butterflies to death!

Thanks to an excellent study at the School of Biological Sciences, Victoria University of Wellington, we are now better equipped to help monarch butterflies. Early in 2020 Dr Phil Lester and Mariana Bulgarella at the School of Biological Sciences, Victoria University of Wellington investigated how many monarch butterflies in NZ carried the parasite Ophryocystis elektroscirrha, commonly referred to as Oe.

This parasite is part of the monarch’s ecosystem. It’s as much a part of the monarch’s environment as fleas are to a dog. It only infects monarch butterflies and while it can kill or weaken them it harms nothing else. Cells were taken from 408 adult monarchs, from locations between Otago and the Far North. Sampling did not hurt the butterflies.

Surprisingly, almost all butterflies from warmer areas of the country, such as Northland, Auckland, Bay of Plenty and Nelson, carried the parasite Oe.

However, the results from the research raised one very big concern: people trying to ‘save’ sick monarchs, butterflies heavily infested with Oe, or kept in crowded containers or on unhealthy plants.

We urge people who love monarchs to remember they’re wildlife, and not pets. They are cold-blooded and do not ‘suffer’ in the cold. Their wings are waterproof and they can cope with rain. Caterpillars and butterflies know what to do when it’s raining, or windy. They don’t need to be raised indoors or kept warm through the winter. They should be left to do what comes naturally. The fittest will survive and go on to reproduce. It is important that unhealthy butterflies do not reproduce.

Monarchs have been doing just fine without our help for millions of years. While it’s useful to offer some protection against wasps and other predators, the current advice, based on scientific evidence is to raise monarchs in ways that mimic their natural environment. Overcrowded conditions are not seen in nature.

Monarch butterflies, as is everything in Nature, are part of a natural food chain. Not all are destined to become butterflies. Some will feed other species, some will even feed the soil when they die.