I've wanted to start this blog for a while, to share the information that I have been discovering about aspects of our environment from my observations and research.
This first post is about the plight of the Monarch butterfly and it's new and particular peril as it travels though out the Gulf Coast region on it's fall migration to Mexico.
I just a finished a show called FIELD GUIDE, where I raised Monarchs and talked about Migration Interception and the Alien Disrupters - here is the text/research from that show:
ALIEN DISRUPTER = tropical milkweed (Asclepias curassavica) is the non-native plant disrupter of generations of Monarch butterflies during their important fall migration and as a carrier of a harmful disease that has the potential to devastate Monarch populations.
FALL MIGRATION = millions of Monarchs coming from the far North and East travel through the Gulf Coast region on their way to the mountains of Central Mexico where they overwinter and live 5-6 months, instead of the normal 2-6 weeks, keeping their eggs through the winter and releasing them in spring to start the migration cycle North again. This is a once in every 5-6 generation occurrence that happens in the late summer/early fall as they travel down from upper North America.
THE INTERCEPTION = tropical milkweed blooms in zone 8 and below like it’s eternal spring from early spring until a hard freeze, which may or may not occur in the Gulf Coast region, but will certainly occur late winter if it does happen. This unnatural incidence of blooming milkweed in the late fall tricks the migrating Monarchs into breeding instead of keeping their eggs and flying to Mexico to overwinter.
DISEASE = tropical milkweed is a major carrier of the spore borne virus Ophryocystis elektroscirrha, or OE. This appears to be because it can live for so long and therefore so many butterflies and other insects can visit the plant.
PARASITES = the tachinid fly and the tiny trichogramma wasp both lay their eggs on Monarch caterpillars, with the wasp having the ability to lay its egss on Monarch eggs as well, which causes them to die either just before but usually during the pupa (chrysalis) stage. In the case of the tachinid fly, a whitish thread comes down from the pupa and small maggots emerge, which turn into brown pupae and eventually emerge as full adult flies. Monarchs parasitized by wasps will die during the pupa stage and tiny fruit fly sized wasps will emerge.
INTERVENTION = what you can do:
Don’t plant tropical milkweed, plant native milkweeds if any.
Learn to identify native milkweeds and protect them.
Ask local growers to produce native milkweeds.
Plant fall flowers that provide nectar to migrating butterflies (that are not tropical milkweed!).
If you have tropical milkweed or discover it somewhere near you, you can do all or one of the following:
Cut it back several times during the summer – this will help lower the incidence of OE.
AND THEN cut it back from late August through February and keep it cut back until early spring. If it’s in a pot you can move it inside where Monarchs cannot find it.
If you discover it somewhere in late August or early September, cut it down or pull it out.
If you discover it in early October or later, very likely there are Monarch eggs and/or caterpillars on it – if you cut it back then they won’t have food. You can clip the plants and take the cuttings inside to raise the caterpillars, or you can keep the buds and seeds clipped off - but there is nothing you can do otherwise – Monarchs will find it! They will lay their eggs even on the leaf sprouts of an otherwise bare milkweed plant; I have observed this first hand.
The best you can do after early October if you are sure there are no caterpillars on it and the plant looks entirely eaten down, with no sprouts with tiny whitish/pale yellow single eggs on it – is cut it down immediately or pull it out.
PARTIAL LIST OF SOURCES: