Show #27/8101. The Symbiosis Between Pollinators And Flowers

Every Butterfly Needs A Host Plant

Every butterfly has its own specific host plant. The monarch butterflies only use milkweed. Eric concludes, as gardeners if we want to help the monarchs out then plant some Asclepias in our garden. But we can't just plant any milkweed, right? That is a good point because there are 100’s of different species of milkweed in North America, all native. If you go to your local garden center, sometimes what you'll find is a non-native species of milkweed, a plant that's non-native to your area. Some are being brought up from Central America, some are coming from Africa. We have to make sure we're getting a native species for our garden because the monarchs have evolved to live with those native species. The non-native milkweeds can actually interfere with the monarch's migration because they stay in leaf longer than they should and that actually confuses the monarch and tells them it's not time to migrate, when it actually is.

Eric knows Dr. Andy studies a lot of fascinating things, and one of the more interesting aspects of his education and research is with parasites that also affect these insects. Eric knows there's an issue with a non-native milkweed that's related to parasite populations that affect monarchs. Dr. Andy concurs, there is a parasite that lives on monarchs. It's probably a naturally evolved parasite. All monarch populations around the world have this parasite to some degree. In places where they don't migrate, like in South Florida, their parasite levels are really, really high. They think that the migration itself actually cleanses the entire population of diseased individuals because it's such a long distance flight,