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Monarch Caterpillar, Here’s Hoping You Make it to Mexico

monarch caterpillar sept 2016_cleanedI was delighted to find this monarch caterpillar in our garden today, munching away on some Common Milkweed (Asclepias syriaca).

We used to see monarchs on a regular basis, but in the last few years these visitors have become very rare in my wildlife garden. My own anecdotal observations match what scientists who study these beautiful orange, black and white insects are seeing across the continent: monarch numbers are alarmingly low.

Some wonder if the species is close to disappearing entirely from our landscapes.

For years I’ve been participating in the Journey North citizen science project by diligently reporting my sightings. As the Journey North website explains, early fall is the peak season for monarchs here in the East. Their numbers are at their highest. (To learn more you can also check out the excellent Monarch Watch website.)

It seems very likely that the caterpillar I found this weekend will attempt the arduous journey down to Mexico, where it will hopefully winter over with millions of other butterflies in a forest high in the mountains. The incredible details of this amazing trip, taken each fall by a new group of butterflies, always amaze me.

For years scientists have been warning that many of the same practices and pesticides used in our American farm fields are threatening this species, in addition to illegal logging in Mexico.

This year I fear that the inspiring and lovely monarchs will face a whole new round of hurdles in the form of mosquito spraying to prevent the spread of the Zika virus. Like the bees described in this sad article from the Washington Post earlier this week, butterflies are very vulnerable to pesticides, particularly the broad-spectrum types being used by both municipalities and homeowners in increasing numbers.

 

4 Thoughts on “Monarch Caterpillar, Here’s Hoping You Make it to Mexico

  1. Have been bringing in Monarch eggs from the garden for the last 3 years, since about 8% of eggs survive predation from ants/spiders etc. On fourth batch since March- ours west of the rockies, will travel north- they overwinter in CA. This year, so far about 35 have fledged from my studio- and we find others on the milkweed that manage on their own!
    Wish more nurseries sold native asclepia, and that people hoping to help the monarchs by planting it, knew that they need quite a lot, or mature plants to sustain the ravenous caterpillars. If the caterpillars eat their entire single plant, they’ll die since milkweed is their only food. Also be careful becuz some states require nurseries to spray milkweed to prevent spread of a particular moth pest. plants should be exposed to sunlight and hosed off for awhile before offered . Around here, there will often be a label saying the plants are NOT sprayed with neonicitoids (sp?)

    • Alison Gillespie on September 26, 2016 at 9:34 am said:

      Your comment reveals that there many similarities and some differences between the CA/West Coast monarchs and those here along the Eastern seaboard. It is easy to find asclepias varieties that are native to the Mid-Atlantic at nurseries here. Most of what you find is the kind that seems least likely to be used by the monarchs in the caterpillar stage, though. For instance, it is easy to find Asclepias tuberosa, known as Butterfly Weed. It is one of my favorite natives. Easy to grow, and very valuable to all types of bees and nectaring butterflies. But not used so widely by monarch caterpillars. It is very hard to find Asclepias syriaca at a nursery. Friends and garden club members in my area will often swap seeds for it. But it is devilishly hard to germinate. I was lucky… some just appeared one day in the forgotten part of my yard. Since then I’ve been collecting the seeds and swapping them out as much as possible. If you check the rest of this blog you’ll see I’ve written about that before.

      But labeling here for neonics is almost nonexistent. We’ve had one local nursery say they will avoid them as best they can, but we often are told that is a herculean task because almost all of the plant suppliers use those chemicals, which will of course kill caterpillars that feed on the plants. Not to mention the bee impacts, which we are finding out are much larger than originally anticipated by ag experts.

      I didn’t know about spraying milkweed for a moth pest. That is interesting and I will try to find out more about that. That is not an issue here in the East that I know of…

      This year was a very good year all around for monarchs in the DC area. Many friends were finding the caterpillars, especially late in the season. Many reported seeing them on the Swamp Milkweed plants (that’s Asclepias incarnata for those of you playing along in Latin). This was a nice thing to experience in what has seemed like an otherwise bleak year news-wise. I know the monarchs have a long long way to go to get anywhere close to their totals from just a few years ago, and even ten years ago they were NOT doing well. But I will continue to keep my hopes up.

      Good luck with your windowsill endeavors! Check out the post on Liz Marshall’s similar work here in the DC area… if you use the search box on this blog you’ll find the post I refer to….

  2. We just found a monarch caterpillar on one of our swamp milkweeds today! A first for us so we’re thrilled, especially since like you we haven’t been seeing so many butterflies and this is the first year we’ve had any monarchs. We live in outer Silver Spring, near the Trolley Museum. Using the link from your post I reported it on Journey North.

    • Alison Gillespie on September 7, 2016 at 11:42 am said:

      Very cool! I am so glad to hear it. Also heard from another gardener here in Silver Spring who is seeing caterpillars on her swamp milkweed… which is especially great to hear since I’ve heard many gardeners dismiss this plant as not being a good larval host based on their own anecdotal experience. I think this demands a new post…! Stay tuned! And enjoy your visitors, Jenny.

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