Crab Spider eats Monarch Caterpillar in Canadian Milkweed Patch

Life (and death) in a milkweed patch
December 28, 2010
Location:  Manitoba Birds Hill Provincial Park, Canada
Hi Daniel:
Every July tens of thousands of people descend on Manitoba’s Birds Hill Provincial Park for one of Canada’s, and North America’s, oldest and largest folk festivals (we haven’t missed it for more than 30 years!). In 2006 I discovered the most impressive milkweed patch I have ever seen, wedged between a parking lot and an oak forest, and was thrilled with the abundant and diverse bug life I found there. To my dismay, however, I then watched the patch get systematically destroyed over the next few days as festival goers heedlessly drove and parked all over the patch in an effort to get closer to the shade provided by the adjacent trees. This is generally a ‘green’ crowd so I think it happened more out of ignorance than callousness, but the result was the same. When the same thing happened in 2007 I decided something needed to be done. So I contacted both park and festival staff to plead my case for the protection of this incredible island of diversity, particularly since it is located in the middle of a provincial park.

Milkweed Patch Saved

When we arrived for the 2008 festival I went straight to the patch and was delighted to see the whole area cordoned off, as it has been every year since. Unfortunately, 2008 was one of our coldest wettest summers in recent memory and the milkweeds were barely knee-high and not flowering. The next year was almost as bad, but in 2010 our glorious summer weather returned and the milkweeds were nearly chest high and flowering profusely – and the bug watching was spectacular! The attached photo of what I believe is a Xysticus punctatus Crab Spider finishing off a hapless Monarch caterpillar is one of my favourites from 2010. The other two photos show the milkweed patch after the 2007 festival, and protected in 2010. If you or any of your readers are interested, I have uploaded a collection of photos taken at this location since 2006 (with more to follow next year, I am sure). I am still working on some of the identifications and I am not certain about some of the ones I have inserted, so any comments or suggestions would be welcomed and appreciated. Regards.  Karl

Crab Spider eats Monarch Caterpillar

Hi Karl,
We love hearing how your conservation activism made a difference.  You did not attach any images, so we took the liberty of lifting a few from your web posting.  We might be interested in posting a few more butterflies and dragonflies if you give permission.  We especially love the Milkweed Meadow as an important and diverse ecosystem, and we recently created a unique tag for postings related to Milkweed.

Crab Spider eats Monarch Caterpillar

Thanks for bailing me out Daniel; I forget my attachments all the time. These were the files I was going to send but I am also fine with what you put up (although I suppose they don’t quite match the text).  Go ahead and borrow anything you like, or let me know if you have anything specific in mind. I have thousands of photos that I have been meaning to organize and perhaps upload, but I just haven’t been able to find the time. Perhaps next year.  Have a great new year! K

Destroyed Milkweed Patch in 2007

Thanks for sending additional images Karl.  We have posted the 2007 image with the mutilated Milkweed Patch to accompany the original posting.  We will let you know if we post any of your other wonderful images.

1 thought on “Crab Spider eats Monarch Caterpillar in Canadian Milkweed Patch”

  1. It’s June 29, 2020 in Hermosa Beach, CA (a few miles south of LAX). I just witnessed some sort of black jumping spider eating a Monarch caterpillar; the spider scurried away before I could capture a cell phone image. Thanks for your info (I discovered after googling). I would never have guessed the butterfly had “such enemies”. I will keep an eye out for future encounters.


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