The Rondeau butterfly count of this past weekend had excellent weather: sunny, not as hot as some days, tolerable humidity and with a slight breeze. As expected, however, the butterfly season has been a bit less diverse than what we used to get, and the questions arise as to why. There are probably a number of factors, including the cool, wet spring which was hard on overwintering butterflies, as well as the ongoing extensive use of pesticides and genetically modified and/or pesticide ready seeds being used which affect many pollinating insect species. But as usual, some species were relatively plentiful and others were noticeable by their absence or at least extremely low numbers.
My area consists of several small patches, some near Erieau at the McGeachy Pond and Rail Trails, as well as roadsides adjacent to woodlots, old fields, etc., in the greater Blenheim area. All of these sites I do on my own, but for a short time in the middle of the day, I meet up with Steve Charbonneau and Keith Burk to do an old field near the sewage lagoons, which is getting a lot shrubbier than it used to be and is not as productive.
Monarch were pleasantly abundant, unlike some years. I had 69.
Red Admirals were widely scattered, with about 15.
Somewhat surprisingly, Cabbage Whites and both sulphurs were not all that common, which is unusual.
I had a single Mourning Cloak.....
.....and a single Question Mark.
While walking along the McGeachy Pond trail, I noticed this little critter feeding and fluttering exactly like a butterfly. It wasn't anything I had ever recalled seeing before, and managed to get a few photos. It wasn't long until I realized it was a day flying moth, and when I got home I determined it was a Spear-marked Black moth.
There were lots of dragonflies, and I stopped to get this photo of a cooperative Eastern Meadowhawk before a bee came along and the dragonfly left.
When Steve, Keith and I checked out the old field near the sewage lagoon, we added a few species to our list. The most unusual one for our day was this Delaware Skipper, which posed very briefly before vaulting itself into the air in typical skipper fashion, never to be seen again.
I continued on my way, checking out various easily accessible spots. One old field looked promising with a lot of milkweed patches. But it turns out they were almost all Prairie Milkweed (
Asclepias sullivantii) and while it looks superficially like Common Milkweed (
Asclepias syriaca), I have often found that Prairie Milkweed is not as effective at attracting butterflies. It doesn't seem to be as aromatic or something. Prairie Milkweed flowers are a bit deeper red in colour, have smooth, hairless leaves which are more upright and often have a dark red mid-vein.
I did manage to get a photo of a Common Wood-nymph. Usually these critters are only seen flitting through the vegetation and when they land they are often in an almost impossible spot to photograph.
I checked out the pollinator garden and grassland area near Canadian Tire, where a good population of grassland birds have been the last few years, such as Dickcissel, Bobolink, Eastern Meadowlark and Savannah Sparrow. The one section has been planted with numerous wildflowers. While there was a good diversity, they weren't at their peak, with only scattered individuals throughout the patch, including the following.
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| Butterfly Milkweed |
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| Large-flowered Coreopsis (not native) |
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| Purple Coneflower (not native) |
As was typical everywhere I stopped, there were a few Monarchs, but not a lot of other butterflies. I was pleased to see a lot of Bobolink, however. I stood in one spot and scanned, counting a total of 16, a mix of adult males and females and probably some of them were young of the year, looking much like the females. Some of the males were starting to lose their predominantly black and white feathering as they transition to their non-breeding plumage.
Another stop was at the B-fit park on the south side of Blenheim. It is a walking trail, a loop of about one kilometre. Inside the loop are two cells, one which is mostly wetland and the other is considerably drier, with a lot of Swamp Milkweed and Dogbane.
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| Swamp Milkweed |
I was hoping for something interesting on the Dogbane, but did not see anything. Again, Monarchs were by far the most common butterfly.
One of the adjacent landowners has a sizeable flower garden right next to the trail. Most species were not native, although they were colourful. But there were a few prairie type species, including Butterfly Milkweed, Purple Coneflower, Black-eyed Susan and one which I was quite surprised to see, Queen-of-the-Prairie (
Filapendula rubra). This is not a species native to Ontario, but is an indicator of a high quality prairie found in the mid-western states of Missouri, Iowa, Illinois, etc. In spite of my many trips to mid-western prairies, I have either been a bit too early, or a bit too late and never seen one in flower. In fact it is considered a somewhat rare and local species even in the mid-west, so I was quite surprised to see it at the edge of Blenheim!
There were several large plants of dill in this garden, and the Summer Azures were quite interested in it.
I ended up with 19 species of butterflies, not too bad considering the overall lack of habitat diversity of my area, and certainly a little lower than some previous years. Regardless, it was a great day to be out!
