It rained last night and into this morning and the potential for more precipitation loomed in the overcast sky. Despite that, I headed up the slope in the late morning and not surprisingly I did not see much flying at first. I imagine butterflies take refuge in and under vegetation when it rains because a single drop could do a lot of damage. I wondered where hairstreaks tend to roost when it’s raining. Evidently, scrub oak provides adequate shelter because when I tapped some along the trail I flushed out Bandeds, Edwards and a few Striped hairstreaks as usual. They all looked very worn.
As things started to dry, I walked along the trail around the observatory to check out the hairstreak hotspot where I had seen them ‘nectaring’ at scrub oak buds. On the way I found a stand of cherry covered in early instar Cecropia caterpillars (Hyalophora cecropia) – gorgeous yellow creatures with black spines! Our giant silk moth fauna have been experiencing a dramatic decline in the past few decades so it was pleasing to see this healthy cluster. When I got to the ‘hairstreak hotspot’, there were a few, but not many individuals. It was about then that I ran into Greg Dysart, a member of the Mass Butterfly Club, who was also tapping branches and looking for hairstreaks. We teamed up for a while to hunt for butterflies and it proved to be a rewarding partnership. We saw Edward’s, Banded, Striped, and Coral hairstreaks, a few Grays, beautiful Coppers, an American Painted Lady or two, and a very nice Great Spangled Fritillary. Greg also pointed out a lot of the resident odonates to me as well; Ruby Amberwing, 12-Spot, and Blue Dasher to name a few. He told tales of one of his favorites odes, the Dragonhunter, which you can see here: http://dysart.zenfolio.com/anisoptera/h6AC3CE9D#h6ac3ce9d. Greg’s photos are truly gorgeous and I would highly suggest perusing his website.
Cecropia larvae (Hyalophora cecropia).
American Painted Lady (Vanessa virginiensis).
Great Spangled Fritillary (Speyeria cybele).
I started heading down the slope around 4PM and saw a number of Edward’s, Grays, and Banded during my descent. At the bottom of the slope, in back of the red ski rental building I found a tattered hairstreak nectaring on Yarrow. This one actually flew down to the ground and hid in the grass. I followed and photographed, and despite its more tanish coloration, I believe it is just anotherworn Gray Hairstreak. I noticed another Gray on the Wild Indigo (Baptisia sp.) that is now in full bloom. It also dove into the grass instead of flying away – this is a behavior that I have not previously noted. I started walking up the slope that was vibrant yellow with Baptisia flowers and I tapped a Gray HS out of nearly every other stand.
Another worn Gray Hairstreak (Strymon melinus).
Gray Hairstreak (Strymon melinus) on Wild Indigo (Baptisia tinctoria).
White M Hairstreak (Parrhasius m-album)
As I was about to head home, walking through knee high vegetation at the edge of the woods, I kicked up my sixth adult hairstreak species at Great Blue Hill… a White-M (Parrhasius m-album)! It was dazzling and unmistakable and it allowed me to take a few photographs before it took off into the air and perched on a low branch of a white oak tree.
This was a rewarding close to a good day, but despite all the excitement, I have not yet encountered any Oak Hairstreaks at GBH. I know they are here, but I believe the observation is about to close. I will return tomorrow for one final day of searching, but I believe that will be the last day of this season’s field observations for this project.
Oak Hairstreak Study 