Southern Hairstreak

Some filler for tonight.  I recently wrote an article for the TEA publication Ontario Insects.  It was about my discovery and subsequent observations of the Southern (Northern Oak) Hairstreak a few years ago.  It is included in part below.

A routine outing to look for butterflies turned out to be the discovery of a lifetime.  On 22 June 2008 I made stops at some favourite spots south of Sarnia in Lambton County in search of butterflies.  I was not disappointed, as conditions that year had created an ideal situation for producing an abundance of butterflies and especially for hairstreaks.

My last stop was Reid Conservation Area near Duthill about 35 kilometres south of Sarnia.  Until 2007, this site had been in private hands when it was donated to the St. Clair Conservation Authority.  Some logging had been done and fields cleared over the years, but the property remained a treasure trove of nature that no naturalist had thoroughly explored.  The forested part is predominately oaks, hickories and walnut and some wetland area exists with various sedges.

A short distance from the gate, I found a small open area that was ideal for butterflies.  Indian Hemp (Apocynum cannabinum) was just coming into bloom where I found a few hairstreaks nectaring on the flowers.  I recognized Banded, but unknowingly I had also photographed  Satyrium favonius ontario, known as the Southern Hairstreak and formerly Northern Oak.

When I arrived home I uploaded my photos onto the computer for processing.  Something did not look quite right for Banded Hairstreak in several of the photos.  I consulted reference material and field guides and thought for sure looked like the Southern Hairstreak.  I was hesitant to believe it since this species was not known to reside in Canada!

I sent off some emails, photo included, and it was not until the evening of 22 June that I received some replies.  My initial query was to Rayfield Pye, who then forwarded my message to Bob Yukich and Colin Jones.  Both Bob and Colin immediately responded by confirming that I had indeed found Southern Hairstreak!  Others also confirmed the find in the flurry of emails that ensued, and as one put it, I had found the holy grail of hairstreaks.

On 22 June 2008 I had seen at least three individuals.  There was little doubt that I had found a colony of the species with the multiple individuals present in suitable habitat.  I went out almost every day following my discovery, taking many photographs.  Table one illustrates my findings in the first year after the initial discovery.

Table 1. 2008 Observations by Blake A. Mann
DATE	NUMBER	NOTES
23 June (5 p.m.)	2	1 very worn; 1 fresh
24 June (5 p.m.)	8	7 rather fresh
26 June (5 p.m.)	10	Females outnumbered males; males chasing females; overcast
27 June (noon)	7	Photos taken
28 June (5 p.m.)	6
29 June (early morning)	2	Very wet
1 July	10
4 July (late p.m.)	6	worn to very worn; one being predated by spider-collected
5 July (early p.m.)	6 or 7	Quite worn; one with white post median spots instead of orange
9 July	1	Very worn

Adding to this initial discovery, on 29 June I found a Southern Hairstreak at Moore Wildlife Management Area on Bickford Line more than ten kilometres to the northeast!  On 5 July, I again checked the Moore site and found yet another individual.  Both were photographed.  This led me to the belief that a smaller colony existed there, perhaps only temporarily.  I have never found one there since although suitable habitat still exists.

With the word out, interested parties came to Reid CA for the hairstreak.  The year 2008 seemed to be a banner year for hairstreaks in general as they were extremely numerous.  Diligent checking since the year 2008 has revealed nowhere near the number of Southern Hairstreaks seen that summer.   Table two summarizes observations to show numbers in subsequent years.  Most were photographed.  In 2012 I did not find any despite extensive searching.

Table 2. Observations 2009-2013
Year	Date	Number	Notes	Observer(s)
2009
	27 June	1		Blake A. Mann (BAM), John Lamey
	4 July	1		BAM
	10 July	1	Very worn	BAM Very worn
2010
	20 June	1		BAM
	25 June	2	One very worn	BAM
2011
	30 June	2	fresh	BAM
	1 July	1		Paul D. Carter
	3 July	1		BAM; Bruce Ripley
	3 July	1		Brenda Kulon, Bruce Ripley
2012	Poor year for hairstreaks!
	26 June	3 or 4		Paul D. Carter
2013	Very poor year for hairstreaks!
	26 June	1	photographed	BAM
	29 June	1	photographed	BAM

Previous to my discovery, there were only three verified records for Ontario.   All were considered strays.  The type specimen for ontario as listed in various sources, was found in July 1868 at Port Stanley, Elgin.

On 14 June 1999 one worn male was found on the west side of Point Pelee National Park Tip, Essex  (Henrietta T. O’Neill, Alan Wormington).

Information provided by Paul D. Pratt includes a specimen 2 June 2005 collected at LaSalle, Essex (Michael Gurr). 

On 4 July 2009, one was photographed at Brunet Park, LaSalle, Essex by Jeffery Larson et al.  Considering the previous 2005 record not far from this location, it has been speculated that perhaps a small colony resides in the area.  Extensive suitable habitat exists in the area.

Ideal habitat exists at Reid Conservation Area with several species of oak.  Nectaring plants are abundant with stands of Indian Hemp and milkweed along the forest edge.  Both Swamp Milkweed (Asclepsia incarnata) and Common Milkweed (Asclepsia syriaca) are present as well.

The Southern Hairstreak is often difficult to find.  It tends to nectar only briefly before disappearing.  One can search several days in a row and not find it or on any given day, one can search all day long and not see it!  There is only a narrow window of opportunity to see the butterfly (adult stage) which is approximately from 20 June to 10 July based on my records.  Weather, of course, can play a factor in which the species may appear later in certain years, or numbers can be reduced.

The Southern Hairstreak (ontario subspecies) was lumped with its southern counterpart sometime in the late 1980’s and according to various literature has apparently never been abundant even where it is regularly found in the northern United States.    The more common southern subspecies is markedly different than Ontario and intergrades do exist in the southeastern States.  According to a search on the internet, nearby Michigan officially has only two known records (Lenawee County, 1975 and Grosse Isle, 29 June 2008).