Thermoregulation, both behaviorally and physiologically in dragonflies have upper limits and the two heat domes that we have been experiencing this month, keeps most of the species from becoming active and thus noticeable during the hottest part of the day.
So far this July, I visited Patuxent Research Refuge five times during the morning hours before the heat became too much for most dragonflies and me. These were short visits of only three to four hours, always ending around one in the afternoon. These visits
were on July 8th, 10th, 12th, 14th,and 15th. The coverage on the Refuge included the North, Central, and South Tracts. In general, the 2026 trend continues that most species have reduced numbers of individuals this year, probably due to the draught and now
the heat.
The highlight for this month was finding a small population of Blackwater Bluets on the Patuxent River that separates Anne Arundel and Prince Georges Counties. This was a new record not only for the Refuge, but new county records for both Anne Arundel and
Prince Georges Counties. The low water levels of the river due to the draught has allowed me to investigate sections of the river that normally are not accessible and one of these areas was where I located the Blackwater Bluets.
In my tally list below, you will notice that I have recorded 70+ individuals of the Elfin Skimmer. This gives the false impression that the population is doing well. It is not and has taken a nasty hit this year. The reason for the high individual numbers
recorded is due to nearly all the larval habitat drying out and the reproductive adults being concentrated in a few remaining pools left within the normally extensive marsh area which made them easy to count.
The list below is a total of all individuals seen during the five days in the field for the first half of July.
DRAGONFLIES AND DAMSELFLIES SEEN:
Ebony Jewelwings (Calopteryx maculata) – 10+
American Rubyspots (Hetaerina americana) – 6
Swamp Spreadwings (Lestes vigilax) – 3
Slender Spreadwings (Lestes rectangularis) – 2
Elegant Spreadwings (Lestes inequalis) – 2
Blue-fronted Dancers (Argia apicalis) – 3
Powdered Dancers (Argia moesta) – 2
Blue-tipped Dancers (Argia tibialis) -- 22+
Stream Bluets (Enallagma exsulans) – 5
Orange Bluet (Enallagma signatum) – 1
Lilypad Forktails (Ischnura kellicotti) – 6
Fragile Forktails (Ischnura posita) – 56+
Eastern Forktail (Ischnura verticalis) – 1
Black-shouldered Spinylegs (Dromogomphus spinosus) – 2
Common Green Darners (Anax junius) – 3
Fawn Darners (Boyeria vinosa) – 2 adults and 1 cast skin
Cyrano Darners (Nasiaeschna pentacantha) – 3
Prince Baskettail (Epitheca princeps) – 1
Mocha Emerald (Somatochlora linearis) – 1
Banded Pennants (Celithemis fasciata) – 15
Eastern Pondhawks (Erythemis simplicicollis) 62+
Spangled Skimmers (Libellula cyanea) – 32
Widow Skimmers (Libellula luctuosa) – 16
Slaty Skimmers (Libellula incesta) – 128+
Painted Skimmer (Libellula semifasciata) – 1
Common Whitetail (Plathemis lydia) – 27+
Blue Dashers (Pachydiplax longipennis) – 124+
Wandering Glider (Pantala flavescens) – 1
Spot-winged Glider (Pantala hymenaea) – 1
Eastern Amberwings (Perithemis tenera) –3
Autumn Meadowhawk (Sympetrum vicinum) –1
Carolina Saddlebags (Tramea carolina) – 5
Black Saddlebags (Tramea lacerata) – 2
BUTTERFLIES SEEN:
Eastern Tiger Swallowtails – 5
Eastern Tailed Blue – 1
Pearl Crescents – 7
Red-spotted Purples – 14
Great Spangled Fritillaries – 3
Monarchs – 3
Question Mark – 1
Horace’s Duskywings – 9
Wild Indigo Duskywing – 1
Least Skippers – 5
Sachem -- 1
ADDITIONAL PHOTOS THAT MIGHT BE OF INTEREST:
Richard Orr