Wednesday, July 27, 2022

Addendum to last post: Orchid/moth photo safari

My orchid-pollinating moth rig stands ready. In my last post, I shared photos of the beautiful albeit elfin Small Green Wood Orchid (Platanthera clavellata). As noted in that post, this orchid species has been shown to be largely or at least partially self-pollinating, but insect pollinators surely visit, at least on occasion. At least one known hybrid makes that clear. Well, I couldn't stop thinking about this and was eager to try to see if any moths - the most likely pollinators by far - might visit these orchids. As the pair of plants that I shared in the last post were quite large for this species, and in perfect condition, I decided it was now or never (at least until next year).

So off I went last evening, arriving at the west-central Ohio locale shortly before dusk. Moth pollinators are often crepuscular, visiting flowers at dusk or soon after. See THIS POST for an example of a similar hunt in which I met with success.

The photo above shows my camera rig, set up and ready to fire and affixed to my Gitzo tripod. It is pointed and focused on the orchids, which are near the base of the trees. It's a Canon R5 mated to a Canon 400mm f/2.8 II lens, coupled to a 50mm extension tube. That gets the minimum focus down to about six feet. A Canon 600 speedlite provides illumination, and it's equipped with a Better Beamer flash extender. That unit's fresnel lens magnifies the flash output, allowing light to be thrown further - a necessity when shooting fast shutter speeds in high-speed sync mode. Settings were 1/1000, f/8, and ISO 1000, which gave a good exposure in very dark conditions.

Here's a shot of my target, the lush inflorescence of a Small Green Woodland Orchid. Note the luminescent greenish/whitish/yellowish flowers with greatly elongate nectar spurs. These features strongly suggest moths as pollinators.

Conditions were perfect: absolutely no wind, warm, and humid. As evidence of the stillness, I made the above shot without flash - it was nearly dark - at f/18, ISO 200, and a whopping 13 second exposure. Try that with even the slightest breeze. I generally do not care for the look of flash on flowers. It can impart a harshness not in keeping with the subject's qualities. But when shooting fast-moving moths at flowers, in the dark, flash is essential.

What I would have given to have had a moth in a shot with the orchid. Alas, it was not to be.

A big female fishing spider in the genus Dolomedes was one companion on my nocturnal vigil. She carries her egg sac underneath her body, and the tarantula-sized spider is a formidable defender of her spawn.

As dusk darkened into true night, more creatures of the night emerged. Such vigils, even if "unsuccessful" regarding the goal, are always interesting. Early on I had a moment of hope when some smallish sphinx moth rocketed in and began pollinating nearby Spotted Phlox (Phlox maculata). It got within ten feet of the orchids and I had great hopes it would visit them. No go. As it got darker, ever more moths began flying, but none displayed interest in the orchids.

I packed it in a bit after 10:30 pm, but not before being treated to many interesting creatures of the night. A big old Raccoon came ambling down the trail, got within ten feet of me, and decided to do an about face and reverse course. A pair of Great Horned Owls duetted back and forth at close range, the deeper more resonant hoots of the male alternating with the female's higher pitched hooting. I later saw one of the birds atop a phone pole in my headlights on the way out. A Barred Owl screamed repeatedly at one point, which triggered a classic Who-cooks-you, all! response from its mate. A steady chorus of frog-like chirps came from nearby Northern Mole Crickets. The strange orthopterans are mostly subterranean and even sing from within their burrows. The walk out involved traversing a wet meadow, which was full of the amusingly named Slightly Musical Conehead, their rough "songs" the most conspicuous sound in the damp field.

I don't know if I'll get around to going for moths at Small Green Wood Orchid again. Such a photo would certainly be a challenge. Because of the plant's ability to self-pollinate, perhaps not many insect pollinators visit. Or maybe moths tend to come to the flowers in the wee hours, or just prior to dawn or in the early morning hours, as in THIS CASE. Trying for photos such as this can involve a lot of luck, a lot of time, or more likely a bit of both.

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