Interesting Observations from the Field (Non-Herps)

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In the course of my work, I spend a lot of time outdoors, and I see a lot of interesting things. I often draw inspiration from encounters I’ve had with snakes or turtles during fieldwork in writing this blog, but this month I wanted to take a different approach. Fascinating observations while doing fieldwork aren’t always related to the animals I’m working with. Instead, I want to highlight a few such sightings that caused me to slow down to observe, admire, or reflect on the natural world. I’ll start with a recent sighting.

Mysterious Marks Along the Streambank

In mid-August I was joined in the field by US Forest Service biologists while doing some general habitat assessments. While walking along a streambank, I noticed some unusual marks on the ground, as if something had dragged its claws backwards across the sand a single time. With no other tracks nearby apart from deer, which don’t have claws, I was left wondering what could have made the markings. Thankfully, a friend, Jonathan Shapiro from the Fox Paw School, is an expert wildlife tracker, so I sent him the photos and asked his opinion. 

His gut instinct was that the markings belonged to a striped skunk. He mentioned that they sometimes make marks like that in defense, to ward off threats and avoid the need to spray. He’d never seen evidence of skunks doing this on the East Coast, so he reached out to a tracker friend of his from out west where the behavior is more common. Leaving very little room to doubt the ID, his friend said: 

“We call this the defensive scrape. The skunk is actually lunging forward and then pushing itself backward, making the scratches, then lunging forward and pulling back. So the scrapes are actually from the animal moving backward after it lunged forward in an attempt to startle a predator or intruder”

The video below shows a skunk using defensive scrapes to ward off a mountain lion:

Fluffy Aphids Disguised as Fungus

Last fall, our Wood Turtle technician, Molly Parren, alerted me to some strange fluffy insects on a stick in the woods. Upon closer examination, they appeared to be some sort of aphid that reminded me of an insect I had almost confused for falling snowflakes a few years prior. After consulting Google and identifying the insect as woolly alder aphids, I looked into them a bit more. The aphids produce a white fluffy wax that disguises their colonies as fungus, making it harder for predators to recognize them. Their colonies are often “farmed” by ants, which eat a sugary substance the aphids produce. In exchange, the ants protect the aphids from predators. Most generations of the aphids are flightless, but when resources are scarce, and at the end of the season, they produce winged offspring that float around in the skies in search of new trees to colonize. While in flight, they can easily be mistaken for snowflakes! 

Swallowtail Butterflies on a Raccoon Carcass

A bit more on the gruesome side, but a few years ago I spotted a group of swallowtail butterflies gathered on a raccoon carcass. I knew the butterflies were doing something called “puddling”, but I didn’t know why, so I looked into it. Male butterflies often gather along the edges of puddles, or sometimes on fresh feces or rotting carcasses. The reason being that they need to lap up liquids rich in salts and other minerals, which they pass along to females during copulation as a sort of nuptial gift that helps increase the likelihood of eggs hatching. I’ll spare you from needing to watch the video I recorded of this behavior, but if you want to learn more about it, you can read my friend Rosemary’s book titled, “Butterflies Are Pretty… Gross.

Interesting observation from the field - swallowtail butterfly on raccoon carcass.
Horsehair Worms

And, to round things out, let’s talk about horsehair worms. I’ve seen horsehair worms a few times during fieldwork, the first being on a trip to a place I call “Snake Island”. The worms were moving slowly through shallow water, and though I’d never seen one before, I was reasonably confident about the ID. 

Horsehair worms are a group of parasites related to nematodes. Larval horsehair worms are eaten by the aquatic larvae of an intermediate insect host. After the larval insect metamorphoses and moves to land, it is then eaten by another insect, which becomes the ultimate host for the worms.

After consuming much of the host’s body, the worm sends a cue to its host to enter water, which prompts the worm to emerge from the host’s body so it can complete its life cycle in the water (reminiscent of the chest-bursting scene from the movie Alien). Remarkably, the hosts sometimes survive! 

Final Thoughts

I could go on about other interesting things I’ve learned from researching non-herp sightings in the field, but I’ll save some for another post. Simply put, nature is amazing, and sometimes gross, and there is practically no limit to the things you can learn by taking the time to research the things you encounter while out in the wild.