About a month ago I wrote a post about pitfall trapping in Pennsylvania. I’ve collected the trap contents a couple times now and thought I’d post a quick update.
First impression: These traps work quite well! I caught a ton of male spiders (my primary target) in the first couple weeks, which must’ve been at the tale end of their wandering phase. The last two weeks produced only a few spiders, thought, and mostly females. Still cool! I also got tons of beetles (Tenebrionidae, Silphidae, Scarabaeidae, Staphylinidae, etc.), ants, some interesting parasitoids (Diapriidae, Platygastroidea, Lagynodinae), millipedes, and many other cool taxa. Each jar was almost completely filled with specimens, which tells me (a) this trap design works well and (b) I have a diverse fauna in my forest.
Here’s the contents of one jar, spread out in a giant Petri dish:
There is so much material, in fact, that I question whether I need so many set up. I don’t know if I can go through 12 of these samples every month and make sure the specimens have some scientific or educational purpose. They’ll definitely be available for ENT 432 students this fall, though!
Adjustments to the preservative: A colleague recommended diluting the propylene glycol-based antifreeze (two parts water, one part antifreeze). I did that for the first set of specimens and found that specimens were not in the best shape after two weeks. Some were on the verge of rotting. 🙁 For the following two weeks I went with full strength antifreeze, which is about 27% propylene glycol. The results were much better, with specimens looking nearly lifelike upon collection. I also ditched the surfactant (biodegradable dish soap) the second time, as it didn’t seem to be needed.
Surprises(!): I’ll try to post some of the surprise or otherwise compelling finds as I sort the samples, but I was very excited to see what look like horsehair worms or nematodes (Mermithidae maybe?) emerging from two of my spiders:
No Mygalomorphae yet, sadly, but there certainly were lots of other cool arthropods in these samples. More soon!
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