Warning: don’t be misled by the title. This post is less of a how-to as a how-it’s-hard-to. It wasn’t click-bait, honest.
I’ll be spending a month in Creston later this year and as with all of my mothing trips I try to do my homework beforehand. The goals are always:
- get a better sense of what species to expect, and
- find good locations to set up sheets/nets.
It’s #2 that’s the biggest challenge. I’ve been scouring Google Maps this afternoon and found some promising spots. But from experience I’m skeptical. The necessary criteria for a good mothing spot are:
- Privacy. You don’t want people stumbling across what you’re doing and interfering with, or swiping your equipment. Forest service roads are usually promising; quiet, discrete parks away from houses are another.
- Proximity to where you’re staying. If you have to drive for an hour to get there, it ain’t so practical. If you’re setting up sheets you have a little more flexibility: for sheets it’s a one-way trip in the evening – you go in and intend to stay. With nets you go in, set up the nets, then go back. Twice the distance, twice the time. You never want a big drive: it means less sleep, or sleeping in and getting late to the nets in the morning. Then the moths are all warm and wigging out and less content to pose for photographs.
- Proximity to parking. Continuation of the previous point. I typically carry a fair bit of gear and I’m almost always alone. So if it means a 2k hike from where you park to where you’re setting up the traps, that’s a problem. It would mean at least 2 round trips. Time, time, time.
- Habitat. Moths are everywhere – and hey, I hear they fly (?) – so any spot that isn’t grotesquely urbanized is likely to have passable habitat and the possibility of moths passing through. But what’s the best spot? What’s the ideal spot to set up a net? This was brought up in a BC Leps meeting a while back and Dave Holden mentioned – admitting its speciousness – that setting up traps in open areas near trees seemed to yield better catches. I’ve found the same. I’ve set up traps in the middle of fields and at the edges and it does seem like having a tree or two nearby helps. Why?1 Of course, too many trees means not enough range + less visibility. So it’s finding the compromise.
Case study: Lillooet
Last year was my first year mothing in Lillooet, so I did my usual routine of hunting around on Google Maps looking for mothing spots beforehand. I found a few promising locations and drove up early in the day to check them out. Despite doing all that prep-work, when I got there I found that 1 spot was far too open to put up nets/sheets (it would be noticed by and upset the people nearby); 2 were on native land and off-limits even to naturalists, and 2 more were a no-go because google maps was out of date. In the end, only 1 spot I’d found online was ok and it took the whole afternoon to find some workable locations.
So yes, finding a spot in a new location can be tough and time-consuming. Go early!
- Why does having a tree nearby help with the catch? Here’s a couple of totally unfounded, un-peer-reviewed theories.
Unfounded theory #1: having anything nearby provides a surface to reflect light. So even though a LepiLED is emitting light at the most alluring radiation bandwidths for moths, it’s intense but small. A nearby tree would reflect that light, enlarging the visible area and the likelihood that a moth with questionable eyesight would see it and be drawn in.
Unfounded theory #2: a lot of moths are mediocre fliers [good contrarian story here about watching a Deilephila elpenor outfly a hungry junco] and need places to rest. Short stints in the air with nearby resting spots. Could they be maybe be initially attracted to a light but en route get preoccupied with finding a place to rest, veer off and pass on by? Could that reduce the overall catch? A nearby tree could provide that resting spot but keep them in the game for being caught.
btw – if anyone knows of actual data about this, please let me know. This is all total speculation.
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BC Moths 