Monthly Archives: September 2011
As we hiked higher into the mountains, we were able to grasp just how far the fires had spread in Arizona. There was a patchy burn pattern over the hills and mountains, extending in all directions.
I wonder what sort of succession will emerge as a result? In a year or two I bet biodiversity will explode. Wildlife was rather sparse this summer because of the fires, but I hope to visit again next year to see how the recovery goes.
Mermelontidae, from Arizona. I’m having a heck of a time trying to identify this guy… any ideas?
I saw overnightprints was having a business card sale, so hey, why not?
Can’t wait to get these in these in the mail!
It took me a while to track down the font from the theme of this blog, but I got it. And of course I had to labor over exactly which photo to use – but I settled on one of my favorite species, Acronicta afflicta. I am a firm believer in keeping cards eye catching and simple. Of course, I will also need to find a way to distribute 500 of these cards, haha. Always handy to have in my purse at least!
This may or may not become a regular thing.
We spend wayyyy too much time in the lab laughing at the caterpillar photos we take (photography is a regular chore around here). What can I say, they are silly creatures. So if we take any that are worthy of captioning, I’ll share.
Of moths, not people, don’t worry.
Dissecting genitalia is one of the skills I learned at the Lep Course in Arizona. One afternoon spent poking at the naughty bits of moths is not enough to become an expert, but I’ll get plenty more practice for my own research.
We used average-sized moths, in the genus Matigramma (family Noctuidae). I’m glad they didn’t have us start on microleps! We had to identify which species we each had by examining the male genitalia. Drawings were offered for comparison (yes, that’s beer at my station, it was in the afternoon!).
I don’t remember all the preparatory steps, but we were given freshly prepared abdomens to work with. We had to brush off all the scales, and carefully pull/cut the genitalia out of the body. In the end, this is what I had:
Though its morphology did not match up perfectly (there can be some natural variation), I determined the best fit was Matigramma emmilta.
If we had to preserve the genitalia, the next step would have been to create a slide. That takes much more time and skill, something I hope to learn soon. I will be doing genitalic dissections for the moths in my group, perhaps they will help sort out some confusing species complexes (or add to the confusion).
Boil them and throw them in alcohol.
(I helped create a line-up of preserved caterpillars for the Lep Course in Arizona. You can see the bagworm (from this post) in the second dish)
I plan to write a few posts about raising and preserving caterpillars soon. I also have some really great “bad hair day” shots of my fuzzier caterpillars. Stay tuned!
Bagworm… what an unfortunate common name. Then again, the bagworm caterpillar is not what most people would consider beautiful. But hey, decide for yourself!
Bagworms are caterpillars in the family Psychidae. They create elaborate cases to protect themselves, while leaving their walking legs free to travel and feed effectively. Case construction varies depending on available materials and their host plant, and the pieces are held together with silk produced by the caterpillar. They can retract into the case when threatened… this particular caterpillar was not very shy, though.
Since we were sacrificing some caterpillars for our research in Arizona, I decided to open up a bagworm case to see how the rest of caterpillar looked.
How strange! What wonderful construction of the interior of the case, and what a silly looking body. I have seen some smaller bagworm species in the North East (usually not more than a cm long), but they grow them big in the South West.
Crotalus scutulatus – Mojave rattlesnake.
Adorable little rattler found on the road in Arizona. We carefully persuaded it to slither into the grass so it wouldn’t get run over.
Entomologists use a variety of techniques to capture insects. The most well known are butterfly nets, which can be used to scoop up just about anything that moves. Nets can be made with thin mesh, thick mesh, super long poles, baited with pheromone lures, you name it. And then there are pan traps, burlese funnels, malaise traps, sticky traps, bait traps… a nearly endless array of creativity. And one of the best ways to collect insects at night is to let them come to you.
It isn’t fully known why so many insects are attracted to lights, but they are. It may interfere with their navigational systems, and once they’re on the sheet they think it’s day time (so they default to their day time resting behaviors).
Many techniques fall under the umbrella term of “black-lighting”, even if you don’t use an actual black-light. They work quite well (even the ones you find in a party store), but even more powerful are mercury vapor lights (and much more expensive). A light, or combination of lights, are hung in front of a large white sheet, and… that’s it. The waiting begins. The set-up can be elaborate with frames and multiple lights, or as simple as a sheet thrown over a branch with a party light. I personally hang a small black-light from the outdoor light on my back patio, and clothes-pinned a sheet to the siding.
At the research station in Arizona (where the above photo was taken), we had several different black-lighting setups throughout the grounds. Some were closer to the stream, some by the buildings, and some were farther out in the woods. We also traveled to different locations in the forest and the desert and set up black-lights there.
Only certain species are attracted to the lights, and they come at different times of night. Sometimes only one sex comes in, meaning the other sex is virtually unknown or uncommon in collections. And the timing means that you might have to stay up until 3am to get the species you’re looking for. If you’re lucky, it will cooperate and come in before midnight!
What you need to collect insects at night
- Black-light or mercury vapor light, and a power source. This could be an outlet if you’re near a building, a battery, or a generator. Make sure the light you buy is compatible with your power source!
- A white sheet. Anything with patterns or colors will make it difficult to spot insects.
- Ropes and clothes pins. These all depend on where you want to hang your sheet.
- Collecting jar. If you want to keep things alive for observation, any container will do. If you want to kill your specimens, use a cyanide kill jar or a plaster jar charged with ethyl acetate (you can also put a jar of insects in the freezer). Keeping a bit of tissue or paper in the container will prevent the insects from running around.
- Headlamp or flashlight. You’re outside at night, after all.
- Hang the light away from the sheet. A few inches to a foot away is ideal. This prevents your sheet from overheating and allows for more reflection on the sheet.
- Keep the sheet steady against the wind. Hold down the bottom with rocks, and generally stay out of windy areas.
- Many types of equipment can be bought through BioQuip. If you’re looking for cheaper materials, try Amazon.
- Only collect where it’s legal. Ask for permission to use land, and get collecting permits when needed.
- Consider the time of year. Things are winding down here in the North East, but you need to figure out when your target species will be out and about.
- Be patient! It’s good to go black-lighting with friends (and maybe alcoholic beverages).
A cute little mantisfly on a sheet in Arizona.