As summer transitions to winter, there is a similar shift in my work schedule from “field season” to “lab season”. As wildflowers cease blooming and bees stop flying, our work at the research farm becomes low-level maintenance: weeding, mulching, and reseeding bare spots in the interstitial grass.
This provides ample time to dive into the freezer full of samples from the 2017 field season (which have waited patiently for months). There are several hundred small bags, each containing the sampling contents of one plot preserved in ethanol. Because these were taken with an insect vacuum rather than hand netted or trapped, the samples are messy – the vacuum doesn't discriminate between insect, vegetation, or dirt, and sorting through one bag can be time intensive. There is a plus side! Using the vacuum allows us to census all of the insect diversity present on each wildflower species – from bees to bugs, and beetles to spiders.
Sorting these bags involves removing large specimens (like bees and larger beetles) to pin separately, then pouring the contents of the sample bag into a wide petri dish. Under a dissecting scope, I can then ID smaller specimens and remove them from the inevitable dirt clumps and plant detritus. How long does this take? It depends on the flower species the sample was taken on and the time of year it was collected. Unsurprisingly, mid-summer samples tend to have more insects than early and late season samples; one summer sample contained 86 thrips alone!
Bees are treated differently. Most specimens are pulled from the ethanol and allowed to dry before pinning (or “pointing” for the very small species). Bumblebees, however, are so hairy that they need to be styled before being curated. I rinse each bumblebee, dry it with a hair blower, and then I fluff the hairs using a fine-tipped paintbrush to ensure they don’t clump (who knew the lab would moonlight as a Bombus spa!).
This process has taken most of the winter, and I have plenty of sample bags remaining. It seems fitting that I published this post today, as yesterday two of my Fragaria vesca plots began to bloom, kicking off the beginning of this field season! In the meantime, I’ll keep pinning away, trying to make room for the 2018 samples in the freezer.