After watching @thebeachcomber 's Advanced Tips for iNaturalist talk, I wanted to share some of my favourite moth demographics charts achieved by annotating observations. @possumpete @stephen169 @dragonette you may also be interested :)

Pasture Day Moth - Apina callisto

The Pasture Day Moth has a really nice distinct split between the larval stage and adult stage. The adults (orange) have a strong peak in April, mating and laying eggs (no observations of eggs yet though!). The caterpillars (blue) start being observed in June and are pretty much all burrowed into the soil to pupate by October (eggs maybe, but I'm not sure we'll ever see any observations of pupae - buried too deep). This is such an interesting species in that the caterpillars are active over winter. I think it also helps that there are plenty of observations of the larvae, likely because they are seasonally abundant, conspicuous and distinctive.

Beautiful Leaf Moth - Gastrophora henricaria

I started annotating this species after seeing several comments by @vicfazio3 on observations that the male (blue) was more frequently observed than the female (orange) - however this may be an artefact of the male's attraction to light, so they are frequently documented at light sheets. If I can figure it out, I'd love to filter the data by day-night and see whether there is still any difference in abundance between the sexes.

Bizarre Looper Moth - Eucyclodes pieroides

To compare with the Beautiful Leaf Moth, I wanted to annotate another geometrid moth with distinct sexual dimorphism, and chose the Bizarre Looper Moth. The males (blue) and females (orange) have relatively similar abundances based on iNaturalist observations, but appear to have shifted peaks in times. The females appear to be slightly more abundant than males early in the year, peak in April and then are less abundant than males in July-August. The males appear to be less abundant than females early in the year, peak in May and are still relatively abundant in August. HOWEVER, I am probably over extrapolating as the sample sizes here are smaller. Also note each of the charts shows total counts rather than relative proportions. Interested to hear other's thoughts and share other interesting charts!

All the above chart screenshots were snipped on 11 September 2021.

Posted on September 10, 2021 03:02 PM by claudiarose