Unusual recent observations of ‘boom’ cycles in nature
Have you seen anything unusual lately, like lots and lots of something? There has been an enormous explosion in a range of creatures throughout South Australia, and the following are a bunch of photos and descriptions of each occurrence. Maybe you have seen them too.
High rainfall events triggering emergences or movements of species to areas they don’t normally live/breed is not a new thing.
In the Limestone Coast region in 2010-2012, there was an influx of butterflies not normally seen here. The Chequered Swallow-tail, Small Grass Yellow, and Glasswing to name a few were recorded flying through different part so the region. This phenomena has happened before and you can read more about it here.
However, the current interest in butterfly numbers and movements is coming from the Eyre Peninsula and the mid-north of South Australia, where, after well above-average rainfall, the wildflowers are on their way into bloom, and a massive number of insects have emerged. This fabulous photo below from Cavin Osborn shows exactly what its like in the Flinders at the moment.
Orchid enthusiasts are commenting on how some orchid leaves are visible earlier than normal, presumably as a result of the heavy autumn rains and prolonged humid conditions some parts of the Limestone Coast region experienced in the last two months. This species, pictured below, is no exception, with basal leaves already out for some weeks at two pine forest locations where it is known from.
Flying ants were a feature this week, as our weather was mild to warm and sunny. Did you see them where you live?
These flights are very taxing on the ants, as they only do this once in their lives. Males die shortly after, and females drop their wings, then live underground. Observations of nuptial flights is generally after heavy rain from February to April in the Limestone Coast. But interestingly, from my records, the April flights seem to correspond to dry winters, so let’s see where we land with rainfall over the next few months.
Tiger moths have been extremely abundant this year, and have been reported over large parts of the lower Limestone Coast region in March and April. The larvae feed on lichen growing on the branches of acacias and eucalypts, especially Acacia mearnsii.
This moth is quite a slow flyer and can be close to the ground but generally above head height, up in the canopy of trees and tall shrubs. Presumably, they have proliferated this season due to fewer hot days and wetter summer conditions, but I’m interested to hear from others who may have also observed a higher number this year and share their opinion on why.
Can anyone identify this creature?
They were found on the beach east of Port MacDonnell recently. Millions of them have washed up. iNaturalist has suggest ‘Cunjevoi’ but I’m not convinced this is correct.
