Leijpark013

@leijpark013 · 15 Jul 2023

Follow Following

Leijpark 013 Brown sand eye

Written by Thierry P. Thijens ·
In the summer, a butterfly lives in the Leijpark, which often comes out as the winner in butterfly counts. They are counted among the bushes and yet it is not the most numerous butterfly in our country. How does that work exactly?
First of all: We're talking about the Brown Sand Eye. Butterfly counts are searched in various areas: from garden to field, from grassland to park. Especially in areas where there is tall grass, the Brown Sand Eye is found in large numbers; there can sometimes be up to a thousand butterflies on one hectare. But: only there. Cabbage whites are everywhere, which is why they are (usually) the most numerous butterflies.
Back to the Brown Sand Eye. Her green caterpillars, which are rarely seen, feed on all kinds of grasses and will overwinter in a pool of grass in the cold period, only to pupate into adults next June. Once they have crawled out of the cocoon as butterflies, the females mate on their first day. Sex education is not included. The males emit a scent that is irresistible to the new females. For a person's nose, this scent is still best compared to the musty smell of an old cigar box. It's just what gets you excited, isn't it?
The males defend their territory fiercely. Other males are fought and a male is often mistaken; he just as easily attacks barren brown leaves that he suspects are another male. Prevention is better than cure, isn't it?
And then, when the females are fertilized and carry eggs, they begin to behave strangely. Some females fly to a grass stalk, land on it and lay an egg on top of the stem. That is still quite common. But many females take a different approach. They fly over the area full of tall grasses and shoot their eggs randomly into the grassland, hoping that they will end up on a stem or leaf! That also happens sometimes, but many eggs land on the ground. That seems very indifferent, right?
Why they do this is not entirely clear, but the butterflies may not want to risk landing somewhere between the tall stems and being surrounded by grass stalks while laying the eggs themselves, where they find it difficult to see an enemy coming. On top of a stem, the butterflies still have an overview, but much less between them. And shooting randomly in a dense field always pays off. Perhaps this is also why they fly so massively on the same piece of grassland (like salmon lay their eggs all in the same stretch of river): large numbers are more likely to survive than an egg randomly here and there. Reality tells us that the Brown Sandeye is a successful species to this day, so its strategy seems to be working.
The adult butterflies love flowering thistles and, fortunately, there are plenty of them in the Leijpark.
The Brown Sand Eye, a strange guy with her own way of bringing her children into the world, but as long as it works, commenting on this makes no sense.
Now that there are few butterflies (experts are even talking about a disaster year), it's nice that Henk de Winter was able to conjure this beautiful butterfly in front of the lens. The Brown Sand Eye and our Leijpark photographer are somewhat in common; where the Brown Sand Eye shoots eggs, Henk de Winter shoots pictures. On both sides, let's keep it that way.