Insects getting jiggy with it

Dagger flies mating (Rhamphomyia sp.).  The female is eating a nuptial gift - a small insect - given to her by the male in order to secure mating rights. The courtship behaviour of the Dagger flies has been much studied and many have elaborate courtship rituals.

In some species competition between females, for these gifts, is so strong that they have evolved ornate features -  feathery scales on their legs, darkened wings, and inflatable abdominal sacs to increase their attractiveness.

Some people say it's much the same with humans - however, I for one, have yet to see an attractive woman with an  inflatable abdominal sac.
My main patch pursuit over recent weeks has been mapping all the warblers, along with the Red Data species of birds. This has involved getting up at first light when song is at its height. First light used to be at reasonable time like 7 o'clock, however the government has seen fit to shift this to the frankly ridiculous time of 4.30.

On a few occasions, though, I have managed to get onto the patch later in the day, to enjoy the recent spell of warm weather.  I have been enthralled to see a bustling, zig-zagging, swarming profusion of insect activity - a lot of it aimed at that perennial favourite - sex.

One of the most obvious insects at this time of year is the St. Mark’s Fly, so-called because they emerge around St Mark’s Day on 25th April.  They are very distinctive with their trailing undercarriage of dangling legs.

Male St. Mark’s Fly (Bibio marci) - left,  and the larger, smaller headed female on the right

The swarms of males, intent on finding a mate are very much in evidence. Interestingly male St. Mark’s Flies have eyes which are divided into two - the lower and bottom parts having separate connections to the brain. The lower part is used to monitor the fly's position above the ground while the upper part scans for prospective mating partners.

Some people  say it's much the same with humans - however, I for one, have yet to see an attractive woman (or indeed any kind of woman) hovering several feet above my head.

Golden Dung Fly (Scathophaga stercoraria) - who doesn't love a Golden Dung Fly.

Predictably, the sperm selection of this species has been much studied. Females may mate with several males, so after copulation each male's sperm is in direct competition to fertilise the eggs. Larger males tend to be more successful as they have longer copulation times and greater rates of sperm displacement.

Some people say it's much the I don't think I'll go there.
After what has been a very poor spring for mothing, things have picked put in  the recent warm weather - this is a Purple thorn

Pine Beauty, Clouded-bordered Brindle, Small Pheonix, 3 more moth species in the garden this week.

Propriety fans will be relieved to know that I don't have any facts about the sordid sex lives of these moths.

A male Orange-tip - my favourite butterfly
Recent Patch Sightings
5/5 - Swift, Spotted Flycatcher, Garden warbler
9/5 - Orange tip, Speckled Wood
11/5 - Young Coot, Mallard, House Sparrow, Starling

1Other scientific terms are available in addition to 'getting jiggy with it', such as 'doing the nasty'. Get this


  1. Great images of the Orange-tip and Purple thorn, and your post gave me some much needed chuckles! And who wouldn't appreciate a present of a dead insect anyway!? ;)

    1. Thanks very much Jan. Yes you'd think a present of a dead insect would be the perfect gift...for birthdays, Christmas but especially Valentine's day...or this could be where I've being going wrong


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