The courtship behaviour of the silver-washed fritillary, Argynnis paphia (Heliconiinae, Argynnini), is described in most books or websites about butterflies. Here’s how I described it in my book on Courtship and mating in butterflies.
The male …. performs a unique pursuit flight, swooping down beneath the female, then darting up in front of her, until he is positioned above, and slightly behind her. The male repeats this behaviour, swooping down and darting up in front of her several times, presumably stimulating her visually and chemically, via the release of his male pheromone (Cannon, 2019).
Similar descriptions are given on many butterfly websites, such as here, here, and here. There are however, few if any photographs (or videos) of this aerial behaviour. At least I have not been able to find any on Google Images. Perhaps we should not be surprised, as these butterflies fly very fast and it is difficult to capture images of them in flight, as I will show below.
The German ethologist Dietrich Magnus carried out detailed studies on the behaviour of silver-washed (SW) fritillary butterflies, Argynnis paphia, over 70 years ago (Magnus, 1950). The diagrams he produced of the male SW fritillary (below) swooping down, and then darting up in front of the flying female, have been copied many times and appear in a number of books.
The key element of this behaviour is the sudden, upward flight of the male, right in front of the female. The purpose of this behaviour is to brush the female’s antennae with the scent glands on the forewings of the male (below). The androconia are arranged in four, black, parallel stripes in the centre of the wing.
The wings of the female look rather different (below) and lack the pheromone-producing glands of course.
Whilst I was photographing these fast-moving butterflies recently (in Fermyn Woods, Northamptonshire), just trying to get a decent shot, I saw a pair fly past in what was clearly a courtship flight. Luckily, I was in a position where I could click off a few shots as they zoomed by! There was no time to compose the shots and the butterflies were still rather too far away, but nevertheless, I did manage to get a few images of this behaviour. The photographs are not very good! And they are heavily copped. But they are at least a start, and maybe a reader (or I myself) can do better next year!
The first one shows the male flying behind the female (below).
The next shot show the male closely approaching the female (before swooping down below her).
The final shot is very blurred, but it does actually capture the moment the male has darted up in front of the female (below), clearly showing that he makes contact with her.
Well OK! It’s not going to win any prizes! But capturing butterfly behaviour in the field is not easy. Perhaps I should have had the camera on video; then, perhaps I would have captured the whole sequence? However, I could just as easily have missed it completely. The secret to capturing this sort of behaviour is to position yourself in the right spot, and then just wait!
Anyway, I was very happy, overjoyed in fact, to have actually captured this behaviour, even though it is a very grainy and fuzzy image! Perhaps some readers may have better images? That would be great.
Bastock, M. (1967). Courtship: a zoological study (Vol. 4). Transaction Publishers.
Cannon, R. J. (2019). Courtship and Mating in Butterflies. CABI. (https://books.google.co.uk/books/about/Courtship_and_Mating_in_Butterflies.html?id=XwHyxgEACAAJ&redir_esc=y)
Magnus, D. (1950). Beobachtungen zur Balz und Eiablage des Kaisermantels Argynnis paphia L.(Lep., Nymphalidae) 1. Zeitschrift für Tierpsychologie, 7(3), 435-449