The male St Andrew’s cross spider (Argiope keyserlingii, slightly out of focus in the background behind the female) is taking his life in his pedipalps.
This one did all the classic things – stayed behind well back behind the female, plucked on his own thread-within-her-web to get her attention, and dared to draw near while she was occupied feeding. I didn’t see the actual mating. If he was lucky, he would have escaped intact, though this morning there is no sign of him.
According to Australian Geographic magazine 77, Jan-Mar 2005 (on the front cover of which there is a magnificent painting of a female and male), the ‘cross’ pattern on the female’s web reflects ultraviolet light strongly and attracts the flying things (flies, moths, butterflies, bugs, bees, cicadas, insects in general) that are the spider’s prey. To our eyes, it would also seem to attract predators (including spray- or broom-wielding humans) by being so obvious. Another possibility is deterring non-predators by saying what lives there.
There are a lot of the greenish egg sacs of these spiders about at the moment (January). The eggs sacs are apparently attacked by parasitic wasps and flies, and the adults by mantids and birds.
Don’t worry, spiders
I keep house
Kobayashi Issa (1763-1827) (transl. Robert Hass)