Armed with my camera at a time that no self-respecting wildlife photographer should be active, I wandered around the garden at midday. Lunchtime wombles at work are a favourite pastime; birds are dozing in the shady canopy, some of them muttering quietly, while heat-activated insects hold sway in the sunshine.
Sudden movement caught my eye, but it took a few seconds to work out what I was seeing. A female jumping spider (Hyllus argyrotoxus) had captured a long-horned grasshopper nymph that was almost perfectly camouflaged against a stalk of signal grass. With a web thread anchoring her to safety, she was in the throes of subduing her prey. Fascinated by this miniature drama (despite feeling sorry for the grasshopper), I edged closer to get some photos.
Not three minutes later, when the spider was fully engrossed in her meal, a diminutive male spider entered stage left. With alternating short jumps, pauses and tiptoeing walks, he eased towards the female, eyes trained intently on her.
This was no direct approach; he followed contoured leaves and kept a constant distance of several centimetres.
At intervals, he stopped and extended a foreleg in what looked like a symbol of yearning but was probably a gauge of distance. A leap across space brought him closer. Oblivious to her suitor, the female continued to feed.
Once the male had navigated to an outlook above the female, he once again calculated his next move. Eventually, he cautiously abseiled towards her, legs outstretched and silk firmly attached to his lofty belay point.
Slowly and cautiously, he approached her from behind.
With forelegs outstretched, he tentatively tapped her legs and abdomen. I can’t speak for the male spider, but I, for one, was holding my breath, half expecting a sudden whip-around and lethal attack. Although the anticipated reaction didn’t come, the male retreated. What signal he had received that she was not ready was not visible to me.
He returned and tapped her again. This time, she didn’t move when he tapped her legs and abdomen. Tap-tap-wait... Tap, tap, wait...
He seemed to receive the correct feedback from the female, so he climbed onto her back. When he got to her cephalothorax, he turned fully around.
By now, she appeared to be receptive, leaving a gap between her abdomen and the grass inflorescence. With hard-wired ease, the male ducked under her legs and, using his pedipalps, deposited his spermatophore in the female’s epigynum. Several seconds later, he beat a hasty retreat, leaping away, before his mate changed her mind about only wanting grasshopper for lunch!
The entire process took around 15 minutes. And I might’ve missed it all if I’d not noticed the movement of the huntress in the grass. It’s a clear reminder that not all photos need to be taken in the golden hour, so carry a camera always and check the bushes for interesting stories!
The science behind the behaviour.
Jumping spiders are among the most "popular" spiders, in part because of their appealing forward-facing eyes and in part because of the well-documented mating dances by the male "dandies." However, not all courtship involves the dances, as illustrated in this photo-story.
Scientists have noticed that the elaborate dance displays - where males wave their pedipalps in specific patterns to signal to the female that they are of her species and should not be regarded as food - tend to happen in the open.
If, as in this case, the female is otherwise occupied, males may move in for "sneak copulations". Even then, to avoid becoming lunch, the male will check a female's receptiveness by tapping her with a certain frequency. Hairs on her legs (trichobothria) detect the pattern of vibrations; it's essentially a tactile Morse Code. Only if she is receptive will the female allow the male to mate. In my observations here, he made two or three approaches before he appeared to get the all-clear.
If you’d like to read more about jumping spider courtship, there is plenty of incredible info online. For starters, follow this link for fascinating insights.
[Photos (c) The Rambling Zimbo. Camera body: OM System OM-5 Mk1; Lens M.Zuiko 12-45 f/4 Pro. Post-processing in DXO PhotoLab 8].
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