Flashy

We were finally blessed with a sunny day today, which brought out a large number of bees, bugs, and hoverflies, but of all the invertebrates I photographed in the garden this afternoon I was happiest to have spotted this tiny Zebra Jumping Spider on the front gate. I was actually looking for a jumper at the time, but more in hope than expectation because according to most authorities their season is just about over, so I gave a little squeak of excitement when I found this one. No wonder the neighbours think I'm odd.

There are three very similar species of Zebra Spiders in the UK, but two are relatively uncommon, and I always assume that the specimens I find in my garden belong to the most common species, Salticus scenicus. In theory the markings on this female are a little too pale, and her abdominal markings are too spotty, but this doesn't change my supposition because S. scenicus is notoriously variable. The only way to tell the three species apart definitively is by microscopic examination of their genitalia, but honestly - I don't care that much.

Salticus scenicus females are about 7mm long, and the males are very slightly smaller. Like other jumping spiders they don't build webs, but stalk their prey and then leap on it, immediately delivering an immobilising bite before settling down to eat it. They're said to be able to jump up to 10cm - that is, about fifteen times their own length - and will tackle prey that's considerably larger than they are. Before jumping they attach a silk thread to the surface on which they're standing, to act as a safety line in case they miss their target; in this case they can either climb up the silk to get back to where they started, or abseil down it to a new location. 

In the past I've watched Zebra Spiders hunting small flies around the honeysuckle on our south-facing yard wall, though the actual pounce is so fast that I've never managed to photograph it, but in this case, sadly, the hunt was over before I arrived, and I didn't get to see the spider spring. The gate is latched back against a different stretch of the same old wall, which is where I suspect that she's living, and I'd be interested to know if she jumped from there, or if she was patrolling the gate in the expectation of a fly settling on the sun-warmed wood. But this will have to be an investigation for another day - should we get any more balmy ones this autumn.

There are a three main problems with photographing Zebra Jumping Spiders. The first is the obvious fact that they can and will jump if you startle them, but I took the time to sidle up to this female slowly and low down, and she was busy enough with her meal to let me get quite close. Which brings me to the second problem: because they're so very small, with a normal 1:1 macro lens you have to be close if you're going to get a reasonable number of pixels on the spider. By the time I took these photos I'd had to remove the lens hood so that it didn't shadow the scene, and I was very much regretting having hesitated over the x2 macro I've lately been thinking of buying. The third problem is to do with the Zebra Spider's brown and white markings, which are produced by iridescent scales that tend to generate unsightly highlights in strong light. I was shooting at f/9 here, but I think it would have been better if I'd stopped down further, to improve the depth of field and sharpen the highlights.

R: C6, D1.