August is a good time to spot spiders on vegetation with their prey, insects, most abundant. One of the most common spiders is the Nursery Web Spider - Pisaura mirabilis which can be found amongst bramble fronds and leaves. It's quite small and feeds on smallish insects which it catches, not in a web but by lurking and sprinting a short distance to catch its prey.
It does make a fantastic web but the purpose is to protect its young as its reactions are fast enough to catch insects directly, usually from the surface of a leaf.
Nursery Web Spider on bramble leaf
The web which it creates in order to protect its eggs and later hatched spiderlings is extremely strong and as can be seen here, a strong twig or bramble frond is used as the basic structure for the 'roof' of the 'tent'. The female spider then sits on the roof of the tent to keep watch and catch food. The bramble leaf is quite small! The adult spider itself when stretched out is only about 14mm long.
Another interesting spider is the Crab spider Misumena vatia. This also waits to ambush its prey but uses its ability to change colour in order to merge with the bright flower it sits on motionless for many hours. It chooses a strong flower normally visited by insects, usually coloured yellow or white then gradually changes its colour to that of the flower petals:
Crab spider on flower petal
This spider however could not change from bright yellow to pale pink, even after 24 hours!
It was probably successful in catching insects nevertheless. It pounces and grips insects with the crab-like action of its front legs. The petal was less than 1.5cm in length.
Spider web - probably the start of a Nursery Web, after heavy rain,
showing how strong the the single web strands are. Raindrops are caught up
in the strands which are stronger than nylon thread.
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