Since spiders are hunters, there is a knock-on effect from the success of their
prey – insects thrive in warm, dry weather – but they also show an aversion to damp.
It is Britain’s wet oceanic temperate climate, rather than deep winter cold, that limits so much of our wildlife. Spiders are very much thermophiles, as are bees and wasps which also favour warmer places and do better in warmer years.
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With damp comes coolness, an inability to forage, danger from moulds and fungal diseases, and the threat of drowning.
Spiders breathe using a multiple flap system of gill-like ‘book lungs’ which, if they become wetted, are more liable to suffocation than the more flexible arrangement of internal gas-exchange tubes (trachea) used by insects.
With their tough, waterproof chitin cuticles, insects are also better able to suffer moisture, even sometimes prolonged inundation.
It’s no coincidence that our ponds, streams, lakes and rivers are alive with insects but there is only one truly aquatic spider – the diving bell spider Argyroneta aquatica.