Preserving the Pisauridae

Preserving the what?

Pisauridae is the family name for the various species of water spider which, while not exactly on the endangered list as yet, are nevertheless heading down the road towards rarity, as urban sprawl and excessive rural land clearing threaten the ponds and streams which are their natural habitat.

And that is a real shame because these spiders are as beautiful as they are unique.  The only truly aquatic spiders, they are completely harmless to humans (although adults have large fangs and  can give a painful bite if handled) these graceful arachnids live their entire lives around water.  In Australia, water spiders inhabit the coastal areas right around the country.

Excellent swimmers, water spiders can skim at incredible speed across the water surface when startled, but will also happily dive beneath the water and swim just as swiftly to a safer spot if threatened by a predator.  And did I say these guys are fast? Good, because they so are!

Water spiders are nocturnal, coming out in the evening to take up a position at the water’s edge where they anchor themselves via their back legs to the bank, an overhanging rock or piece of log or foliage, while spreading their other legs out across the water surface. And there they wait until dinner arrives. Their main diet is insects, but they also like the occasional small fish or small frog and the odd tadpole. They will eat a lot of mozzies (mosquitoes) which is ideal and on the whole, will live harmoniously with the other denizens of the pond or stream.

Ranging in colour from black through dark grey, brown, occasionally speckled and golden yellow, most have a distinctive while stripe down each side of their body. Males grow up to 10mm long and females to 30mm. Their leg span can be up to 180mm (18cm) so if you have a pond in your garden, your paddock or a gentle creek meandering through your property and you decide to nick out with a torch to see if you have any resident water spiders, you’ll be unlikely to  miss ’em, and those body stripes are borderline reflective in torchlight. One of the larger species in Australia is Megadolomedes australianus, also known as the Giant Fishing Spider. You definitely won’t miss one of those if it has downed stakes in your pond. And lucky you if it has!

The thing is, these spiders must have a body of water to survive. They can make do with wet, mossy ground but given the choice, they will opt for water every time. Which is where you can come in. Do you have a spot where you could put in a pond? It doesn’t need to be huge and plant nurseries often carry a range of ready-to-put-in ponds that would be ideal. Place some rocks around it, plant some leafy foliage and then leave it to become it’s own mini ecosystem. The frogs will come, the insects will come and if you are really lucky, so will one of the beautiful water spiders. Keep the water level up and the water free from becoming stagnant and the local aquatic life will thank you. Almost all gardens will benefit from a water feature anyway, and they can be made really attractive, but mainly you will have created a safe haven, as well as a point of interest when you suss out what has moved in.

Certainly, you will want to ensure your pond child safe, if you have little ones, but there are various ways you can do this which will still allow everyone to enjoy the pond, but will prevent the littlies from falling in.

Perhaps this could be your next home project. You could probably do this over a weekend or two and the whole family could be involved in the planning and the actual doing, and have something really attractive to show for it at the end.

And while we all still have a degree of lockdown time on our hands…

Go for it.




Leave a Reply

Your email address will not be published. Required fields are marked *