Exploring the wonders of nature
The County Times has teamed up with the Sussex Wildlife Trust to bring you monthly questions and answers about all things nature.
Charlotte Owen, WildCall officer at Sussex Wildlife Trust, is on-hand to answer your wildlife and conservation queries. As well as answering a variety of wildlife queries, Charlotte is always eager to receive your wildlife sightings in Sussex.
WildCall provides fact sheets ranging from how to make bird cake to beach-combing and can offer advice on environmental and planning issues as well as the best ways to help wildlife such as frogs, birds, bats and bees flourish in your garden.
To talk to Charlotte, call 01273 494777 between 9.30am and 1pm on weekdays, email wildcall@sussexwt.org.uk, write to her at WildCall, Sussex Wildlife Trust, Woods Mill, Henfield, BN5 9SD or visit www.sussexwildlifetrust.org. uk/wildcall
This unusual spider, left, is living in my flowerbed, it looks exotic – what is it?
It’s a flower crab spider, and the amazing thing about this species is the females can change colour to match the flower they’re in. They are frequently white, with two red spots, or lines, on the abdomen – but they often sit on yellow flowers, in which case they gradually turn yellow over several days. They can also turn green but any change is a slow transformation.
These spiders don’t weave webs but lie in wait to ambush their unsuspecting prey, and it’s a very effective strategy – they are almost invisible until you know they’re there. The powerful front legs are much longer than the others (contributing to a crab-like appearance) and the spider pounces with incredible speed to grab its prey in a deadly embrace before injecting a dose of fast-acting venom to finish them off.
This allows them to tackle targets several times larger than they are, and bees, wasps, hoverflies, butterflies and other pollinating insects are all on the menu.
Candragonfliesflybackwards?
Yes – and upside down! Dragonflies can fly further, higher and faster than any other insect, and their wings are a marvel of natural engineering. Each one can be operated independently and this provides such exquisite control that a dragonfly can dart off in any direction – even in reverse – and make rapid alterations to its flight path as it chases down its prey, or avoids becoming lunch itself.
High-speed cameras have revealed that dragonflies angle their bodies upwards to fly backwards, so that they are positioned vertically rather than horizontally. Rotating their body in this
way effectively changes the direction of the force exerted by their wingbeats, propelling the dragonfly backwards.
It may look ungainly but it’s surprisingly aerodynamic and efficient, allowing dragonflies to fly backwards for quite some time, and with just as much precision as forward flight. Being able to take off at this angle also allows for a quick getaway when perched in an upright position, darting away from danger.
And that’s not all – dragonflies also have an impressive self-righting mechanism to survive being knocked off balance and will perform a backflip to recover from being unexpectedly upside-down.
They can even do this while unconscious and it’s all thanks to the ‘passive stability’ provided by the shape and stiffness of their wings. This natural response is similar to the way that planes are designed to glide if their engines should fail, and the biomechanics of dragonfly flight will no doubt provide invaluable insight for the design of future technology.
I found these, left, washed up on the beach, can you tell me what they are?
These mystery objects are often mistaken for a beached octopus. They do look a lot like tentacles but they are in fact squid egg capsules, and each finger-like projection can contain some 200 eggs.
Squids deposit these capsules on the sea bed, usually attached to sea weed or some other feature, and each mass is communal – meaning several females would have laid their eggs in one place.
Squid don’t tend their eggs so they are vulnerable to predation and it’s a case of strength in numbers, with each female laying hundreds of eggs in the hope that some will survive.
The eggs will sometimes be detached in rough or stormy weather and will wash inshore, where they can be discovered on the strandline. They usually dry up quite quickly, meaning most are no longer viable, but you could return them to water just in case there are any survivors.
Where do froglets go when they leave the pond?
Tadpoles normally complete their metamorphosis in June, changing into a miniature frog that’s only a centimetre long.
These froglets are extremely vulnerable to predators, from herons and crows to ducks, cats, rats, weasels and grass snakes. They’re also at risk of drying out in the sun or being accidentally squashed, so it’s important to have lots of long lush vegetation around your pond to create plenty of cover and shade. This will help them on their way and also help connect your pond to other areas of the garden.
Froglets need to survive for two years on land before they are fully mature and ready to spawn. This time is spent sheltering in undergrowth, under rocks, in compost heaps and around the roots of trees, where they feed on small beetles, worms, spiders and other invertebrates.
Only a small number of froglets will survive to adulthood, and while this is entirely natural (and the reason frogs lay so many eggs in the first place) you can improve the odds by creating lots of frogfriendly habitats for them.