Horse flies

The principle aim in doing this job is to create the best possible condition so that each habitat - for example marsh, woodland and heath - can support the greatest variety of wildlife.

This is often quite an uphill battle and can be a rather lengthy and complicated process.

I had always felt uplifted when encountering new species growing or living on the reserves.

However, recently I encountered another new species on one of the wetlands that I am still not sure whether I should celebrate discovering.

Maybe once the swelling has gone down and the itching from the rather nasty bite it gave me subsides, I will think more kindly thoughts towards this creature.

Horse flies when you catch one biting are hard to befriend, but they do have a certain aesthetic beauty and if you can detach the fact that you are often their prey they are wonderfully designed predators.

Unfortunately, the best look I've had of these creatures is when I have swatted one as it was in the process of biting me but a closer examination reveals its beauty.

They have amazing multi-coloured metallic eyes, which shimmer with golds and reds. Some species also have bold yellow patterns on their backs and lovely mottled wings.

It is usually when taking the time to admire their beauty that their fiendish adaptation to their blood- thirsty purpose comes to your attention.

Beneath their amazing eyes is a short broad triangular mouthpiece, which is perfectly designed for cutting into flesh.

Then you notice that despite having given the fly you are holding quite a hefty swat it has only been stunned and soon starts to recover.

This is due to their extremely strong exoskeletons and shock absorber- like limbs which absorb all but the most powerful strikes from above.

Horse flies also show great courage and determination once they have found a prospective victim.

Their flight is silent so as not to alert you, but its purposeful and smooth zig-zagging flight can give its presence away to a trained eye.

They usually target a light coloured area as this would indicate areas of soft under belly on the horse fly's usual target, livestock.

Even if you detect the hunting fly it takes quite a lot to put it off its attack and will often press on an attack even after frenzied swatting attempts.

Horse flies are very infrequently encountered on the reserves and the risk of meeting one is quite low even on the wetlands.

However, if you are worried, some of the wasp repellents on the market seem to me to be quite effective at deterring them.