In the last month we have enjoyed some nice warm sunny weather which has given the many invertebrates, from moths to hoverflies, a chance to emerge and not forgetting the midges! This has been great for the breeding birds as they relentlessly forage for food for their hungry chicks including the newly fledged pied wagtail chicks outside the volunteer accommodation.
Pied wagtail chicks waiting to be fed outside volunteer accommodation – by Gavin Chambers
Given invertebrates are the prey item for so many predators, such as birds and other invertebrates, some have come up with ways of reducing their chance becoming breakfast. The hoverfly volucella bombylans (photo below) is one of the better mimics which looks a lot like bumblebee species, and amazingly has more than one colour form as shown in photo below. Incredibly this species lays its eggs in the nest of bumblebees which makes you wonder if the bumblebees themselves are fooled by the mimicry? However, it is generally thought that mimics look like bumblebees and/or wasps to make them look noxious (i.e. distasteful and likely to have a sting) to put predators off eating them.
Volucella bombylans (hoverfly) at Lake Vyrnwy – by Gavin Chambers
Moths are also good at mimicry to try and avoid predation. In general they use camouflage to blend into their typical habitat such as the buff-tip which looks a lot like a birch twig. Others will use bold flashes of colour to warn off predators with a few species having the larges ‘eyes’ as seen on the peacock butterfly.
Buff-tip – by Gavin Chambers
Despite their size invertebrates can travel very long distances, using weather systems to blow them to a new location. Species such as the painted lady butterfly and humming-bird hawk-moth are well known for their movements from Africa and the Mediterranean. However, this year has seen a mass movement of a tiny moth, plutella xylostella (diamond-back moth), with a wingspan of only 15mm. It is thought that millions have arrived from Continental Europe though we have only had a maximum of 7 in the moth trap.
Plutella xylostella (Diamond-back moth) – Archive photo by Gavin Chambers
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