Thursday 25 June 2009

Amphibians and aliens

The volunteers were working at Blashford today and spent the morning clearing the alien plant Himalayan Balsam from along the Dockens Water. Although the task was not inspiring the chance to walk slowly along a length of the Dockens was very enjoyable, it really is a very attractive Forest stream. Along the way we saw a good number of Common Frogs, no doubt nearer to the stream due to the dry weather we have been having the one below was particularly well marked one.

Himalayan Balsam is not the only alien species to be seen at Blashford, there are lots of plants, especially water plants, originally brought in by the aquatics trade and lost or casually dumped into the wider environment. Aliens are not only plants though, the beast below is the larva of a ladybird recently arrived in Britain. It is the Harlequin Ladybird, originally from E.Asia it has spread around the world with the plant trade and is now one of the commonest species in N.America and rapidly becoming so in Europe.

This species, as well as eating aphids is also supposed to eat other ladybird larva, including those of our native species, so part of the increase is probably being achieved by decreasing the numbers of native species. Alien species actually rarely establish, but if they do they nearly always seem to end up causing problems for native species.

Bird Nest updates:
TERNS - A further count of the tern chicks confirmed 34 chicks as well as three adults still sitting.
LITTLE RINGED PLOVERS - The pair nearest to the Tern hide are showing all the signs of imminent hatching, so perhaps this weekend there will be fluffy little ones, let's hope the rain is not too heavy or prolonged.





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