THE current hot weather across East Lancashire is giving a much-needed boost to plants and animals.

But experts have warned that a prolonged period of sunny weather could also encourage invasive species, and impact on the natural habitats of native flora and fauna.

The Harlequin ladybird has been on the increase in the south of England since 2007 and could cause damage to plants if they came to the region.

Several plant types, including Japenese knotweed and Himalayan balsam, are also continuing to grow rapidly across the North West, boosted by good weather.

They grow well in disturbed, or nutrient-enriched, conditions, to the detriment of other plant species, after being introduced to this country by accident, or deliberatly in gardens.

The ladybirds, which have colonised the whole of the south over the last few years, are gradually moving up the country, causing damage in new regions because they eat plants other species rely on. They are more competitive, and breed quicker, than British ladybirds.

Lindan Marquis, from Natural England, said: “There is a potential that this could happen, but we will know for sure at the end of the month and if the weather holds up. There is no guarantee that the animals will come north, but it is perfectly possible. These sorts of animals have a huge impact on the habitat of others and we will take action if we need to towards the end of July.”

Japanese knotweed was first introduced to Britain during Victorian times as a decorative plant in gardens, but has since spread and grows wild. In 1981, it was made illegal to spread its seeds.

Himalayan balsam is found mostly on river banks and in damp woodland, but can grow in other damp habitats. Teams of volunteers have recently been digging it out from some parts of East Lancashire.

Alan Wright, from Lancashire Wildlife Trust said: “At the moment there is not a problem with invasive animals in the region, but there could be if the weather holds up.

“The main thing at the moment is that the wildlife we have, such as those at Brockholes Nature Reserve, are doing very well and I hope that continues.”

Mr Wright said species benefiting from the heatwave, following a prolonged cold spring, include lapwings, red shank and brown hares.

Colonisation

  • Harlequin ladybirds are the newest non-native species which look set to make their home in East Lancashire after first colonising the south east six years ago.
  • They are most commonly found on deciduous trees, such as lime, sycamore, and maple, and on low- growing plants like nettles.
  • They are also just as happy living in reedbeds, coniferous woodland, and crop systems.
  • Like all ladybirds, they undergo a complete metamorphosis, starting at the egg stage and moving through the larval, pupal and adult phases.
  • Pre-adult development takes about 14 to 20 days at 25ºC and adults can begin to lay eggs after 5 days.
  • A single female can lay over a thousand eggs.
  • They usually eat aphids, but also enjoy feeding on scale insects, the eggs and larvae of butterflies and moths, small insects, pollen, nectar, and honeydew.