It’s dark outside and you, dear reader, are settled inside for the
night. In the corner of your eye you notice a movement. Do you see it? There,
lurking by the windows. It’s only small but as you turn your head you realise
that there are many of them. The mass appears almost liquid-like as the
creatures crawl up and over each other. As you move closer to inspect the
source of your curiosity, you feel something hard hit your cheek. Suddenly unconfident,
you reach for the light switch, the main light comes on and everything stops!
The tight mass that previously was moving can now be clearly seen as a mound of
red, orange and black. What are they? They my curious friend are ladybirds,
Harlequin ladybirds (Harmonia
axyridis), and generally not the source of nightmares.
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| Four of the hundred or more Harlequin ladybird colour pattern varieties can be seen at the bottom of our FSC guide. |
Alternatively known as the Halloween Ladybug in America - as they
often appear in people’s homes around Jack-o’-lantern carving time - homes all
around the UK, including FSC Preston Montford, are seeing an influx of these
insects colonising the cosy corners by the windows and walls. This season’s abundance
is likely induced by the continuous high temperatures over the summer. First
arriving on our shores in September 2004, the Harlequin ladybird is native to central
and eastern Asia (Kuznetsov, 1997). They were used as a biological control agent
for aphids in North America due to their predatory efficiency and ability to
colonise a range of habitats (Majerus, M. et al., 2006).
Unlike our native ladybirds that generally hibernate in trees or
leaf litter (BBC News, 2018), the Harlequin ladybird prefers to over-winter in
our warm buildings. So, does this resident pose a problem to us? For the most
part, no, these ladybirds are generally harmless and can be left where they are
(BBC News, 2018). If aggravated, the Harlequin ladybirds exude a defensive
chemical from their joints which has an unpleasant smell and can stain soft furnishings
(Majerus, M. et al., 2006). Not a trick you want played on you this Halloween! One
of this ladybird’s favourite treats is the sap from fruits such as pears and
apples, which help to build up the Harlequin’s energy reserves but could leave
your fruit blemished (Majerus, M. et al., 2006) – maybe cover up your fruit
bowl if you notice them taking an interest.
So what can you do until they awake from their slumber and head
back into the garden? Well, you can upload your sightings onto iRecord so
scientists can monitor the distribution of this invasive species. More information
can be found on monitoring UK ladybirds at: http://www.ladybird-survey.org/default.aspx.
Alternatively, you can make up your own ghoulish story about the ladybird lodger
that appeared unannounced. We’re doing both with ours…Happy Halloween!
Sources
BBC News (2018) Harlequin
ladybirds swarm into homes after hot summer. Available at: https://www.bbc.co.uk/news/uk-45766496
[Accessed on: 29th October 2018]
Majerus, M. , Strawson, V. and Roy, H. (2006), The potential
impacts of the arrival of the harlequin ladybird, Harmonia axyridis (Pallas)
(Coleoptera: Coccinellidae), in Britain. Ecological Entomology, 31: 207-215.
Kuznetsov, V.N. (1997) Ladybeetles of Russian Far East. Memoir
Seis Editor, CSE, Gainesville, Florida.
