Harlequin killer targets native ladybirds, butterflies and moths

harlequin ladybird
Harlequin ladybirds pose a deadly threat to native insects, including other ladybirds and butterflies

OUR LADYBIRDS are bearing the brunt of humans’ short-sighted interference with nature leading to my family’s first encounter with the invasive harlequin ladybird.

The harlequin, or Harmonia axaridis, is a larger, more voracious type of ladybird that originated in Asia and was introduced to north America in 1988 to eat other insects that were considered pests.

But if you’re a fan of Sci-Fi movies, where humans think they have something under control, until they don’t, then you’ll be able to guess what happened.

Harlequin ladybird encounter

Our harlequin experience took place in Cork city last week – myself and my husband grew up in north Cork and we met in University College Cork so we’re keen that our two Waterford girls also feel a connection.

Anyway, Ava (11), Becca (8) and I were spending the afternoon in the lovely Fitzgerald Park – think leafy trees, sculptures, large ponds, a playground and even a heron – when it all kicked off.

7-spot ladybird
A 7-spot ladybird in our garden this summer

The girls are used to finding 7-spot ladybirds at home. This year, numbers have been incredibly low but previously they’ve spent many summer hours hovering around nettle patches in the garden counting ladybirds. The advantage of being busy is that you’ll never have a manicured garden and so, in your own way, can provide a haven for insects etc!

Both girls know not to pick up ladybirds, to just observe, but Ava felt she had to ‘rescue’  one that she had found in the park’s parched playground.

Harlequin ladybird
Ava’s Harlequin ladybird

I took a photo of the little insect before she placed it safely on a bush, wondering if it was possible that Ava had found a harlequin (see pic on left) and hoping she had not. It looked bigger and with far more spots than we’re used to seeing so the signs weren’t good.

Second harlequin encounter

So, you can imagine my surprise when, on Tuesday evening, Becca showed me an identical ladybird that she had found! The four of us were doing the open-top bus tour from the city to Cobh that stopped briefly at Fota Island. [Cute aside here – when Becs was very small she used to ask us  when we were going to visit ‘Picture Island’ again – take a moment to think about it]

The girls had been having a blast on the bus, ducking their heads to avoid tree branches and falling leaves, when the insect landed on Becca. 

Two years ago, I wrote a newspaper article about the threat harlequins posed to Ireland’s native ladybirds and the launch of an island-wide survey to give researchers an insight into how they were faring but also to track the presence of the harlequin. So, I wanted to find out if we’d come across harlequins during our holiday.

Harlequins Explained

As I’ve already written, harlequins are native to Asia, but introduced to north America as what has been described as a ‘biological control agent’. Just think about rabbits in Australia and you’ll know what happened next.

They are now classed as an invasive species and conservationists are taking the threat they pose to native insects very seriously.

The great problem with harlequins is that they don’t differentiate between eating insects that humans consider to be pests or the larvae of native ladybirds, butterflies and moths. They can also breed more frequently than our ladybirds.

Since 1988 they have spread throughout north America, crossing the Atlantic and reaching Britain by 2004. Their presence was first recorded on the island of Ireland in 2007, when they were found in pack of celery hearts that had arrived from Cambridgeshire to Lisburn. They were found in the wild in Co Down in 2009 and a year later they were reported in Cork and Wicklow.

Our harlequin sightings were confirmed by expert Dr Roy Anderson, who quickly and kindly replied to my email, telling me that since arriving in the Cork area less than a decade ago the insect had become “very common” in the city centre and was also “common now” on Fota Island.

However, Roy also said that even with the harlequins’ growing prevalence in Cork, it “isn’t much reported in Waterford and Wexford”. We live in an area rich in native flora and fauna, so I’m hoping our ladybirds have some chance of avoiding their harlequin cousins.

Since the weekend, I have reported our harlequin sightings to the All Ireland Ladybird Survey – Roy is among the participants, along with Fota Wildlife Park, UCC, National Museums Northern Ireland (CEDAR), the National Museum of Ireland, biology.ie and the Irish Wildlife Trust.

They are working together to correlate information on the distribution of ladybirds, with the aim of creating plans for the conservation of our native species and an understanding of how they are being affected by the harlequin.

Conservationists are looking for the public’s help in their battle to save our ladybirds and by simply contributing to the survey we can do our bit for these much-loved insects, who are a great friend to anyone that grows roses!

If you would like to report sightings of native ladybirds to the survey then start by clicking here to identify the types you come across. If you think you may have spotted a harlequin click here to check the various types that are found in Ireland (they come in a variety of colours and spot patterns). Then just access the 2016 All Ireland Ladybird Survey and your information will help the experts build the picture they need.

I’ve previously blogged about how we, as citizen scientists, can help benefit conservationists’ work by passing on information to nature surveys.

And you might also be interested in reading about my fairly recent encounter with another invasive species  – the American mink!

You can access my blog and to follow me on Facebook and/or Twitter here – all visitors very welcome!

Leave a Reply

Your email address will not be published. Required fields are marked *