Drawn to Quebec: Have the ladybugs flown away?

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Photo: Illustration © Bethann G. Merkle, 2014

It might be time to revise that childhood rhyme in which we admonish the ladybug to "fly away home." It all depends on which species you have on the tip of your finger when you start reciting the poem. Some of Quebec's most recognizable insects have vanished, possibly due to new species taking over.

Disappearing act

Twenty five years ago, the nine-spotted ladybug was one of the most common lady beetles in the Northeast. It was also one of the most economically important, thanks to beetles' habit of eating aphids. And yet, today, this species (Coccinella novemnotata) and its fellow ladybugs, the two-spotted ladybug (Adalia bipunctata) and the transverse ladybug (Coccinella transversalis) have practically vanished from Quebec and most of the eastern regions of the continent.

In fact, the nine-spot was thought to be extinct until a pair of children in Virginia discovered one in 2006. Their find catalyzed entomologists (insect scientists) to launch a massive effort to find more. The result was the Lost Ladybug Project, based at Cornell University in New York state.

Spotting ladybugs for science

For nearly a decade, the project has collaborated with individuals, teachers and classrooms, and researchers to photograph nearly 30,000 ladybugs in the wild. The main objective is to catalog when, where, and how many ladybugs of various species are seen. Quebecers interested in helping scientists study our local ladybugs can visit www.lostladybug.org for simple instructions on how to photograph and identify native ladybugs, as well as how to submit your photos to the database.
Happily, some of the thought-to-be extinct species have been spotted numerous times. However, these once-common insects remain rare compared to the overall number of sightings.

Lady...what?

The smaller-than-a-paper clip insects we commonly call ladybugs are technically not a bug at all. This is because ‘bug' is actually a scientific term for certain types of insects, and ladybugs don't qualify. Instead, these crimson little critters are beetles belonging to the Coccinellidae - the lyric-sounding family of beetles known for their vivid scarlet, yellow, and orange colouring and striking black (and/or white) spots.

Also known as ladybirds and lady cows, ladybugs are more properly called lady beetles or ladybird beetles. The "lady" in their name supposedly comes from the association pious medieval farmers made between the beetles and their prayers to the Virgin Mary for relief from crop-devouring aphids. Another possible origin for the common name is Mary's scarlet-coloured cloak, which the beetles share. Regardless of religious affiliation, the Latin word coccineus, the root of their scientific name, means ‘scarlet.' Incidentally, we do not have ‘laddie bugs' - although there are distinct male and female lady beetles, all are referred to as ladies.

What's a lady like?

Lady beetles are predominantly carnivorous, and most of the ones we're likely to see in Quebec eat aphids and aphid larvae.

Lady beetles can live from two to three years in their natural environments, and females produce hundreds of eggs at a time. Though lady beetles are generally not harmful to humans, if you spot them inside your house in autumn, it is best to gently return them to the outdoors. Ideally, there are no aphids in your home, so setting the beetle back outside is the best way to ensure it is able to store up enough energy reserves for the winter. Like most of us, local lady beetles spend the winter right here in Quebec.

Nuisance newcomers

These vigorous beetles are typically much-appreciated by farmers. Alas, little distinction was made between the benefits of native lady beetles vs. Asian species throughout the 1900s. Particularly in the 1970s, aphids were devastating crops across North America, and millions of multicolored [sic] Asian lady beetles were imported to help.

Today, despite its scientific name - Harmonia axyridis - relations between our native lady beetles and their Asian cousin are strained. The Asian species is larger, more voracious, and resistant to diseases which it transmits to other species. In a word, they are outcompeting the native beetles.

Indeed, aside from the loss of agricultural lands, the invasion of the multicolored Asian lady beetle is likely the main reason why our once-common lady beetles are now so rare. As if a seemingly dramatic shift towards this species is not sufficient cause for concern, this is also the species capable of spoiling wine grapes. To add insult to injury, unlike our native species, the newcomer does bite humans, can be allergenic, and gives off a particularly unpleasant odour when handled.

Looking for more?

Visit this column's blog at www.drawntoquebec.com for extra sketches from each week's article. This week's post includes lots of resources for how to identify and encourage native lady beetles near your home, along with great books and materials for teaching children about lady beetles.