Asian Lady Beetle - An Invasion!

Harmonia axyridis
There are around 18 species of ladybird beetles in Ontario, all of which feed on aphids and mealy bugs. However, Harmonia axyridis was considered very effective in eradicating the pest problems associated with crops such as soya. Hence it was introduced into USA and thus entered Canada. Here is an account entailing general information and observations on this beetle. 
Asian Lady Beetle showing the "W" mark on it's pronotum
Asian Lady Beetle is a beautiful ladybird native to eastern Asia. It is easily identified by the “M” or “W” mark – whichever way you see it, on the pronotum (just behind the head). It lives for one to three years, depending on the availability of food and surviving winter several times. When disturbed – or handled – it produces an odor to deter predators, the smell is however insignificant and can be easily washed away. They are gentle and do not bite to humans, but some people are allergic to this beetle.

It was first introduced in USA in the year 1916 to control the pest population of aphids, and after consecutive efforts, it became acclimatized to the area. Thence it ever spread farther, and reached Canada. It is now abundant than the native Ladybird beetles seen around. In Europe as well, the species spread quickly and almost replaced native ladybirds of Britain.
Photographed at south shore of Lake Huron during Summer
This is one of the rather skeptical cases of introducing an exotic species to control the pest population in a certain country. There are failed instance which includes introduction of Cane Toad in Australia, to control the beetle grubs that damaged sugarcane. However, the toad developed taste for the native beetles, and soon became an invasive species. This resulted in a decline in the native insect biodiversity along with receding reptile population due to competition for food.

There are several successful cases of biological control of pest population by exotic species. One of the cases is, in which the cottony cushion scale insect – a pest on citrus trees, was the reason for major loss of the Californian citrus industry. A vedalia beetle and a parasitoid fly were then introduced from Australia to control the pest population. After a few years, the pest was completely controlled by these exotic predators. And the availability of food, in this case, the scale insect, determined the population density of the exotic predator, thus controlling its invasiveness.
Aphids are hemiptera bugs, feeding on plant sap.
They reproduce extremely rapidly and thus expand and
exploit the food sources available, including crops. Photographed in India.
However, not all such cases are like these. In case of Harmonia axyridis, the beetle was successful in eliminating aphids – a farmer and a gardener’s nightmare. So long as the beetle consumed the aphids, all was okay. But it spread rapidly all over the place, and replaced the native populations of ladybirds – through competition for food. This resulted in a loss of native biodiversity, and that is not good! Also, it is known to damage crops such as grapes.
“Adults feed on grapes in the late fall for sugars to survive during hibernation. However, they get harvested along with the grapes. When crushed with the grapes they impart a musty odor to juice or wine. The odor is because of a compound called methoxypyrazine, which is a stable compound and resistant to heat, fermentation and filtering. ” Timothy E. Martinson et al, The Buzz on Asian Lady Beetles
Albeit these facts, this beetle is still considered a blessing by a farmer – thanks to its gregarious appetite for aphids.
Different morphs
All Ladybird beetles hibernate during winter season. And so, the best time to see them – in their thousands – is during autumn. This is the time when, all of a sudden, they come and land on trees and buildings. They make it into your homes, and are a menace. But they don’t mean to. They are actually seeking shelter from the coming of cold. Therefore, they seek the corners and warm places so as to survive the winter.
“Houses – particularly light colored ones – look like rock faced cliffs to lady beetles in the fall. This has been a minor problem in Central NY since the mid 90s.” Timothy E. Martinson et al, The Buzz on Asian Lady Beetles
Five different morphs as seen during the invasion
Now, you may come across a myriad of colors from orange to red and melanistic forms, and patterns (such as no spots, less spots, dark spots, so on) on these lady beetles marked with an "M" on the pronotum, and thus around fifteen morphs - or more, exist today, out of which, I recorded only five in London ON. These morphs are a result of genetic variation.

In nature the lady beetles shelter in tree crevices, under rocks and in leaf litter. But unfortunately, they land up on big structures like high rise buildings – mistaking them to be trees, and seek shelter in apartments. But worry not, it’s a pleasurable company!
Two sleepy beetles at my home
According to my observations, many of these beetles that made into my house died after two weeks. And the ones that were all over the place outside, vanished. I think the death was because of being active throughout the time – thanks to the constant warmth provided by my heater but, no food source. The rest of those who vanished must have sought a protective shelter and slept calmly.

So, after a long winter sleep, the ladybirds rise up and go on a search for mates. This happens during spring time. That’s the time when they congregate again and invade homes – actually, to seek shelter for mating. Thus be the life of these beautiful, yet invasive Ladybirds – Harmonia axyridis.
Thank you for reading!

References:

1. Timothy E Martinson, The Buzz on Asian Lady Beetles, Finger Lakes Vineyard Notes #8, August 12, 2002
http://www.grapesandwine.cals.cornell.edu/extension/edocs/Asian%20Lady%20Beetles%201.pdf
2. Kevin W Ker, Questions and Answers about H. axyridis (Pallas), April Harmonia axyridis Seminar, 2002
http://www.brocku.ca/ccovi/news/Q&A.html

3. Kevin W Ker, Multicolored Asian Lady Beetle – New Insect or just Overlooked in Ontario
http://www.brocku.ca/ccovi/news/Asian_Lady_Beetle_-Harmonia_axy.pdf

4. Catherine R Weeden et al, Biological Control: A Guide to Natural Enemies in North America
http://www.nysaes.cornell.edu/ent/biocontrol/info/biocont.html

5. Caltagirone, L. E., Doutt, R. L. The History of the Vedalia Beetle Importation to California and its Impact on the Development of Biological Control
http://arjournals.annualreviews.org/doi/pdf/10.1146/annurev.en.34.010189.000245

Other websites:
http://en.wikipedia.org/wiki/Harmonia_axyridis
http://en.wikipedia.org/wiki/Biological_pest_control

Eastern Gray Squirrel

Sciurus carolinensis

A common mammal of the neighborhood in Canada, it is seen scurrying on parapets and on top of houses, on pine trees and maples. I spent a pleasant time photographing and video-shooting these squirrels.

Here is one of her stance where she curiously and slyly gave me a glance. It is a squirrel native to Eastern and Midwestern USA and southerly Canada. It was introduced in UK and has largely displaced the native Red Squirrel (S. vulgaris). The Gray Squirrel shares its distribution with Fox Squirrel, which is often confused to be a Gray Squirrel. - Wikipedia

From my observations, I found these squirrels fairly common in Mississauga – a suburb of Toronto, and came across several but rather uncommon melanistic forms. The melanistic forms were more conspicuous compared to the common, ordinary squirrels. I also found them to be timid as compared to the latter.

On a contrary, in London ON, I saw a healthy population of the melanistic Eastern Gray Squirrels, about three individuals per one ordinary squirrel. I cannot ascertain why such a difference, but surprisingly, the melanistic squirrels here are not as shy as in Mississauga, and will be often seen sniffing right beside the path. I have seen only two ordinary coated squirrels here.

The melanistic form, which is almost entirely black, is predominant in certain populations and in certain geographic areas, such as in large parts of southeastern Canada. - Wikipedia
It is a typical pose of a squirrel that defines its binomial name. According to Wikipedia, “The genus, Sciurus, is derived from two Greek words, skia, meaning shadow, and oura, meaning tail. This name alludes to the squirrel sitting in the shadow of its tail.

Given HERE is the video that show’s one of the Squirrel behaviors. The Squirrel sat all cuddled up in the pose in the above picture.

After sensing my presence, this Squirrel started making squeaking and chucking sounds. It started wagging its tail and seemed to tell me “I have seen you!” It is a warning signal that Squirrels all over the world use, in territorial disputes, or in presence of a predator such as a raptor or a snake. This squirrel did not start displaying warning signs until I was pretty close to her (at about 15 feet). I presumed a low profile, laying flat on the ground and making no sudden movements. After a while I stood to my feet and the squirrel – in a fraction of a second – vanished in the trees. This is because she probably thought my stance to be threatening and big. It is obvious and easy to observe this behavior – whether you are in the field or, just gardening in your backyard!

All these squirrels observed were not tamed in anyway and I did not see people feeding them, which is a good thing. They do however visit backyards and eat up the pears and apples! These squirrels are the wild-neighbors who now share their natural habitat with a human habitat. Rest of the wild-neighbor list includes Raccoons, Skunks and Rabbits, and in areas close to woods – White Tailed Deer.

I am glad to have sighted these until now, but never had an opportunity to photograph them. The squirrels, on the other hand, are always present and give you a nice company if you’re alone! I find it amusing to see them chuckle and play around trees and lawns as I walk huddled in a hoodie to the lectureroom.

For more on Eastern Gray Squirrel - HERE (Wikipedia)

For more on Fox Squirrel - HERE (Wikipedia)

And another very interesting documentation on Eastern Gray Squirrel -HERE (Hiker's Notebook)

This is my first post away from India. I squeezed out time to do some natural observations around my base in Canada, and this is the creature that struck me first. Keep watching for more!