Halloween Nightmare – for a snail!

It’s All Hallow’s Eve. Gore-spattered ghosts, ghouls, and goblins roam our streets in packs.  Vacant eye-sockets glare at us from dark doorways, and dripping bushes. Blood curdling wails of pain and screams of fear echo through the neighbourhoods.

Putting the frighteners on ourselves is all part of the fun, and the scary stuff is not that nightmarish when we know that once all ‘tributes’ have been collected, a warm home awaits us with hot chocolate and a feast of goodies.

However, from our comfy seats at home, can we give a thought for the lowly snail? If snails could think like we do (they don’t) surely their Halloween Nightmare would be one that would terrify us too – trapped, unable to move, and being eaten alive, head first, Hannibal Lecter style.

And that’s what’s happening below; not in the movies, and not in our imaginations, but for real.

Calosoma and snail

Calosoma ground beetle eating a snail.
Click to enlarge.

With the beetle’s mandibles plunged into the opening of the snail’s shell, the hapless gastropod is being eaten alive, head first. I witnessed the dramatic scene above while gardening this week .

Ground beetles, like the one above, are quite common carnivorous denizens of our gardens. Often unseen because of their nocturnal habits, we frequently disturb them while digging around in our gardens. Far less frequently do we see them with their prey.

However, it’s a good reminder that many of the invertebrates in our gardens are actually doing us favour, although I’m sure the snail wouldn’t see it that way. In this case our friendly beetle is consuming a garden-plant-eating snail. Remember: Don’t squash the insects, and do avoid the pesticides!

The two hard “shields” covering the back of the beetle and protecting the wings underneath are called the elytra. They are nicely striated in the above specimen, and suggest that it’s in the Calosoma genus. As I’m a bird man, and less of a bug man, my identification of the beetle is provisional.

And while I’m on the topic of ground beetles, I thought I would take the opportunity to share a picture of another striking member of this large family of insects. I managed to photograph this beauty last year in my garden after a brief shower left it with a shiny coating of water over its smooth, red elytra. Again, my identification is provisional. I believe this one is a member of the Carabus genus.

Both beetles are in the 25 to 30 mm size range.

Carabus beetle

Carabus ground beetle after a rain shower.
Click to enlarge

Take a close look at the beetle above and you’ll notice it’s missing part of its left front leg, and part of its right antenna.  It’s an eat-and-be-eaten world all around us. So if snails could have Halloween nightmares, then I’m certain that ground beetles would have theirs too. Who can imagine what frightening beasts could attack and dismember ground beetles?

Happy? Halloween.

Alien Invader Arrives in Burnaby – finally!

The Eurasian Collared-Dove’s invasion of North America is a remarkable story. This dainty member of the pigeon and dove family has found human-altered landscapes to be just what it needs to breed rapidly, and spread like an avian tsunami across the continent from east to west. The bird’s arrival here in Burnaby may be one of the final chapters in its conquest of the whole continent, and in particular here on the West Coast. The surprise for me is that it has taken so long to arrive in our fair city.

Eurasian Collared-dove

Eurasian Collared-dove. Since the bird’s introduction to the Bahamas in the 1970’s, its population has exploded and it has spread right across the continent.

For more than six years now, Eurasian Collared-Doves have firmly established themselves in Surrey, Delta, Ladner, Richmond, and up the Fraser Valley. Even though I have been watching out for them, to my knowledge they’ve only just arrived in Burnaby this summer.

Despite my expectation to find the bird here in Burnaby, it was readers of this blog who were the first to notice the alien species in our midst. Back in late July Brian Johnson sent me a couple of pictures of a “mystery” bird he was seeing and hearing in his yard. Bingo! Brian’s distant pictures provided the first evidence I had seen of Collared-Doves in Burnaby. Next up was a phone call a week or so later from Tony Fabian. “Hey George, I’ve got this odd-looking pigeon in my yard. I can’t find it in any of my bird books.”

It took me a couple of weeks more to actually see the birds for myself, and take some pictures that I could publish here. The birds have proved to be skittish, and difficult to get close-up photographs. Finally, my friend Ross McIlroy invited me around to his backyard where the doves were a new arrival at his bird feeder. Although I didn’t manage to get the hoped-for closeup, one of the birds was conveniently perched nearby.

Eurasian Collared-dove

Favouring backyards and back lanes, Eurasian Collared-Doves frequently perch on power lines.

A frequent concern with introduced species, especially highly invasive ones like the Collared-Dove, is their negative impacts on our native species with which they compete for food, territory, and nest sites. So far, Collared-Doves seem to be living harmoniously in North America without significant impacts on our native North American doves and pigeons.

A case in point is its seemingly benign relations with my favourite local member of this family of birds, the Band-tailed Pigeon. It’s good to know this beautiful bird is apparently unaffected by this alien invader. Band-tailed Pigeons breed sparsely in forested areas scattered across our city, but they often show up in large numbers during Fall migration. Their favoured food at this time of year is acorns, which they swallow (whole!) to fuel their migration to points south.

BTPI#1

Band-tailed Pigeons have bright yellow legs, feet and bill, and beautiful, vinaceous body plumage. Click image to expand the image – this is a spectacular bird.

So what’s the difference between these two species – one native and one alien invader? Interestingly both have prominent neck collars and contrastingly patterned tails.

BTPI#2

The dark and light tail bands give the Band-tailed Pigeon its name – nice feeder bird, Ross!

The prominent white collar on the Band-tailed Pigeon above, contrasts with the prominent black collar of the Collared-Dove below.

EUCD#3

Dark collar, pale pastel overall, and dainty appearance characterize the Eurasian Collared-Dove.

So the aliens are now in our midst, and fortunately they are neither to be feared nor shunned. With some careful observation they are easily identified, especially if you are lucky enough to have them coming to a bird feeder in your garden.

Neither species should be confused with the familiar feral pigeon commonly seen along railroad tracks and in parks. That bird is the introduced Rock Pigeon, and that’s a story for another time.

To hear the cooing song of the Eurasian Collared-Dove click here, and then click on the play button.