Friday, June 10, 2011

Looking for shiny things

I found a copy of Jewels; a Secret History by Victoria Finlay in a used book shop earlier this week and couldn't resist starting reading it right away (I'm about half-way through now and am enjoying it). My own efforts to find shiny stones have been confined to two afternoons many years apart. Once, as a teenager, I collected amethyst from a hillside near Thunder Bay, Ontario – the purple laced rock provided a unique back drop for my aquarium that competed with my fish for prettiness. Many years later, I went looking for opals in Northern B.C. In between, I made one gold panning attempt where I did find gold but, I was in a gold rush themed park (I think it was a set up for tourists like me).

On the mid-summer day I went opal hunting a hot sun dominated the sky. I set out with my mom and friend, Tracy, on a well worn path through the woods. Opals were said to be common at the end – an old river bed in the forest. Although it was a beautiful summer day, as far as we could tell, our group was the only one in the area. Hiking through the forest was nice – the dirt path wasn't too steep and the trees filtered the sunlight keeping the mid-day heat at bay. I don't quite remember, but, I think we reached the end of the path about an hour after starting.

Instead of a the rocky river bed we expected, a deep gravel-lined ravine extended as far as we could see in both directions before forest swallowed it up. It was a long way to the bottom where shrubs and trees hid whatever was down there. A rocky creek could have been beneath the foliage but, there was no safe way to get down to it. The ravine walls sloped with an optimum steepness where the golf to football sized rocks stayed put until one tried to step on them. A single footfall would start a gravel avalanche that threatened to take a person down the slope with it.

We clambered onto the slope careful to keep our footing while stones ricocheted down the slope, their sound echoing in the ravine. The rocks were all a uniform gray, but, on closer inspection some had milky white globules embedded in them. These smooth globules ranged in size from a gain of rice to a marble and every one was a oval in shape. Were these opals? If so, where was the fractionated interplay of colours radiating from within? In the end, we determined they were low quality opals – no doubt if this area had gem quality opals we wouldn't have been the only ones there.

Each of us slipped a few chunks of opal embedded rocks into our packs, got off the perilous slope and started the trek back to the car. Even though I'm fascinated by opals, the rocks I brought back that day have long ago vanished.

Wednesday, June 8, 2011

sunrise or sunset?



In the first rays of morning light the world feels so fresh and new – I love how the lighting makes everything look. I don't even mind getting up early to enjoy the sunrise – provided I went to bed early the night before. What about when the sun never really sets? I'm thinking of the arctic in summer time (only because I live closer to the northern pole than the southern one). A few years ago, I was on an icebreaker in the Beaufort Sea for a few weeks in July. Since I was taking sediment samples based on a predefined sampling regime, I ended up taking my samples at all times of the day and night – due to factors beyond our control the trip turned into a bit of a sleep deprivation exercise. One station happened at 2 am. As I stood on deck waiting for us to start, the sun was as low in the horizon as it would go and my internal clock couldn't decide if it was sunset or sunrise, so I took a picture.

Tuesday, June 7, 2011

Fireflies

Few insects vie in popular fame with the glow-worm, that curious little animal which, to celebrate the little joys of life, kindles a beacon at its tail-end. Who does not know it, at least by name? Who has not seen it roam amid the grass, like a spark fallen from the moon at its full?

- from The Insect World of J. Henri Fabre, an anthology of Jean-Henri Fabre's works translated from French by Alexander Teixeira de Mattos.

Glow-worms, also called fireflies or lightening bugs (I prefer to call them fireflies), don't live where I do, so I've never seen one. My only encounters have been in fictional accounts, but I can understand how they capture people's imagination – I'd be captivated if glowing beetles 'like a spark fallen from the moon at its full' were flying around my backyard. I suspect I'd watch them for hours, and back when I was a kid, I would have loved to catch them. According to the Smithsonian Institution's Animal; the Definitive Visual Guide to the World's Wildlife, 2000 species of fireflies exist world-wide, ranging in size from 0.5 to 3 cm. And it's no surprise that they're typically nocturnal; what would be the point of glowing if no one could see?

Their light serves different purposes through a firefly's life. As larvae, they flash to warn predators of the larvae's toxicity. As adults, each species emits their own unique set of flashes to attract mates. Males typically can fly around to find their mate, while the flightless females stay in one place and flash. A female firefly's flashing can be the downfall of a male, since some females mimic other firefly species' flashes to earn themselves a quick meal.

A firefly's light falls into the 510 – 670 nm range, corresponding to yellow, green or pale-red and contains no infrared or ultraviolet wavelengths. They produce their light purely through a chemical reaction that triggers a light-emitting pigment to flash within specialized cells in the firefly's abdomen.

Firefly populations are decreasing. Loss of habitat makes life harder for fireflies, and light pollution may be interfering with their signals. In fact, light pollution causes all sorts of havoc for critters. For fireflies finding a mate becomes more difficult, because how can they home in on a series of flashes from a potential mate while lights are flashing all around them? For other animals excess light confuses their sense of navigation, like puffins in Iceland disorientated by city lights. Children rescue the puffins and release them – which strikes me as a bit odd since puffin is considered a delicacy there. Light pollution is such an issue (probably more because it make the stars hard to see than what it does to critters) that there is an 'International Dark-Sky Association' and places designated 'dark-sky preserves'. I wonder what all the excess artificial light is doing to us?

Lots more info about fireflies can be found here.