Leeches, future-blind, and dogs' noses
Updated: Jun 12
We, along the northeast coast of Australia, are enduring the longest, wettest rainfall period since records began. Since the beginning of this year, we’ve had 1.3 metres of rain pour onto us (the yearly average is .8 metres). The rain hasn’t confined itself to a deluge and then gone away to give us some respite but deluged and drizzled then spat then drizzled before drawing itself up for another deluge. I live on a hill but it feels like I live in a swamp. Of course, leeches are loving it. I have become VERY personal with them. A walk into my paddocks attaches at least three leeches on me and ten on the dogs.
Leeches creep a lot of people out but I think they are fascinating (though I DO NOT like the itch they leave behind when they finish feeding). There are about 500 species of leeches worldwide and they live everywhere except in really arid areas. The species I’ve come to know is Chtonobdella limbate (bush leech). Like other leeches, during dry spells, these beauties with the lovely golden stripe down their sides, burrow into the soil and can even dry out and become rigid. Put a drop of water on them, however, and after about ten minutes or so they’re ready to get up and go! They are hermaphrodites – have both sexual organs. When they mate, two leeches wrap themselves around each other and give each other sperm gifts into their respective ovaries. Neat!
The leech in the image above is standing straight up, not because it was attending to my stern talking to for having attempted to attach itself to my ankle, but because it was trying to scent where its meal had suddenly moved to.
Yesterday, as I walked along the beach, I saw the clouds come rolling in – my dog, Zoe, a grey spot against the grey sky. More rain – expected because we are in a la niña period. The weather is also "meant to be cooler but the expected cool hasn't happened. Australia has warmed, on average, by 1.4ºC since 1910 with the last 19 years among the hottest.
I’m thinking this year’s Leeches are the least of our worries. Weather patterns around the world are causing havoc. Desperate people are leaving their drought-riven traditional lands, fleeing from hunger and the turmoil that inevitably comes when people scramble for ever-dwindling resources. The movement of people is destabilising developing and developed countries alike. Decision-makers (usually with dry homes, air conditioning and good food) point fingers at the desperate and blame them for environmental and social destruction rather than recognising and acting decisively on the root cause of the problems.
With these dark thoughts in mind, I sat to watch a program on TV in which community leaders discussed a range of topics concerning regional and rural Australia, including paucity of health care options, the future of coal mining and the impact of climate change. It was a deep discussion with lots of statistics bandied about.
The final question asked by the moderator was something like: ‘by 2050, what do you imagine for your area?’
To my bewilderment, each person’s response was something along the lines of “we’ll have solved our current issues”. Not one person even attempted to paint a scenario of a future in which rising sea levels and storm surges will mean drastic changes to the seaport they currently rely on for imports and exports, or that their own inland towns will need to significantly restructure to deal with increasing severity of flood, drought and weather events. And not one person noted that governments around the world are already struggling with trillion-dollar debts to deal with the natural disasters of the past decade, let alone be able to continue to fund the disasters of the next decade or fund improved-business-as-usual social services.
We humans are truly weird – or blind or something. As I said, my partner thinks I’m pessimistic. Maybe I am. I hope so. But history tells me that we humans more often than not turn a blind eye to oncoming disaster and cling to “how we’ve always done things” and think we can get away with just tinkering at the margins.
Recently my sister encouraged me to watch the movie “Don’t Look Up!”. It was a very painful watch because the scenario is too close to reality.
Enough already of such dark thoughts! Here are some fun facts for your next dinner party
A dog’s sense of smell is so sensitive that a dog can detect substances at concentrations of a single drop of liquid in 20 Olympic size swimming pools (of course you need to convert this to 'air' stats). The dog's outbreath passes through slits on the nose sides and that air-eddy helps to usher in more odours into the nose. When a dog inhales, a fold of tissue just inside the nostril separates odours from the air that's drawn in for breathing. By wriggling their noses, dogs can locate the source (direction) of the smell. In addition, dogs have an odour pheromone detection organ that tells them about behavioural and/or physiological changes. Such molecules are larger than other 'scents' so the dog likes to get close and personal to pick up these scents; they even curl back their lips or lick the air to encourage greater contact with these ‘delectable and informative’ signals about the world around them.