On Being a Blood Donor ...

"Wow! It's such a bad year for mosquitoes, isn't it!"

This was my neighbour Yamaguchi-san, when we were standing in front of our houses yesterday morning. He was out there sweeping the road, as he does a couple of times a day, and I had wandered out to say 'good morning' and just generally pass the time of day.

And I certainly had to agree with him; it has indeed been a very bad year for mosquitoes. Although all the windows in my home are screened, I usually leave my front door proppedopen in order to get a better air flow through the house, and these pests need no further invitation. On a typical summer day as I sit at my desk working, at least once an hour or so I hear the hateful buzz, and have to grab the rolled-up newspaper I keep at hand and do battle with the intruder.

But this year it's not a question of 'once an hour or so', but of every few minutes. They have been coming in waves, and even after flattening three or four of them, it is no more than a few minutes before the next group arrives.

As Yamaguchi-san and I stood chatting about this - and swatting at more of them - we had both been making some kind of comment to the effect that it must be this year's slightly strange weather (wild swings between days of heavy rain, and days of bright sunshine) that was to blame for this, when something suddenly occurred to me. Perhaps it wasn't the weather. Perhaps it was because somebody, somewhere in the immediate neighbourhood, had been careless with their gardening, leaving a container of water exposed.

Ishii-san down the street does indeed have some large jars of water in front of his home, in which he grows some aquatic plants, but he swears that the goldfish he keeps in them take care of any mosquito problems, and I think this is probably true. So Yamaguchi-san and I took it upon ourselves to make a little survey of the area, looking for a possible source of infestation. This is not actually so easy, because you have to be a bit discreet when peeking over people's garden fences, but we had a look around anyway.

We turned up nothing, and came back to stand in front of my house, just at the spot where noodle shop owner Hamanaka-san has his 'unmanned shop' - a little covered shelf unit where he places packages of noodles every morning, along with a little cash box. (He has recently has some problems with theft from this, but that's another story!) This unit stands in his parking lot at the point where his property bounds mine, but it is invisible from my place because it is overgrown by the wisteria that covers the side of my house.

We stood there slapping at mosquitoes, and I suddenly burst out with, "Look, this is insane! There are so many of them. There must be a source very near here!" We poked around a bit and a few seconds later, pulling aside a branch of the wisteria, I found it. On the ground behind the shelf unit, no more than two meters from my office window, was an old Styrofoam tray, of the type you see in a fish market. It was full of water, rotting leaves, and floating debris. As I pulled it out from behind the stand to where we could see it properly, we knew instantly that we had found our problem. There were so many mosquito larvae in there that the surface of the water was dancing with motion.

Yamaguchi-san reached forward to tip it over and spill the contents onto the ground. "Just a minute ...," Dave interrupted. "Let me have a look. This is so interesting! Look at them all - big ones, small ones; perhaps if we watch we'll be able to see one being born! I've never seen that! Let me go grab my camera!"

Yamaguchi-san, slapping at his arm, wasn't having any of it. He wasn't about to let this thing survive for as much as another minute, and - slapping at my own legs - I had to admit he had a point. A moment later it was 'game over' for the larvae, and the container was broken up and headed for our garbage bags.

But such a lost chance for scientific progress! :-)

Story #297, September 4 2011