How often, as you walk across it, have you cast a glance over the side of a bridge just on the off chance of there being something there, but have you ever really stood and watched. Well, yesterday, walking across the bridge at the base of the boardwalk, heading toward north hide, we stopped to admire the crystal clear water when we noticed some movement.
There below us, only four or five feet away, just visible, wriggling through the mud at the bottom of the ditch, was an eel. Only about a foot long, and not much thicker than a finger, it was searching, slowly, across the bottom, looking for a tasty morsel or two, sticking its snout under anything that looked interesting. We were watching it through binoculars when there was a flash of red and there, hovering over the eel's head, was a male stickleback, its bright red belly and greenish eye in stark contrast to the dull black of the eel.
Although only a fraction of the size of the eel, so it could easily have ended up as lunch, the stickleback was relentless, diving down again and again to dart at the eel’s head, trying, and eventually succeeding, in making the eel change direction and head off down stream, before disappearing itself, as fast as it had appeared, leaving us to wonder what the fuss was all about.
Well, male sticklebacks not only set up territories but they also build nests and do all the looking after of the eggs once the female has laid them, so the fact the tiny little fish, no bigger than your little finger, was giving the eel such a hard time probably meant that, somewhere nearby, there was a nest full of tiny eggs on their way to becoming the next generation of sticklebacks.
So, next time you are walking across one of our bridges, take a minute or two to stand, look down and watch. You might not be lucky enough to see the little battle we had witnessed, but you might still see caddis fly larvae, cloaked in their cases of stones and sticks, ambling across the mud, or diving beetles bobbing along in mid water looking for food or perhaps even water boatman rowing sedately along – whatever you see, there is as much going on under the water as there is in the world above it, it’s just on a smaller scale.