By Margo Hearne
The sun is out and it’s cool and breezy. It feels like it’s time to get out the cool-weather gear. Things feel a little more relaxed all around. The kids are back at school and many adults have returned from vacation. It’s been a busy summer. The islands are being “discovered” — there seemed to be many more visitors taking the time and spending the money to get here. Some are staying a few days extra to take advantage of the out-of-doors.
We too stayed longer on the beach the other day as we waited for the tide to fall and expose the rich pickings left behind. The tides were smaller and seemed to take ages to leave. When we checked the tide charts it was interesting to note there is a real time difference from one day to the next. For instance, last Tuesday the low was at 8:26 a.m. and on Wednesday it was at 9:51 a.m., about one and a half hours later. Then on Thursday, the low was 10:57 a.m., only an hour and six minutes later. Tides move more slowly during the neaps, or small tides, then both time and tide gallop along as the tides get bigger.
In a recently published book Tides by Jonathan White, the author noted that the combined power of the thousands of tides around the world “is enough to inhibit the spin of the Earth and allow the moon to speed up. Four hundred million years ago, the planet experienced 21-hour days; our 24 hours are the result of the swelling tides dragging the Earth back as it spins. The tides are slowing down our sense of time itself.”
The good old moon used to be closer to Earth 3.5 billion years ago and the tides rose several hundred metres high, leaving huge intertidal zones that stretched for hundreds of kilometres. Now we have perhaps 800 metres or so of the intertidal zone where the sands lie flat.
Birds love the intertidal. This week they hung out lazily on the beaches, preening and poking among the rocks. Nearby, large schools of pink salmon swirled around the river mouth and dead fish lay in the too-shallow water. There has been no serious rain for ages and although pinks don’t travel a long way upriver to spawn, they still need fresh water. It was sad to see them. They had come all this way to create the next generation only to find an almost dry riverbed.
As the tide fell at Tow Hill beach, hundreds of Sanderlings ran along the low beach, looking a little like foam left by breaking wavelets. They ran about busily, feeding on tiny things. They may well have been slurping up the biofilm that other sandpipers feed on, but perhaps not. The waters rush in and out too quickly and sweep things away.
Bird movement is patchy. Where are the juncos? A flock of nine white-fronted geese landed in front of us for a brief moment before leaving, then 19 northern pintail appeared from nowhere to remind us that, although time and tide don’t wait for anyone, birds usually know what’s going on.
