By Margo Hearne--Tides are governed by the moon on a 24 hour 50 minute cycle. It's called a 'lunar day' and it's the time it takes for a given point on the earth to rotate back to the same position relative to the moon. If tides were governed by the sun they would repeat themselves every 24 hours and high and low waters would occur at the same time each day. The difference in depth between high and low water is called the tidal range and the number of high and lows in a 24-hour period is called the tidal cycle. (www.dfo-mpo.gc.ca/Library).Interestingly, there are two super-moons this month. One on Jan. 1 and one coming up on Friday Jan. 30 as we head for the full snow moon in February. They are extra close to the earth and give us the biggest tides of the year. On Jan. 1 the tide was 24.3 and on Friday the tide will again be 24.3. They're called perigean (closest to the earth) spring tides. If the weather stays fair, the big tides are usually OK, but southeasters often coincide with the springs tides and can be trouble. When working in or by the water it's helpful to know what the tides are doing. Hence, complicated tide charts, because the high tides at Masset will be at a slightly different time than the tides at, for instance, Rose Spit or Sandspit. Bird movements are governed by tides, fish flow by the islands depending on the tides, whales seems to know when to catch the tides and fishermen try never to run out of Masset Inlet on a rising tide or they will be standing still, especially this coming Friday morning.