Tuesday, 20 February 2018

Getting that last shot in

In England and Wales, the wildfowling season starts on September 1st, ends January 31st. With an exception, because those dates are for 'inland'. Birders sometimes miss that the season 'below high water' continues until February 20th. The definition for 'below high water' is any area below the high water mark of an ordinary spring tide.

Of course, most estuaries do not have an island complex like the Medway's. With the number of breaches to the seawalls on those islands, much of the 'ground' goes under, so there are plenty of opportunities for wildfowlers to continue shooting until the 20th.

The last weekend of the season is traditionally busy, and always seems to start on the Friday. The 16th saw many of the island shooting hides manned. Very few shots heard in two hours, and the fowlers were away soon after the top of the tide, but the lack of gunfire didn't mean a complete fail; late season wildfowling trips are as much about the tradition of marking the season out. It will be over six months until the next season starts.

How do you define an ordinary spring tide? Essentially, a series of spring tides occur every 14 days when the moon is full or new; the moon and sun are lined up. It isn't as simple as that because distances between the sun and the planets change. The moon is on an elliptical orbit. Some springs are higher. The sun has a tidal effect about a third in strength of that of the moon, and as the earth travels around it on its own ellipse  the effect on tidal height will differ (if we ever did lose the moon, there would still be tides, just 66% or so low, and no springs/neaps). This is why, about every seasonal Spring and Autumn we see tidal perigee springs, three or four in each year (there are 13 lunar months in a year causing further wobbles in calculations). Every eighteen months or so we get a monster high; the proxigyean spring tide. This is on the 'super' super moon, the moon's closest perigee to earth, in the new moon phase (when the moon is between the sun and earth, making for slightly higher springs) and when we are closer to the sun.

So, in reality, February springs will be 'ordinary';  the wildfowlers can shoot over the flooded islands. The perigrees happen March/April. Once out the way, there are then three months before the next high highs. The old Kent bargemen and fishermen used to call these lower springs 'the bird tides'- the safe time for breeding on the islands.

Safe is relative. A few years back, bird tide springs could be 5.7, 5.8 metres. This year, the tide tables are full of 6.0, 6.1 metres. And surges don't really enter into these equations. Throw in some low pressure systems and spring tides in the breeding cycle will be flooding the islands.

Last Friday there was a three centimetre surge; some the wildfowlers were had water lapping around their feet. The roosts were being moved by the tide, the wildfowl being spooked by the shooting. Of course, duck numbers were down, with many having left for the near continent to start staging towards summer breeding grounds (the wildfowlers did a good job in getting closing season dates set where they did).

The shooters got their last shots in. This coming year might see more of the Medway's breeders getting their own last shots in.

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(The waders were still in good number today, but their flights are a story for the next blogpost.)

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