Friday, 2 February 2018

You'd best practise more..

A high 6.4m spring tide. Most first choice roost sites would be going under under. For a couple of days now the forecast had been for a .2, .3 surge on top, with a fair old wind action thrown in.  The birds were going to be hard pushed over the tide. So I'd promised myself a trip up Tiptree Hill to monitor.

Tiptree has long been known as one of the very best viewpoints for the estuary, featuring in just about every 'Where to watch..' guidebook published over the last fifty years, yet has fallen out of favour with birders. I've not bumped into one up there in the five years I've been going. One local does visit about once a fortnight, but usually at a set time, meaning my tide chases rarely match. Solitude is still possible in the over-crowded south-east. Why don't birders like it? Well, the views are never going to be close! Viewing the spectacle seems to be out of favour nowadays, with most chasing the money shots. And, when I've asked birders, the answer I get is that they either don't like the walk (450 yards up an incline), or don't like to leave their car on the lonely backroad below, admittedly a favourite site for break-ins. Safest parking is in Lower Halstow a whole mile away.

For the purposes of this note I'll stick mainly to the middle distance.  The screengrab below details the main areas mentioned. About a mile to Barksore's roost. Just under a mile and a half to Slaughterhouse Point on Greenborough, a similar distance to Millfordhope.

I use a favourite mapping website at the moment as it has a set of googlemap images that were taken at high tide, around a 5.9 metre height. They show how the old sea walls have given way in places to allow the once enclosed, once farmed island, to revert to salt marsh. The dark green colour is no trick photography; at this tidal height the ground is saturated. On tides over these heights, much goes under to leave a broken framework of sea walls. In the photographs that follow, the seawall of the southeast corner of Greenborough, Slaughterhouse Point (lined in green, above) features.

On a day like today not many pleasure-boaters venture far out in the estuary, and are rarely holed up among the islands. In the summer, north and east of Greenborough are popular areas to hole up. Yet for much of top of today's tide, there was only boat out there. Birders on a rib, sadly, pushing the birds around.

Does it matter?

Well, let's take one goose: the Brent. Often on lower tides loafs closer to countable areas along the shoreline. The islands are regularly shot by wildfowlers. On Higher tides? Into those islands, tentatively, now they have been deserted by the gunners. The lure of saltmarsh feeding. On these, the highest tides? With the ground flooded, any remaining saltmarsh seed floats. New easy access food sources become available, often gathered in lea of any sea walls above water on the islands, or floating above the plant stems rising from the shallow inundation. Of course, this late in the season, the amount of such food available is already depleted, but any surge will give a chance at picking up a little. So many wildfowl will be floating over the islands, trying to feed. Even if not that hungry, the duck and geese will float over the islands themselves, as much less choppy, with less chance of getting disturbance by any river traffic.

Studies have shown disturbance to Brent causes a time-delay of around twenty minutres before normal behaviours are resumed- by that we're talking about the easily observable (feeding), the subtle (the vast majority of the disturbed flock coming off alert mode) and the unobservable to the field worker, stress rates, etc.

So, at the time of the pictures, even though a skipper might argue they were a fair distance, the clue you should pick up on that tells you you're disturbing the birds is their flighting.

The Slaughterhouse Brent made for Millfordhope. No great problems then? Here's the rub. The spooked Brent arrived, spooking the Brent already present. Feeding stopped. Only for fifteen, twenty minutes, but right at the point of today's high tide, when those areas least inundated over a season were wet open food bars for their picking. Denied Slaughterhouse, they doubled up on Millfordhope, putting all the wildfowl over that island on guard as well.

(If you can't see the clicks, zoom in, they're there, over the island.)
Instead of feeding the geese, in the main, floated over what would usually be the centre of the island, safest from any further boats. The only other active boat was the Harbourmaster who, on spotting the rib from Lower Halstow, made a sortie via Shepherd's Creek to give the occupants the once-over (never mind safety concerns, illegal landings can and do happen around the south shore). So, as well as pushing the birds themselves, by their very presence the rib-birders had inadvertently created a second disturbance.

Of course, that's the story of one species; all the other wildfowl spp. present were disturbed similarly, albeit all with subtle differences in behaviour. So too were the waders, but I'll save that for a second post. I will just mention today's birders and their silhouette effect. The temptation for observers on a rib is to remain standing when drifting. And why not? Birders on small fishing boats do the same. But they are often riding higher in the water, with a walkable deck and seating in the centre, so birders tend to step back a bit, or mill. Appear as if not totally focused on the birds. Essentially, not do an impression of poor seawall fieldcraft for long periods as these guys did. You first stand up, birds will alert. You stand up and stare at wildfowl, they will be on guard. And if you're too close, they'll flight.

Best practices.

We birders often believe we hold the higher moral ground. We expect other users, the seaplanes, hovercraft, microlights, drone users, kayakers island visitors to adopt best practices around the estuary to keep disturbance down and help meet the legal international obligations to protect the estuary. Actually, that's polite, many birders would call out for tougher rules in place based on the levels of disturbance evidenced. So why not best practices for birders?

There already exist best methods for breeding species that can be adopted. Sadly, in many recent years, they have been ignored. Two years ago, a collapse in colony numbers in the days following landings to count. Last year, many failed to return.

Best practices for shoreline roosts are already adopted elsewhere in the county. Here, we still lack even basic signage on our reserves. Adopting best practices has never been more needed, and never likely to have a better chance at a time County and Local Councils set up an initiative to reduce disturbance around this area.

If you flush birds 'on' the islands, you're too close. Move away. Don't keep pushing the birds around as these guys did today. Even if you're counting, as these guys were today (of course I had recognised that rib). One thing also clear from up on Tiptree; certain flights moved from the first counted areas to later counted areas, often via circuitous routes (Sharpness to Greenborough via Slayhills a good example today). The argument that the islands cannot be counted well from shore remains one worth exploring; on any day neither their counts, nor mine, will be both accurate and precise. On a high spring, in late winter, my count doesn't stop the birds from a rare feeding opportunity.

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