Flighting up times

The last couple of session out have seen me mainly musing on disturbance- specifically, fireworks disturbance.

The tide on New Year's Eve had been covering just approaching midnight, which could have meant a fair number of birds close to shore. The traditional British approach of letting off fireworks from any time up to six hours before the stroke of midnight had already put paid to that. A check the following night (with fireworks still being let off around Gillingham), notched up fewer than expected territorial waders close in, and no sign of any moving flocks. Daytime checks along the urban stretches showed the species that follow the tide in, weren't. Just a few hundred Dunlin. It takes time for these birds to feel the area to be 'safe' again. Wildfowl have also been shaken up a bit; more urban stretches of estuary have seen drops in numbers of the 'loafing' daytime species- some 'feeders' (such as the mud-sifting Shoveler) are nearer normal count numbers. This, to me, is a main driver. Food. Go hungry competing for resources on the estuary, or risk starting to return to an area that had seemed totally alien just a night or so prior. If you have a safe secondary loafing/roosting site, you might stick with that for a while longer.

So numbers should rebuild slowly over the next few days, but how much effect does this disturbance have on the birds at the time? Details on a radar study just over the Channel showing just how many birds are caught up in such things can be found here. Dangers during the panic flights, competing for food resources elsewhere, cautious returns over a few days to territories, all add up.

Of course, it isn't just the estuary birds- as I described last year, other roosting species take fright and flight. One example- a typical December 31st  morning watching local flightlines will see a movement of Woodpigeons from safe urban roosts out into the countryside during the first 90 minutes or so, with a minimal commute in the opposite direction. After that time small numbers start drifting back in. A typical January 1st? Exact opposite. The flight back in, I'm beginning to suspect, might not be the commuters checking the roost site is still there, but more likely the urban Woodpigeon who feed primarily in Medway gardens, returning to their favoured feeding areas.

This would all be well and good if nocturnal mass flights did suffer fatalities (they do) and if having to desert favoured feeding areas didn't put strain on survival (it does, especially in hard weather).

Many birders only notice this through rares- "I hope X hangs on into the New year" (Birders of a certain age, hoping for a revisit for a millennium tick, will remember that Aldeburgh Ivory Gull, last seen December 31st 1999).

If you haven't bothered with the Dutch radar study linked above, I'll draw your attention to one thing- fireworks can only be sold to private consumers 29th-31st December. They can only be used for recreational purposes between 18:00 New Year's Eve and 02:00 New Year's Day. How different to the British approach of starting letting off fireworks days before and continuing well into the New Year (there were more last night here). The recovery period for their wildlife is thankfully short. We just keep banging on and on.

Better get back out and see if 'my' local flocks are back to their 2016 numbers yet.