Friday 5 August 2011

Bat walk illuminates habitat wipe-out


27 people, of all ages, came out last Friday night to explore the presence of bats on Millfields, armed with bat audio detectors courtesy of our expert guide Alison Fure.

Learning about bats and bat detectors
photo courtesy David White
What we discovered was that our efforts to improve habitat in the park are being nullified by dazzlingly bright lights on the towpath at Hackney Council waste transfer station, and likewise on British Waterways land near Paradise Dock and the Princess of Wales.

Bats are found near water because the moisture keeps their wings in trim. They'll fly along rivers and canals looking for the best food spots. Big trees full of insects are ideal hunting ground for them, and woodland edge meadows with wildflowers and long grass (which we have more of on Millfields than a few years ago) also raise the insect count. But few, if any, will hunt where there is bright light. And they live for decades, so they remember the good places and steer clear of the bad.

We expected to find bats easily by the community orchard, with its canalside woodland and meadow, but there was hardly a squeak. That's not so surprising when you realise that just to the south, the towpath to Cow Bridge is as bright as a sports stadium thanks to the massive floodlights from the waste station.

The waste station lights are so devastating that we couldn't even detect bats on the opposite side of the canal, showing that the lights have driven bats out of the trees on the edge of the Essex Filter Beds wildlife reserve. It was only when we walked on the less lit section of the filter beds towpath, opposite the orchard, that our detectors picked up bats in the trees which overhang the filter beds wall. You couldn't have had a more vivid demonstration of how the lights have devastated the habitat of a protected group of species.

Too bright for bats to linger near the pub
photo courtesy David White
By Paradise Dock and the Princess of Wales, Alison said that the Daubenton's bats she found feeding here 5 years ago are no longer pausing to hunt -- they may just whiz through on their way to somewhere more congenial.

Security may be the pretext for this lighting level, but ironically it makes us less safe at night. Too much light destroys your night vision, so that when you move into a less lit area you are at a disadvantage. Moderate lighting would be more secure; and more comfortable for Paradise Dock residents trying to get a good night's sleep.

Biodiversity Officer Kate Mitchell, who helped MUG set up the walk, has immediately taken the waste depot lighting up for us with her council colleagues. Kate and MUG will also be trying to get something done about the lighting under British Waterways control.

After hearing Alison's introductory talk on bats, we could understand more fully what a loss these fascinating creatures are to the park. We were all geared up to spot this year's young bats flying with their mothers, trying to cadge a feed.

But on the bright (?) side, there are still some bats to be found on Millfields, and it's worth looking. Local resident Maggie Murray tipped us off to look on the north-east corner of the cricket field, and demonstrated how she lures them towards her by making a kind of chirruping noise. Maggie is now the Millfields Bat Whisperer -- can anyone else do this?

So please let us know if and where you spot bats. Apart from the sheer interest, any scrap of information may be useful in future battles to protect the park.

All about urban bats: The London Bat Group

1 comment:

  1. The waste depot has changed its lighting regime as a result of this. The lights by the towpath are now just switched on when needed.

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