Sand martins storm in to colonise new dunes
Storms battered our coastline throughout last winter - but one bird is reaping the rewards.
Until last year there was only one sand martin colony on the Bann estuary, but this summer the returning migrants have founded new colonies on fresh sand cliffs carved out by the storms.
Sand martins nest in tunnels in sand cliffs, quarries and river meanders, all of which are vulnerable to human change.
Toby Edwards, site manager for Portstewart Strand, said the only piece of real estate where the birds could nest was a "jam-packed" sand cliff on a small river bend on the west side of the estuary, but now they have founded two new colonies on the new cliffs carved out on the eastern shore.
"The fresh sand dune cliffs are still settling but so far we've counted 19 new tunnels at two sites, both carved away by the winter storms, creating a new horseshoe bay close to the river mouth and extending the 'Wee Bay' that, post -storm, isn't so 'wee' anymore," he said.
"The movement of the sands are all part of natural processes which can be damaging for some species, but good for others."
Last winter high tides combined with storm swells to push the waves up to two metres higher than normal and this dredged away large quantities of sand dunes around our coastline.
Portstewart Strand and Downhill beach form a 'closed cell', where any sand eroded is pulled several hundred metres offshore, but doesn't leave the immediate area.
"All that cliffing is gone now because the sand has been working its way back in over the summer," Mr Edwards added.