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| Bridled tern - a bird with a call note like that of a wader |
THE latest birding 'frenzy' has focused on the coast of Northumberland where a bridled tern has been watched circling the lighthouse on Coquet Island (and occasionally landing on it).
The alert was sounded on Saturday evening when ranger Holly Pickett tweeted: "Found this stunner of a bridled tern on Coquet Island today, getting slightly harassed by arctics (arctic terns) but landed for a brief second and gave us lots of circuits of the lighthouse as the sun set. Well chuffed."
Hats off to Holly! She found and identified the rare tropical visitor
Since then, hundreds of birders have been on the scene - either booking seats on the Puffin pleasure boat which approaches Coquet Island from Amble - or making do with distant views.
Although the bridled tern is believed to be expanding its range as a result of changes in ocean climate, it remains a bird of tropical or sub-tropical seas, and there have been few records for British waters.
As of 1958, British Birds journal had registered just three "beach-drifted" birds - at Dungeness, Kent (November 19, 1931), at North Bull Sanctuary, Dublin (November 24, 1953) and at Three Cliffs Bay, Gower, Glamorgan (September, 1954).
Fast forward to the same journal in October 1981 where it reports that, on May 28 1979, "R.Heywood heard what he thought was a soft wader-like call on Inner Fame in the Fame Islands, Northumberland.
"On turning, instead of the expected wader, he saw a dark tern with a sharply defined white forehead, unlike any of the other terns on the islands."
The report continues: "After several minutes' observation, the other wardens, A. E. Dixey, A. Ferguson, D. E. Mole and A. R. Taylor, were contacted and field notes taken.
"The bird's flight was distinctive, with slower, much deeper wingbeats than arctic or common Terns, the emphasis very much on the down beat. It was agreed this was a most striking bird with very distinct features."
After consulting the available field guides, they concluded that the bird was a bridled tern.
In its own commentary of the latest sighting, Bird Guides writes: "A healthy gathering of people were able to connect with the bird as they viewed distantly from the mainland at Low Hauxley, near Amble, approximately 1.3 km away.
"However, closer views were had by a lucky few who managed to book themselves on to the Puffin Cruise around the island."
It continues: "Last year's adult in Gwynedd was wholly erratic in appearances during its four-day stay, so a repeat of the summering adult on the Farne Islands in 2013 and 2014 would go down a treat."
Meanwhile, back in 2015, in the Journal of the Royal Society of Western Australia, there was an interesting report - headed Recovery of seabird colonies on Rat Island following the eradication of introduced predators.
In their article, the authors describe how the island, located off Perth, was a focus of guano mining between 1885 and 1915.
The enriched soil that lay beneath the guano was extracted (by Chinese labourers), conveyed to a coastal access point and shipped by ferry to mainland Australia.
The activity resulted in the introduction of both rats and cats which resulted in the extirpation of nesting seabirds such as fairy terns and bridled terns.
As part of a biosecurity measure aimed at preventing the spread of Ratus ratus and Felix catus to neighbouring islands, both species were gradually eradicated from the island - the cats by lethal trap and the rats by the poisonous anti-coagulant, Pindone, which was laid in plastic bags at strategic locations.
The project started in 1991 and concluded in 2000.
Subsequent monitoring revealed that, following their return, the six breeding pairs of bridled terns nesting on the island in 2003 had risen to between 50 and 100 pairs in 2008.
Most of the nests were detected under rock piles left by the guano mining.
The report states: "Bridled terns prefer to nest under cover (provided in this case by the mined rock-piles), have high nest-site fidelity and are a common nesting associate with other dark terns, including sooty terns.
"As such, the consistent presence of breeding bridled terns on Rat Island from 2003 may have facilitated sooty tern settlement by breaking down the 'information barrier' with respect to colony predator security."
* Top photo: Bridled tern by Aviceda via Wikimedia Commons
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| In demand, these are busy time for Puffin Cruises which sails out of Amble |
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