Irish Little Egret turns up in Iceland! (BirdWatch Ireland)
The recently-published Bird Atlas 2007–11 has highlighted some very significant patterns and shifting trends in our bird populations over the past 20 years. For all too many species these findings reveal declines and range contractions; however there are some positive stories too. One of the most remarkable of these has been the colonisation and subsequent spread of the Little Egret. As the atlas has shown, this elegant heron is now widespread and is frequently observed throughout the country both during the winter and breeding seasons. It is therefore easy to forget that it was as recently as 1997 that the first ever nesting record was documented in Ireland, following the first British record the previous year! These events followed on from a rapid expansion of the Iberian breeding population in the early nineties, and their arrival to these shores throws up all sorts of interesting questions, such as the speculation as to whether their colonisation is linked to climate change.
Little Egret close to fledging at the Galway colony
(Photo: Dario Fernandez Bellon)
To try and learn more about the breeding ecology and dispersal of Little Egrets in Ireland, a monitoring and colour-ringing study was initiated in Co. Galway by Chris Benson and John Lusby, and this work has provided some interesting and unexpected findings to date.
The first nest sites in the county, which were established within an existing heronry on the coast of Galway Bay, were only discovered in 2009. This particular colony has since been visited every breeding season and 43 nesting attempts have been monitored. A total of 77 nestlings have been fitted with two single-letter colour rings in order to gain an insight into the survival and movements of these birds, and of these 25 (32%) individuals have been re-sighted away from the natal colony. Re-sightings have revealed that nearby Rahasane Turlough is an important area for birds from this colony to congregate before and after the breeding season, with multiple re-sightings of juvenile and adult birds reported here. Movements further afield to Sligo Bay, Kerry and Dublin Bay have also been recorded, and at least one of the birds previously ringed as a nestling has returned to the colony as a breeding adult.
The first nest sites in the county, which were established within an existing heronry on the coast of Galway Bay, were only discovered in 2009. This particular colony has since been visited every breeding season and 43 nesting attempts have been monitored. A total of 77 nestlings have been fitted with two single-letter colour rings in order to gain an insight into the survival and movements of these birds, and of these 25 (32%) individuals have been re-sighted away from the natal colony. Re-sightings have revealed that nearby Rahasane Turlough is an important area for birds from this colony to congregate before and after the breeding season, with multiple re-sightings of juvenile and adult birds reported here. Movements further afield to Sligo Bay, Kerry and Dublin Bay have also been recorded, and at least one of the birds previously ringed as a nestling has returned to the colony as a breeding adult.
Two young colour-ringed Little Egrets on their nest at the Galway colony
(Photo: John Lusby)
A fascinating journey by one of these colour-ringed egrets was recorded in October 2010, when a bird which had hatched that summer at the Galway colony was observed in the Azores, an impressive trip of 2,133km! This movement may shed some light on the seemingly erratic dispersal of juvenile Little Egrets, coinciding as it did with a particularly harsh winter in Ireland. More recently, another significant dispersal has been recorded, however this time in the opposite direction. A nestling which was fitted with a colour ring on the 4th of June 2013 was observed and photographed recently in Iceland on the 20th of October, in the company of four other birds, a journey of approximately 1,200km. Little Egrets are still very rare in Iceland and it will be interesting to see if this bird remains there or travels back to Ireland in the coming months.
The nestling on the left is the Little Egret which subsequently
travelled from Ireland to Iceland in October
(Photo: David McNichlolas)
John Lusby commented, "We think of Little Egrets as temperate or tropical birds, and so the fact that this bird travelled north at the start of the winter seems strange, particularly when the majority of other birds are all moving south at around the same time, and it is an indication that their northward advance is continuing."
Chris Benson added, "It would probably never have been suspected that any of these birds were from an Irish colony had it not been for the colour rings, and proves the value of the ringing study. We wonder when the first one will make it across the Atlantic to North America!"
Chris Benson with one of the Little Egrets that has been fitted with colour rings
(Photo: John Lusby)
This work will continue in 2014, so please keep a look out for any colour-ringed egrets and report sightings to Chris Benson at Illaune@eircom.net or John Lusby at jlusby@birdwatchireland.ie. As shown by the high number of re-sightings received to date, the rings are easy to spot, with each bird having a black plastic ring with a letter above the left knee and a yellow plastic ring with a letter/number above the right knee.
One of the colour-ringed Little Egrets photographed at Rahasane Turlough,
with the plastic rings clearly visible on its legs
(Photo: Dermot Breen)
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