April Fowl

As spring is (almost) turning to summer, there is also a transformation in the bird life of Dublin Bay. Having spent the winter taking bi-monthly counts of the birds at Bull Island, I have watched the birds in the lagoon shift with the seasons. Not only are new species arriving and others heading off around the world, but the appearance and behaviour of certain species is adjusting to the warmer season.

The difference most apparent to me were birds coming into their colourful summer plumage, which is generally much more striking and attractive than winter plumage (and makes identifying species at distance a much faster task!). Many of the Black-tailed Godwit have already traded their plain brown winter plumage for vibrant rufous-orange on the neck and black barring on the breast. Similarly, Dunlin become a rich chestnut with a prominent black belly patch, rather than their wintertime grey-brown. The Black-headed Gulls finally live up to their name and develop a striking chocolate-brown head for the breeding season. This emergence of birds in full breeding plumage signals the birdy courtship season is in full swing and summer is truly on its way!

Black-tailed Godwit in breeding plumage (Andrew Kelly)

 Black-headed Gull living up to its name (Oran O’Sullivan)

Dunlin in summer colours (Ken Kinsella)

The change is not only in appearance but also, of course, in behaviour. As their migration departure is approaching fast, the Brent Geese at Bull Island are frantically building stores to see them through the journey. Since they have spent the winter gorging all the eelgrass and algae in sight, by spring Brent Geese must look for something new to devour. In the last month I have observed more geese feeding in the grass around the lagoon instead of the intertidal zone within the lagoon. Early in winter, the geese feed on eelgrass and algae at low tide, but when all of it has been eaten away, they begin to graze grassland. This reflects how the change in vegetation through the seasons influences the bird life, as some sources become depleted and others are made available.

Perhaps the most significant change through the seasons is inward and outward migration to and from Dublin Bay. By late April, most of the over-wintering species have left Ireland and summer species are arriving. I have noticed a reduction in wintering species’ population numbers at Bull Island during April counts, as migration to their summer grounds gets underway. Smaller numbers of Sanderling, Knot and Turnstone meander around the lagoon, while Wigeon and Teal in particular have disappeared off my radar. But the upside to the absence of these birds are the arrival of summertime species to Bull Island. I spotted my first two Sandwich Terns of the season pottering around the lagoon just last week - something that screams “summer is here!!” in my face.       

While my bird counts at Bull Island are finished for this winter season, the spring transformation is set to continue. More summer species, such as the remaining Terns, will arrive, and those Brent Geese inhaling the grass will abscond to Canada. Hopefully this summer will be a kind one to our breeding birds and next winter’s monthly counts will show positive results!

Susan Doyle

March: In like a lion, out like a lamb…or did we get that backwards?

We have seen the end of March, and Spring is in full swing throughout Dublin Bay. Our schedule of bi-monthly surveys have allowed us to see all the changes that happen across the month, and at this time of year, Dublin Bay becomes an airport terminal, with passengers arriving a departing from far and wide.

In the past few weeks, bird numbers throughout the bay have been steadily decreasing, as waterfowl, waders and gulls take flights to their breeding grounds. The Teal will end up in Iceland, northern Europe and Russia; the Knot will head for Greenland and Canada, after staging in Iceland or Norway; and the Black-headed Gulls will spread out again right across northern Europe.

On the ground, the sound of wee-oo-ing Wigeon is replaced by the coor-eee of Whimbrel passing through on their way northwards having wintered on the West African coast. On Bull Island, singing Skylarks nearly drown everything else out, but what a welcome sound it is. And there has been a Meadow Pipit singing his heart out over the spit at Merrion gates too.

These days, the project team open our inboxes each morning in anticipation of getting emails from northern climes, bringing news of Dublin-ringed Oystercatchers, Redshanks and Bar-tailed Godwits en route to, or on, their breeding grounds. Last week, we heard from Ian Durston from Nairn in Scotland who has one of our birds breeding in the field next to his house. XI has taken up residence in a stubble field in Cawdor, Nairn and seems to have paired up, so it may not be too long before he hears the pitter-patter of tiny …cockle-stabbers.

XI and mate in Nairn, Scotland Ian Durston

The Brent Geese are preparing for their imminent departure, before re-fuelling in Iceland, crossing the Greenland Icecap and finally arriving in Artic Canada. Soon there won't be sight nor sound of them until they return in September. But now we're on standby for the arrival of the breeding terns. Sandwich Terns tend to take an earlier flight than the rest, and handfuls have been seen already, but it’s the Common and Arctic Terns that we’re waiting for. Their harsh and rasping screechy calls will herald the onset of summer fieldwork, and trips to the Port to ring the chicks and monitor the breeding success of the colony. 

So, there's plenty to see in Dublin Bay - it's an ideal time of year to get out and see migration for yourself, to observe the comings and goings of spring. 

Ecologists strike it lucky!

BirdWatch Ireland’s waterbird ecologists working on the Dublin Bay Birds project spend a lot of time on Sandymount Strand and have struck it lucky with a remarkable discovery.

A sea-front curtain-twitcher remarked:

“They seem to be here all the time! I’ve seen them here at all hours of the day and night – with their telescopes watching the birds, catching them and marking them with plastic leg rings, or even tracking the Oystercatchers with radio-antennas, so it’s little wonder that they were the ones to find the gold.”

“When I saw the low rainbows, I started to think about their significance,” said one of the project team, who also has a keen interest in Irish folklore. “My grandfather comes from Slieve-an-ore [Gold Mountain], near Feakle in Clare. He has seen the low rainbows there too, and told me what they mean. Tales of leprechauns and pots of gold are not just bedtime stories, despite what people may think.”

Squally showers on Sandymount Strand Niall Tierney

The ecologist continued:

“We managed to get some spades and sieves from colleagues in nearby UCD and got straight to work. It’s not rocket-science – it’s simply a matter of scouring the sandflats looking for signs of mineralisation, and then getting busy with our spades and sieves. The gold pellets are pretty obvious, once you get your eye in.”

Sifting through the sediment Niall Tierney

Others have suggested that the gold may originate from one of the many shipwrecks in Dublin Bay and that it may just be washing up now, after the storm force gales of Monday night. The steamship RMS Leinster, which was torpedoed by a German U-boat UB-123 on the 10^th October, 1918, is emerging as the prime candidate, as military historians have long speculated on the likelihood that she was carrying a significant cargo of gold.

Whatever the source of the gold, it’s expected that, much like the infamous 19^th century gold rushes, people will flock to the Dublin coast aspiring to make their fortunes.

Susan and Helen make their way back with their loot Niall Tierney

BirdWatch Ireland has remained tight-lipped about how it will spend its windfall. However, a source close to Ireland’s largest nature conservation organisation suggested that the money will either be spent on an ambitious plan to create the world‘s largest aviary by roofing Co. Wicklow, or on a Passenger Pigeon re-introduction project, which aims to solve the world’s hunger crisis. 

Coláiste Íosagáin meets Dublin Bay's birds

We were delighted to have the opportunity to meet with the students and teachers from Coláiste Íosagáin, Booterstown recently. The outing was part of the science curriculum focusing on local biodiversity and habitats, so it was an excellent opportunity to spread the word about our research on the waterbirds in Dublin Bay and the habitats upon which they rely. 

Ricky meets with Coláiste Íosagáin students
 at Booterstown Marsh Neasa Ní Ghallchóir

On the day, three 2nd year classes visited Booterstown Marsh and identified the ducks and waders feeding in the nature reserve. Later we visited Sandymount Strand to see some of the birds that prefer to feed on the sandflats and along the tideline.

We also did some radio-tracking, which proved a big hit! We’re currently tracking ten Oystercatchers to work out their foraging and roosting habitats during the day and at night, and with the girls’ help, we were able to get a few more fixes for the database. 

Getting a closer look at some Redshanks 
Neasa Ní Ghallchóir

We all got a chance to see a great variety of waterbirds on the day; everything from the vegetarian, grazing Brent Geese to the carnivorous, probing Dunlin, and learned all about their adaptations and foraging strategies. Other topics covered included disturbance, migration, population trends and conservation issues.

The girls have a go at radio-tracking 
Oystercatchers Neasa Ní Ghallchóir

A big thanks to all the students and teachers for an enjoyable morning chatting about the importance of Dublin Bay for birds and biodiversity. It was heartening to meet students who were both interested and well-informed about the natural environment around them. I wonder if the children at our Oystercatchers’ breeding grounds are as well informed. …Maybe we’ll have to plan a trip to Iceland, the Faroe Islands, Norway or Scotland to find out! ;-)

Dining on Dublin's Docks

Brent Geese have become a very familiar site in Dublin City in recent years often turning up in all sorts of places.Our thanks to Richard Nairn of Natura Environmental Consultants for his insight into the movements of Brent Geese within Dublin Port.

"Brent Geese are now using the inner parts of Dublin Port on a regular basis.  As the winter progresses,  their natural food resources such as eelgrass and green seaweeds become scarcer on the mud and sandflats throughout the bay. The geese seem to have been forced to seek out other feeding areas including golf links, sports pitches and public parks with over a hundred such sites now used around the city.  A recent development has been the tendency of some geese to favour feeding on spilled agricultural products on the quaysides in Dublin Port.   

Feeding flock by the quayside - Richard Nairn

They swim on the River Liffey or in the Alexandra Basin (a deep mooring area for large ships within the port) until any disturbance has passed and then fly up onto the quays where they feed intensively on maize and soya meal among large flocks of pigeons and smaller numbers of gulls.  So far as we are aware this behaviour has not been recorded anywhere else in their range which includes sites in Canada, Iceland and throughout Ireland. I have been monitoring these geese closely over the last few winters and  peaks of up to 450 geese using this source of food have been recorded. 

Brent Geese next to Alexandria Basin - Richard Nairn

 Among them are some colour-ringed geese and the large numbered codes on these rings show that a core group of up to ten individual birds are using the Port on a regular basis, including over several winters.  This suggests that some geese have learned to exploit this food and others then follow them in to share the spoils.

Ringed Brent Goose - Richard Nairn

You can follow the fortunes of the geese on the blog posts of the Irish Brent Goose Research Group at http://irishbrentgoose.blogspot.co.uk/."

Sorry about Knot blogging recently…

This week we received word of two Knot ring recoveries from the BTO. These birds were found dead at two separate locations on islands in the Wadden Sea on the northwest coast of Germany.

Wadden Sea Wikipedia

The Wadden Sea spans from The Netherlands along the coast of Germany and to the western half of the Danish coast. It’s an area well known to ornithologists as many species of waders, geese and ducks winter there, or use it as a re-fuelling or moulting area on their migration. 

The birds were cannon-netted and ringed on 30^th January, 2014 at the Merrion Gate Spit on Sandymount Strand in Dublin Bay. 

Ringing (blue) and recovery (yellow) locations for the two Knots

The first bird (ST40506) was found on 24^th July on the island of Helgoland, a total of 932 km from Dublin Bay. Helgoland is well known for its bird observatory and gives its name to a style of bird trap used to catch birds for ringing. The island is in the middle of a major migratory thoroughfare, so is superbly well placed for studying bird movements. 

The second bird (ST40507) was recovered on 12^th August, 962 km from Dublin, at Sylt Island just off the German coast. This sandy island, connected to the mainland by a causeway, supports thousands of waterbirds each winter. 

Sylt Island, Wadden Sea, Germany Wikipedia

As both birds were described as “long dead” by the finders, it is most likely that these individuals perished on their way to their breeding grounds. They were most likely fuelling up in the Wadden Sea before making a two-step journey to their breeding grounds in Greenland and High Arctic Canada. 

Knot in breeding plumage during spring staging
in northwest Iceland Jan van de Kam

From previous ring recoveries and re-sightings of colour-ringed birds, we know that the Knots in Dublin take alternate routes to their breeding grounds; some stopover in Norway and others stopover in Iceland. We’re delighted to get information on ring recoveries like these as they allow us to shed more light this intriguing situation.

Time for thermals, the Brent Geese are back!

The Brent Geese have arrived, so there is no denying winter is well and truly here. During a count on October 17^th, the Irish Brent Goose Research Group (IBGRG) had a tally of 23,500 at Strangford Lough, which accounts for a substantial proportion of the East Canadian High Arctic population. Most of the birds tend to stage in Strangford before filtering down to the rest of the country, and we tend to get about four of five thousand in Dublin each winter. 

Light-bellied Brent Flock IBGRG

We had about 40,000 birds across the country when they were surveyed last, in 2012, and as this accounts for such a large part of the flyway population, it means they are an important conservation priority for us. All our eggs in one basket and all that…

Sorry about that. Anyway...this year the first arrivals were right on cue, with birds being reported at Kincasslagh, Co. Donegal on September 5^th. The first local record came two days later when, Cian Merne reported two birds at Bull Island on the 7^th.

Dublin’s Brent Geese have adapted to sharing Dublin Bay with the 1.3 million inhabitants of our capital. They are attracted to the expansive intertidal mud flats, where the gorge on their preferred food, Zostera (Eelgrass). Once the Zostera has all been nibbled away, they switch to green algae or else make a move to recreational grasslands around the coast. So, later on in the season, they can be found well inland, on pitches and parks right across the city.

Brent flock feeding in McAuley Park, Dublin IBGRG

Brent Geese have for many years been the subject of an intensive marking study carried out by the IBGRG. In any given group you may spot colour-ringed birds, which are often easily readable with binoculars. All re-sightings should be reported to grahammcelwaine@btinternet.com , but keep a weather eye out for birds with red and blue rings. These birds will have been ringed on their breeding grounds in High Arctic Canada! Some of the research group spent the summer catching geese up there and have some amazing stories to tell.

So, make sure to wrap up, grab your binoculars and get out and have a look around your local patch for all the new winter arrivals.
 

For more info on these little geese check out the excellent IrishBrent Goose Research Group Blog.