Friday, 12 April 2013

Let the ring-reading begin!

I spent a day last week trudging around the parks, pitches and beaches of Dublin looking for colour-ringed Oystercatchers, hoping to read as many rings as possible, knowing that it’d be one of the last chances I’d get before they head northwards to breed in the coming weeks. I was well prepared for the cold weather, but it turned out to be a very pleasant day with good spells of bright sunshine, which made ring-reading a joy. I managed to get 32 rings over the course of the day, including some that hadn’t been read before.

These colour-ringed birds are now individually recognisable and their rings can be read with a telescope or camera from hundreds of metres away (i.e. without the need for recapture). This allows us (and you) to record the movements of the birds throughout Dublin Bay and beyond. An analysis of these movements will allow us to determine key foraging and roosting areas in Dublin Bay as well as unlock mysteries about how birds are affected by things like disturbance and adverse weather.

The re-sighting effort began the day after the catch day (see March post), and since then, we’ve notched up a total of 123 re-sightings. Thanks to numerous enthusiastic ring-readers, 87 out of the 119 colour-ringed birds have been re-sighted. While the majority of these have been in the vicinity of the ringing site on Sandymount Strand, a small number of birds have been recorded numerous times on various parks and pitches in south Dublin. Early indications suggest that some birds have St. Michael’s College rugby pitches in Ballsbridge on their daily itineraries, while other birds seem to head elsewhere for their earthworms. It’s up to you to fill in the gaps on this!

The remainder of the wader roost at the Merrion Gates spit that 
held thousands of waders during the winter. Richard Nairn

We’re calling on you to make a special effort to read the inscriptions on these rings and report them to us. Even reports of colour-ringed birds where the inscription could not be read are useful. Although wader numbers are really dwindling in Dublin Bay at the moment, as birds head off to breed, there’s still some time to tick off another couple of colour-ringed individuals.

With this type of project, there really is no such thing as too much information! The benefit of having 119 individually recognisable Oystercatchers in Dublin Bay cannot be underestimated - these birds can tell us so much about what they do, what they need and how we can effectively protect and conserve them. But a solid database of re-sightings is the foundation on which everything else can be built.  

I was delighted to see the re-sightings flying in as soon as the project was launched on the BirdWatch Ireland website, so keep up the good work! It’s great getting all the re-sightings into the database and generating the re-sighting reports for each of the birds. At this stage, the “re-sightings histories” that we send to ring-readers only go back a number of weeks, but we have to start somewhere! With plenty of ring-reading, these re-sighting histories will become more and more interesting!

Three colour-ringed Oystercatchers on Sandymount Strand. John Fox

I think there is something very intimate about knowing the movements of individual birds around my local parks and beaches. But perhaps more importantly, reading the rings on these birds makes a contribution to conservation science and allows us to learn about how these birds use Dublin Bay and how we can work to ensure that they always will.

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