Saturday, 4 July 2015

The numbers are in.....great news!

Apologies for the lack of updates - most of our nests have chicks now so its absolute chaos out here, in the best way possible! Every morning and evening we spend several hours ringing chicks and taking weights and wing lengths so we can analyse their growth rates. Thankfully, this season looks to be going a bit better than last year in terms of chick survival, so fingers crossed that continues to the end of the summer!

We also found the time to do the second part of our nest census, to count all of the nests on the island, and the results are in......

Roseate Terns

Roseate Tern (picture taken under NPWS licence)

Numbers of Roseate Terns breeding here over the last two years have been levelling out a bit as the island reaches maximum capacity. With that in mind we would have been happy with similar numbers to last year's 1,250 pairs. You can imagine our delight then to get a final count of 1390 Roseate Tern nests this year!! That's the highest number every recorded here, a jump of almost 150 pairs from last year, further cementing Rockabill's importance as the single biggest Roseate Tern colony in Europe! Woo!

It's worth noting that around 90% of the nestboxes we put out have Roseate Tern nests in them, so a big thanks to everyone who has donated to the Seabird Appeal this year to help us get new boxes for future years, and to the staff and pupils of Balbriggan Community College for the boxes they gave us this year!

Common Terns

Common Tern (picture taken under NPWS licence)
 Last year we had around 2,100, and like the Roseates we have been getting the impression over the last few years that their numbers have been levelling off as all available space gets filled. This year we have 1,950 pairs of Common Terns, so their numbers here are down. Needless to say we still have a lot of them! And they still do an excellent job providing a bit of security for the Roseates. And with the amount of peck and poo attacks we're getting, it certainly doesn't seem like their numbers are any lower!! 

The Common Terns in Dublin Port seem to be doing quite well too, so despite the bit of a drop in numbers out here, they should be ok!

Arctic Terns

Nesting Arctic Tern (picture taken under NPWS licence)

 Last year we had somewhere in the region of 30 Arctic Tern nests at any one time, down from around 100 only a few years ago, due to gull predation. Unfortunately the Arctics tend to pick the rockier parts of the edge of the colony, as well as our neighbouring island ('the bill'), where they're easier pickings for opportunistic predators than if they were in the middle of the colony. We had somewhere in the region of 50 nests last week, though some of these have since been lost to gulls again. There is a ray of light though as we do have some Arctic chicks that are growing and surviving quite well. Last year we none of their eggs progressed to hatching, so this year is a bit of an improvement. We're also learning from our RSPB colleagues on Coquet Island in the UK on how to deal with the issue of gull predation, so the future should be a bit brighter in that regard. Like the Common Terns, Arctics aren't doing too bad in Dublin Port either, so fret not!

Black Guillemots

Black Guillemot (picture taken under NPWS licence)
Some of our followers might remember that last year our Black Guillemot population nearly halved due to high mortalities in the strong winter storms of 2013/14. Numbers this year are up to 60 pairs, up by around 5 pairs. A lot of young birds are likely to have died that winter, so we were expecting to 'recruit' less birds into the breeding population for a few years. Still, 60 pairs of these fantastic birds is still pretty good - fingers crossed for a few easier winters though!


Kittiwakes (picture taken under NPWS licence)

220 nests - our highest every count on Rockabill! We're delighted to have more of these fantastic cliff-nesting gulls. A lot of other colonies in the Irish Sea have noted decreases in their Kittiwake populations, so at least the Rockabill populaton is going strong.

So yay! Record-breaking years for both Roseate Terns and Kittiwakes, and not bad years for everything else. We have to send a big thanks to Peter Cutler, Jennifer Lynch, Niall T. Keogh and Dr. Steve Newton for their help over the last two weeks, both for censusing and ringing. After a few tough days you can imagine our delight when Jennifer brought us out some chocolate brownie cake, and Eoin from Skerries Seatours brought us out two Apache pizzas!! We'd like to think we've earned them!  

Andrew, and pizza!! (picture not taken under NPWS licence....)

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