Eggs, pegs and chicks with legs.

It's been a busy auld time around here on Rockabill as of late. We've had  a lot going on with visitors from Coquet Island being drafted into help with our Geolocator Tagging Study of roseate terns and also the epic task of censusing this here small but nest-packed island.

A retrieved Geo-locator tag (centre left of photo), records light level which can be used to calculate the latitude and longitude of the bird over it's long-distance migrations to and from West Africa.

Coquet Island is another tern colony located just off the coast of Northumberland, Northern England in the North Sea (https://www.rspb.org.uk/our-work/conservation/projects/coquet-island-seabird-sanctuary/). It hosts an impressive seabird colony hosting nesting birds such as: roseate, common, arctic and sandwich terns, black-headed, lesser black-backed, herring gulls, eider ducks, shelducks and more! The colony is taken care of by the RSPB, and Coquet island, like Rockabill, is also parts of the EU Roseate Tern Life Project.  (http://roseatetern.org/index.html).

Dr. Paul Morrison, Ibrahim Alfarwi (PhD candidate) and Dr. Stephen Newton landed on the Rock last Monday the 11th and after a brief coffee were put straight to work as we assembled our team and began the eggceptionally herculean task of finding every nest on the rock, counting every egg and marking all the nests. We searched through every patch of tree mallow, mayweed and scurvy grass as well as considerable number of nooks and crannies and 843 nestboxes. We were not disappointed! In total this exhaustive search yielded 1473 Roseate Tern nests, 1851 Common Tern nests and 63 Artic Tern nests.

After the initial census of Rockabill was completed it was time to re-trap all of the roseate terns that were initially tagged with Geo-locators last year. Ibrahim manned the hide on the south side of the island overlooking the nestboxes of the geo-locator birds, waiting patiently for birds fly in and out of boxes revealing their tags and relaying info to Dr. Steve and Paul who then caught 12 out of 20 of the tagged birds, a great result, though we hope to get some more in the near future when the boss man returns.

Steve attentively removing the Geo-locator tag while Paul takes note of ring and biometric data for a roseate tern. Image taken under NPWS licence.

Steve measures the wing length of a roseate tern. Image taken under NPWS licence.

Ibrahim and Paul out checking boxes. Image taken under NPWS licence.

Paul and Steve out retrieving tagged birds. Image taken under NPWS licence.

Now that everyone has left and Steve has headed for sunnier shores to liase with other members of the LIFE Project in the Azores as they visit the second largest Roseate Tern colony on this side of the Atlantic, time for the second census where the three of us will take on the challenge again and find the last of the nests. We're currently mid re-census and the numbers just keep climbing! Stay tuned for a final tally on the Rockabill Terns.

Oh and in other news are eggs have begun hatching en masse with many sorry little wet creatures emerging for the first look at the world but it doesn't take too long for them to dry off and tern into fluffy cute chicks that would just make your heart melt! It won't be long until these tiny cuties start legging it all around the place in force, in fact it's only going to be a day or two. Anyways that's all I got for now but we'll back again soon with more updates. Though if your bird senses are twitching and you're still looking for your fill on Rockabill life please check out the Instagram page "Birds_bats_and_beyond" for pictures of bird-life on the Rock (not affiliated with BirdWatch Ireland or anyone/thing else for that matter, all views my own if there even are any and please excuse this shameless self-promotion :D )

Two common tern chicks (Left:2 days old, Right 1 day old). Image taken under NPWS licence.

David Miley &
The Rockabill Team

Egg season

Yes, full egg season is upon us. Rockabill is teeming with eggs. Some of our main species, Roseate (Sterna dougallii) and Common (Sterna hirundo) terns have now laid their second and third eggs, respectively. Arctic terns (Sterna paradisaea) and Black Guillemots (Cepphus grylle) are also on their way and Black-legged Kittiwakes (Rissa Tridactyla), have just started… we still see them traveling around for some algae as nesting material, but some eggs started popping out!

Common tern (Sterna hirundo) with a three-egg clutch during nest checks. Photo taken under NPWS licence.

 Common terns get extremely protective and aggressive during this period. We miss the days we could walk the island peacefully! Now we are being attacked left and right, they peck our heads, our hands, poop on our heads and let’s admit it, sometimes on our faces too and scream in our ears. You have to admire their courage! They will do everything to protect their potential offspring. As Tim Birkhead says: “eggs are the most beautiful thing” indeed! Females invest so much on them, all their nutrients in the prior weeks before laying, the energy during the incubation period (shared by both partners in this case) and in protecting them from predators. During the process of egg laying, males will feed females. It is a funny thing to watch males coming into the colony holding fish in their bills and trying to find their partners. When they do find them, they sometimes still seem to tease them a bit before they actually feed them. I can definitely identify with the “hangry” (hungry + angry) females annoyingly screaming until fed, and sometimes after too, begging for more! Common terns normally lay 3-egg clutches in open nests on the ground. Roseates, on the other hand, generally lay 2-egg clutches in the wooden nest boxes provided, but that’s not to say that some Roseates will not lay open nests or just have the nutrients or energy for a single egg. Reproduction is a serious investment in the life of a seabird. If a bird needs to prioritize its own body condition of if reproducing during that season does not look favourable, for external factors, a bird will likely skip a reproductive year and try again the following season.

Roseate terns (Sterna dougallii) can be seen incubating eggs inside nest boxes provided. Photo taken under NPWS licence.

During egg season, one of our main worries is to keep the island predator free. Luckily here on Rockabill, we do not have to worry about any rodents (they would probably keep me off the island too!), but we do need to worry about gulls and birds of prey, especially Great Black Backed gulls (Larus marinus) and Peregrine falcons (Falco peregrinus). If given a chance, they predate on nutritious eggs, and sometimes on adult birds too, leaving a trail of destruction. For that, we have a gull scarer device, which plays distressing calls to keep gulls away, and we also do 5 AM shifts, when we try to keep the colony patrolled and busy and scare any attackers with our presence :)

Roseate egg predated just outside the nest box, likely by a Great Black Backed gull (Larus marinus). Photo taken under NPWS licence.

We are hoping for a very productive season, with many fledglings successfully leaving us at the end.  For now though, you can find us counting eggs around, under the Irish sunshine, wearing the most exotic three-layer head attires :)

That busy dinner hour! Common terns (Sterna hirundo) enjoy the Rockabill sunset while waiting for that take away fish :) Photo taken under NPWS licence.

Until next time,

Heidi Acampora

& the Rockabill team