Tuesday, 15 July 2014

200 chicks, colour ringing and Moths!

This year has been all about records. We have reached 2 milestones in the last week, we now have 208 (!) chicks on the beach with 13 eggs left to hatch and today we colour ringed our 100th chick! The numbers are extremely high and the colony is buzzing at the moment with plenty of fledglings in the air and 113 active pairs of Little Terns.
 
Colour ringed Little Tern chick © Kristina Abariute and Andrew Power (Picture taken under NPWS license)

 
This is the first year we have colour ringed Little Terns  in Kilcoole. We put metal rings on every Little Tern chick that hatches in Kilcoole (and have done so for many years) and they can be put on the chick when they are only a couple of days old as their leg doesn't change in diameter as they get older. We can only put colour rings on Little Tern chicks that are a couple of weeks old as colour rings are longer and we have to wait for the chicks legs to stretch out a bit first. Chicks start to leave the nest after 2 or 3 days so finding old enough chicks to colour ring is a little more difficult than metal ringing. At that age chicks congregate on the foreshore and, unlike their younger cousins, can run! So when we look for suitable birds to colour ring we usually end up catching a big group of them at once. The fact that we have colour ringed 100 out of 208 birds is incredible and it also gives us a good indication that many of the birds have survived the first 2 weeks, bearing in my mind that a fair chunk of the birds are not old enough for colour ringing!
  




Volunteer Kristina Abariute helping us colour ring the chicks © Kristina Abariute and Andrew Power (Picture taken under NPWS license)
 
Even though the Little Tern is a flagship species there are still many mysteries surrounding it's migration behaviour. We know they go to west Africa but west Africa is a big place and we are not certain what their migration routes are. We know that Little Terns move between sites, a dead adult tern was found last year in Baltray that was originally ringed in Kilcoole in 2010 and an adult bird was trapped on the Isle of Man last year that was also a Kilcoole bird ringed in 2010. We hope that colour ringing the birds will allow us to see the extent these birds move between sites. Colour rings are far more visible than metal rings and we hope this will lead to many re-sightings, especially considering that many Little Tern sites are actively wardened. We also hope that more re-sightings will happen along their migration routes. Most adult Little Terns are metal ringed but it is impossible to read the code from a metal ring, without catching an adult or finding a dead bird, so we don't know where they originated. This will not be the case with colour rings as the code is much easier to read but even if it is not possible to read the ring we can still get extremely useful information simply from the colour of the ring and what leg it is on. We are using green colour rings in Kilcoole with white writing on the left leg of the Little Tern. They are also colour ringing in Baltray and putting green colour rings on the right legs of the Little Tern. A colour ringing scheme is also underway in the Isle of Man where they are using yellow rings. Hopefully other tern colonies will follow suit and keep colour ringing for years to come as it should provide excellent long term data. Understanding everything about a species can be vital for determining it's conservation requirements. We can do everything we like to save a migratory species in our own country but if they are being killed in their wintering grounds it could count for very little. Hopefully this scheme will help us see the bigger picture. So remember if you see a colour ringed Little Tern report it!


Colour ringed Little Tern chick © Niall Keogh (Picture taken under NPWS license)



Kilcoole wardens Andrew Power and Darren O'Connell releasing colour ringed chicks © Niall Keogh (Picture taken under NPWS license)



And now for something completely different....
 
Stephen McAvoy paid us a visit last week and brought along his Moth trap. I was very lucky to see some real beauties before he let them back into the wild. The Poplar Hawk moth looks like it could devour a tern!
 
 Poplar Hawk-moth © Andrew Power
 
 
Garden Tiger Moth © Andrew Power
 
 

 
 
 
 
 
Andrew Power and Darren O'Connell 
 
 
 
 
 


 

2 comments:

  1. An adult Little Tern breeding in the Kilcoole colony on 19 June 1992 had been ringed by me as a chick at Gronant, north Wales, on 5 July 1989, showing interesting interchange within the Irish Sea colonies.

    In January/ February 1993, birds ringed as chicks in the Gronant and Kilcoole colonies were caught together by an expedition of Dutch ringers off Guinea-Bissau, so they obviously mix in winter quarters.

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  2. Hopefully the colour ringing sheds some more light on the movements between the Irish Sea colonies and the composition of the end of season aggregations pre-migration. It will be interesting to see what level of interchange is going on.

    It'd be fascinating to get some insight into the African end of the story, apart from the re-traps from Guinea-Bissau all we've got is a recovery from a first winter bird from Sierra Leone this year! Though that will probably have to wait for cheaper satellite tracking.

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