Saturday 19 March 2016

Jelly for Dinner!

When you spend three months living in a seabird colony you're never bored! As similar as some days are, there's always something new to be seen if you keep an eye out. Something quite interesting and somewhat unexpected is the interaction between Terns and Jellyfish on Rockabill, and we've just had our observations on this published in the latest edition of Irish Birds - Birdwatch Ireland's scientific journal.


Essentially what we've observed over the last few years is that some of our Terns have been targeting Lion's Mane Jellyfish for food - but not the jellyfish themselves, but small fish that associate with them and shelter beneath them. It's something that has been recorded in a few species in various locations around the world, but not in Terns in Ireland or the UK.


Lion's Mane Jellyfish on Rockabill, as seen from outside the water. (BB)

Lion's Mane Jellyfish on Rockabill, as seen from underwater! (AP)

The series of pictures below, taken under NPWS license by Andrew Power, show an Arctic Tern plunge-diving over a Lion's Mane Jellyfish at Rockabill in 2015, trying to catch the small fish beneath it.






The most recent edition of Irish Birds also includes papers on Black headed Gulls feeding on mayfly, colonisation and breeding status of the Great Spotted Woodpecker in the Republic of Ireland, reproductive output of Hen Harriers in relation to wind turbine proximity and the regular rare breeding bird report for 2014 and 2015, Irish rare bird report, 2014, Irish Ringing report for 2014, and results of the International Swan census in Ireland, January 2015 as well as other papers and notes

Irish Birds Vol 10 number 2, 2015