Initial ringing details of our Norwegian retrap have just been received.
8E22166 age 4 07.08.2020. Tjeldnes, Farsund, Vest-Agder, Norway
Retrapped ENR as 6M 20.07.2023. 1077days 640km 275deg
Ringing on Roan Islands
Initial ringing details of our Norwegian retrap have just been received.
8E22166 age 4 07.08.2020. Tjeldnes, Farsund, Vest-Agder, Norway
Retrapped ENR as 6M 20.07.2023. 1077days 640km 275deg
Seven recoveries for the year - which may be them all as we didn't have a good year?
One ENR to ENR retrap. 2778968 - ringed 2021 we caught 2023.
Birds from elsewhere all caught 2023 on ENR.
2715322 - from Whitburn CP, Tyne & Wear ringed 10.08.2022
2770699 - from Collieston, Aberdeen ringed 09.07.2021
2777491 - from Lunga, Treshnish Isles ringed 27.06.2023. 22days.
2674412 - from Fariad Head ringed 26.08.2011. 4344days.
2713453 - from Priest Island ringed 16.07.2017. 2223days.
2686578 - from Isle of May ringed 29.07.2015. 2913days.
Wind and rain inflenced our ringing activities more than our AI precautions did. In the end we 'lost' two nights and spent two nights on the beach - to avoid the wind. We only managed one night on what is one of our more productive sites.
To cut a long story short our captures were the worst on record for over a decade. Having taken, and expected to use, a large number of the 2500 rings taken we only managed 152 new birds, 9 UK recaptures and one Norwegian ringed bird! In any previous year we would have caught this number in a couple of hours.
Why was this? Obviously the first thing that springs to mind is AI (storm petrels being essentially pelagic may hide mass deaths at sea), however some live sampling of petrels at Mousa returned that all were negative for AI. The next option is the reported and unusally high sea temperatures. The thinking here is that the food source of plankton/krill is considerably further north in cooler waters and that petrels staying with their food source are then much (much) further from land precluding succesful breeding. As such many have not attempted breeding and are therefore not coming to land (to be caught). Let's hope this is the case, next year may be able to answer this question.
However, out of this the lower catch rate there were other benefits. Currently we are trying to build a mechanism for being able to sex storm petrels (nearly all are not). So, with lower numbers, we were able to take a full set of biometrics, photograph, examine for brood patches and take feather samples (under license) on virtually all birds to collect data which may eventually lead to guidelines for phenotypically assigning sex to storm petrels.
The Team this Year.
Following our enforced absence last year - due to all ringing activities being suspended due to Avian Influenza - we managed to get on site this year. It came with caveates though - Nature Scotland said there was to be no ringing of Great Skuas (they have been hard hit by AI), and we had to implement a biosafety procedure to ensure we didn't exacerbate any AI issues.
That said twelve of us made the journey north to continue our long-term ringing project and this year, besides ringers, we invited along several Wildlife Conservation /Entomology students.
On the island itself not much was different regarding the houses - a few walls had lost some stones and a few more roof tiles had dropped off. Elsewhere though the weather had created some bigger changes. A new gully to the sea had 'opened up' on the western edge, with much peat-slippage elsewhere, and a large section of rock had broken away from what we call the Slab-Wall (NW corner of the island) to create additional access to the rock face.These just in - a series of birds all initially caught on Nan Ron and then recaught several years later back on Nan Ron (possibly indicating all are on-island breeders). We made all of the original captures over several years, Stefan made all of the recaptures over 7-8th July 2021.
Figures show - elapsed days between captures, d, and then the (year) of initial capture. x(number) indicates a similar number of birds, two, three, and four, of same elapsed time.
David's PhD thesis is often quoted by anyone who writes about Stormies. At the time David did not have the time to publish any papers from his thesis and the thesis itself was 'old-school' i.e. still on paper so, for most, unaccessible. Over recent months Oxford University has scanned David's thesis and David himself has made it widely available to anyone who wishes to download a copy for free.
It is available at: https://ora.ox.ac.uk/objects/uuid:24973c21-ab78-42f1-a3c1-a7665b776bbf
Note that it is 35Mb in size (something like 300 odd pages).
2757508 ringed on ENR on the 11.8.2021. was recaught at Score, Highland Region, seven days later having traveled 154km - a mere 22km a day, which is a dawdle by stormie standards.