Grant submissions

Last year we thought we had fully mastered the in-hand sexing of Storm Petrels. However, fresh eyes and new opinion this year took us virtually back to square one. In conclusion we consider those at extremes of morphology are sexable, while the majority sit between these extremes. In order to add full value to the birds we are catching we need to reduce the number of birds that sit in the middle. Consulting literature and those who have been handling Stormies for years we felt there was still insufficient guidance in this area. To this end we have prepared and submitted two grants, one to the Seabird Group and the other to the BOU.
In essence we are requesting funding to molecularly sex 200 Storm Petrels - this to be our gold standard. Then while birds are in the hand we shall take morphological measurements and a series of photographs which will then be analysed and interpreted (blind) to assign sex to an individual. The resultant sexing of individuals by these methods (alone or in combination) will then be compared to the molecular result in the hope of producing more detailed guidelines for sexing Storm Petrels.

Update on 2019

Time to update everyone - although I am still awaiting official notification of the six controls - three from Portugal and three from Norway.

Final totals Stormies - 1285 new birds, 124 retraps and 43 controls. (Any numerical inaccuracies indicate data on individual birds is still awaited).

Nan Ron /Nan Ron retraps - birds ringed on Nan Ron and later recaught on Nan Ron. The chart below shows the year of original ringing and the number of birds involved.

At the one extreme we have one bird that is 20 years old and at the other we recaught 40 birds that we had ringed on earlier nights during this visit. Also of note is the number of years missing which may just simply reflect the low numbers of Storm Petrels caught in those years.

Birds ringed on Nan Ron and caught elsewhere in 2019. Only three birds involved this year. Two, one ringed 2006 the other 2019, both recaught on Birsay, Orkney c88miles away (one after 4750 days, the other after 10); and the other ringed in 2019 and recaught East Side, Orkney two days later.

Birds ringed elsewhere and controlled on Nan Ron in 2019

The chart shows 20 birds. The first column is the year ringed, the second the initial place of capture and ringing, and then the elapsed time in days, and then distance, between this site and Nan Ron.

Great Skua - nine new birds caught and ringed, with 16 retraps still alive e.g. birds caught and ringed by Stefan earlier in the year.

In addition 47 nest record cards for Fulmar were submitted and all bird observations were submitted via Birdtrack.

For costs this year we used over £600 worth of rings. At this point we would like to thank John Birch for his completely unsolicited, but very welcome, contribution to ring costs.

It's not all about the birds.

A little added value is collecting data on other taxa. This year we took a moth trap (and set it in two different locations on separate nights).

Both nights were extremely productive with over 50 species of moth identified, and others still to be correctly named.
The most numerous were Dark Arches (119), Antler Moth (37) and Garden Tiger (28).

Free flying butterflies included Painted Lady (abundant), Meadow Brown (10) and Small Blue (3+). Other insects included Violet Ground and Black Sexton Beetles, Yellow Dung Fly, Marmalade Hoverfly and White-tailed and Buff-tailed bumblebees.

The Moth class in session.

Some of the science

On our visits we try and add value to everything we do. Sometimes this can be simple things like measuring and weighing birds - proxies for fitness and condition - whilst other things can start out simple but become more difficult.
One thing we thought we had mastered from last year was determining the sex of individual birds. This year we felt we had to start all over again.

The top shows what we consider to be a male, and the bottom image a female. It all has to do with the presence and extent of white under the wing. The top image shows white all across the wing with definite fringing on the primary coverts. The bottom image still has the patch of white feathers close to the body, but is lacking the extensive white fringing.

Fine you might think, but consider the next two:

Male or female?

We decided 'this' needs more work - the reference texts didn't help much either. So, next year we intend to take more photographs and remove selected feathers for definitive sexing analysis via DNA  so we can produce guidelines for ourselves and others with regards to sexing Storm Petrels. 

Ageing them is another thing altogether.....

The 2019 season

This year a team of nine travelled and were on the island from end-July to the beginning of August (five nights in total). We pitched tents in the normal spot - next to 'old George MacKays house'. The first night of ringing we were at White Cairn (which we call 'The Maze' - no idea why; see picture) and were stopped early due to heavy rain at 1.30 am. However, we still managed to capture 79 birds.

The Maze with, if you look closely, nets set and furled ready for night time captures.

The second night we were back on The Maze and managed a full night. We caught in excess of 260 birds (same night captures are not counted in totals) with two birds carrying Portuguese rings. With the wonders of technology by mid morning of the same day we had found that one had been ringed on 22nd July 2018 and the other 21st July 2019 - 38 days previously - both near Faro in southern Portugal (definite confirmation to follow).

When not ringing Storm Petrels we go off catching Great Skua chicks - simply by walking about and looking for them.

Here two skua checks have been ringed and are now being checked for body condition  and good health.

Sometimes they can get quite large, being not short of fledging. Fortunately for them, unfortunately for us, it is usually us shredding a little blood. All this walking about over the island does have its advantages. For those who have returned it reinforces just why we come every year.

The following night we reverted to a ringing site close to the camp site as, for three of us, it was their last night (as work dictated their departure the following morning). This night we caught another Portuguese bird as well as one from Norway; besides over 240 carrying British rings.

Daylight gave rise to more skua ringing - for some there first - both for bird and ringer.

The following night we were back on The Maze - with two more Norwegian birds - and then back at the camp site for our last night.
In all we managed 1285 new ringed Storm Petrels, 124 UK retraps (birds ringed at previous visits to Nan Ron), 43 UK controls (birds ringed elsewhere in the UK, details still to come) as well as the three Portuguese ringed birds and three Norwegian.
For Great Skua we ringed nine new birds and recaptured 16 rung previously in the year.

The Team:

Steph (I love my job), Bob (fixer), Liz ('gis a job), Gerry (it's not all about the birds), Danni (alleged meteorological guru), Tom (the faint smell of lynx?).
Missing because of work Josh, James and Tony.

...and in British Birds Jan 2019

In July 2008 a Storm Petrel was caught bearing a Portuguese ring. One of our group, taking photographs and with time to look, noticed what he thought was a deeper 'thicker' bill than was usual for Hydrobates pelagicus pelagicus (nominate race). It was considered it might be a H.p. melitensis - the Mediterranean form of Storm Petrel. With due diligence and reference to others more knowledgeable in the field, plus the fact that this bird had been ringed by Rob Thomas of Cardiff University on 7 July 2007 at Ponta de Almadena, and had had samples taken for DNA, subsequent analysis was able to show it was pelagicus.
Adding melitensis to the British list was not to be, bad luck Stephen, but what this article did demonstrate was the difficulty in identification that remains for this species - even the deepest-billed birds may not (necessarily) be melitensis. 

...one from Treshnish

2628978
Ringed on ENR 28.07.2014 Recpatured Treshnish Isles 28.06.2018  1431days 262km 209deg

GB recoveries (1)

All of these individuals were originally caught and ringed by us and then recaptured by someone else.

The first two were caught by us on Nan Ron in July 2017 and were both recaught the same day in 2018 on Birsay, Orkney by the Orkney RG, 361 miles away.
2716944 Caught 24.07.2018. Captured Birsay 20.08.2018
2726653 Caught 25.07.2017. Captured Birsay 20.08.2018


The following were caught over various years on Nan Ron but were then all recaught by Scott (on Nan Ron) this year. Ring number followed by year of ringing.

2611976 (2008)
2629461 (2009)
2658454 (2010)
2659592 (2011)
2682205 (2013)
2682974, 2696979 (2014)
2716007, 2716291, 2716129, 2717031 (2015)
2716932, 2716897, 2716798, 2726501, 2726747, 2726656, 2716766 (2017)

2018 catch-up

I don't have final figures yet for 2018 as I'm still waiting to find out whether some of the birds we caught were either retraps or controls but we will be looking at about 740 new birds ringed.
I do however have some recovery data on those records submitted to date.
Firstly, this post, three late reported Norwegian recoveries.

8E29782
Caught 24.08.2013 Flem, More og Romsdal, Norway
Captured 27.07.2014 ENR
337days 736km 232deg

8E29909 (second ring added 2700571)
Caught 25.08.2013 Flem, More og Romsdal, Norway
Captured 30.07.2014 and 01.08.2014 ENR
341days 736km 232deg

ED00253
Caught 24.08.2013 Hamnaholmen, More og Romsdal, Norway
Captured 31.07.2014 ENR
341days 674km 233deg