199 MANX SHEARWATER CENSUS 6 5 : 1 8 8 - 2 0 1 5.1.2 OCCUPANCY RATES 5.1.2.1 OCCUPANCY RATES 2021 CENSUS (AREA C) Burrow occupancy rate for Area D in 2022 was 89.59%; this was a 9.81% decrease on 2015 (there was a lack of data collected in 2009). The reduction in occupancy rate would suggest prospecting birds are digging new burrows. Table 4 Occupancy rates during the 2022 census (Area D) compared to 2015 and 2009. Area D total 2022 2015 2009 % change % of burrows occupied 89.59 99.33 N/A 2015 – 2022 -9.81% 5.1.2.2 OCCUPANCY RATES 2022 CENSUS (AREAS A+B+C+D) Looking at the four areas (A, B, C and D) surveyed during this current census and comparing with the 2008-2010 and the 2014-2016 censuses we see that the occupancy rate has fallen slightly (-1.83%) from the 2014-2016 survey but is still higher (+4.88%) than the 2008-2010 survey. Table 5 Occupancy rates of Areas A, B, C and D in 2019-22 compared to 2014-16 and 2008- 10 Area A+B+C+D 2019-22 2014-16 2008-10 Number of burrows 28,884 18,539 14,755 AOBs 26,423 17,276 12,870 % of burrows occupied 91.48 93.19 87.22 2014-16 – 2019-22 -1.83% 2008-10 – 2014-16 +6.84% 2008-10 – 2019-22 +4.88% 5.1.3 RESPONSE RATES The number of birds that responded to voice playback in 2022 was much higher than 2019, but close to the 2019-2020 results. From the 5301 burrows, responses were elicited from 1714 (36.09%). Table 6 2019-2022 Manx Shearwater surveys on Bardsey including x2.39 correction factor applied . Number of burrows AOBs % of burrows occupied Playback responses (from AOBs) % of responses from AOBs Responses x correction factor (2.39) Area A 3550 3078 86.70 1432 46.52 3422 Area B 8532 7969 93.40 2496 31.32 5965 Area C 11501 10627 92.40 1438 13.53 3437 Area D 5301 4749 89.59 1714 36.09 4096 All Areas 28884 26423 91.48 7110 26.91 16993
200 BETTERIDGE REP. BARDSEY BIRD FLD OBS. 5.1.4 CORRECTION FACTOR 5.1.4.1 METHOD In 2020, a sample of 39 burrows known to be occupied were visited to elicit a response from the occupant using voice playback on five separate occasions (Prettyman 2020). The average response rate from these five visits was then used to calculate a correction factor, which could then be applied to all the voice playback results in order to estimate the total number of occupied burrows. 5.1.4.2 RESULTS The response rates from 39 burrows varied from 35.9% to 61.54%, with an average of 43.82%. The correction factor across each of the five visits varied from 1.63 to 2.79, with an average of 2.39 which is used as the correction factor. 5.1.5 IMPROVED AUDIO QUALITY AND DUAL-SEX CALLS It is well documented that male Manx Shearwaters have a response rate of 93-98% to calls of other males during the breeding season and that females respond less than 1% of the time to the call of a male (Perkins et al. 2017). As mentioned previously, dual-sex calls were used in the 2019 to 2022 voice playback surveys on Bardsey as a direct result of a study by Perkins et al. (2017) which found that females respond at higher rates to calls of another female compared to male-only calls. The response rate of AOBs decreased significantly from 46.52% in Area A in 2019, to 31.32% in 2020 for Area B, and even more so to 13.53% for Area C in 2021. However it increased in 2022 to 36.09%. There appears to be no obvious reason for birds on the northern part of the eastern side of the island not to respond at the same rate as birds on the western side. However, the response rate in Area C in 2021 of 13.53% was very similar to a sample in the same area in 2015 (12.11%). During 2015 and 2016 a test was carried out using the iLuv speakers and iPods to try to elicit responses from incubating birds in 30 study burrows. Over a 14-day period, each burrow was surveyed four times following the same voice playback methodology as used in the 2008 and 2014 censuses (25 seconds of playback using male-only calls, followed by a 25-second listening period). Given that the process occurred over a 14-day period, both males and females should have been incubating eggs in burrows at different times during that period and so a response rate of ~50% was expected. Consequently, it was surprising to find that the response rates varied from c15-25% (pers. obs./Stansfield and Leatherbee - unpublished data). As previously stated, the 2022 results saw a slight increase in responses compared with 2015, presumably due to the methodology (dual-sex playback) along with the equipment used. The new EasyAcc Mini Bluetooth Speaker and digital MP3 dual-sex recording of Manx Shearwaters produced a much better sound quality at a greater volume; the improvement in sound quality alone could be expected to improve the likelihood of a bird calling back to it. It is unclear, however, as to why the response rate was much lower than in 2019 and 2020. 5.1.6 OTHER OBSERVATIONS AND CONSIDERATIONS Due some complications/difficulties that were experienced during 2021 with the survey due to Covid-19 the number of burrows and AOBs in Area C will be re-counted in 2023 in order to clarify the accuracy of data. The results of the 2019 to 2022 surveys suggest that Bardsey’s Manx Shearwater population is still rapidly expanding and that the island’s carrying capacity for nesting Manx Shearwaters has not yet been reached.
201 MANX SHEARWATER CENSUS 6 5 : 1 8 8 - 2 0 1 The productivity rate for Manx Shearwaters was 77% in 2022, meaning that a minimum of 20,345 chicks could have hatched. If we add this to the estimated 52,846 breeding adults, then there may have been as many as 73,191 Manx Shearwaters on the island during the summer months (excluding non-breeders). 6 SUMMARY The results from the 2022 survey suggest that the population of Manx Shearwaters on Bardsey has rapidly increased in this section of the island. A total of 5,301 burrows (occupied and unoccupied) were counted across the 2022 study area. Of these, 4,749 (89.59%) were deemed to be Apparently Occupied, and voice playback elicited responses from 1714 (36.09%) of these. Combining the 2019-2021 census results, the overall number of burrows counted is 28,884, 55.80% above the total the previous census (18,539). Likewise, the total number of AOBs has increased by 52.95%, from 17,276 in the 2014-2016 census to 26,423 in the current census. The island’s population is now estimated at 26,423 pairs. 7 ACKNOWLEDGEMENTS Thanks are due to Ollie King and Joel Tragen, Patrick Davies, Kevin Clements and Steph Harris for helping with the fieldwork, and to Steve and Emma Stansfield and Patrick Davies for commenting on an early draft of this paper. 8 REFERENCES Booker, H., Price, D., Slader, P., Frayling, T., Williams, T., & Bolton, M. 2019. Seabird recovery on Lundy British Birds 112: 217-230. Brooke, M. 2013. The Manx Shearwater. T&AD Poyser, London. Dykes, B. & Stansfield. S. 2019. Breeding birds: a summary of the breeding season on Bardsey and Ynysoedd Gwylan in 2018. 2018 Bardsey’s Wildlife. Rep. Bardsey Bird Fld. Obs. 62:134-159. Hooper, L., Hewitt, J., & Stansfield, S. 2020. Manx Shearwater Population Census 2019-2022 year 1. 2019 Bardsey’s Wildlife. Rep. Bardsey Bird Fld. Obs. 63: 178-187. Murray, S., Shewry, M.C., Mudge, G.P. & Spray, S. 2003. A survey of Manx Shearwaters Puffinus puffinus on Rum, Inner Hebrides in 2001. Atlantic seabirds, 5: 89-100. Perkins, A.J., Douse, A., Morgan, G., Cooper, A. & Bolton, M. 2017. Using dual-sex calls improves the playback census method for a nocturnal burrow-nesting seabird, the Manx Shearwater Puffinus puffinus. Bird Study, 64:146-158. Perrins, C.M., Wood, M.J., Garroway, C.J., Boyle, D., Oakes, N., Revera, R., Collins, P. & Taylor, C. 2012. A whole-island census of the Manx Shearwaters Puffinus puffinus breeding on Skomer Island in 2011. Seabird, 25:1-13. Prettyman, S. Manx Shearwater Population Census 2019-2022 year 1. 2020 Bardsey’s Wildlife. Rep. Bardsey Bird Fld. Obs. 64: 182-191 Stansfield, S., & Carter, M. 2017. Manx Shearwater studies: Manx Shearwater 2014-2016 population census. 2016 Bardsey’s Wildlife. Rep. Bardsey Bird Fld. Obs. 60: 152-158. Walsh, P.M., Halley, D.J., Harris, M.P., Del Nevo, A., Sim, I.M.W. & Tasker, M.L. 1995. Seabird monitoring handbook for Britain and Ireland: a compilation of methods for survey and monitoring of breeding seabirds. JNCC/RSPB/ITE/Seabird Group.
8 0 BETTERIDGE REP. BARDSEY BIRD FLD OBS. CHOUGH A summary of the 2021 breeding season Steven Stansfield CHOUGHS A summary of the 2022 breeding season Ed Betteridge Chough © Steven Stansfield Chough © Steven Stansfield
8 1 MANX SHEARWATER CENSUS 6 5 : 1 8 8 - 2 0 1
204 BETTERIDGE REP. BARDSEY BIRD FLD OBS. 1 INTRODUCTION Choughs Pyrrhocorax pyrrhocorax breed across much of central Asia, southern and eastern Europe and Morocco, with small outlying populations in the Canary Islands, Ethiopia and Sudan. Historically, Choughs bred around much of the UK’s coastline and some parts of inland Scotland. However, due to persecution and changes in livestock management, the UK population underwent a steep decline and range contraction during the late 1800s, leaving the only remaining breeding birds in their current strongholds (Bullock et al., 1983). In the early 20th century, Chough populations in England and Scotland continued their downward trajectory, whilst those in Wales and on the Isle of Man showed some signs of recovery. The most recent national census of Choughs in the UK and the Isle of Man took place in 2014, and estimated the population to be 394 breeding pairs, with the majority found in Wales (59%) and the Isle of Man (30%),(Hayhow et al., 2018). Overall, numbers of Choughs in the UK and the Isle of Man have fallen only very slightly between this survey and the previous one in 2002 which estimated 399 pairs. However, these population trends exhibit some geographical variation, with overall increases in Wales, the Isle of Man, and the Cornwall and South Wales population, contrasting with a 25% decline in Scotland, and smaller declines in parts of north and mid-Wales. Choughs are comprehensively protected in the UK and Europe since they are listed under Schedule 1 of the Wildlife and Countryside Act 1981, as well as Annex 1 of the EC Conservation of Wild Birds Directive 1979. The Bardsey population is further protected as they are a feature of the Aberdaron Coast and Bardsey Island (Glannau Aberdaron ac Ynys Enlli) Special Protection Area (SPA) and Bardsey Island Site of Special Scientific Interest (SSSI), in addition to being listed in Gwynedd’s Local Biodiversity Action Plan. STATUS AND LEGAL PROTECTION • Listed as a protected species under Annex I of the EC Conservation of Wild Birds Directive 1979 (2009/147/EC) • Protected under Schedule 1 of the Wildlife and Countryside Act 1981 • A designated feature of the Bardsey Island/Ynys Enlli SSSI • Feature of the Aberdaron Coast and Bardsey Island/Glannau Aberdaron ac Ynys Enlli SPA • Listed in the Gwynedd Biodiversity Action Plan • Feature of the Bardsey Island National Nature Reserve
205 CHOUGHS 6 6 : 20 2 - 2 1 7 Fig. 1 Bardsey Chough breeding population 1953-2022 The Chough population on Bardsey has increased substantially since the Observatory began monitoring them, with numbers gradually increasing from one pair in 1953. Prior to the start of this century an average of four pairs nested each year, but since 2001 this has increased to around seven pairs annually. Seven pairs bred on Bardsey in both 2019 and 2020. This fell to six pairs in 2021. In 2022 six pairs again nested 30.43% greater than the mean number of pairs for 1953-2022 (4.60 ±s.d.2.24). Average number of breeding pairs (±s.d.) Average number of chicks fledged (±s.d.) Average productivity: chicks/pair (±s.e.) 1953-2022 4.60 ±2.24 11.46 ±5.95 2.64 ±0.13 1953-1970 2.11 ±0.96 6.24 ±3.03 3.27 ±0.29 1973-2000 4.29 ±1.24 10.89 ±5.03 2.48 ±0.18 2001-2010 6.00 ±0.67 16.90 ±6.30 2.79 ±0.28 2013-2022 7.70 ± 1.16 15.90 ±4.23 2.07 ±0.15 Table 1. Average number of breeding pairs, average number of chicks fledged and average productivity 1953-2022 Fig. 2. Number of pairs, productivity and young 1998-2022 0 1 2 3 4 5 6 7 8 9 10 1953 1955 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 2017 2019 2021 Year Pairs Mean Number of pairs 4.60 ±s.d.2.24 0 5 10 15 20 25 30 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 4.50 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 Number of Pairs and Young Year Pairs Productivity Young Productivity
206 BETTERIDGE REP. BARDSEY BIRD FLD OBS. 2 AIMS As Choughs are a designated feature of the Bardsey Island SSSI and NNR, the Welsh government has a statutory obligation to monitor the population. This is done through the countryside agency, Natural Resources Wales (NRW), who in turn contract BBFO to undertake the work through Section 16 of the Wildlife and Countryside Act Management Agreement. 3 METHODS Choughs were monitored throughout the breeding season. Nests were located during the early part of the season and regular visits were made; each pair was observed for up to two hours per visit to confirm breeding and other activity. Once they reached a suitable size, chicks in all accessible nests were fitted with a single metal ring, and three plastic colour rings in a unique combination that allows them to be individually identified in the field, post-fledging. Once the chicks fledged, they were monitored until they left the island. All nest visits and ringing were conducted under the appropriate licences from NRW and the British Trust for Ornithology (BTO). 4 RESULTS Fourteen traditional nest sites were checked and subsequently monitored during the 2022 breeding season, with six pairs attempting to breed. This was the same as 2021, however down on the seven pairs in 2020. Five of the six pairs were confirmed to have successfully fledged young, with a total of 15 chicks fledging (1 x 1 chick, 2 x 3 chicks and 2 x 4 chicks). The number of fledged chicks in 2022 is 5.66% lower than the ten-year mean (15.90±s.d.4.23), and 25.00% higher than in 2021. Productivity was 25.00% higher than in 2021. Year 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 № of pairs 9 8 9 8 9 8 7 7 6 6 № of young 13 24 18 14 22 15 11 15 12 15 Productivity 1.44 3.00 2.00 1.75 2.44 1.88 1.57 2.14 2.00 2.50 Table 2 Number of pairs, number of young and productivity 2013 -2022 Fig. 3 Male Chough near the Black Anvil nest site © Ed Betteridge
207 CHOUGHS 6 6 : 20 2 - 2 1 7 4.1 NESTING ACTIVITY OF CHOUGHS ON BARDSEY IN 2022 1 NORTH WEST CORNER – no activity Date Start Finish Nesting activity 29/4/2022 14:35 16:35 No activity 18/05/2022 09:30 11:30 No activity 2 OGOF MORLAS – no activity Date Start Finish Nesting activity 15/04/2022 11:10 12:30 No activity 05/05/2022 15:30 16:00 No activity 07/05/2022 15:00 15:15 No activity 14/05/2022 17:10 17:25 Nest site visited; no sign of activity 3 BLACK ANVIL – three chicks fledged Bird Ring number Right combination Left combination Female Un-ringed Male ASH/METAL ORANGE/ ORANGE Chick 1 EX04835 ASH(1A)/METAL MUD/ MUD Chick 2 EX04836 ASH(1C)/METAL MUD/WHITE Chick 3 EX04837 ASH(1E)/METAL MUD/YELLOW Chick 4 EX04838 ASH(1F)/METAL MUD/ORANGE Date Start Finish Nesting activity 15/04/2022 11:10 12:30 Pair passed straight west at 11:20, presumably the same returned at 11:50 and flew to nest site. Both came out and were feeding above nest site and rings were read. Female went into nest site and did not leave. Male flew south where it approached other (Zawn?) pair; was seen on and off around the other pair/feeding (12:00-12:15) 05/05/2022 15:20 16:00 Bird flushed from nest site. Male feeding high above (15:59) 07/05/2022 15:00 15:15 Bird flying above nest site 09/05/2022 15:00 15:15 Pair dropped in 19/05/2022 13:45 14:00 Pair dropped in together (13:52) then single bird flew south (13:53) after being flushed by Peregrine 29/05/2022 11:45 12:00 Nest site visited, four large chicks present (11:53) 31/05/2022 15:45 16:15 Nest site visited and four chicks ringed 22/06/2022 18:00 18:10 Pair seen flying above with two chicks 24/06/2022 14:00 14:15 Pair seen flying above with two chicks 11/07/2022 10:00 10:10 Chicks 1A, 1E and 1F seen together on the West Coast past Solfach
208 BETTERIDGE REP. BARDSEY BIRD FLD OBS. 4 TRWYN PINC – no activity Date Start Finish Nesting activity 15/04/2022 11:10 12:30 No activity 05/05/2022 16:15 17:15 No activity 07/05/2022 15:15 17:15 No activity 19/05/2022 13:45 15:45 No activity 5 CARREG LLWYDION – no activity Date Start Finish Nesting activity 15/04/2022 11:10 12:30 No activity 05/05/2022 16:15 17:15 No activity 07/05/2022 15:15 17:15 No activity 19/05/2022 13:45 15:45 No activity 6 BAE FELEN – no activity Date Start Finish Nesting activity 15/04/2022 12:00 12:20 Pair seen feeding high above Bae Felen (1 un-ringed, 1 ?) before both flying down and straight in the Zawn site (12:18) 05/05/2022 16:20 17:15 Nest site visited, no sign of any activity 07/05/2022 15:15 17:15 No activity 14/05/2022 14:50 16:50 No activity 29/05/2022 12:15 12:30 No activity, nest site visited and nothing found 7 THE ZAWN – no activity Date Start Finish Nesting activity 15/04/2022 12:00 12:20 Pair seen feeding high above Bae Felen (1 un-ringed, 1?) before both flying down and straight in the Zawn site (12:18) 05/05/2022 16:20 17:15 Nest site visited, no sign of any activity 09/05/2022 09:30 10:00 Pair went in at (9:35) and pair in again (9:55) 14/05/2022 14:50 16:50 No activity
209 CHOUGHS 6 6 : 20 2 - 2 1 7 8 SEAL CAVE – three chicks fledged Date Start Finish Nesting activity 26/04/2022 15:45 16:45 Female sat above nest site (15:47-16:10), then flew in, two flew out then mobbed another pair to the north (16:12) 08/05/2022 14:30 16:15 Female flushed from nest (14:25), nest site visited, two chicks and two eggs present (14:32). Both birds seen above nest site with both visiting the nest (14:51-15:01) after leaving. Male then left female in nest before returning above nest 15:36 09/05/2022 10:30 10:35 Pair dropped in 14/05/2022 14:35 16:50 Bird flew out of nest site (14:45), bird in (15:31), pair flew out and fed for c.2mins above the Zawn before flying west (15:43), bird visited again (16:37) 24/05/2022 15:00 16:30 Nest visited and four chicks ringed. Pair remained above nest site and revisited within five minutes of leaving 21/06/2022 15:00 16:30 Three chicks above nest with both parents plus a dead unringed chick in nest site – meaning there were five chicks hatched. 9 OGOF BRAICH Y FWYAF – no activity Date Start Finish Nesting activity 26/04/2022 15:00 17:00 No activity 08/05/2022 14:50 16:50 No activity 10 TORNADO LEDGE – no activity Date Start Finish Nesting activity 26/04/2022 15:00 17:00 No activity 08/05/2022 14:50 16:50 No activity Bird Ring number Right combination Left combination Female Un-ringed Male Unknown METAL WHITE/WHITE Chick 1 EX04831 GREEN/RED ASH/METAL Chick 2 EX04832 GREEN /LIME ASH/METAL Chick 3 EX04833 GREEN /GREEN ASH/METAL Chick 4 EX04834 GREEN /BLUE ASH/METAL
210 BETTERIDGE REP. BARDSEY BIRD FLD OBS. 11 OGOF BARCUT – four chicks fledged Date Start Finish Nesting activity 03/04/2022 16:30 17:45 No activity 13/04/2022 14:25 15:45 Pair arrived, one individual went straight into nest then another in and straight back out where it fed and preened above nest site for c.5 mins (un-ringed) 26/04/2022 16:45 17:00 Un-ringed bird above nest (15:15) calling. Male called female off nest (15:23) and both sat above the nest site until 15:26 02/05/2022 14:00 16:00 Un-ringed feeding high above nest site (14:33). Un-ringed again above the nest site (15:09). Bird flew into nest hole (15:10), pair past Ogof Barcut (15:13). Bird flew into nest site (15:29), pair above nest site (16:00) 14/05/2022 14:15 14:30 Nest site visited and no sign of any activity 15/05/2022 14:00 14:55 Pair seen flying above before dropping in, birds observed from a distance and were seen to enter nest hole. Nest site visited and found to have at least three chicks (14:20). Pair together above Pen Cristin (14:51) 25/05/2022 17:55 18:10 At least three chicks still present in nest (18:00) however, out of reach 29/06/2022 15:00 15:30 Two adults and four chicks feeding above the Zawn, presumed to be this pair as neither adults or chicks were ringed Fig. 4 Chough on Solfach in March © Ed Betteridge Bird Ring number Right combination Left combination Female Un-ringed Male Un-ringed
211 CHOUGHS 6 6 : 20 2 - 2 1 7 12 PEN CRISTIN – one chick thought to have fledged Date Start Finish Nesting activity 03/04/2022 16:30 17:45 No activity 13/04/2022 14:25 15:45 One arrived at 15:15 and went straight in and was shortly followed by another bird c.1 min later that landed out of sight then carried on south 26/04/2022 13:50 15:30 Un-ringed was above nest site (14:12) then flew south. Un-ringed then returned to nest site (14:25) for c.2mins 02/05/2022 14:00 16:00 Pair in flight above nest site (14:06), male then alone to the south (14:09) then both south (14:10). Male back above nest (14:36), female into nest (14:39) then both south (14:41) One in (14:50), male flying above then feeding to the south (14:57). Pair flew south (15:06). Male back above nest (15:57) 14/05/2022 14:15 14:30 Bird seen visiting nest site 15/05/2022 14:00 14:55 Bird seen visiting nest site (13:34), then feeding above (13:38- 13:50), pair above nest fighting the Ogof Barcut pair (14:51) 23/05/2022 14:15 14:20 Pair in together (14:16) 23/06/2022 19:00 19:10 Pair with one chick above Pen Cristin thought to be this family 13 OGOF DIBAN – failed at chick stage Date Start Finish Nesting activity 22/04/2022 17:44 18:00 Male called female off nest and both flew off south (17:49) 10/05/2022 09:40 09:50 Pair seen feeding on South End just north of nest site 12/05/2022 14:20 14:45 Pair seen together just east of nest site. Nest visited and four chicks present (14:27). Birds returned and visited chicks almost immediately (14:31) 27/05/2022 19:45 20:00 Nest visited, two chicks dead just outside nest and nest empty; presumed killed by recent storms. Pair still around nest area Bird Ring number Right combination Left combination Female Un-ringed Male Unknown YELLOW/BLACK METAL Bird Ring number Right combination Left combination Female ORANGE/# “0F” LIME/METAL Male Unknown METAL GREEN/GREEN
212 BETTERIDGE REP. BARDSEY BIRD FLD OBS. 14 OGOF TRWYN-YR-HWCH BACH – four chicks fledged Date Start Finish Nesting activity 09/04/2022 08:15 08:25 Male sat above nest, called out female and displayed 14/04/2022 17:25 17:30 Pair feeding together above nest site 15/04/2022 09:00 09:05 Male feeding alone above nest site 29/04/2022 14:25 14:30 Male feeding above nest site, flew down and called female off nest 23/05/2022 13:20 13:40 Pair circled above then were feeding to the east before dropping into nest site (13:37) 14/06/2022 09:50 10:00 Male and female and four young feeding on cliffs above nest 22/06/2022 09:30 10:00 Four young and two adults on Solfach 18/06/2022 09:30 09:30 Female with four young 5 DISCUSSION Chough numbers on Bardsey have fluctuated dramatically since monitoring began in 1953. However, the trend clearly shows an increase in the breeding population, with a minimum of nine pairs attempting to breed in three of the last ten years. The population trend suggests that Choughs are responding positively to the management of the island, where grazing by both sheep and cattle is creating an abundance of short sward semi-natural vegetation. The number of Chough pairs breeding on Bardsey this year was the same as last year and was 22.08% lower than the ten-year average (7.70±s.d.1.16). Breeding success was higher than last year, with three more chicks fledging from six pairs. Of the six active pairs, only one failed to rear young, failing at the chick-rearing stage. The nest was visited and found to be clearly damaged by recent storms. The overall productivity in 2022 was 2.50, 25% higher than the previous year and 20.77% higher than the ten-year mean of 2.07±s.e.0.15. Choughs on Bardsey will be affected by wider environmental variables such as changes in climate or population fluctuations elsewhere. However, on a local level, specific management on the island is likely to have a significant impact, particularly on the extent of suitable feeding habitat. The fact that the population is stable goes some way to indicate that the management of the island for Choughs is successful. By grazing both sheep and cattle, the island maintains an appropriate amount of short grassland areas as favoured feeding areas for Choughs. Bird Ring number Right combination Left combination Female GREEN/ #“3T”, GREEN/METAL Male ASH/METAL BLUE
213 CHOUGHS 6 6 : 20 2 - 2 1 7 5.1 MANAGEMENT STATEMENTS AND SPECIES TARGETS Although now outdated, the latest management statement for Choughs on Bardsey (2010-2015) from the 2010 Conservation Management Plan Supplement (Moralee 2010) states: The species targets as listed in the 2010 Management Plan Supplement are: In the Guide for land managers: Summary of Island Management Plan 2002-2006, Wilkinson (2004) gives a ‘Vision’ for the Feature: Further to the Wilkinson plan (2004), Moralee (2010) refined the grazing prescriptions for many of the areas which are managed for Chough feeding (amongst other things). Most areas within the SPA and SAC have very similar, if not identical, sward height objectives within the plan. ‘VISION’ FOR THE FEATURE Size of breeding population is stable or increasing as far as availability of nest sites will allow (min 1% UK population) and non-breeding individuals are present and utilising the island for feeding and social interaction To contribute to the maintenance of the internationally important population (1% or more of the Great Britain population) of breeding and non-breeding season Chough within the Glannau Aberdaron and Ynys Enlli SPA • The breeding population of Chough is at least four pairs • The wintering population of Chough is at least ten individuals • Sufficient suitable habitat is present to support the populations • Breeding population is stable or increasing • Productivity is stable • Breeding and non-breeding birds use Ynys Enlli for feeding throughout the year • Chough feeding habitats are themselves in a favourable conservation status and that the specified and operational limits and grazing prescriptions for these habitats incorporate Chough feeding requirements (i.e. sward height and bare ground) • Disturbance of breeding and feeding Chough is minimal • The factors affecting the feature are under control
214 BETTERIDGE REP. BARDSEY BIRD FLD OBS. 5.2 BREEDING AND PRODUCTIVITY The Management Plan for Ynys Enlli (Wilkinson 2004) stated that the acceptable minimum limit for nesting pairs of Choughs is five pairs in three years of any five-year period. The number of pairs has now been five or more for the last 20 years and should therefore be seen as being in a favourable condition. Productivity in 2022 was 2.50 chicks per pair. This is 25% higher than the 2021 productivity rate of 2.00 and exactly the acceptable minimum of 2.50 chicks per pair set in the Management Plan. This makes 2022 the highest year for productivity since 2014. The supplement to the Management Plan (Moralee 2010) targets ‘stable productivity’, but this target has not been met since 2014 when productivity was 3.00. The mean productivity over the last decade is 2.07 (±s.e.0.15) with fluctuations as low as 1.44 in 2013 and reaching a peak of 3.00 in 2014; the 2022 productivity rate of 2.50 was 22.08% lower than the ten-year mean and also 5.30% lower than the long-term 1953-2022 mean (2.64 ±s.e.0.13). Wilkinson (2004) stated that one of the indicators of the ‘health of the feature’ would be the production of >2.5 chicks per pair each year. However, Fig. 6 shows that a productivity figure of >2.5 chicks per pair has been achieved in only one of the past ten years. Based on this alone, the feature would not be in a favourable condition, productivity, however, is calculated by dividing the number of young fledged by the total number of pairs breeding or attempting to breed, and does not take into account the age structure or experience of the birds within that population. A larger population with a high proportion of young, inexperienced birds, as is currently the case on the island, will inevitably lead to lower productivity than from a smaller population made up of experienced pairs. Therefore, the productivity of Bardsey’s Choughs is expected to increase over the coming years as the current immature birds gain experience. The fact that this year's productivity hit the target figure of 2.5 is possible evidence of this trend. Fig. 5 Choughs near Solfach in October © Ed Betteridge
215 CHOUGHS 6 6 : 20 2 - 2 1 7 Fig. 6 Productivity 1953-2022 Fig. 7 Productivity 2013-2022 Over the past decade 159 young have been produced, with the lowest total being 11 in 2019 and the highest 24 in 2014 which was the year that saw the highest productivity of the last decade. The ten-year mean is 2.07, 17.20% below the proposed target productivity of 2.5 chicks per pair. Fig. 8 Number of young produced per annum 2013-2022 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 1953 1955 1957 1959 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 2017 2019 2021 Year Productivity Mean Productivity 2.64 ±s.e.0.13 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 Year Productivity Mean Productivity 2.07 ±s.e.0.15 0 5 10 15 20 25 30 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 Year Young Mean Number of Young 15.90 ±s.d.4.23
216 BETTERIDGE REP. BARDSEY BIRD FLD OBS. 5.3 WINTERING AND NON-BREEDING CHOUGHS Any flocks of significant size had departed the island by March when Observatory staff returned to the island. Pairs had started to form and some were nest building. There were few notable arrivals of mainland breeding birds until 16 October when a flock of 40 was seen around the Narrows and the South End. Sightings of colour-ringed individuals proved that many of these mainland breeding birds remained on the island until the end of the season; however, counts never exceeded 20. Fig. 9 Maximum daily counts for Choughs on Bardsey in 2022 Fig. 10 Chough near Solfach in October © Steven Stansfield 0 5 10 15 20 25 30 35 40 45 J F M A M J J A S O N D Daily count of birds
217 CHOUGHS 6 6 : 20 2 - 2 1 7 6 SUMMARY 2022 was the first year since 2014 where the target productivity rate of 2.50 was met. During 2022, six pairs attempted to breed, 22.08% below the ten-year mean (7.70±s.d.1.16), and of these, five successfully fledged young. The other pair failed during the chick-rearing stage when the nest was washed out by the sea during storms. The resulting 2.50 chicks per pair is 20.77% greater than the ten-year mean (2.07±s.e.0.15). The number of young fledged (15) is 5.66% below the ten-year mean (15.90±s.d.4.23). Therefore, although the acceptable limits set out for the management of the NNR, SPA and SAC for productivity were met, the reduction in breeding pairs since 2017 resulted in a lower than average number of chicks over the past decade. However, looking long term, the population of six pairs is 30.35% greater than the long-term (1953-2022) mean (4.6±s.d.2.24), with the productivity being 5.30% lower than the long-term mean (2.64 ±s.e.0.13). 7 REFERENCES Baillie, S.R. 1990. Integrated population monitoring of breeding birds in Britain and Ireland. Ibis, 132: 151- 166. Bullock, I., Drewett, D. & Mickleburg, S. 1983. The Chough in Britain and Ireland. British Birds, 76: 377–401. Hayhow, D.B., Johnstone, I., Thorpe, R., Moore, A. and Finney, S. 2007. Breeding status of Choughs Pyrrhocorax pyrrhocorax in the UK and Isle of Man in 2002. Bird Study, 54: 23-34. Hayhow, B.D et al. 2018. Status of breeding Chough Pyrrhocorax pyrrhocorax in the UK and Isle of Man 2014. Bird Study 65: 458-470. Hewitt, K. & Wilkinson, H. 2003. Ynys Enlli NNR Conservation Management Plan. Countryside Council for Wales. Loxton, R.G. and Jones, P.H. 1995. The breeding birds of Bardsey, Skomer, Skokholm and the Calf of Man. Part1: Introduction and species accounts. Rep. Bardsey Bird Fld Obs. 38: 84-159. Loxton, R.G., Kittle, T. and Jones, P.H. 1999. Atlas of recoveries of birds ringed by Bardsey Bird and Field Observatory 1953-1996. BBFO, Bethesda, Gwynedd. McCanch, N. 2000. The relationship between Chough Pyrrhocorax pyrrhocorax breeding populations and grazing pressure on the Calf of Man. Bird Study, 47: 295-303. Moralee, A. 2010. Ynys Enlli Nature Conservation Management Plan drafted on behalf of the Bardsey Island Trust by RSPB. Unpublished. Natural Resources Wales. Perfect, E. 2018. Chough breeding studies update. Rep. Bardsey Bird Fld. Obs. 61: 208-219. Reid, J. M., Bignal, E. M., Bignal, S., McCracken, D. I. and Monaghan, P. 2003. Environmental variability, life-history covariation and cohort effects in the Red-billed Chough Pyrrhocorax pyrrhocorax. Journal of Animal Ecology 72: 36-46 Reid, J. M., Bignal, E. M., Bignal, S., Bogdanova, M. I., Monaghan, P. and McCracken, D. I. 2011. Diagnosing the timing of demographic bottlenecks: sub-adult survival in red-billed choughs. Journal of Applied Ecology 48: 797-805 Roberts, P. 1983. Feeding habitats of Choughs on Bardsey Island. Bird Study, 30: 67-73. Roberts, P. 1985. The Choughs of Bardsey. British Birds 78: 217-232. Stansfield, S.D. 1999. Chough breeding success and choice of feeding habitat on Ynys Enlli in 1998. Rep Bardsey Bird Fld Obs. 42: 59-64 Stansfield, S.D. 2003. Breeding success of the Chough Pyrrhocorax pyrrhocorax on Ynys Enlli in 2002. Unpublished Report to NRW for Grant-aided work in 2002. Stansfield, S.D. & Carter, M. 2017. Chough breeding studies update. Rep. Bardsey Bird Fld. Obs. 60: 170- 180. Wilkinson, H. 2004. Guide for Land Managers, Summary of island management plan 2002-2006 Volume 1: background & designated features. Countryside Council for Wales.
218 BETTERIDGE REP. BARDSEY BIRD FLD OBS. The purpose of ringing birds is to collect data to monitor survival rates and movements, amongst other things. This provides a fundamental contribution to conservation as it helps scientists to understand the causes of changes in population sizes over time, and therefore how to prevent and reverse declines. The data collected from ringing can be analysed and used to inform decision making by governments, conservation bodies and economic developers. All naturally-occurring wild birds in the UK are protected from persecution under the Wildlife and Countryside Act (1981). It is illegal to kill, injure or ‘take’ any wild bird, or to take or damage the nest of any wild bird whilst in use or being built. The eggs of all wild birds are also protected. It is an offence to have in your possession any live wild birds. As a result, all bird ringing in the UK requires a special licence, and follows specific regulations. The British and Irish Ringing Scheme is run and administered by the British Trust for Ornithology (BTO) www.bto.org The BTO issues ringing licences on behalf of the UK and Irish Governments. A licence to ring birds is issued only after initial approval, followed by a lengthy training process by an authorised instructor. Qualified ringers catch birds using mist nets, Heligoland traps, spring traps and other methods; a small, uniquely-numbered metal ring is then carefully placed around the bird’s leg providing a reliable and harmless method of identifying the birds as individuals. Licensed ringing at Bardsey Bird Observatory operates to a high standard and ringing training is also available. In line with BTO regulations, all of the ringing data that Bardsey Bird Observatory has collected since 1953 has been submitted to the BTO and has been incorporated into their national database, as well as being held in our own databases. The BTO is one of the world’s leading impartial scientific research organisations specialising in knowledge about wild birds. The BTO is interested in changes to populations in relation to their ecology and the habitats on which they depend. Their information base includes long-term datasets, such as ours, that have been in place for at least 50 years. BIRD RINGING Birds ringed on Bardsey in 2022 Ed Betteridge Red-flanked Bluetail being ringed © Emma Stansfield
6 6 : 2 1 8 - 2 3 7 219
220 BETTERIDGE REP. BARDSEY BIRD FLD OBS. 1 INTRODUCTION Each year birds migrate along their flyways all over the world in spring and autumn; many, as can be seen in the systematic list earlier in this report, are endangered. One of the ways we can understand more about them is to collect scientific data to support conservation; ringing forms part of the important research necessary to help protect species that are declining. Ornithologists around the world have been ringing for over 100 years and much of our current knowledge about migration and populations has come from ringing birds. Bardsey Bird Observatory started ringing when it was established in 1953 and has an ongoing programme of ringing. Up to the end of 2022 there have been 307,401 birds of 196 species ringed on the island. 2 METHODS Birds are trapped by licensed ringers in a variety of ways, such as in mist nets, Helgoland traps, spring traps, by whoosh-netting, dazzling and a number of other methods. A small metal ring is then placed on the bird’s leg using specialised pliers and rings; data is recorded about each individual bird. A summary of the ringing that was undertaken during the 2022 season is presented below, broken down monthly from mid-March, when ringing began, to the start of November, followed by a table showing the totals of each species ringed during the year. Pallas’s Warbler © Steven Stansfield
221 BIRD RINGING 6 6 : 2 1 8 - 2 3 7 3 RESULTS A total of 4243 birds were ringed in 2022, 4.89% lower than the 1953-2022 mean (4461.07±s.d.1963.39). Full-grown birds made up 3119 and the total number of pulli ringed in 2022 was 1124. Manx Shearwater was once again the most numerous species to be ringed in 2022: a total of 1380 was ringed, comprising 1234 full-grown and 146 pulli. Unusual species this year included the second Red-Flanked Bluetail, tenth Marsh Warbler, 13th Tree Sparrow, 18th Pallas’s Warbler, 19th Barred Warbler and 22nd Golden Oriole for the island. Alongside these, other scarce species caught included two Red-breasted Flycatchers and a Yellow-browed Warbler. Staff and volunteers made multiple trips around the East Side of the island to ring seabirds. Three visits were also made to Ynys Gwylan Fawr and for the first time in 20 years Observatory staff visited Ynys Gwylan Bach on a single occasion. As a result, this year saw the highest annual Razorbill total for 12 years, Guillemot total for 18 years, Puffin total for 22 years and Shag total for an astonishing 35 years! This year again saw the ongoing colour-ringing of gulls, Shags, Rock Pipits, Whimbrels and Choughs. Most notable of these was the colour-ringing of 93 Herring Gulls, 14 Lesser Black-backed Gulls and 32 Great Black-backed Gulls; in total 139 gulls were fitted with colour rings, the highest ever annual total. Shags also hit a new high with 112 being colour-ringed; with an additional 127 ringed with only a metal ring. The overall total of 251 birds that were colour-ringed was the highest since 1987. Avian Influenza outbreaks in Wales meant that in mid-August all seabird ringing was prohibited; this resulted in a reduction in Storm Petrel mist-netting and Manx Shearwater pullus ringing. For all other bird species, new measures were put in place to reduce the spread by sanitising all equipment between birds and not visiting the East Side seabird colonies. After a good year for House Martins last year, this year saw a new record being set yet again, with 242 being caught, all were juveniles bar one adult. The total of 242 was 90.55% higher than the 1953-2021 total (127). Dazzling (or lamping) over multiple nights during the year helped to catch a range of unusual species including Bar-tailed Godwit, Water Rail, Long-eared Owl, Snipe and Purple Sandpiper. Dazzling also resulted in the capture of five Whimbrels which were fitted with colour rings. Once again, the portable Heligoland trap was used on Solfach, which resulted in 26 Rock Pipits and a single Meadow Pipit being ringed. Of the 26 Rock Pipits 24 were colour-ringed. 3.1 MONTHLY SUMMARIES Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total Number Ringed 0 0 77 456 269 1307 1065 539 198 331 1 0 4243 Number of Species 0 0 11 27 30 33 21 29 27 33 1 0 74 MARCH Mist-netting at Cristin started on 24th. Migrants were already passing through the island with 18 Goldcrests, nine Willow Warblers, 28 Chiffchaffs and ten Blackcaps, only one of which was a female, being caught. These totals were slightly down on previous years which may have been due to a slight delay in commencement of ringing. These commoner migrants were accompanied by a Firecrest, a Great Spotted Woodpecker and two Blue Tits. These migrants also attracted the attention of a female
222 BETTERIDGE REP. BARDSEY BIRD FLD OBS. Sparrowhawk which was caught at Cristin. Only 11 species were ringed this month compared to 17 in 2021 and 24 in 2020. APRIL The first full month of ringing resulted in a total of 27 species being trapped. Spring warbler passage on Bardsey peaks in April as was evident with 70 Willow Warblers, 173 Blackcaps and 51 Chiffchaffs. Chiffchaffs and Willow Warblers were both down on last year by 40.70% and 70.09% respectively. Other warblers caught included two Reed Warblers, a Garden Warbler, 19 Sedge Warblers and a Whitethroat. Finches moved through throughout the month with 29 Goldfinches, three Chaffinches, two Linnets, a Lesser Redpoll and a Bullfinch. Other birds caught at Cristin included nine Goldcrests and a Blue Tit. Dazzling produced three Whimbrels, two Purple Sandpipers and a Dunlin. The portable Heligoland was tried on one occasion this month and successfully caught a single Rock Pipit. The first Manx Shearwaters of the year were trapped during the month, with a modest 66 Manx Shearwaters being ringed. The month ended with an early Spotted Flycatcher caught at Cristin. MAY This month saw 269 birds of 30 species ringed. Phylloscopus warblers caught included 16 Willow Warblers and 12 Chiffchaffs plus a Siberian Chiffchaff. The only Lesser Whitethroat to be caught this year was trapped in the Withies; feathers were taken, and DNA analysis revealed this bird to be a Siberian Lesser Whitethroat (Curruca curruca blythi). Other warblers trapped included a Reed Warbler, 13 Sedge Warblers, 11 Whitethroats and 23 Blackcaps. Finches were in low numbers with only two Siskins and ten Goldfinches trapped. A single Swallow and Goldcrest made up the best of the rest. Three pullus Stonechats were ringed along the Green Lane and became the first pullus Stonechats since 1999. Trips around the East Side to monitor seabirds resulted in the start of seabird ringing; this included an adult Kittiwake, three adult and one pullus Puffins, four adult and one pullus Guillemots, 16 adult and 14 pullus Razorbills, 23 pullus Shags and eight pullus Herring Gulls. As well as the seabirds, four Chough pulli were ringed from a single nest. Dazzling around the beaches produced four Purple Sandpipers, two Ringed Plovers, a Dunlin, a Whimbrel, an Oystercatcher and a ‘Greenland’ Wheatear. An additional 73 Manx Shearwaters were trapped this month. JUNE The ringing highlight of the month was a young male Golden Oriole caught at Cristin on 2 June; this was the 22nd Golden Oriole to be ringed on Bardsey. The only other unusual species caught this month was a Black Redstart in the Heligoland trap. Warblers continued to pass through the island with a Blackcap, two Whitethroats, a Sedge Warbler, three Chiffchaffs and three Willow Warblers, two of which were island-bred youngsters, caught. Alongside warblers, another Spotted Flycatcher was caught at Cristin. Light finch movement produced a Goldfinch and two each of Siskins and Linnets. June also saw the first emergence of juvenile birds with four Stonechats and eight Robins being ringed. Dazzling at night produced a Meadow Pipit and a Rock Pipit. June saw the majority of the seabird ringing, mainly around the East Side and on the Gwylan Islands. A good year for Razorbills saw a total of 26 adults and 170 pulli being ringed, the highest total for 12 years and 107.30% higher than the mean. Guillemots had an even better year: 25 adults and 84 pulli were ringed, the highest annual total since 2004.
223 BIRD RINGING 6 6 : 2 1 8 - 2 3 7 Trips to the Gwylan Islands resulted in a total of 30 adults and 30 pullus Puffins ringed with an additional seven adults and four pulli being ringed on Bardsey itself. This represented the highest number of Puffins ringed in a year since 2000. A good year for Shags saw 214 ringed this month, 109 on Bardsey and 105 on the Gwylans; of which 112 were also fitted with a colour ring. Trips to the Gwylan Islands also resulted in the only pullus Cormorants of the year being ringed, with five trapped. In total of 270 Herring Gull pulli were ringed, 233 on Bardsey and 37 on Ynys Gwylan Fawr, 93 being colourringed. An additional 31 Lesser Black-backed Gulls and 43 Great Black-backed Gulls were ringed in total, with all but five of the Great Black-backed Gulls being ringed on the Gwylans. A total of 13 Lesser Blackbacked Gulls and 32 Great Black-backed Gulls were also fitted with colour rings. Five adult Fulmars were ringed during June; these became the first to be ringed on Bardsey since 2014 and the highest annual total for 21 years. Along with these seabirds an additional 277 Manx Shearwaters and 24 Storm Petrels were ringed. Ringed Plovers again bred on the Narrows and three chicks were ringed on Solfach. The only other waders ringed this month were an adult and two pullus Oystercatchers. JULY The start of the month saw the last of the gulls to be ringed; this included 18 Herring and 11 Lesser Blackbacked, of which one Lesser Black-backed was also colour ringed. The last two Shags of the year were also ringed at the start of the month, this resulted in a total of 239 for the year which is the highest since 1987. July saw the majority of Manx Shearwater adults of the year ringed with 863 trapped, as well as the first 45 pullus Manx Shearwaters ringed. Mist netting at Bae y Rhigol for Storm Petrels resulted in 112 caught during the month. Golden Oriole © Emma Stansfield
224 BETTERIDGE REP. BARDSEY BIRD FLD OBS. Warblers started to migrate back south for winter with nine Willow Warblers caught this month, all of which were juveniles. Other warblers ringed this month were two juvenile Blackcaps, three juvenile Whitethroats and an adult Sedge Warbler. The first Song Thrush of the year was caught at Cristin. An additional eight juvenile Robins and two Stonechats were caught. The only finches to be caught were three Linnets. Dazzling produced a Wheatear and the first Magpie of the year. AUGUST August saw yet more Manx Shearwater pulli being ringed, totalling 111. Mist-netting at Bae y Rhigol produced another 22 Storm Petrels, all on 1st. Unfortunately, avian influenza was found in Wales midmonth and all seabird ringing had to stop. After success with House Martins last year which saw 89 being caught, bringing the total ringed on the island to 124, this year saw another attempt to catch them. This proved to be extremely successful with an astonishing 242 being caught, all bar one of which were juveniles. A total of 12 Swallows were also ringed, of which three were pulli. This month saw the first big movement of Willow Warblers with 80 being trapped alongside two Chiffchaffs, three Blackcaps, a Sedge Warbler, a Grasshopper Warbler and a Whitethroat. The first and only Redstart of the year was caught in the Heligoland trap. Other passerine highlights were two Spotted Flycatchers, seven Goldcrests, 18 Robins, six Stonechats, six Goldfinches and a Linnet. Unusual species caught included a Woodpigeon, a Magpie and a Sparrowhawk. Dazzling during the month produced an Oystercatcher, a Curlew, a Dunlin, a Ringed Plover and a Wheatear. The Ringed Plovers had a second brood, this time on Henllwyn, and a single chick was ringed. The month ended with a Marsh Warbler being trapped at Cristin, this was only the 10th to be ringed on the island. SEPTEMBER Goldcrests were the most numerous bird ringed this month with 63 trapped. Warblers were thin on the ground and totalled only 31 Willow Warblers, seven Chiffchaffs, seven Blackcaps, a Whitethroat, a Grasshopper Warbler, two Reed Warblers and a Garden Warbler. However, the warbler highlight was a Barred Warbler. After none were caught in the spring, the first four Pied Flycatchers were trapped at Cristin along with two Spotted Flycatchers. A total of 31 Robins ringed during the month was notable along with a Sparrowhawk, two Swallows and a Goldfinch. A few of the fields around Tŷ Pellaf were again set aside for wildlife and planted with a range of seedbearing crops. This saw a large gathering of several hundred finches. Unfortunately, a mix of poor weather and birds preferring areas away from the nets meant that only a few birds were caught in these areas this year. These included five Meadow Pipits and four Linnets, however the highlight was a juvenile Tree Sparrow which was only the 12th to be ringed on Bardsey. A few nights of dazzling produced a good range of species with a Bar-tailed Godwit, a Snipe, two Ringed Plovers, a Dunlin, three Meadow Pipits and two Moorhens caught.
225 BIRD RINGING 6 6 : 2 1 8 - 2 3 7 OCTOBER The month saw a further 88 Goldcrests ringed, along with two Firecrests. Rather low numbers of warblers saw only six Chiffchaffs and 17 Blackcaps being caught. More unusual warblers included a Garden Warbler, a Reed Warbler, a Yellow-browed Warbler and a Pallas’s Warbler, the first of the latter to be ringed since 2017. Incredibly, this month saw two Red-breasted Flycatchers ringed; the first at Nant on 25th and the second from the Heligoland trap at Cristin on 27th. However, the ringing highlight of the month, and perhaps the year, was a Red-flanked Bluetail caught in Plas Withy on 29th; this is only the second to be ringed on Bardsey after the first in 2007. A notable increase in Blackbirds and Song Thrushes saw respectively 11 and four of each ringed. Along with these 11 Redwings were caught, the first of the year. Robins were still passing through the island with an additional 18 ringed during the month. Finch passage picked up, with an increase in numbers caught. This included 98 Chaffinches, two Goldfinches, eight Lesser Redpolls and two Siskins. Along with these the only Greenfinch and Brambling was caught at Cristin. The portable Heligoland trap was placed on Solfach and was successful in catching 25 Rock Pipits and a Meadow Pipit. The majority of Rock Pipits were also fitted with a white Darvic-ring to aid re-sightings. Dazzling on 15th produced the first Redshank of the year. The following night exceeded all expectations when two Long-eared Owls were trapped, both young females. A fine drake Mallard was caught on 22nd and was the only one to be caught this year. Dazzling on 25th produced two Water Rails, the first to be ringed in five years. Incredibly, another Long-eared Owl was trapped on 26th. Dazzling this month also produced a Snipe, eight Moorhens, two Magpies, two Meadow Pipits and a Rock Pipit. NOVEMBER A single Goldcrest trapped on 1st was the final bird to be ringed in 2022. Red-flanked Bluetail © Steven Stansfield
226 BETTERIDGE REP. BARDSEY BIRD FLD OBS. 3.2 TOTALS TABLE Table 1. Number of birds ringed in 2022, a comparison with the 2021 totals and with the 1953-2022 mean, number of birds ringed from 1953-2022, the annual maxima, and the 1953-2022 mean ∑ compares 2022 total with 2021 total, x̄ compares 2022 total with 1953-2022 mean, ↑ = Up on, = = Equal to, ↓ = Down on, FG = Full Grown Species 2022 Pullus 2022 FG 2022 Total ∑ x̄ 53-2022 Pullus 53-2022 FG 53-2022 Total Annual Maxima 53-2022 Mean Quail = ↓ 5 5 1 0.07 Shelduck = ↓ 2 8 10 3 0.15 Mallard 1 1 ↑ ↑ 28 18 46 6 0.68 Teal = ↓ 9 9 2 0.13 Nightjar = ↓ 3 3 1 0.04 Swift = ↓ 29 29 6 0.43 Cuckoo = ↓ 1 87 88 8 1.29 Rock Dove = ↓ 1 1 2 2 0.03 Stock Dove = ↓ 1 1 1 0.01 Woodpigeon 3 3 ↑ ↑ 44 140 184 12 2.71 Turtle Dove = ↓ 37 37 9 0.54 Collared Dove = ↓ 58 58 6 0.85 Water Rail 2 2 ↑ ↓ 223 223 17 3.29 Corncrake = ↓ 15 15 5 0.22 Sora = ↓ 1 1 1 0.01 Moorhen 10 10 ↑ ↑ 53 410 463 37 6.81 Little Grebe = ↓ 3 3 2 0.04 Oystercatcher 2 3 5 ↑ ↓ 707 168 875 54 12.87 Lapwing = ↓ 149 10 159 26 2.34 Golden Plover = ↓ 4 4 1 0.06 Grey Plover = ↓ 4 4 1 0.06 Ringed Plover 4 5 9 ↑ ↑ 31 195 226 16 3.32 Dotterel = ↓ 2 2 1 0.03 Whimbrel 5 5 ↑ ↑ 2 128 130 26 1.91 Curlew 1 1 ↑ ↓ 3 114 117 22 1.72 Bar-tailed Godwit 1 1 ↑ ↑ 45 45 6 0.66 Turnstone = ↓ 320 320 31 4.71 Knot = ↓ 76 76 18 1.12 Curlew Sandpiper = ↓ 6 6 3 0.09 Sanderling = ↓ 20 20 4 0.29 Dunlin 4 4 ↑ ↓ 600 600 45 8.82 Purple Sandpiper 6 6 ↑ ↑ 80 80 17 1.18 Baird's Sandpiper = ↓ 1 1 1 0.01 Little Stint = ↓ 8 8 1 0.12 Pectoral Sandpiper = ↓ 2 2 1 0.03 Woodcock = ↓ 58 58 12 0.85 Jack Snipe = ↓ 40 40 6 0.62 Snipe 2 2 ↑ ↑ 58 58 8 0.85 Grey Phalarope = ↓ 4 4 1 0.06 Common Sandpiper = ↓ 67 67 9 0.99 Spotted Sandpiper = ↓ 1 1 1 0.01 Redshank 1 1 ↑ ↓ 138 138 11 2.03 Greenshank = ↓ 3 3 1 0.04 Kittiwake 1 1 ↓ ↓ 1037 194 1231 144 18.10 Sabine's Gull = ↓ 2 2 1 0.03 Black-headed Gull = ↓ 1 1 1 0.01 Great Black-backed Gull 43 43 ↑ ↑ 1153 13 1166 88 17.15 Herring Gull 296 296 ↑ ↑ 10,668 130 10,798 768 158.79 Lesser Black-backed Gull 42 42 ↑ ↑ 2625 211 2836 237 41.71 Little Tern = ↓ 1 1 1 0.01 Guillemot 85 20 105 ↑ ↑ 1968 284 2252 272 33.12 Razorbill 187 40 227 ↑ ↑ 5160 1364 6524 325 95.97 Black Guillemot = ↓ 2 2 2 0.03 Puffin 36 40 76 ↑ ↑ 692 802 1494 85 21.97
227 BIRD RINGING 6 6 : 2 1 8 - 2 3 7 Species 2022 Pullus 2022 FG 2022 Total ∑ x̄ 53-2022 Pullus 53-2022 FG 53-2022 Total Annual Maxima 53-2022 Mean Storm Petrel 152 152 ↑ ↑ 19 1569 1588 321 23.35 Leach's Petrel = ↓ 35 35 4 0.51 Fulmar 5 5 ↑ ↑ 105 56 161 21 2.37 Manx Shearwater 146 1234 1380 ↑ ↑ 8169 40,140 48,309 2243 711.84 Gannet = ↓ 3 3 1 0.04 Shag 239 239 ↑ ↑ 4944 82 5026 243 73.91 Cormorant 5 5 = ↓ 1329 12 1341 128 19.72 Bittern = ↓ 1 1 1 0.01 Grey Heron = ↓ 7 7 2 0.10 Sparrowhawk 4 4 ↑ ↑ 11 114 125 9 1.84 Hen Harrier = ↓ 1 1 1 0.01 Barn Owl = ↓ 9 9 2 0.13 Little Owl = ↓ 45 51 96 8 1.41 Long-eared Owl 3 3 ↑ ↑ 1 26 27 4 0.40 Hoopoe = ↓ 3 3 1 0.04 Kingfisher = ↓ 1 1 1 0.01 Wryneck = ↓ 35 35 4 0.51 Great Spotted Woodpecker 1 1 ↓ ↑ 47 47 7 0.69 Green Woodpecker = ↓ 1 1 1 0.01 Kestrel = ↓ 24 19 43 4 0.63 Merlin = ↓ 10 10 2 0.15 Peregrine = ↓ 56 56 4 0.82 Ring-necked Parakeet = ↓ 1 1 1 0.01 Red-backed Shrike = ↓ 9 9 2 0.13 Isabelline Shrike = ↓ 1 1 1 0.01 Great Grey Shrike = ↓ 1 1 1 0.01 Woodchat Shrike = ↓ 12 12 2 0.18 Red-eyed Vireo ↓ ↓ 2 2 1 0.03 Golden Oriole 1 1 ↑ ↑ 22 22 4 0.32 Jay = ↓ 4 4 2 0.06 Magpie 5 5 ↑ ↓ 270 138 408 29 6.00 Chough 8 8 ↓ ↓ 533 49 582 31 8.56 Jackdaw = ↓ 156 182 338 67 4.97 Carrion Crow = ↓ 335 9 344 16 5.06 Raven = ↓ 66 66 8 0.97 Coal Tit = ↓ 398 398 57 5.85 Willow Tit = ↓ 1 1 1 0.01 Blue Tit 3 3 ↑ ↓ 2 1030 1032 266 15.18 Great Tit ↓ ↓ 24 638 662 62 9.74 Penduline Tit = ↓ 1 1 1 0.01 Woodlark = ↓ 1 1 1 0.01 Skylark = ↓ 15 569 584 119 8.59 Sand Martin = ↓ 22 22 6 0.32 Swallow 28 18 46 ↓ ↑ 1289 872 2161 137 31.78 House Martin 242 242 ↑ ↑ 3 366 369 89 5.43 Cetti's Warbler = ↓ 1 1 1 0.01 Long-tailed Tit = ↓ 351 351 53 5.16 Wood Warbler ↓ ↓ 109 109 7 1.60 Western Bonelli's Warbler = ↓ 8 8 2 0.12 Yellow-browed Warbler 1 1 ↓ ↓ 111 111 14 1.63 Pallas's Warbler 1 1 ↑ ↑ 18 18 3 0.26 Radde's Warbler = ↓ 4 4 1 0.06 Dusky Warbler = ↓ 2 2 1 0.03 Willow Warbler 216 216 ↓ ↓ 6 55,292 55,298 2789 813.21 Chiffchaff 109 109 ↓ ↓ 1 19,365 19,366 859 284.79 Greenish Warbler = ↓ 13 13 3 0.19 Arctic Warbler = ↓ 1 1 1 0.01 Great Reed Warbler = ↓ 2 2 1 0.03 Sedge Warbler 36 36 ↓ ↓ 5 11,376 11,381 644 167.37 Paddyfield Warbler = ↓ 1 1 1 0.01 Blyth's Reed Warbler = ↓ 4 4 2 0.06 Reed Warbler 6 6 ↑ ↑ 185 185 10 2.72 Marsh Warbler 1 1 ↑ ↑ 10 10 1 0.15
228 BETTERIDGE REP. BARDSEY BIRD FLD OBS. Species 2022 Pullus 2022 FG 2022 Total ∑ x̄ 53-2022 Pullus 53-2022 FG 53-2022 Total Annual Maxima 53-2022 Mean Booted Warbler = ↓ 2 2 1 0.03 Melodious Warbler = ↓ 86 86 9 1.26 Icterine Warbler = ↓ 37 37 3 0.54 Lanceolated Warbler = ↓ 2 2 1 0.03 Grasshopper Warbler 2 2 ↓ ↓ 1 1778 1779 197 26.16 Blackcap 236 236 ↓ ↑ 1 8094 8095 728 119.04 Garden Warbler 3 3 ↓ ↓ 1581 1581 112 23.25 Barred Warbler 1 1 ↑ ↑ 19 19 3 0.28 Lesser Whitethroat 1 1 = ↓ 185 185 19 2.72 Western Orphean Warbler = ↓ 1 1 1 0.01 Whitethroat 19 19 ↓ ↓ 19 6546 6565 489 96.54 Subalpine Warbler = ↓ 20 20 2 0.29 Firecrest 3 3 ↓ ↓ 291 291 20 4.28 Goldcrest 177 177 ↓ ↓ 32,205 32,205 2566 473.62 Wren 59 59 ↓ ↓ 48 4757 4805 166 70.68 Nuthatch = ↓ 3 3 1 0.04 Treecreeper = ↓ 52 52 3 0.76 Rosy Starling = ↓ 1 1 1 0.01 Starling = ↓ 36 5507 5543 812 81.60 Grey-cheeked Thrush = ↓ 2 2 1 0.03 Ring Ouzel = ↓ 117 117 13 1.72 Blackbird 21 21 ↓ ↓ 284 9828 10112 550 149.10 Eye-browed Thrush = ↓ 1 1 1 0.01 Fieldfare = ↓ 183 183 16 2.71 Redwing 11 11 = ↓ 5322 5322 554 78.63 Song Thrush 5 5 ↓ ↓ 15 3367 3382 156 49.88 Mistle Thrush = ↓ 13 13 2 0.19 Spotted Flycatcher 6 6 ↓ ↓ 3848 3848 264 56.59 Robin 94 94 ↑ ↑ 73 4837 4910 167 72.26 Bluethroat = ↓ 2 2 1 0.03 Nightingale = ↓ 29 29 5 0.43 Red-flanked Bluetail 1 1 ↑ ↑ 2 2 1 0.03 Pied Flycatcher 4 4 ↓ ↓ 1071 1071 84 15.75 Red-breasted Flycatcher 2 2 ↑ ↑ 50 50 4 0.74 Black Redstart 1 1 ↑ ↓ 81 81 6 1.19 Redstart 1 1 ↓ ↓ 661 661 55 9.72 Whinchat = ↓ 133 133 15 1.96 Stonechat 3 16 19 ↓ ↑ 107 882 989 54 14.60 Wheatear 3 3 ↓ ↓ 589 1420 2009 197 29.54 Isabelline Wheatear = ↓ 1 1 1 0.01 House Sparrow = ↓ 2 483 485 75 7.13 Tree Sparrow 1 1 ↑ ↑ 13 13 3 0.19 Dunnock 33 33 ↓ ↑ 60 1975 2035 95 29.97 Yellow Wagtail = ↓ 14 14 8 0.21 Grey Wagtail = ↓ 30 30 15 0.44 Pied/White Wagtail 2 2 ↓ ↓ 256 638 894 48 13.15 Richard's Pipit = ↓ 1 1 1 0.01 Meadow Pipit 13 13 ↓ ↓ 341 2047 2388 168 35.13 Tree Pipit ↓ ↓ 139 139 12 2.04 Water Pipit = ↓ 1 1 1 0.01 Rock Pipit 27 27 ↑ ↑ 150 1453 1603 95 23.57 Chaffinch 101 101 ↑ ↓ 25 14,460 14,485 957 213.04 Brambling 1 1 ↑ ↓ 704 704 326 10.35 Hawfinch = ↓ 6 6 1 0.09 Bullfinch 1 1 ↓ ↓ 72 72 7 1.06 Common Rosefinch = ↓ 30 30 3 0.44 Greenfinch 1 1 = ↓ 2569 2569 233 37.82 Twite = ↓ 1 1 1 0.01 Linnet 12 12 ↓ ↓ 51 1816 1867 105 27.47 Common Redpoll = ↓ 17 17 3 0.25 Lesser Redpoll 9 9 ↓ ↓ 1 1253 1254 108 18.47 Redpoll Sp. (Common/Lesser) = ↓ 105 105 45 1.54
229 BIRD RINGING 6 6 : 2 1 8 - 2 3 7 Species 2022 Pullus 2022 FG 2022 Total ∑ x̄ 53-2022 Pullus 53-2022 FG 53-2022 Total Annual Maxima 53-2022 Mean Crossbill = ↓ 2 2 1 0.03 Goldfinch 53 53 ↓ ↑ 16 2331 2347 404 34.51 Siskin 16 16 ↓ ↑ 429 429 47 6.31 Lapland Bunting = ↓ 9 9 2 0.13 Snow Bunting = ↓ 1 1 1 0.01 Yellowhammer = ↓ 3 78 81 11 1.19 Ortolan Bunting = ↓ 4 4 2 0.06 Little Bunting = ↓ 7 7 2 0.10 Yellow-breasted Bunting = ↓ 1 1 1 0.01 Black-headed Bunting = ↓ 3 3 1 0.04 Reed Bunting = ↓ 9 266 275 27 4.04 Song Sparrow = ↓ 1 1 1 0.01 White-throated Sparrow = ↓ 1 1 1 0.01 Dark-eyed Junco = ↓ 1 1 1 0.01 Blackpoll Warbler = ↓ 2 2 1 0.03 Summer Tanager = ↓ 1 1 1 0.01 Rose-breasted Grosbeak = ↓ 1 1 1 0.01 Red-headed Bunting = ↓ 1 1 1 0.01 Totals 1124 3119 4243 43,821 263,583 307,404 Number of Species 14 69 75 63 192 196 Long-eared Owl © Ed Betteridge
230 BETTERIDGE REP. BARDSEY BIRD FLD OBS. RECOVERIES, RETRAPS & CONTROLS 1 INTRODUCTION Capturing birds which already have rings on, or finding a dead bird wearing a ring enables the collection of data about birds’ movements around the world, as well as knowing how long they live. When a bird with a ring on is re-captured, the number on the ring can be matched up to its original ringing details, along with any subsequent information collected, thus helping build up a picture of the bird’s travels, history and lifecycle. The more information that is collected, the more accurate an assessment of species’ behaviour and longevity that can be made. 2 METHODS Bird rings are made to fit different species of birds and are therefore produced in various sizes; each ring size is assigned to a species according to the diameter of their tarsus (leg bone) and each ring is stamped with a unique number. When a bird is caught, the appropriate ring size is carefully fitted by licensed ringers, and details are recorded about the bird such as the length of the wing, its weight, the name of the ringer, time, date etc. before releasing the bird back into its natural habitat. Additionally, some species (e.g. Choughs, Rock Pipits, Whimbrels, Shags and large gulls on Bardsey) are fitted with individually identifiable plastic (Darvic PVC) rings with a unique code inscribed on them that can be easily seen in the field, or a combination of plain plastic rings identifying them as individuals. When birds are subsequently trapped, resighted (usually colour ringed birds) or found dead, they fall into one of the following three categories: Data from controls are collected by Observatory staff and sent to the British Trust for Ornithology (BTO) who process them and send back details of the history of the bird with its original ringing details. They also send back information about recoveries of birds that were ringed on Bardsey and re-captured elsewhere. Retrap - a bird that has been both ringed and recaptured at the same site - in this case Bardsey Recovery - a bird that was ringed on Bardsey and subsequently found either at a different site (i.e. away from Bardsey) or dead at the same site, in this case Bardsey Control - a bird found to be wearing a ring which was fitted at a different site - i.e. away from Bardsey
231 BIRD RINGING 6 6 : 2 1 8 - 2 3 7 3 RESULTS This season we received 87 recovery/control reports from the BTO with details relating to birds either ringed on Bardsey and recovered elsewhere, or birds that were ringed elsewhere and controlled on Bardsey. We were also notified about several of our own colour-ringed birds directly from the observers. Below are a selection of some of the most interesting retraps, recoveries and controls from the year. 3.1 KEY TO CODES Age/ Sex codes 1 pullus (nestling or chick) 2 fully grown, year of hatching quite unknown 3 hatched during calendar year of ringing 4 hatched prior to calendar year of ringing, exact year unknown 5 hatched during previous calendar year 6 hatched prior to previous calendar year, exact year unknown 7 definitely hatched two calendar years before ringing 8 hatched more than two calendar years before year of ringing M male F female Condition at recovery + intentionally killed by man X found dead XF found freshly dead or dying XL found long dead V alive, probably healthy; caught and released but not by a ringer VV alive, probably healthy; ring/colour mark read in field but not by a ringer R caught and released by a ringer B caught and released by a ringer – nesting RR alive, probably healthy; ring or colour mark read in field by a ringer S found injured, not known to have been released Sx found moribund (sick or injured, eventually died) Sr found sick or injured, released after rehabilitation with ring A alive, probably healthy - fate unknown AC alive, probably healthy – now captive / / condition on finding wholly unknown
232 BETTERIDGE REP. BARDSEY BIRD FLD OBS. 3.2 RECOVERIES AND CONTROLS OYSTERCATCHER Haematopus ostralegus Pioden y Mor FA71945 5 04.02.2018 Dawlish Warren, Devon Y/5L RR 09.05.2022 Bardsey 1555 days 257 km 339˚NNW HERRING GULL Larus argentatus Gwylan y Penwaig GA00834 1 16.06.1997 Bardsey X 06.06.2022 Pen Y Cil, Gwynedd (ring only found) 9121 days 3 km 51˚NE GA28465 1 26.06.2001 Bardsey X 21.06.2022 Bardsey 7666 days 0 km L E S S ER BLACK - BACKED GULL Larus fuscus Gwylan Gefnddu Leiaf GY25359 1 17.06.2022 Bardsey B:261 RR 07.09.2022 Malpica harbour, A Coruña, NW SPAIN days 1092 km 51˚SSW GY25403 1 24.06.2022 Bardsey B:222 RR 20.08.2022 Santa Cristina beach, Oleiros La Coruña, SPAIN days 1082 km SSW GV56944 1 19.06.2005 Bardsey GN62866 R 29.06.2021 Bryncroes, Gwynedd 5854 days 13 km 45˚NE KITTIWAKE Rissa tridactyla Gwylan Goesddu FX28394 1 03.07.2020 Pointe du Raz, FRANCE G/Y/G RR 30.06.2022 Bardsey R/B 727 days 524 km 0˚N FX28470 1 05.07.2020 Pointe du Raz, FRANCE R/B RR 03.08.2022 Bardsey B/O/O 759 days 524 km 0˚N FX29767 1 10.07.2019 Pointe du Van, FRANCE G/Y RR 29.08.2022 Bardsey Y/G/B 1146 days 524 km 0˚N FX25941 1 07.07.2018 Pointe du Raz, FRANCE R/Y/B RR 16.08.2022 Bardsey G/O 1501 days 524 km 0˚N GREAT BLACK - BACKED GULL Larus marinus Gwylan Gefnddu Fwyaf MA37815 1 22.06.2016 Skokholm, Pembrokeshire W:158 RR 21.08.2022 Bardsey 833 days 104 km 123˚SE MA55565 1 10.07.2021 Ireland’s Eye, Howth, Dublin S67:D RR 31.05.2022 Bardsey 110 days 116 km 134˚SE
233 BIRD RINGING 6 6 : 2 1 8 - 2 3 7 SANDWICH TERN Thalasseus sandvicensis Môr-wennol frechdan DT63288 1 28.06.2019 Hodbarrow RSPB, Cumbria C22 RR 14.08.2022 Bardsey 1143 days 189km 213˚SSW DT04958 1 17.06.2022 Blue Circle Island, Antrim, NORTHERN IRELAND 3A4 RR 03.08.2022 Bardsey 47 days 239km 1165˚SSE RAZORBILL Uria torda Llurs K00295 1 03.07.2010 Sanda Island, Kintyre, Argyll and Bute R 01.07.2022 Bardsey 4381 days 283km 170˚S K21155 1 17.06.2017 Pentland Skerries, Orkney R 17.06.2022 Bardsey 1826 days 668km 190˚S Sandwich Tern © Ed Betteridge
234 BETTERIDGE REP. BARDSEY BIRD FLD OBS. GUILLEMOT Uria aalge Gwylog X59518 1 10.06.1999 Ynys Gwylan Islands X 23.05.2022 Harlech, Gwynedd 8383 days 40km 77˚ENE K00089 1 30.06.2009 Sanda Island, Kintyre, Argyll and Bute R53365 R 23.05.2022 Bardsey 4724 days 283km 170˚S MANX SHEARWATER Puffinus puffinus Aderyn-Drycin Manaw FB55281 4 12.07.2019 Bardsey X 29.07.2022 Southend, Argyll and Bute (possibly HPAI) 1830 days 288 km 349˚N FR94560 1 31.08.1989 Skomer Island, Pembrokeshire FB60620 R 28.04.2022 Bardsey 11928 days 119 km 18˚NNE FB61967 1 04.08.2022 Bardsey R 28.04.2022 Da Praia Grande, São Francisco do Sul, BRAZIL, 75 days 9779 km 207˚SSW Manx Shearwater © Steven Stansfield
235 BIRD RINGING 6 6 : 2 1 8 - 2 3 7 STORM PETREL Hydrobates pelagicus Pedryn Drycin P13267 6 20.07.2020 Burhoa Island, Alderney, Channel Islands R 29.07.2022 Bardsey 739 days 383km 333˚NNW SEDGE WARBLER Acrocephalus schoenobaenus Telor Hesg 8781394 3 03.08.2019 Donges, Loire-Atlantique, FRANCE R 01.05.2022 Bardsey 1002 days 639 km 343˚NNW WILLOW WARBLER Phylloscopus trochilus Telor yr Helyg NVN246 3 02.09.2022 Bardsey R 11.11.2022 Lytchett Bay, Poole Harbour, Dorset 9 days 295 km 141˚SE Willow Warbler © Steven Stansfield Storm Petrel © Steven Stansfield
236 BETTERIDGE REP. BARDSEY BIRD FLD OBS. GREY WAGTAIL Motacilla cinerea Siglen Lwyd ADX1555 3 30.08.2022 Calf of Man, Isle of Man ADB RR 20.09.2022 Bardsey 21 days 145km 180˚S CHAFFINCH Fringilla coelebs Ji-binc S999519 5 03.04.2022 Ballagawne, Isle Of Man R 13.04.2022 Bardsey 10 days 147 km 182˚S GOLDFINCH Carduelis carduelis Nico 5Y12026 5 12.04.2022 Zumaia, Guipúzcoa, Spain R 25.04.2022 Bardsey 13 days 1071km 350˚N Grey Wagtail © Ollie King
237 BIRD RINGING 6 6 : 2 1 8 - 2 3 7 SISKIN Spinus spinus Pila Gwyrdd AAK5781 6 27.03.2022 Mullok, Pembrokeshire R 14.04.2022 Bardsey 18 days 118 km 13˚NNE AHL5631 3 01.10.2020 Keelnacornagh, West Cork, IRELAND R 14.04.2022 Bardsey 560 days 304 km 69˚ENE AHE5713 6 26.04.2020 Bardsey R 14.04.2022 Holylake Shore, Merseyside 749 days 128 km 57˚ENE 3.3 RETRAPS For the purposes of the ‘Retraps’ section: S = Standard recapture of an already ringed bird R= Recapture of an already ringed bird which then had a replacement ring fitted as the original ring was old, and the ring number was becoming illegible. MANX SHEARWATER Puffinus Aderyn-Drycin Manaw FR94560 1 31.08.1989 Bardsey S 08.08.2000 Bardsey FB60620 R 24.04.2022 Bardsey FC05835 1 06.09.1987 Bardsey FB60620 R 19.07.2022 Bardsey FC46574 4 07.08.1989 Bardsey R 05.09.2004 Bardsey FB17778 R 13.07.2022 Bardsey This year, 599 Manx Shearwaters were re-captured: of these, 22 were at least 20 years old and six were at least 30 years old. Some of these are shown above. The oldest Manx Shearwater caught this year was ‘FC05835’; this bird was ringed as a chick making it 33 years old. PURPLE SANDPIPER Calidris maritima Pibydd Du NW04849 1 27.04.2021 Bardsey S 01.05.2022 Bardsey GUILLEMOT Uria aalge Gwylog T25547 1 18.06.1987 Ynys Gwylan Bach R53457 T78484 R53496 R 1 R 23.06.2022 21.06.1996 23.06.2022 Ynys Gwylan Bach Ynys Gwylan Bach Ynys Gwylan Bach
238 STANSFIELD REP. BARDSEY BIRD FLD OBS Section 3 Non-avian reports Striped Hawk-moth © Ed Betteridge
239 NON - AVIAN FAUN A 6 6 : 2 4 0 - 2 5 3
240 KING & STANSFIELD REP. BARDSEY BIRD FLD OBS. Grey Seal © Steven Stansfield NON -AVIAN FAUNA Annotated list of non -avian fauna in 2022 Ollie King and Steven Stansfield RIsso’s Dolphins © Steven Stansfield
241 NON - AVIAN FAUN A 6 6 : 2 4 0 - 2 5 3 Risso’s Dolphins © Steven Stansfield
242 KING & STANSFIELD REP. BARDSEY BIRD FLD OBS. 1 INTRODUCTION Records of species such as mammals, reptiles, amphibians, dragonflies and other miscellaneous species have been collected by the Observatory since it was established in 1953, and more recently these include ongoing Grey Seal monitoring projects, and the extended recording of cetaceans as part of the Observatory’s ongoing dolphin monitoring. Records of non-avian animals that were collected during 2022 are summarised below. 2 METHODS For many of the groups below, data is collected during a daily census, and recorded each evening in the Observatory’s digital census log. Grey Seals were counted daily as part of the census work. Cetaceans were recorded during sea-watches, and also from opportunistic sightings. 3 RESULTS 3.1 VERTEBRATES Halichoerus grypus (Fabricius, 1791) GREY SEAL Grey Seals were counted daily throughout the season, mainly on Henllwyn, Solfach and Carreg yr Honwy. Smaller numbers were also recorded on a regular basis around the South End and the rest of the coastline. The peak counts this year came in August when 262 were recorded around the island on 18th, mostly in Henllwyn where 171 were seen, with two on Solfach, 89 on Carreg yr Honwy and a further 11 on the Narrows and South End. Fig. 1 Daily counts of Grey Seals on Bardsey in 2022 M A M J J A S O Max. count 90 142 197 171 158 262 182 151 Seal-days 645 2015 2245 1405 2257 3907 2447 1486 Days recorded 12 29 31 29 30 30 29 20 In total 62 pups were born in 2022, the first of which was found in Henllwyn on 27 August. This was in the same location as the first pup last year, but almost a whole month later. The last pup to be born was recorded on 20 November. As usual, most pups were born on either side of the Narrows, the rest were distributed further south on both sides of the South End and along the West Coast. Strong winds were less persistent this season; however, small numbers of pups were lost after a few days of strong winds coinciding with spring tides in early September. 0 50 100 150 200 250 300 J F M A M J J A S O N D Daily count
243 NON - AVIAN FAUN A 6 6 : 2 4 0 - 2 5 3 Fig. 2 Grey Seal pups born on Bardsey 1998-2022 0 10 20 30 40 50 60 70 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 Year Annual total Mean Number of pups 28.52 ±s.d.17.39 Grey Seal Pup © Steven Stansfield
244 KING & STANSFIELD REP. BARDSEY BIRD FLD OBS. Fig. 3 Grey Seal pupping sites on Bardsey in 2022 (see Table 1) 46 2 20 7 13 10 35 36 45 28 29 30 41 43 48 4 22 23 24 40 14 5 1 6 8 18 32 39 42 51 52 56 57 59 16 12 49 11 37 44 15 19 25 38 53 17 21 31 55 34 47 54 3 50 58 60 61 62 9 26 27 33
245 NON - AVIAN FAUN A 6 6 : 2 4 0 - 2 5 3 Fig. 4 Number of new Grey Seal pups per day in 2022 Table 1 Grey Seal pupping dates in 2022 (see Fig. 3) Pup Date Pup Date Pup Date Pup Date 1 27/08 17 13/09 33 24/09 49 05/10 2 30/08 18 14/09 34 28/09 50 09/10 3 03/09 19 14/09 35 28/09 51 09/10 4 05/09 20 18/09 36 28/09 52 09/10 5 05/09 21 18/09 37 28/09 53 09/10 6 05/09 22 18/09 38 28/09 54 16/10 7 07/09 23 18/09 39 28/09 55 24/10 8 07/09 24 18/09 40 01/10 56 05/11 9 07/09 25 18/09 41 02/10 57 07/11 10 09/09 26 18/09 42 02/10 58 10/11 11 09/09 27 18/09 43 05/10 59 12/11 12 11/09 28 21/09 44 05/10 60 15/11 13 11/09 29 21/09 45 05/10 61 18/11 14 12/09 30 21/09 46 05/10 62 20/11 15 12/09 31 21/09 47 05/10 16 12/09 32 24/09 48 05/10 0 1 2 3 4 5 6 7 8 9 25/08 30/08 04/09 09/09 14/09 19/09 24/09 29/09 04/10 09/10 14/10 19/10 24/10 29/10 03/11 08/11 13/11 18/11
246 KING & STANSFIELD REP. BARDSEY BIRD FLD OBS. Phoca vitulina Linnaeus, 1759 COMMON SEAL This year there were numerous sightings of Common Seal, involving at least three individuals. The first was sighted on 7 March, then singles were recorded on one day in July, and 21 days in August with two individuals on 6th. Singles were further recorded for 11 days in September and one in October. This species is a vagrant in Welsh waters with approximately 29 records since 1996 (Thompson et al. 2019) but seems to be increasing in number. Common Seal © Steven Stansfield
247 NON - AVIAN FAUN A 6 6 : 2 4 0 - 2 5 3 Phocoena phocoena (Linnaeus, 1758) HARBOUR PORPOISE The first record of the year was a single animal seen off the East Side on 5 April and was followed by seven further records in the month, including the peak count of the year on 26th with a pod of 20 feeding off the West Coast. In May there were four days of records, all of which were single-figure counts. June saw records of individuals on 6th and 15th, with July seeing five records with a peak of ten on 16th. There were records on seven days in August with a peak of six on 9th. September saw five records with a peak of five on 1st, with October producing six records, the last of which came on 15th. M A M J J A S O Max. count 0 20 3 1 10 6 5 3 Porpoise-days 0 50 9 2 20 20 12 11 Days recorded 0 8 4 2 5 7 5 6 Tursiops truncatus (Montagu, 1821) BOTTLENOSE DOLPHIN There was only a single record of this species this year, with two seen together off the North End on 21 March. Grampus griseus (G. Cuvier, 1812) RISSO’S DOLPHIN The first record of the year was a pod of 15 off the West Coast on 27 March. There were three records in April: ten on 3rd, two on 19th and three on 21st. The next sighting was on 6 June when two were recorded. July saw records on six dates, all of which were pods ranging from five to ten individuals. August saw records on 20 dates, including the peak count of 25 on 28 August. In September there were 12 records; most notably a pod of 14 including four calves was seen on 7th, with only one other double-figure record on 9th with 13 individuals. October saw records on seven dates with a peak count of nine on 14th. Risso’s Dolphins © Steven Stansfield
248 KING & STANSFIELD REP. BARDSEY BIRD FLD OBS. M A M J J A S O Max. count 15 10 0 2 10 25 15 9 Dolphin-days 15 15 0 2 42 164 69 37 Days recorded 1 3 0 1 6 20 12 7 Delphinus delphis (Linnaeus, 1758) SHORT - BEAKED COMMON DOLPHIN This species has been generally increasing in frequency and number off the coast of Bardsey in recent years. Following the 107 individuals recorded last year, there was a substantial increase with 554 sighted in total in 2022. The first of the year was a pod of 25 off the West Coast on 4 July. There were eight records in August totalling 403 individuals, including 180 recorded in a single day on 14th (pods totalling 120 and 60 were seen simultaneously). September saw four records with a peak count of 15 on 1st, with October producing six records including a pod of 30 on 2nd. Lagenorhynchus acutus (Gray, 1828) ATLANTIC WHITE - SIDED DOLPHIN A fairly uncommon species in British waters and often seen further out in deeper seas, there were two records this year. The first was recorded on 17 July with a pod of 11 off the West Coast, and the second was a pod of eight sighted on 28 August. Selachimorpha sp. SHARK SP. There were two records this year of breaching sharks that were seen either too distantly or briefly to confirm identification to species level, both of which came in August, on 24th and 28th respectively. Pipistrellus sp. (Schreber, 1774) PIPISTRELLE SP. An individual was seen briefly feeding around Cristin at night on 1 September. Apodemus sylvaticus (Linnaeus, 1758) WOOD MOUSE No specific counts were made this year, although Wood Mice were seen throughout the year, around the buildings and the low walls that cover Bardsey. Sorex araneus (Linnaeus, 1758) COMMON SHREW Although there was no systematic trapping effort undertaken, there was a reasonable increase in records this year. Most records came from hearing their distinctive high-pitched call, frequently at Cristin and Nant. A small family took regular refuge in the compost bins in the front garden of Cristin. 0 5 10 15 20 25 30 0 10 20 30 40 50 60 70 J F M A M J J A S O N D Max. daily count per month Bird-day totals Five day periods Five-day totals Max count