30 July 2023

Barn Owl 2023 update

After one of the strangest springs weather-wise, the Barn Owl season seemed to be all over the place in 2023. We had regular sites unoccupied, non-breeding birds at some sites and some exceptionally late broods. Even now we have a few sites where we need to revisit to ring chicks!

With some new funding from the FiPL project (Farming in Protected Landscapes) managed by the Cornwall AONB, we are continuing to expand our monitoring, this year onto the Roseland peninsula, with some new ringer recruits this year as well from the National Trust.

Our totals for the year were still quite impressive (note we've knocked off a couple of the early years to make space):

2015 2016 2017 2018 2019 2020 2021 2022 2023
Sites visited 41 47 64 85 87 106 93 112
Unoccupied 11 12 23 34 36 43 35 34
Occupied, no breeding 7 8 5 4 3 4 5 4
Average clutch size
(where observed)
4.6 4.6 5.3 5.2 4.7 4.6 4.5 4.5
Average brood size
(where observed)
3.5 2.8 3.0 3.3 3.0 3.2 2.8 3.1 3.2
Chicks ringed 70 47 90 132 119 177 133 189 193
Adults ringed/recaught 17/8 14/9 21/14 18/14 16/15 22/17 19/17 20/22

Unsurprisingly there was again some variety in the brood sizes across the area, with the highest average again along the north coast fared the best though (average brood size of 3.7), followed by the east of the county (3.5, compared to just 2.3 last year) and then 3.0-3.1 elsewhere.

There seemed to be more movement between sites this year, with one adult even on its third site in as many years! The movements between bixes (mostly birds ringed as chicks dispersing) are shown here.

14 July 2023

Stormies on the move

Last month saw us able to mist net Storm Petrels down at Porthgwarra on two nights, catching a total of 119 birds. Of these, 113 were unringed, three were ringed by us in previous years and three were already wearing rings from elsewhere:

  • ringed on Great Saltee Island (Co Wexford) three days earlier
  • ringed on Little Saltee Island (Co Wexford) in July 2022
  • ringed at Torre de Hercules in northern Spain in July 2015, although since then it had managed to lose a foot, a surprisingly regular phenomenon in Storm Petrels!

Two birds we ringed on the same night were also recaught 21 days later on Bardsey, also on the same night! Another was then recaught on Lundy Island 29 days later, alongside birds we'd ringed here in July 2016, June 2017 and August 2020, which may well now be recruited as breeding birds on the island.

Hopefully more Stormies to come next week, with a public ringing session likely to be on Monday or Tuesday, so see here for details.