Oxwich Ringing Report 2015 – Gower Ornithological Society

2015 was the third year of Gower Ringing Group activity
at Oxwich Marsh. It proved to be another good one: group members put in a lot of effort, and were rewarded by some excellent returns. A summary follows, and a more detailed report can be accessed through following the link towards the bottom of the page.

Kingfisher (Keith Vaughton)

We managed to keep up the impetus of 2014 and completed twice weekly sessions during passage periods and weekly sessions at other times (whenever weather allowed). As a result, the number of birds ringed on the marsh increased (on the 2014 total of 3,371) to 3,531, and 3,925 unique birds were processed during the calendar year (this total includes birds recaptured and controlled for the first time during the year but excludes multiple recaptures).

The data set that is emerging is both valuable and interesting. It indicates, for example, that while the site currently supports relatively small numbers of breeding reed and sedge warblers, far larger numbers occur during autumn passage. While some of these warblers have been controlled at sites to the south and south-east (along a relatively intuitive broad front migratory corridor), others appear to head off in the wrong direction, as we have recovered fledglings recently ringed at Kenfig (to the east) at Oxwich, while some of our birds have headed north west to the Teifi Marshes in Pembrokeshire after fledging. Perhaps more surprising than apparent navigation errors in these juvenile warblers, however, was the recovery of a Cetti’s warbler ringed at Magor Marsh, Monmouthshire in 2012 at Oxwich (a movement of almost 100 km). It does illustrate that Cetti’s warblers are capable of dispersal, as they have had to be to colonise much of England and Wales over the past few decades, despite their stubby wings.

Redwing (Charlie Sargent)

The data also indicate that species such as tree pipit and garden warbler have very short periods of (relative) abundance locally, and poor weather during these periods can influence annual catch rates considerably – catches of both decreased in 2015. It will be interesting to see how the totals shape up in 2016. Between year differences have also been very apparent in late autumn immigrants, with the 167 goldcrests captured in 2015 more than doubling the 78 birds trapped in 2014, and reflecting widespread reports of a significant autumn influx of the species to the UK. Similarly, despite unsettled weather, we managed to capture 99 redwing at the marsh this year, compared to a paltry eight in 2014.

It has also been nice to capture a few old stagers, including a seven year old male reed bunting, a dunnock of the same age, and a couple of six year old blue tits. All were ringed by the previous ringing incumbent of the marsh, Barry Stewart, who was active on the site until 2010.

Whinchat (Keith Vaughton)

Redstart (Keith Vaughton)

New species
for the site in 2015 were green woodpecker (two), mistle thrush, pied/white wagtail (both races), redstart, whinchat
(two), nuthatch (two), and lesser redpoll (seven), while other highlights have included three firecrest, two jack
snipe and proving local breeding in grasshopper warbler. Totals of sub-Saharan migrants included 399 barn swallow, three tree pipit, two whinchat, a redstart, 11 grasshopper warbler, 145 sedge warbler, 159 reed warbler, two lesser whitethroat, five garden warbler and 84 willow warbler. Shorter distance migrants and resident species have included three kingfisher, 65 meadow pipit, 24 Cetti’s warbler, 100 chiffchaff, 190 blackcap, 469 blue tit (!), and 147 reed bunting. Finch numbers were consistently high, with 464 unique goldfinch and 468 greenfinch captured over the year, while two distinct cohorts of young siskin were recorded, indicating a first brood that fledged in May and a second in July.

Grasshopper warbler (Owain Gabb)

Maintaining the effort in 2015 has only been possible due to the commitment of Gower Ringing Group members, who also run two Constant Effort Sites and a Re-trapping Adults for Survival project on pied flycatcher. As the group is relatively small, and individuals also have additional projects, this effort continues to be very much appreciated. The site provides an excellent opportunity for training, due to the numbers of birds and the diversity of species captured (we are now up to 55 species ringed at Oxwich since we began ringing the site in February 2013), and our trainees also benefit from this commitment in terms of experience. The relatively large and varied catches also encouraged the BTO to hold the Welsh Ringing Course on the site for the first time in September 2015. Despite bad weather the feedback from participants was overwhelmingly positive, and over 400 birds were captured in three days.

The other critical factor in keeping the ringing effort going has been a Gower Society grant, which has done much to cover the cost of rings and seed (for the feeding station). We are extremely grateful for the support of the Society in 2015.

Many thanks to all the ringers and helpers who have contributed so much this year, to the land managers, Natural Resources Wales, for their support, and to the Gower Society for grant funding. 2016 should be another great year at Oxwich.

Some further photographs are below, and the full report can be found by following this link (to a page where the PDF’d report can be downloaded):

http://www.bsg-ecology.com/oxwich-marsh-bird-ringing-report-2015/

Owain Gabb

04/01/2016