• Some species, such as sparrowhawk, water rail and starling, are captured relatively randomly. They are around the marsh all year, sometimes (in the case of starling) in very large numbers. However, we don’t deliberately target them at present.  
• Snipe numbers are well up in 2017. This partly reflects less water in the marsh, which may in turn reflect both less rainfall locally, and changes in water level management by Natural Resources Wales (NRW). When water levels are low in autumn, winter and early spring, it is more feasible to put net in areas of wet reed bed. Snipe day roost in these areas. The snipe favour areas that have been trampled down by cattle (at least for dropping into at or before dawn); in 2017 cattle have been absent in the autumn, and we have been able to manipulate snipe distribution by strimming some suitable areas (to create open patches surrounded by tall reed). Jack snipe also day roost in these areas. It follows that the decrease in jack snipe numbers in 2017 may, in fact, reflect a real local decline in 2017, or it may be coincidental. From less than 2:1 snipe to jack snipe in 2016, we are at a ratio of approximately 5:1 in 2017.
• For house martin, swallow, meadow pipit and all species of wagtail, the higher ringing returns in 2017 reflect increased effort to target these species. House martins will sometimes come to a tape lure in late summer / autumn (and we had one very good day in 2017); we completed more roost visits for swallows and wagtails in 2017; and, due to having more trainees (who would benefit from the experience), we also looked to capture more meadow pipits this year during quiet periods.
• Some resident species seem to have had a more productive year at the local level in 2017 than they did in 2016. These include dunnock, blackbird, blue tit and robin. This is reflected in far higher numbers of these species.
• Some changes are likely to have been due to relatively short term weather patterns. The number of tree pipit and garden warbler we capture clearly reflects the effort we put in, but also the amount of optimum weather for capturing them between mid August and early September (the peak passage period for these species in Gower). Sedge warbler and willow warbler numbers also appear quite markedly different, but a few big autumn catches typically significantly influence overall totals of these species (e.g. we captured 44 willow warblers on 14 August 2016 and had two other dates on which 20 or more were captured – the maximum day capture in 2017 was 23 birds). Finally were also unable to get a session in in early October, when an influx of firecrest occurred locally, and have captured our only two individuals of this species in 2017 in late November and early December respectively (far later than in previous years).
• For some species, influxes are variable between years; redwing (more present in 2017) and yellow-browed warbler (more present in 2016) are the most obvious examples of this in the data presented. 2016 and 2017 have both been modest years for goldcrest. In 2015 we captured over 160 birds during a substantial late autumn influx.
• A few species may actually be declining at the local level. Greenfinch numbers have dropped each year for the past few years, suggesting trichomoniasis (which is rife in Gower) is causing a population-level impact. Effort to capture them has been a little variable, but not enough to account for the changes in numbers observed. Chaffinch and goldfinch numbers have also dropped in 2017 (albeit a good December may see us catch a good few more of both), which may simply be between year variation; this is something we need to monitor. 

Owain Gabb
03/12/2017

Photos (taken by Kirsty Franklin) are below.

Bullfinch (our 14th of an above average year for the species).

Our latest firecrest to date (captured on 2 December 2017)