Llanelli Naturalists Newsletter - June 1996
R Jenkins

Introduction

Phragmites  reed beds are an important habitat type of particular importance to birds (Bibby & Lunn 1982), and  bird ringing studies in South Wales have provided a valuable insight into the ornithological importance of these reed beds (Stewart, 1990).

The majority of bird ringing occurs during the summer months (July-September), with a reduction in effort during the colder winter months.  Reed beds are not only important for breeding birds, they also provide suitable habitat for many winter residents such as the Water Rail Rallus aquaticus.

Bird ringing at Ffrwd Fen SSSI, Pembrey (Carmarthenshire., vc44) during 1995 aimed to continue previous studies of Acrocephalus warbler movement in the Llanelli area (eg Ormerod, 1990) and to provide an insight into the abundance of Water Rail.

Methods

A lack of resources dictated lower effort than previous studies (Ormerod, 1988).  Four early morning and three evening visits were made between 10.7.95 and 17.8.95.  During the morning visits 150 feet of mist netting was used.  In the evenings only 40 feet was employed, in conjunction with a Swallow roost tape lure.

Riddle clap-traps (de Kroon, 1979) baited with mealworms were used to catch Water Rail in four periods (Table 1).

Results

166 birds of 16 species were caught and ringed in mist nets (Table 2).  In addition, four of the birds caught were already ringed.  Two of these were Reed Warblers previously ringed at this site (E756356:  caught on 10.7.95 was first ringed 30.4.89 and H848147 caught on 28.7.95 was first caught on 19.8.92; B Stewart pers. comm.).  Another Reed Warbler and a Sedge Warbler had rings from different origins and I am currently awaiting details of the initial ringing locations.

A total of 21 Water Rail (and a Moorhen) were caught and ringed during 1995 (Table 3).  Six recaptures occurred during the same period as ringing (eg 4 of the 9 birds ringed during period A were recaptured during period A).  Of more interest are the between period captures (Table 4).

Discussion

Too few birds were caught to ascertain patterns in Acrocephalus warbler movements.  The ringing of Acrocephalus warblers in South Wales continues to highlight the importance of relatively small reed beds (Tyler 1994).  Even small sites and a low amount of ringing effort can serve to indicate the relative importance for these sites for passage birds.

Winter ornithology in reed beds is a neglected pastime.  Birds such as Water Rail which are notoriously difficult to observe, are easy to catch in traps.  Results from this study suggest that Ffrwd Fen SSSI had a minimum of nine Water Rails during the winter.  This is certainly an under estimate.  Of particular interest are the two birds caught in February 1995 that were subsequently retrapped in the winter of the same year.  Although it is impossible to comment on their whereabouts during the breeding season, evidence of wintering site fidelity, such as this, is important information on this little-studied bird.

References

Bibby, CJ and Lunn, J (1982).  Conservation of reedbeds and their avifauna in England and Wales.  Biological Conservation 23, 167-186.

Ormerod, SJ (1988).  Ringing around Llanelli.  Llanelli Nats. Newsl., Winter 1989-1990, 18-23.

Ormerod, SJ (1990).  Time of passage, habitat use and mass change of  Acrocephalus warblers in a South Wales reedswamp.  Ringing and Migration 11, 1-12.

Stewart, B (1990).  Bird ringing in Carmarthenshire 1989-19909.  Llanelli Nats. Newsl., Winter 1990-1991, 27-29.

Tyler, SJ (1994).  Reed-beds in Wales.  Their extent and distribution, their birds and threats facing them.  RSPB Report