Llanelli Naturalists Newsletter - December 1984
Geoffrey Evans

The first arrival dates for many migratory species were tabulated in ‘Bird Notes’ of the June 1984 Llanelli Naturalists Newsletter but the availability of the national dates and patterns in the YOC "Spring Migration Phone-in Report" makes comparison interesting.

The impression gained when comparing this information was the consistent match of arrival dates, both local and national e.g. on 15 April was recorded the first local Common Sandpiper at the 'Ashpits Pond' - this matched the week 14-20 April given as the first main arrival period nationally (i.e. over 10% of submitted records), likewise the first solitary Swallow was seen at Machynys on 3 April when a few were noted over South and South-east England; it was described as 'widespread in Carmarthenshire' by 15 April, a date re¬flected by the national main first arrival date of 14-20 April. This coincidence of arrival dates is in fact repeated with most of the species involved with only a few deviations such as the Spotted Flycatcher at Tywyn Point on 20 April only 7 days after the 1st national records (Worcs.) and a full month before the main mass of arrivals. Another interesting point to emerge was that the Black Redstart at Machynys on 20 March was probably part of a passage that was first noted in Cornwall on 17 March.

As a further refinement to our arrival dates for 1985 we should differentiate between the first passage migrants e.g. (in 1982) the Chiffchaff recorded by the Witchett Pool on 25 March and the arrival of local breeders in suitable breeding habitat as at Stradey Woods on 28 May. In 1984 the single April 3rd Swallow at Machynys was obviously a passage bird whilst those at a regular nest site on 12 April at Mynydd Penbre, were local breeders newly returned.

When we have sufficient data over a period of years it will be useful to compare year with year and try to discern any trends e.g. whether any species are declining as it has the Sand Martin which was reduced in numbers by about 70% from 1983 to 1984 and numbers of which are less than 10% of those of twenty years ago. (Much of this information is supplied by the invaluable BTO 'Common Birds Census'). The same census showed that in 1982, the Pied Flycatcher was up by about 25% - we certainly had ample records of this species in 1984, but no true first arrival date. Willow Warblers and Lesser Whitethroats also occurred in increased numbers this year; the latter which winters in East Africa, migrates in Spring in a North-west direction via the Middle East and South-east Europe and this year, South-east winds in April, helped push up the numbers in Carmarthenshire, for normally we are at the edge of this species' breeding distribution.

Sites on the coast such as Tywyn Point, Burry Port and Machynys often produce the first arrival dates for species like Swallow, Sand Martin, Willow Warbler and Wheatear, for others e.g. Wood Warbler, Tree Pipit and Pied Flycatcher it may be necessary to repeatedly visit the breeding area until one has the first arrival date.

It is worth recording the following data:

1. Date of first record
2. Numbers
3. Whether passage birds or on breeding territory
4. Date of main influx(es)
5. How do numbers compare with previous years
6. Dates of any 'falls' of migrants
7. Weather conditions of the day/week i.e. southerly warm winds, etc

Departure dates - when a species is last seen in summer (including when last commonly seen) and notes on passage birds e.g. Linnets, Skylarks, and Goldfinches in Autumn are also invaluable. Remember that some species e.g. Linnet, Goldfinch and Song Thrush which are present throughout the year, as a species but not as individuals, often have greater numbers wintering abroad; and the arrival dates of passages by those species in spring should also be recorded. Also some birds that overwinter '.ere are not necessarily local breeders, e.g. wintering Blackcaps in Britain are said to be of Central European origin.

Given below is a comparative list of the Carmarthenshire and national arrival dates, details of observers and localities can be seen in the June 1984 Llanelli Naturalists Newsletter. If anyone wishes to take part in the YOC '1985 Phone-in' they should send their records to me (write please not phone) by say, mid May (or earlier) 1985 or they can phone The Lodge, Sandy (0767 80551) between 5.30-7.30 p.m. on Tuesday between 19 March-14- May.

Looking forward to next spring

    Carmarthenshire    British Isles

Common Sandpiper    15-Apr    14    -    20    Apr    M

Common Tern    21-Apr    21    -    27    Mar    M

Cuckoo    20-Apr    14    -    20    Apr    M

Chiffchaff    31-Mar    3    -    6    Apr    M

Willow Warbler    10-Apr    14    -    20    Apr    M

Swift    30-Apr    28-Apr    -    4    May    M

Sand Martin    12-Apr    14    -    20    Apr    M

Swallow    03-Apr    South & South-east England, few

Swallow    15-Apr    14    -    20    Apr    M

House Martin    23-Apr    21    -    27    Apr    M

Yellow Wagtail    18-Apr    14    -    20    Apr    M

Wheatear    01-Apr    31-Mar    -    6    Apr    M

Sedge Warbler    22-Apr    21    -    27    Apr    M

Whitethroat    19-Apr    21    -    27    Apr    M

Blackcap    08-Apr    14    -    20    Apr    M

Black Redstart    20-Mar    17-Mar                Cornwall

Redstart    17-Apr    14-Apr                onwards

Whinchat    22-Apr    21    -    27    Apr    M

Grasshopper Warbler    20-Apr    14-Apr                onwards

Reed Warbler    06-May    21-Apr                onwards

Lesser Whitethroat    23-Apr    around 22-Apr               

Garden Warbler    22-Apr    around 20-Apr               

Wood Warbler    23-Apr    21    -    27    Apr    M

Spotted Flycatcher    20-Apr    13-Apr                Worcs, M late

(M = first main arrivals)

N.B. list not in chronological order.