It is interesting to know that at least one LSW is still being seen in N Pembs (hopefully breeding!) in a general area they were known from (a stronghold would probably be over-stating things a bit) back in the 1984-88 local breeding birds atlas period. Yet, they may have been less numerous in this area in the 2003-07 repeat local atlas period, when there were more sightings in the E Cleddau catchment, for example, than during the earlier atlas period.
However is this a true picture, or more of a case of good observers, who know this elusive species well, being in the right place at the right time? (See composite distribution map). Orange squares = 1984-88 distribution; black dots = 2003-07 distribution (smallest being possible breeding, largest being confirmed).
During 2003-07 we did register records from a number of tetrads across no less than eleven 10 km squares (actually one more 10 km square than in the earlier atlas period!) But what is the current situation for the current national atlas (BTO Atlas 2007-11)?
Over the last 3 seasons we have received just five individual records (one from SN01 10 km sq; one from SN02 10 km sq; and three from SN13 10 km sq). In other words the LSW is currently missing from at least seven or eight 10 km squares! Has the population really dropped so dramatically since the mid 2000's? Or is it a case of under-recording a species that has always been fairly difficult to find and generally present at quite low density?
If you are aware of places where you know LSW's do occur in the County (or in adjacent Carms for example) then please do try to add these to the current atlas on-line to provide a clearer more up to date picture. Such records are so important at both national and local level.
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