Phylloscopus trochilus – TELOR YR HELYG – Breeding summer visitor and passage migrant.
Previous records summarised in Willow Warbler 1994
| Year | First | Last | Notes |
| 1993 | 25 March | 19 October | |
| 1994 | 29 March | 15 October | |
| 1995 | 24 March | 19 October | |
| 1996 | 24 March | 9 October | |
| 1997 | 23 March | 17 October | |
| 1998 | 21 March | 7 October | |
| 1999 | 30 March | 28 October | |
| 2000 | 16 March | 20 October | |
| 2001 | 27 March | 21 October | |
| 2002 | 25 March | 21 October | |
| 2003 | 17 March | 14 October | (1) |
| 2004 | 28 March | 8 October | |
| 2005 | 22 March | 22 October | (2) |
| 2006 | 1 April | 6 November | |
| 2007 | 6 April | 11 October | |
| 2008 | 31 March | 13 October | |
| 2009 | 21 March | 31 October | |
| 2010 | 3 April | 3 October | |
| 2011 | 26 March | 16 October | |
| 2012 | 3 April | 23 October | |
| 2013 | 29 March | 22 September | |
| 2014 | 27 March | 14 October | |
| 2015 | 27 March | 20 October | |
| 2016 | 28 March | 26 October | |
| 2017 | 19 March | 27 October | |
| 2018 | 30 March | 18 October | |
| 2019 | 24 March | 13 October | |
| 2020 | 23 March | 10 November | (3) |
(1) 2003 – Remarkably, a wintering bird present Monk’s Haven 14 Feb (SED). This is the second winter record for Pembs, following one singing at Stackpole 9 Feb 1991.
(2) 2005 – Final record appeared to be Angle Bay 22 Oct but then another found lingering at The Rhos 5 Dec (J&MB). Only the 3rd record of wintering in the county, the others being in 1991 and 2003.
(3) 2020 – Latest record for Skokholm
