Scientific: Mergus merganser

Cymraeg: Hwyaden Ddanheddog

A recently established breeding species in the Tywi and Cothi Valleys. More widespread in winter.

1982
Remarkable increase in breeding pairs, since first suspected nesting in 1979, confirmed, 1980. This year, 3 pairs, Rhandirmwyn area, raised broods of 8, 9, and 10 respectively. Single pairs presumed to have nested near Llanwrda; near Dryslwyn and on River Cothi, 9, (mostly `redheads’), Dinefwr, 25 January and 18 February; 3, Talley, 25 January; 8 (3 males), Llanegwad, 4 March; 8, Dryslwyn, 12 December.; 4, Rhandirmwyn, 12 December..

1983
Regular on the River Tywi from Nantgaredig to Llyn Brianne. Bred on the River Tywi, Near Rhandirmwyn, females seen with 7 and 6 young respectively; another successful pair near Llanwrda; 1, probably 2 pairs bred on the Dinefwr-Dryslwyn stretch as well as a female with 13 young seen on the River Cothi, North of Pontargothi, 7 August. Winter and spring maxa, 8, Dryslwyn, 13 February and 27 November; 14 near Pont Cilsan, 6 April; 7, Dinefwr Ponds, 29 December. A female, at Pownd Twym (Old Castle Pond), Llanelli throughout December. A male, Blaen Wysg (Usk) Reservoir, 26 December.

1984
At least 6 pairs known to have nested at the following localities, 3 pairs, Rhandirmwyn reared 13; 1 with 6 young Dryslwyn, 26 June; 1 with 7, River Cothi between Crugybar and Pumsaint, June; 1 nested high in an oak, Cwrtycadno; nesting female flushed several dates, May/June, Castle Woods Reserve. 5 (2 males), Dinefwr Ponds, 27, 8, 29 April 5 (4 males) 3rd, 12 (10 male) there and adjoining River Tywi, 15 May. Widely reported on River Tywi and its tributaries including headwaters e.g. female, River Sawdde, Pontarllechau, 1 & 2 February. Elsewhere, female, Pownd Twym (Old Castle Pond), Llanelli and Lliedi Reservoir, January – 2 March. Highest totals, 11, Cilsan, 24 May; 9, Talley, 26 February ; 7 (redheads) Blaen Wysg (Usk) Reservoir, 17 March & 15 September; 12 (redheads) River Tywi, Llandeilo Rhwnws + 3 Dryswlyn, 16 October 3, River Llwchwr, Pantyffynnon, 28 December.

1985
10 pairs known to have bred on River Tywi at following localities, 5 pairs, Rhandirmwyn; 2, Llanwrda; 2, Dryslwyn; 1 (probably), Castle Woods, Llandeilo. No records for River Cothi. RSPB Summer Goosander County 1985, gave total of 66 females and brood for River Tywi. Males were rarely reported after May as it is probable that they migrate to Finmark to moult. Early year totals, female, Lliedi Reservoir, 18 January; 7 (3m), Dryslwyn, 11 & 28 January 9 (4 males), 8 February; 14, Talley, 24 February; 9, Dinefwr Ponds, 9 March; 7, Llandeilo Rhwnws +7, Gelli Aur, 28 October; 8 (3 males), there 4 December.

1986
The R.S.P.B.`s two reports, “Goosanders on the Afon Tywi” a) Monthly Counts of Goosanders and other Piscivores, February 1986-January 1987, and b) Mortality and Movements of Broods May-August 1986 (S.J.Tyler 1987), found 12-13 pairs of Goosanders attempting to breed on the Tywi, and its tributaries. 2-3 broods were thought to have failed from unknown factors, 65 well grown young in late July, resulted from the 10 other broods. Goosander totals each month were 46, February 23-32, March-June, 65, including broods in late July, 49, August 49-55, October-December. Elsewhere 24, Talley, 12 January; 2-3 River Teifi Cwmann (joint county) January-February; 3, Blaen Wysg Reservoir (joint county), 15 March; 4, River Brân, Cynghordy, 5 November; male, off Pembrey Harbour, 25 November.

1987
Preliminary reports of the “British Trust for Ornithology Sawbill Survey”, suggest 11-13 pairs attempting to breed on the River Tywi and its tributaries, with what success is not known. Monthly maxa, 10, Tâf estuary, January; 21, Rhandirmwyn, 8 February, 6 redheads, River Tywi, Dryslwyn, 12 March; 7 River Cothi Abergorlech, 28 April; 19 (10 males), Dryslwyn, 9 May; female + 7 young, Llansawel, June 12/15 including young, Aber Cothi, 15/16 August; 15 Talley, 28 December.

1988
Bred on River Tywi and tributary Cothi, seen also on the Dulais, Brân and Nant Melyn as well as River Teifi, October-December. Several adults with young seen, 1 with 14 young, Maenor Deilo, 20 June. Maxa, 14, Talley 26 January; 25, River Cothi, near Brechfa, April.

1989
Several broods of up to 14 ducklings seen on River Tywi and River Cothi. River Teifi breeding season sightings, 4 redheads, Pont Henllan, 8th, a duck, 22 April; 5 redheads, Llanfihangel ar Arth, 6 June. Maxa aggregations 16, River Tywi, Dryslwyn, 9 May, 24, 4 September.

1990
4 broods numbering 12, 12, 11 and 6 as well as 10 non-breeding birds seen on River Tywi, Llandovery-Llandeilo in early June. A brood of 5 on River Cothi, Pumsaint; of 6 on River Marlais, Llansawel of 4, Rhandirmwyn, June; pair River Brân, Cynghordy, mid-late April.

1991
Fewer broods seen on River Tywi, 2 near Rhandirmwyn, 1 near Llanwrda May/June, with 22 mainly if not all males there 25 August. 20 Dryslwyn 27 April; 7 River Teifi near Lampeter 16 May; 14 Witchett 26 November.

1992
At least 2 pairs bred at the Gwenffrwd/Dinas Reserve, with one rearing 9 young. Six broods were noted on the Tywi between Llandovery and Llandeilo.

Notable counts on the Tywi were; Cilsan Bridge: 14 (5 males) on 17th April, Dryslwyn: 14 on 3rd May, Dinefwr Ponds: 18 (14 males) on 13th May and Manordeilo: 20 on 21st June. Small numbers were noted on the Loughor (3 at Pantyfynnon on 19th March), and Cennen (a pair at Derwydd on 14th March). Other records were at Talley: 5 on 17th February; Cynghordy: 15 on 8th August and Ferryside: 1 on 20th September.

1993
Six broods were noted on the Tywi between Llandovery and Llandeilo and a pair raised 8 young on the Gwenffrwd /Dinas Reserve.

Other counts along the Tywi were 8 at Cilsan Bridge on 6th February and 24 at Dryslwyn on 2nd May. Elsewhere there were 5 (3 males, 2 females) at Witchett Pool on 31st Oct and a large winter count of 31 at Llyn Pencarreg on 25th November.

1994
A good year for breeding birds with 11 broods noted on the Tywi between Llandovery and Nantgaredig and 2 broods on the Cothi in the Glanrannell Bridge district. A dead female (with eggs inside) was found in the Gwenffrwd valley on 18th April. Spring display was frequently witnessed at Pontydolau, Maesycrugiau over the river Teifi.

Flocks observed included 5 at Witchett Pool on 10th January and c.40 flying to roost at Dinefwr Ponds on 17th January. Twenty five were noted on the Tywi at Ro-fawr from Dryslwyn on 22nd May and 8 on the Teifi at Maesycrugiau on 25th November. Smaller numbers were also noted at Talley, Llandeilo and Cynghordy.

1995
Five broods were noted on the Tywi between Llandovery and Dryslwyn and a female and 12 young on the Cothi at Pumpsaint. Eight were displaying on the Teifi at Maesycrugiau on 13th March.

Flocks observed included 60 flying to roost at Llandeilo on 26th August and 16 at Pontargothi on 13th September. Two at Pembrey Harbour on 3rd December were an unusual record for the site.

1996
The only breeding record received was of a female with 5 young on the River Gwenffrwd on 16th June. A male at Cydweli Quay on 10th March was an unusual record for the site, whilst the only notable counts were of 9 (8 males) at Dinefwr Ponds on 22nd May, 11 there on 15th September and 6 at Llyn Pencarreg on 13th October.

1997
Two pairs bred on the Gwenffrwd/Dinas Reserve one rearing 5 young and at least 2 pairs bred on the upper Cothi. A female with a brood of 10 was seen on the Teifi at Maesycrugiau on 4th June, 2 broods were seen on the Tywi at Rhosmaen on 27th.

Outside the breeding season sizeable counts were of 10 at Cilsan Bridge on 1st January, 8 at Dryslwyn on 14th March and 12 on the Tywi between Nantgaredig and Llanegwad on 4th April.

1998
Five broods were seen on the Tywi between Dryslwyn and Rhandirmwyn with a brood of 10 noted on the Teifi. 13 were seen on Llyn Pencarreg in April.

1999
On the Afon Tywi a brood of 10 were seen at Ty-Picca on 11th July. In the north of the county on the Afon Teifi at Maesycrugiau a family group of 5 turned up during the breeding season.

2000
A pair was present on the Bran at Cynghordy during the breeding season, but there was no evidence of successful nesting. The only notable counts were of 19 at Dinefwr Ponds on 12th May, 21 at Pentre Davis on 29th June and 25 on the Tywi below Dinefwr Park on 26th August. A female remained at the Ashpits Pond from October to the end of the year.

2001
Recorded in six out of twelve months at Usk, there was a maximum of 5 on 2nd January. A female noted on 24th February resided at Ashpits Pond for a while. 1 male and 7 redheads were seen at Talley Lakes on 25th February. Birds were present in the breeding season at Cynghordy. A pair was recorded at Pont Cydrych, near Cwm Isfael on 13th April, the female investigating holes among boulders. Another report possibly involving breeding was of a female flying to a tree in Dinefwr Park, but as with the previous instance no further information was gleaned. In June more tangible proof of breeding came in the form of 1 female and 2 juveniles at Ro Fawr on 12th. It is likely that the female and 2 juveniles seen at Dryslwyn on 23rd June were the same birds. 5 redheads at Upper Loughor on 14th December was the last record.

2002
Recorded in five months at Usk Reservoir, there was a maximum there of just 2, on 9th February and 9th November. Maximum count overall was 27 at Talley Lakes on 19th December. The only first winter period record came from Llyn Pencarreg, 13 on 19th January. They were also noted there – 4 and 9 – on 12th October and 19th December, in that order. The Afon Dulais, Taliaris produced a pair on 8th April. Otherwise, on the Towy. 20 and 22 at Dinefwr oxbows, on 18th July and 11th August respectively; 9 at Llangadog on 11 December and 17, including 11 males, at Dryslwyn on 30th December comprised counts elsewhere.

2004
In the early part of the year at Llyn Pencarreg there were 5 males and 2 females January 1st and 4 males and 8 females on Jan 25th. Breeding activity reported with a female near RSPB Dinas reserve May 16th, a pair with 10 ducklings at Cilsan Bridge June 3rd and a female and 5/6 young Dryslwyn June 5th. Later 4 males and a female were at Llandeilo Bridge November 11th, 5 Kidwelly and a single at Dryslwyn December 6th and 4 Usk Reservoir December 9th.

2005
Four Dryslwyn and a single Cilsan Bridge January 10th and 20 including 17 “redheads” at Tanerdy Jan 30th. Proof of breeding was received by a nest found at Pentre Davis which contained 10 eggs, a female with 6 newly fledged chicks at Llanwrda May 9th and counts of up to 40 juveniles in total along the Tywi.

2006
Regular breeding species especially in the Tywi and Teifi valleys. More widespread in winter.

Breeding well in the Tywi Valley and its tributaries where 4 were noted Talley Lakes March 11th and 7 juveniles were seen at Cilsan Bridge July 19th. Ten together at Upper Loughor December 19th.

2007
The Tywi is the headquarters of this attractive duck in the county so it is not surprising to hear of good numbers from Cynghordy down to Dryslwyn as well as others on the tributaries. Up to 10 were on a farm pond at Cynghordy in January /February and there was speculation as to whether they were feeding on frog spawn or indeed the frogs themselves. Females with ducklings were noted at Dryslwyn (6 young) April 30th, Pentre Davis (10 young) May 16th, Cilsan Bridge (4 young) June 10th, Dryslwyn (7 young) June 15th and Dolgarreg (11 young) June 26th.

A pair was reported from the Teifi at Newcastle Emlyn February 4th perhaps surprisingly a female was on the glacial lake at Llyn y Fan Fawr August 17th. Two females were in Pembrey Harbour December 4th.