Red-Crested Pochard
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Red-crested Pochard Naturalised introduction Netta rufina International threshold: 500 † Great Britain threshold: ? GB max: 243 Oct All-Ireland threshold: ?† NI max: 1 Feb Red-crested Pochard is a patchily in 2007/08. Cotswold Water Park remained distributed species throughout central and the premier area in the UK maintaining a southern Europe where it is considered to five-year mean peak of approximately 200 be largely sedentary. Hence the majority of birds across the whole complex of gravel British records, including those pertaining pits. The species was recorded at a further to the ancestors of the core of the UK 52 sites elsewhere in England, five of which population at Cotswold Water Park, are registered double-figure counts. generally considered to relate to escapes. A single was recorded at Upper Lough Having undergone a doubling during the Erne in February; only the second WeBS preceding four years, numbers counted record for Northern Ireland, following one during WeBS Core counts surprisingly took a at the same site in February 2006. small dip across most of the principal sites 03/04 04/05 05/06 06/07 07/08 Mon Mean Sites with mean peak counts of 10 or more birds in Great Britain† 13 Cotswold Water Park (West) 114 81 119 207 170 Nov 138 Cotswold Water Park (East) 33 48 70 106 72 Oct 66 Lower Windrush Valley Gravel Pits 6 19 41 26 (26) Jan 24 Baston and Langtoft Gravel Pits (23) (23) Arnot Park Lake 12 19 18 16 14 Sep 16 Sutton and Lound Gravel Pits 6 16 12 22 13 May 14 Hanningfield Reservoir (7) 2 21 17 10 Apr 13 Sites below table qualifying levels but exceeding threshold in WeBS-Year 2007/08 in Great Britain† Colne Valley Gravel Pits 2 3 8 23 10 Dec 9 † as no British or All-Ireland thresholds have been set a qualifying level of 10 has been chosen to select sites for presentation in this report Red-crested Pochard (Neil Calbrade) 82 Pochard International threshold: 3,500 Aythya ferina Great Britain threshold: 595 All-Ireland threshold: 380 GB max: 23,601 Jan NI max: 9,854 Jan Annual Index 2007/08 Previous five-year mean Trend Range 2002/03 - 2006/07 Figure 26.a, Annual indices & trend for Pochard Figure 26.b, Monthly indices for Pochard for GB for GB (above) & NI (below). (above) & NI (below). The annual index for Pochard in Great its preference for relatively shallow water Britain fell to its lowest level ever in (Nilsson 2008). 2007/08, continuing a downward trend that began in 1996/97. A feature of the decline in 2007/08 was the failure of any British sites to qualify as being of international importance for the first time since the relevant thresholds were introduced. The five-year averages for Abberton Reservoir and Ouse Washes both fell by 10%, and of the eight other sites of national importance only Fleet & Wey and Cotswold Water Park (East) experienced what could be described as a relatively good winter for this species. Pochard (Neil Calbrade) The decline experienced in Britain is likely to be attributable to recent mild In Northern Ireland, counts from Loughs winters which have led to an associated Neagh & Beg, the sole remaining site of north-east shift in distribution (e.g. international importance in the UK, again Maclean et al. 2008). For example, numbers showed signs of a small improvement. The have reached record levels in Sweden, peak monthly count increased slightly for where the species has traditionally been the third year in succession to the highest very sensitive to freezing conditions due to level since 2002/03. 83 However numbers are still considerably & Beg have been partly attributed to the short of those present in the 1990s when, effects of eutrophication which may have for example, an exceptional peak of 40,930 reduced the abundance of invertebrates fed was recorded in December 1990. upon by this and some other diving species As well as any climate-induced shift in (Maclean et al. 2007). range, the declines noted at Loughs Neagh 03/04 04/05 05/06 06/07 07/08 Mon Mean Sites of international importance in the UK Loughs Neagh and Beg 7,835 6,764 8,256 8,884 9,023 Jan 8,152 Sites of national importance in Great Britain Abberton Reservoir 5,290 3,188 2,852 3,167 2,355 Sep 3,370 Ouse Washes 3,304 13 2,134 13 1,227 4,197 2,987 Feb 2,770 Loch Leven 2,548 2,193 1,715 3,666 1,650 Nov 2,354 Hornsea Mere 1,325 1,150 1,150 710 650 Feb 997 Dungeness and Rye Bay 980 789 1,053 1,049 728 Aug 920 Chew Valley Lake 480 635 1,580 1,220 600 Dec 903 Fleet and Wey 850 746 682 879 980 Feb 827 Severn Estuary 905 652 760 786 570 Jan 735 Cotswold Water Park (East) 629 410 524 993 884 Dec 688 Loch of Boardhouse 705 770 709 623 441 Nov 650 Sites of all-Ireland importance in Northern Ireland Upper Lough Erne 801 473 329 503 422 Jan 506 Sites no longer meeting table qualifying levels in WeBS-Year 2007/2008 Nene Washes 66 32 88 57 462 Feb 141 Lower Derwent Ings 1,236 39 20 321 103 Jan 344 Brogborough Clay Pit 183 183 Sites below table qualifying levels but exceeding threshold in WeBS-Year 2007/08 in Great Britain Middle Tame Valley Gravel Pits (203) (56) (12) 296 773 Feb 535 Ring-necked Duck Vagrant Aythya collaris Native Range: N America GB max: 3 Nov NI max: 1 Oct Single Ring-necked Ducks were seen at September and October, Lochs Eaval and six sites in England, four in Scotland and Hosta (North Uist) between November and one in Northern Ireland in 2007/08. Long- February, and Foxcote Reservoir between staying birds, some of which are annual November and April. returnees, were at Loch Gelly in July and In Northern Ireland, one was at Lough August, Avonmouth Sewage Works in Foyle in October. Ferruginous Duck Vagrant and escape Aythya nyroca Native Range: N America, Asia GB max: 2 Sep NI max: 0 Ferruginous Ducks were reported from November to be followed by another four sites. In a remarkably similar pattern individual in the spring. of occurrence to the previous year, one was Others were seen at Somersham GP, at Chew Valley Lake between August and Theale GPs and Woodsetts & Owdays Ponds in the period of September to February. 84 Tufted Duck International threshold: 12,000 Aythya fuligula Great Britain threshold: 901 All-Ireland threshold: 370 GB max: 52,004 Feb NI max: 8,893 Jan Annual Index 2007/08 Previous five-year mean Trend Range 2002/03 - 2006/07 Figure 27.a, Annual indices & trend for Tufted Figure 27.b, Monthly indices for Tufted Duck for Duck for GB (above) & NI (below). GB (above) & NI (below). Annual maxima and indices for Tufted Reservoir failed to reach four-figure levels Duck in Great Britain have exhibited very for the first time since 1995/96. A marked shallow increases over the course of the drop was also noted at Hanningfield WeBS indexing period, and 2007/08 saw a Reservoir, although peak counts do have a slight bounce back from the drop in the greater tendency to fluctuate there from index noted in 2006/07. year to year – perhaps as a result of Elsewhere in northern Europe numbers exchange of birds between the site and have increased more significantly in recent Abberton Reservoir nearby. decades, coinciding with the onset of There are no sites of international milder winters (e.g. Nilsson 2008). importance for Tufted Duck in the UK. In Britain, the monthly maximum for Historically, Loughs Neagh & Beg qualified Ouse Washes, where duck numbers of all as such, but in common with other species species are highly dependent on the of diving duck, the site experienced a crash prevailing water levels, was the highest in numbers from 2001/02 onwards. ever. However inland reservoirs fared less Although the rate of decline has slowed in well: the peak count from Rutland Water recent years, the annual maximum in was the lowest since 2001/02 and numbers 2007/08 fell to its lowest ever level since at both Pitsford Reservoir and Walthamstow monitoring of the site began in 1985/86. 03/04 04/05 05/06 06/07 07/08 Mon Mean Sites of national importance in Great Britain Rutland Water 6,818 6,488 8,487 9,758 5,134 Sep 7,337 Loch Leven 3,913 3,826 3,802 3,553 4,140 Oct 3,847 Abberton Reservoir 2,067 5,112 (4,857) 1,187 3,796 Oct 3,404 Ouse Washes 973 13 2,251 13 1,140 13 2,057 3,328 Feb 1,950 Pitsford Reservoir 2,226 2,506 2,066 1,374 774 Sep 1,789 85 03/04 04/05 05/06 06/07 07/08 Mon Mean Walthamstow Reservoirs 1,772 1,771 1,828 1,516 900 Jul 1,557 Hanningfield Reservoir 3,109 400 1,573 2,194 486 Mar 1,552 Staines Reservoirs 1,133 792 2,844 1,865 1,074 Aug 1,542 Chew Valley Lake 1,465 1,235 2,115 1,325 1,480 Sep 1,524 Middle Tame Valley Gravel Pits (325) (129) (64) 1,243 1,766 Sep 1,505 Cotswold Water Park (West) 1,199 960 1,199 1,372 1,343 Feb 1,215 Lee Valley Gravel Pits 1,404 1,222 985 1,215 1,231 Dec 1,211 Grafham Water 815 824 1,337 992 Alton Water 1,440 644 1,063 1,008 664 Dec 964 Sites of all-Ireland importance in Northern Ireland Loughs Neagh and Beg 8,999 9,277 7,871 6,441 6,076 Jan 7,733 Upper Lough Erne 1,236 1,295 1,457 1,478 1,772 Dec 1,448 Lower Lough Erne 580 674 575 705 638 Jan 634 Sites no longer meeting table qualifying levels in WeBS-Year 2007/2008 Hornsea Mere 1,050 900 840 600 565 Oct 791 Wraysbury Gravel Pits 846 1,015 465 429 424 Dec 636 Sites below table qualifying levels but exceeding threshold in WeBS-Year 2007/08 in Great Britain Cotswold Water Park (East) 468 713 522 731 954 Sep 678 Loch of Strathbeg 353 198 448 403 939 Aug 468 13 Draycote Water 1,251 122 1,010 680 928 Nov 798 Sites below table qualifying levels but exceeding threshold in WeBS-Year 2007/08 in Northern Ireland Strangford Lough 203 168 216 (141) 416 Dec 251 Scaup International threshold: 3,100 Aythya marila Great Britain threshold: 76 All-Ireland threshold: 45* GB max: 2,447 Dec NI max: 8,385 Feb Annual Index 2007/08 Previous five-year mean Trend Range 2002/03 - 2006/07 Figure 28.a, Annual indices & trend for Scaup for Figure 28.b, Monthly indices for Scaup for GB GB (above) & NI (below).