Freezing conditions and a distinct lack of Bittern; Marsworth CORN BUNTING roost again on the slide

MONDAY 29 NOVEMBER

With the weather currently breaking all manner of records (coldest November night on record at -17.3 degrees at Altnaharra in NW Scotland and the deepest earliest snowfall of 37 inches at Braemar and elsewhere), it is hardly surprising that the 6,000 or so BOHEMIAN WAXWINGS that entered Scotland in late October are moving southbound. More and more are now entering the Three Counties Region, with over 100 recorded today......

WOBURN TOWN (BEDFORDSHIRE)

I joined Matt Andrews, Allan Miller and others this afternoon in Leighton Street enjoying the WAXWING flock now semi-resident there. Once again, they were favouring the Pink Rowans either side of the road in the vicinity of No.10. Numbers present varied during the afternoon but peaked at 42, with just 3 first-years with them. Some 33 were still present mid afternoon but just after a noisy crescendo of trilling, they all flew off together and headed south.

TRING RESERVOIRS (HERTS)

All of the reservoirs are now virtually frozen over, with just three small patches on Wilstone and one small area on Startop's End. There was little of note other than two adult drake Common Goldeneyes on the latter.

I waited until dusk at a bitterly cold Marsworth but failed to see the Bittern again. The reedbed roost attracted just 64 CORN BUNTINGS - another serious decline in numbers.

THE DECLINE IN THE CORN BUNTING REEDBED ROOST AT MARSWORTH RESERVOIR

The Corn Bunting has undergone a dramatic decline in Hertfordshire with an estimated population of 1,000 jangling males in 1985 (J H Terry, Birds in Hertfordshire 1985, 303-312) to just 40 singing males in June 2010 (LGRE et al). The Marsworth Reservoir reedbed has been a traditional roost-site since at least 1970 and a site where I have monitored numbers intermittently since 1973. Many of those figures quoted as maximums below were carried out using my Lynx click-counting machines and should be very accurate whilst others are perhaps best estimates of birds present. The largest count ever made was of 610 birds on 10 December 1983, whilst there have been a few winter counts exceeding 500 birds.

1970: 30 on 31 January: 1971: 22 on 11 February; 1972: 18 on 1 January; 1973: 30+ on 6 January and 100+ on 4 October; 1974: 80 on 4 October; 1975: 55+ on 23 October; 1976: 84 on 1 January; 1977: 62 on 5 February;

1978 - the first year of qualititive counts with up to 450 in the first winter period and 210 in November-December;

1979: just 130 or thereabouts in the first winter period but increasing dramatically to 500 in December;

1980: numbers peaked at around 300 between January and March, with 175 counted on 3 October;

1981: the roost peaked at 320 birds during January to March;

1982: peak counts included 248 on 5 March and 340 on 17 December;

1983: at least 250 roosting in January to March with an incredible 610 reported on 10 December;

1984: In the region of 340 counted in the first winter period and 310 in the second;

1985: Just 200 birds counted in both winter periods;

1986: Again 200 was the mean figure throughout both periods;

1987: the only count recorded was of 60 birds on 22 February;

1988: Again, 60 birds was about the norm during both winter periods;

1989: 165 counted during December;

1990: up to 70 in the first period, with 230 in December;

1991: peak counts included 343 on 26 January and 300 in December;

1992: remaining stable with 300 on 24 January and 324 on 31 October;

1993: respective counts of 230 in January and 220 on 27 December;

1994: numbers fluctuated between 230 and 250 in January-March but declined to just 70 in December;

1995: 150 on 13 January was followed by a peak autumn count of 195 on 8 December;

1996: a marked decline in numbers with no roost count exceeding 90 birds;

1997: an improvement in fortunes with 120 in November to December;

1998: the peak count was of 160 on 30 January;

1999: an improving picture with 210 on 11 February and 200 on 5 December;

2000: numbers peaked at 167 on 2 February and 80 on 31 December;

2001: 125 roosted during February, with 88 in December;

2002: a peak of 97 on 2 January and 80 on 16 December;

2003: 135 were counted on 7 January with 100 on 31 December;

2004: 133 on 25 February was the peak annual count;

2005: 156 on 4 February and 140 on 14 December;

2006: a peak of 196 on 25 January

2007: peak counts included 148 on 20 January and 178 on 16 December;

2008: 159 on 25 January was my peak count, with 164 on 14 December;

2009: 127 on 8 January and just 86 on 20 December.