WeBS Counts and Warbler Survey

Up-dated MARCH 2004

Wildfowl counts for early 2004 will take place on 25th January, 22nd February, 21st March and 25th April. Help is always most appreciated. Meet at car park adjacent to No3 bed at 08 30h.

                                                                WeBS Counts 2003   

  In mid-August,  297 Gadwall were counted on the Reserve; this is almost certainly a County record.        

**March recordings also included a Ringed Plover, Dunlin, 2 Redshank and 2 Kingfisher. A male Garganey was seen on the river during the April count. At the September count, a Jack Snipe was  seen at the sandpit pond:

   3 Black-tailed Godwit were noted during September and November counts.

#  Single sightings of Goosander and Kingfisher also noted

from 1998 – 2002 

Monthly wildfowl (WeBS) counts have been carried out at Woolston since late 1978 and all the data is held by the WeBS Secretariat at Slimbridge.  Listed below are the species that occur regularly in nationally important numbers at the site. 

The qualifying levels for national importance are as follows: 

                Gadwall  80 

                Teal   1400 

                Shoveler   100

                 Pochard   440 

                 Tufted Duck   600 

NB  

a)      The qualifying level for international importance for Teal is 4000 and this was reached during January       2002.  In the past flocks of up to 5,500 have occurred in winter at Woolston, but ca 2000 is a more         typical winter maximum.

b)      Although the Tufted Duck five-year mean does not reach the national importance level in the above table a flock of 858 was present early in 2003 and if one was to calculate a five-year mean for 1999-2003 this would be 628, thus exceeding the qualifying level of 600. 

2.      Breeding Waterfowl 

2.1    Black-necked Grebe 

Woolston Eyes is the principal breeding site in the country for this rare grebe (less than 50 breeding pairs in the United Kingdom).  It was first recorded at Woolston in the mid 1980s and breeding first proved in 1987.  At least one pair summered in 1988 and two young were seen, while in 1989 five adults summered and two pairs bred.  In 1990 similar numbers were present and three broods hatched.  In 1991 eleven adults summered and four pairs bred, all of which double brooded. 

However, late in 1991 the landowners (The Manchester Ship Canal Company) drained the breeding water on the ground of public safety, claiming that the surrounding earth bunds were unsafe in various places.  With most of the water gone a few Black-necked Grebes returned each spring from 1992 – 1994 but did not stay long.  Several pairs bred at three other sites in North Cheshire and Greater Manchester in those years. 

By 1995, however, following a wet winter the water level rose on the former breeding site at Woolston (No. 3 bed) and two pairs bred, fledging three young.  In 1996 three pairs bred, although only one young fledged, whilst in 1997 four pairs bred (the maximum number of adults was nine) and four young fledged.  Since then numbers have increased dramatically as the following table shows: 

 The poor breeding success in 2002 was almost certainly the result of very cold and wet weather when broods were appearing. 

2.2    The importance of Woolston Eyes for Black-necked Grebes

For a paper to be published in ‘British Birds’ of which I am co-author I have been allowed access to all the data held on Black-necked Grebes by the Rare Breeding Bird Panel since its inception in 1973.  It is clear from this that Woolston Eyes is now by far the most important breeding site for this rare grebe in the United Kingdom.  The Panel’s latest published report is for the year 2000 and at that time Woolston was supporting 20 – 25% of the national breeding population.  This proportion has since increased and from the information available to me it is likely that in 2002 this reached at least 40%.  The 52 adults present is the highest count ever at a breeding site in the United Kingdom.

For more detailed information on the development of the Black-necked Grebe colony at Woolston Eyes see: B. Martin – The History of Black-necked Grebes at Woolston Eyes, Cheshire and Wirral Ornithological Society Annual Report, 2001. 

2.3    Breeding Wildfowl (main species). 

Numbers of  broods seen 

NB.  2002 was a poor year for many waterfowl at Woolston, almost certainly the result of cold, wet and windy weather for long periods in mid-summer.  Only Mallard, which breed relatively early, fared reasonably well.  Terrapins have, however, been present in increasing numbers, but their effect, if any, is at present unknown.

 Ruddy Duck numbers have steadily declined since 1999, no doubt as a result of the cull.  In the early 1990’s Woolston was considered to be the main breeding site in the United Kingdom for this controversial duck. (see species account in the 1988 – 1991 Breeding Bird Atlas). 

 It is important to place the data in the above table in  national and regional contexts.  The Pochard and Gadwall breeding numbers are particularly significant.  In the case of  Pochard the Breeding Bird Atlas estimated the national population at 400 pairs in 1991, while the latest report of the Rare Breeding Bird Panel (published in ‘British Birds’ in November 2002) gives the national population in 2000 as a maximum of 545 pairs, 71 of which were in northern England.  Woolston Eyes was thus supporting 3.6% of all the breeding Pochard in the United Kingdom in 2000 and 28% of the north of England population. 

The RBBP Report for 2000 indicates the United Kingdom Gadwall population as about 1000 pairs, 123 of which were found in northern England.  Thus Woolston had just over two per cent of the national breeding population and 17% of the north of England breeding numbers.  In reality all the figures in the above table should be regarded as an absolute minimum for by making the assessments on broods only, it ignores pairs that were present but which failed, or pairs whose broods were missed in the thick reed cover on the main breeding waters.    It is known, for example, that in spring 2000 a minimum of 25 pairs of Gadwall was present on No.3 bed alone, and as many as 50 pairs on the site as a whole.

The Tufted Duck breeding population , although not of national significance, is certainly of regional importance, with over half of the broods seen in Cheshire in 2001 (25 out of 48) being at Woolston. 

The vast majority of Gadwall, Pochard and Tufted Duck breed on No. 3 bed, as do the Black-necked Grebes.

Brian Martin May, 2003

The 2004 warbler survey is scheduled for Sunday May 16th, commencing at 0430h

                                                            Warbler Survey  2003

 

Beds	No 1	No 2	No.3	No.4	TOTALS
Grasshopper Warbler	2	-	2	3	7
Sedge Warbler	8	8	11	77	104
Reed Warbler	17	1	18	5	41
Whitethroat	2	23	25	33	83
Lesser Whitethroat	-	-	1	-	1
Garden Warbler	3	2	2	-	7
Blackcap	5	7	12	8	32
Chiffchaff	14	9	12	9	44
Willow Warbler	25	8	18	28	79
Reed Bunting	14	4	6	15	39

                                                         Warbler Survey 2002 

* Not Visited

It was unfortunate,  that  on the beautiful spring morning (May 12th)  scheduled for the 2002 Warbler count, a lack of availability of personnel resulted  in a  somewhat restricted survey. Only No.4 bed was completely surveyed. Approximately two- thirds of No.3 Bed was covered (though  not the important north bank)  and only the outer banks of No.2 Bed  No. 1 Bed was not visited at all. 

As so much of the Reserve was not covered  the totals are somewhat meaningless. However, the data suggests that if the Whitethroat figures were extrapolated to the whole reserve, record numbers were present (cf. figures for previous 2 years,151 and 169 in 2000 which was the highest count to date). 

                               Warbler Survey 2001

 

Beds	No1 Bed	No2 Bed	No3  Bed	No 4 Bed	Totals
Blackcap	10	19	16	14	59
Chiffchaff	6	6	5	5	22
Garden Warbler	1	0	1	1	3
Grasshopper Warbler	7	4	1	4	16
Lesser Whitethroat	0	0	0	0	0
Reed Warbler	9	33	30	11	83
Sedge Warbler	15	31	40	112	196
Whitethroat	13	37	24	77	151
Willow Warbler	23	21	24	33	91
TOTALS	84	151	140	247	621
Reed Bunting*	19	17	15	21	72

*Appended

As always the date of the count is significant and this year was one of the latest. This almost certainly accounts for the lowest Sedge Warbler count for many years since some birds had settled to breed and had stopped singing. The same may apply to Willow Warblers. The Reed Warbler count is the highest count ever but again the date of the count could be a contributing factor since they continue to arrive into June. Even so the increasing area of phragmites have certainly attracted more to the Reserve which could now hold in excess of 100 pairs.

The Blackcap total is interesting in that for the last four years it has been 59!

Grasshopper Warbler numbers continue their high recent level and since the count more have been heard reeling in areas where they were not heard on the 19th so we could have record levels this year.