Lesser Black-backed Gull- Kleine Mantelmeeuw (graellsii & intermedius)

(last update: January 31 2013)

Home

LBBG rings

lbbg 1cy May
lbbg 1cy June
lbbg 1cy July
lbbg 1cy August
lbbg 1cy September
lbbg 1cy October
lbbg 1cy Nov - Dec

lbbg 2cy Jan-Febr
lbbg 2cy Mar-April
lbbg 2cy May
lbbg 2cy June
lbbg 2cy July
lbbg 2cy August
lbbg 2cy September
lbbg 2cy October
lbbg 2cy Nov - Dec

lbbg 3cy Jan-April
lbbg 3cy May
lbbg 3cy June
lbbg 3cy July
lbbg 3cy August
lbbg 3cy September
lbbg 3cy October
lbbg 3cy Nov - Dec

lbbg sub-ad Jan-April
lbbg sub-ad May
lbbg sub-ad June
lbbg sub-ad July
lbbg sub-ad Aug
lbbg sub-ad Sept
lbbg sub-ad Oct
lbbg sub-ad Nov - Dec

lbbg ad January
lbbg adult February
lbbg adult Mar-April
lbbg adult May
lbbg adult June
lbbg adult July
lbbg ad August
lbbg ad September
lbbg ad October
lbbg ad Nov - Dec

adult: July

By July, most adult Lesser Black-backed Gulls are very busy feeding the now fledged young. By mid-July large flocks of 100's of 1cy birds leave the colonies simultaneously and gather on the sandy beaches. The adults keep on feeding the 1cy birds on these beaches, often until the end of the month. 
The moult score on adult LBBG may be influenced by the energy and effort which is put in the feeding of chicks. In the colony, we try to score primary and wing-covert moult in relation with number of eggs or fledged chicks. Year 2002 we didn't collect enough data on this subject. However, we can represent figures of primary moult in adult LBBG which still have a strong bond with the colony. They arrive at a nearby sandy beach to drink, wash and preen quickly, leaving again within 10 minutes to fly back into the colony. Primary moult score is presented in the next table.

 

Tables & Graph

starting date:   25 Jun   02 Jul   09 Jul   30 Jul   06 Aug
week no: 26 27 28 31 32
REM 0 0 0 0 0 0
REM 1 0 0 0 0 0
REM 2 0 0 0 0 0
REM 3 0 0 0 0 0
REM 4 0 0 0 4 0
REM 5 0 0 0 7 1
REM 6 0 1 0 13 12
REM 7 0 14 10 16 6
REM 8 0 64 53 13 3
REM 9 1 112 84 1 3
REM 10 5 127 140 10 1
0 0 0 0  
n = 6 318 287 64 26
average P = 9.8 9.1 9.2 7.1 6.9
95% CID = 0.43 0.10 0.10 0.43 0.51
inverse = 2.57 1.97 1.97 2.00 2.06
Variantie (s2) = 0.17 0.80 0.76 2.91 1.59
SD (s) = 0.41 0.89 0.87 1.71 1.26
SE (sx) = 0.17 0.05 0.05 0.21 0.25
           
% class:          
0 0 0 0 0 0
1 0 0 0 0 0
2 0 0 0 0 0
3 0 0 0 0 0
4 0 0 0 6 0
5 0 0 0 11 4
6 0 0 0 20 46
7 0 4 3 25 23
8 0 20 18 20 12
9 17 35 29 2 12
10 83 40 49 16 4
           
  % control: 100 100 100 100 100

Table above, data for the Netherlands (2000-2010), results for July (aggregated week): number of remaining old primaries in adults.
REM10 = 10 primaries still old (hence, complete moult not started yet).

Above: Scatter Plot for PMS in adult Lesser Black-backed Gulls. Number of remaining old primaries throughout the year (arrested moult excluded). Sample size is 6.171 birds.

Above: Scatter Plot for PMS in adult Lesser Black-backed Gulls. Number of remaining old primaries for July (arrested moult excluded). Sample size for this graph is 302 ringed birds + 399 unringed birds.

starting date:

04 Jun

02 Jul

09 Jul

13 Aug

week no:

23

27

28

33

NEW 0

8

1

115

3

NEW P1

0

1

6

2

NEW P2

0

0

0

6

NEW P3

0

0

0

7

NEW P4

0

0

0

8

NEW P5

0

0

0

1

NEW P6

0

0

0

0

NEW P7

0

0

0

0

NEW P8

0

0

0

0

NEW P9

0

0

0

0

NEW P10

0

 

 

 

 

 

 

 

 

n =

8

2

121

27

average NEW P =

0.0

0.5

0.0

2.7

95% CID =

0.00

6.35

0.04

0.55

inverse  =

2.36

12.71

1.98

2.06

Variantie (s2) =

0.00

0.50

0.05

1.92

SD (s) =

0.00

0.71

0.22

1.39

SE (sx) =

0.00

0.50

0.02

0.27

 

 

 

 

 

% class

 

 

 

 

0

100

50

95

11

1

0

50

5

7

2

0

0

0

22

3

0

0

0

26

4

0

0

0

30

5

0

0

0

4

6

0

0

0

0

7

0

0

0

0

8

0

0

0

0

9

0

0

0

0

10

0

0

0

0

 

 

 

 

 

% control:

100

100

100

100

  Table above, data for the Netherlands (2000-2010), results for July (aggregated week): number of new, fully grown primaries in adults.
NEW0 = no new primaries visible (arrested moult excluded in this analysis). So either P1 still old, or P1 dropped, but the very tip still not visible.
NEW1 = P1 longest new primary. Range between "at least the tip of P1 is visible" until "tip of P2 still shorter than P1".
NEW2 = P2 longest new primary. NEW3 = etc.

Above: Scatter Plot for PMS in adult Lesser Black-backed Gulls throughout the year. Longest new primary is classified "fully grown". Sample size is 2.969 birds. Birds scored on NEW primaries (arrested moult excluded).

Above: Scatter Plot for PMS in adult Lesser Black-backed Gulls. Scoring on longest new primary, which is classified "fully grown" for July (arrested moult excluded). Sample size for this graph is 2 ringed birds + 121 unringed birds.

The earliest date for birds with missing primaries is 30 April 2006, which is not the earliest day in our complete sample. We scored 98 Lesser Black-backed Gulls prior to that date, some already in February. As can be expected, none of these was in primary moult, and this group was excluded in our further analysis as it will only result in a misfit for the onset of moult, using linear regression statistics.

The last scoring days were in November, with a larger sample (133 adults) on 04 November 2010. From that date we have the last birds with retaining old primaries (13 birds with 1, 2 or even 3 old primaries; 120 birds with no old primaries left). From other days in November, only 10 birds were scored (all ringed adults). They all had no old primaries left.

The first tine a new primary (P1) was visible, was on 08 May 2006. Prior to this date, birds were scored missing inner primaries, but the very tip was still not visible (and therefore not scored). As soon as the tip of P1 was visible, this was automatically scored "fully grown" For the other primaries to be scored fully grown, they had to exceed the previous primary in length (so P2 fully grown, only from when it is longer than P1).

Peter Stewart presents onset of primary moult by scores for caught adult Lesser Black-backed Gulls in the Severn Estuary, U.K., repeated in the table below. To read his results, see this PDF file.  

Table: the number of old remaining primaries present. Compare PMS of adult graellsii at half monthly intervals. Data from the Severn Estuary Gull Group by Peter Stewart: The primary moult of the Lesser Black-backed Gull (special publication No 1). Scores in the Netherlands can be influenced by unringed nominate fuscus, in autumn in particular.

 

Netherlands

Severn Estuary U.K.

 

PMS range

N:

Average PMS

PMS range

N:

Average PMS

1-15 apr

10

49

10

8-10

216

9,9

16-30 apr

10

47

10

10

197

10,0

1-15 may

8-10

849

9,8

8-10

167

9,9

16-31 may

7-10

380

9,7

7-10

76

9,5

1-15 jun

8-10

104

9,6

7-10

33

8,6

16-30 jun
7-10
253
9,7
6-10
65
8,2
1-15 jul
6-10
605
9,2
5-10
176
7,4
16-31 jul
-
-
-
4-8
44
6,4
1-15 aug
3-10
143
6,6
3-10
165
5,2
16-31 aug
2-10
1284
5,4
3-8
127
4,6
1-15 sep
1-10
300
3,6
0-7
234
3,3
16-30 sep
0-7
645
2,9
0-7
173
2,1
1-15 oct
0-9
733
2,2
0-4
328
0,9
16-31 oct
0-10
750
1,3
0-3
244
0,3
1-15 nov
0-3
138
0,2
0-3
604
0,1
16-30 nov
0
5
0
0-1
341
0,0

LINEAR REGRESSION

Onset of primary moult can best be illustrated by a sinusoid for the first few weeks and last weeks, but there appears to be linear dependency over much of the central moult period.

LINEAR REGRESSION FOR OLD REMAINING PRIMARIES

Complete sample: Linear regression (n = 6171, R2= 0.820, sign: P<0,000)
PMS = -0,381* WEEK + 17,967

Ringed adults: Linear regression (n = 2069, R2= 0.800, sign: P<0,000)
PMS = -0,325* WEEK + 16,270

Unringed adult: Linear regression (n = 4102, R2= 0.779, sign: P<0,000)
PMS = -0,513* WEEK + 23,031

LINEAR REGRESSION FOR NEW FULLY GROWN PRIMARIES

Complete sample: Linear regression (n = 2969, R2= 0.930, sign: P<0,000)
PMS = 0,302* WEEK - 5,933

Ringed adults: Linear regression (n = 1209, R2= 0.888, sign: P<0,000)
PMS = 0,252* WEEK - 4,747

Unringed adult: Linear regression (n = 1760, R2= 0.833, sign: P<0,000)
PMS = 0,442* WEEK - 11,906

 

Primary moult score of adult LBBG at Maasvlakte, the Netherlands, July.
  Missouriweg 13.07.02 Dintelhaven 14.07.02
0 missing:  34 62
P1 missing:  27 39
P2 missing:  14 18(1)
P3 missing:  2 2
P4 missing:  0 0
n:  77 121
(1): Five birds had P2 missing and P1 growing.
Missouriweg: aggregate score from location Nachtegalenkeet & Missouriweg - Maasvlakte, the Netherlands (51.57N,04.03E).
Dintelhaven: score from
location Dintelhaven - Maasvlakte, the Netherlands (51.57N,04.03E). See Maasvlakte map.

Some details about colour rings (CRs)

Late June, early July are the weeks to catch pulls and colour ring them. This has been done for years now at Maasvlakte, the Netherlands and most images show ringed adults from these projects. Ring projects are going on for decades already and in Vest-Agder, S Norway, over 60.000 LBBGs have been ringed throughout the years. From 1995 on, blue colour ringed LBBGs from Scandinavia turn up. Some details:

 

species: intermedius intermedius intermedius fuscus fuscus
age: 1cy 5cy+ Pull 1cy Pull
total:
1
81
4390
1
10
<>
.
.
.
.
1985
.
.
2
.
.
1986
.
.
1
.
.
1988
.
.
.
.
1989
.
.
1
.
.
1991
.
.
4
.
.
1993
.
.
1
.
.
1995
.
.
84
.
.
1996
.
.
117
.
.
1997
.
.
726
.
.
1998
.
.
439
.
.
1999
.
19
843
.
.
2000
1
3
454
1
10
2001
.
59
1718
.
.

 

At Westkapelle, the Netherlands (see distribution), LBBGs can be found well into November. Readings of (metal) ringed LBBGs revealed some originate  from Denmark, some from Sweden and some from S Norway. Although local Dutch individuals may occur as well, bulk of the present LBBGs in November are probably Scandinavian birds. Large colonies can be found in Vest Agder (S Norway) and this is the most northern colony from which ringed Scandinavian birds occur in the Netherlands. 

But though they may be seen in NW Europe well into November, others (from the same colony) proved to be more adventurous. For instance this known long distance migrant, much in line with Finnish colour-ringed LBBG fuscus. It's a 1cy LBBG X, metal ringed Stavanger 472418 date July 5 1984 at Rauna, Farsund, Vest-Agder, Norway 58.03N 06.40E and shot October 18 1984 in Owando, Kongo 00.27S 15.44E, 6553 km to the south 3 months and 13 days later.
Colour-ringed birds from the Maasvlakte have been reported to migrate over long distances as well: they were seen at interesting location e.g. USA and Finland.

In the Ring Recovery Section, we try to plot the races of Larus fuscus to give more detials on the various migration routes.

ad LBBG UK.:
graellsii
adult LBBG Dutch intergrade in September, ringed in the Netherlands. (85708 bytes)LBBG adult 1N8B July 27 2013, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 19cy & 21cy BTO GG49760 2012 & 2014, Calais, NW France. Picture: Jean-Michel Sauvage.
ad LBBG France:
graellsii
Lesser Black-backed Gull 5cy-6cy 028A July 06 2014, Calais, NW France. Picture: Jean-Michel Sauvage. Also August 2013, when showing arrested moult.
Lesser Black-backed Gull 5cy 029A May 18 & July 04 2013, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 6cy 142N July 27 2010, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 8cy FRP EA639885 / 165N April 15-24 2011 & July 18 2012, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 6cy & 9cy FRP EA670004 / 169N July 2010 & March 2013, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 8cy FRP EA639851 / 192N August 2009, April & July 2012, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 7cy 280N July 18 2012, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 2cy, 6cy-9cy 359N April 2011-2014, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 7cy 589N July 12 2013, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 4cy-6cy 600N 2010-2012, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 6cy 718N July 04 2013, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 5cy FRP EA676223 / 826N July 17 2012, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 6cy 883N April & July 2013, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 4cy-5cy 963N May 2011 & April 2012, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 5CY, 8CY-9CY 989N 2010, 2013 & 2014, Calais, NW France. Picture: Jean-Michel Sauvage.
ad LBBG Belgium:
graellsii Dutch intergrade
ad LBBG in October, ringed in the Netherlands. (60900 bytes)Dutch intergrade DWAH July 31 2010, Neeltje Jans, the Netherlands. Female.
ad LBBG in October, ringed in the Netherlands. (60900 bytes)Dutch intergrade GRAR July 03 2010, Heemskerk, the Netherlands. Female, also as 7cy.
Lesser Black-backed Gull 7cy HCAA July 05 2014, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 5cy HKAB 2012 & 2013, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 6cy KJAM June & July 2013, Calais, NW France. Picture: Jean-Michel Sauvage.
adult LBBG Dutch intergrade in September, ringed in the Netherlands. (85708 bytes)LBBG 4cy NHAH July 20 2013, Calais, NW France. Picture: Jean-Michel Sauvage.
Lesser Black-backed Gull 11cy BLB L-63883 July 29 2011, Calais, NW France. Picture: Jean-Michel Sauvage.
2433arnhem.jpg (52667 bytes)adult LBBG BLB L-10321x July 27 2010, Neeltje Jans, the Netherlands.
Lesser Black-backed Gull 6-8cy BLB L906179 2010-2012, Calais, NW France. Picture: Jean-Michel Sauvage.
2433arnhem.jpg (52667 bytes)adult LBBG BLB L-909103 July 27 2010, Neeltje Jans, the Netherlands.
2433arnhem.jpg (52667 bytes)adult LBBG BLB L-910478 July 31 2010, Neeltje Jans, the Netherlands.
ad LBBG the Netherlands:
graellsii Dutch intergrade
adult LBBG in June, ringed in the Netherlands. (57378 bytes)8+cy LBBG FADZ July 16 2011, Texel, the Netherlands. Ringed as breeding female.
LBBG MAAJ July 25 2010, Texel, the Netherlands.
LBBG MABH July 22 2012, Texel, the Netherlands.
Lesser Black-backed Gull 6cy-8cy OV 2010-2012, Calais, NW France. Picture: Jean-Michel Sauvage.
LBBG 0M July 27 2010, Neeltje Jans, the Netherlands.
LBBG 0N July 21 2010, Neeltje Jans, the Netherlands.
LBBG 7CY CY July 05 2014, Calais, NW France. Picture: Jean-Michel Sauvage.
LBBG GN July 16 2012, Utrecht, the Netherlands. Picture: Herman Bouman.
adult LBBG P July 7 2001, IJmuiden, the Netherlands. Ringed at IJmuiden, white left double black top and red right P.
adult LBBG, July 7 2001, IJmuiden, the Netherlands. Ringed at IJmuiden.
5293.jpg (75893 bytes) adult LBBG T July 7 2001, IJmuiden, the Netherlands. Ringed at IJmuiden, white left triple black bar and red right T.
2433arnhem.jpg (52667 bytes)12cy LBBG TN1 July 21 2009, Barneveld, The Netherlands. Picture: Herman Bouman.
2407n129.jpg (56792 bytes) adult LBBG N129 July 14 2002, Papegaaienbek, Maasvlakte, the Netherlands.
adult LBBG in June, ringed in the Netherlands. (70789 bytes)9cy LBBG EM30 July 13 2004, Missouriweg, Maasvlakte, the Netherlands. Ringed as pullus July 10 1996.
2431as2.jpg (60528 bytes) 11cy LBBG AS2 July 14 2002, Papegaaienbek, Maasvlakte, the Netherlands. Ringed as pullus on June 20 1992.
5157.jpg (59991 bytes) 9cy LBBG EK3 July 06 2001, IJmuiden, the Netherlands. Ringed left green EK3 on June 21 1993 at Maasvlakte.
5156.jpg (31113 bytes) 5cy LBBG PC7 July 06 2001, IJmuiden, the Netherlands. Ringed left green PC7 on July 01 1997 at Maasvlakte.
2287.jpg (75119 bytes) 6cy LBBG PP4 July 14 2002, Dintelhaven, Maasvlakte, the Netherlands. P1 is still present. Ringed as pullus on June 28 1997.
5313.jpg (49220 bytes) 5cy LBBG SR6 July 07 2001, IJmuiden, the Netherlands. Ringed left green SR6 on July 01 1997 at Maasvlakte.
2276.jpg (36510 bytes) adult LBBG TV4 July 14 2002, Dintelhaven, Maasvlakte, the Netherlands. P1 is still present.
2290.jpg (37578 bytes) 8cy LBBG E495 July 14 2002, Dintelhaven, Maasvlakte, the Netherlands. Ringed as pullus on June 29 1995.
2272.jpg (91297 bytes) 6cy LBBG EAH9 July 14 2002, Dintelhaven, Maasvlakte, the Netherlands. P3 has been shed. Ringed as pullus on June 24 1997.
2433arnhem.jpg (52667 bytes)adult LBBG NLA 5.412.028 July 31 2010, Leiden, the Netherlands.
LBBG 6cy NLA 5.421.834 July 17 2012, Calais, NW France. Picture: Jean-Michel Sauvage.
2433arnhem.jpg (52667 bytes)adult LBBG NLA 5.331.913 July 14 2002, Papegaaienbek, Maasvlakte, the Netherlands.
2279.jpg (48429 bytes)adult LBBG NLA 5.293.8?? July 14 2002, Dintelhaven, Maasvlakte, the Netherlands. P1 and P2 have been shed.
 
unringed adult LBBG
 
LBBG adult, July 18 2013, Katwijk, the Netherlands. P1-P10 present.
LBBG adult, July 18 2013, Katwijk, the Netherlands. P1-P10 present.
LBBG adult, July 18 2013, Katwijk, the Netherlands. P1-P10 present.
LBBG adult, July 18 2013, Katwijk, the Netherlands. P1/P3.
LBBG adult, July 18 2013, Katwijk, the Netherlands. P1/P3.
LBBG adult, July 18 2013, Katwijk, the Netherlands. P1/P4.
LBBG adult, July 18 2013, Katwijk, the Netherlands. P2/P5.