Mayhew & Houston 1989; Tamisier &. Pradel; 1992; Brunckhorst & Rösner;. 1998; Mathers et al. 2000) but has received little attention in North Africa,.
51
Diurnal behaviour of wintering Wigeon Anas penel ope at Lac d e s Oiseaux, n or th eas t Algeria M . Hou hamdi & B. Samrao ui
Laboratoire de R e c h e rc h e d e s Z o n e s H u m id e s, University of A n naba , 4 rue Hassi-B e i'da, A nnaba, Algeria. Email: h o u h a m d i m o u s s a @yahoo. fr; b s a m r a o u i@ hotm ail. co m
Over a p erio d of f o u r y ears , th e d iu r n a l b e h a v io u r of W ig e o n A nas p e n e lope w a s m o n i t o r e d at Lac des Oiseaux, a s h a ll o w f r e s h w a t e r lake, p a rt of th e N u m id i a n w e t l a n d c o m p le x located in n o r t h e a s t A lg e ria . W ig eo n a rr iv e a ro u n d late O c t o b e r and o v e r w in t e r f o r 5 -6 m o n t h s , w i t h n u m b e r s f l u c t u a t in g b e tw e e n 200 and 3, 000 birds. Th e y o ccu p y th e c e n t r a l area of th e lake and n o r t h w e s t e r n p a rts d o m in a te d by B u l r u s h S cirpu s la cu stris and Sea C l u b - r u s h S. m a ritim u s , f a r f r o m
any h u m a n
d is tu rb a n c e .
R e s u lts s h o w a s e a s o n a l c h a n g e in b e h a v io u r t h r o u g h o u t t h e s tu d y p e r i od and h i g h l ig h t th e fa c t t h a t fe ed in g fo r m e d an i m p o r t a n t p a r t of th e b ir ds' d iu r n a l a ctivit ie s at Lac des Oiseaux, w h i c h is used bo th as a f e e d ing area and a roost. T h e se r e s u l t s d if fe r f r o m data o b ta in e d in p a r t s of Europe, w h e r e fe e d in g is m a i n ly a n o c t u r n a l activity. P ossib le fa c t o rs i n f lu e n c in g th e g e o g ra p h ic v a ria tio n in th e d iu r n a l b e h a v io u r of W ig eo n are d is cusse d.
Key Words: Anatidae, dabbling ducks, wetlands, tim e budget, w in tering ecology, conser vation, North Africa
The eco logy of W ig eon A nas p e n e lope
has been stu died
inten siv e ly in
received little a tt e n tio n in N o r th Africa, where
lo c a l
w e tla n d s
a re
under
Europe [Owen 1973; C a m p re d o n 1982;
i n c r e a s in g
Pirot et al. 1984; A llo u c h e e t al. 1989;
(Bredin e t al.
M ayhe w & H ou ston 1989; T a m i s ie r &
1992; T a m i s ie r & B o u d o u re s q u e 1994).
P ra del; 1992; B r u n c k h o r s t & R ösner;
A s tu d y of th e b e h a v io u r of Wig eon, one
1998;
of the m o s t a b u n d a n t w a t e r f o w l in the
M athers
et al.
© W ild fo w l & W e tla n d s T rust
2000)
b ut
has
a n th ro p o g e n ic 1986;
pressure
S a m ra o u i
et al.
W ildfow l (2003] 54: 51-62
52 D iu rnal behaviour of w in te ring Wigeon
region, is h e lp f u l in o r d e r to u n d e rs ta n d
c o n tr a s t to th e n e ig h b o u r in g M e k h a d a
th e g e o g ra p h ic v a ria tio n in the w i n t e r
marsh, where
ing s tr a te g ie s of d u c k s and to identify
relatively str o n g .
key e c o lo g ic a l r e q u ir e m e n t s .
W e e k ly
Several
stu d ie s have s h o w n th a t W igeon are
from
h u n tin g
p re s s u re w a s
o b se rva tio n s
O c to b e r
1996 to
w ere
made
O c to b e r 2000
q uite ad a p ta b le and are able to display
t h r o u g h a 20x60 te le s c o p e and a p a ir of
a t r e m e n d o u s p la s tic ity of b e h a v io u r to
10x50
b in o c u la rs .
In d i v id u a l
counts
m a t c h c h a n g in g e n v ir o n m e n t a l c o n d i
w e r e c a rr ie d
t io n s w it h in a sp e cif ic habit a t (Owen &
n u m b e r of W ig eon w a s fe w e r th a n 200.
W i ll ia m s
W hen th is n u m b e r w a s exceeded, an
1976; von K änel 1981). The
out w h e n e v e r the to ta l
lack of data on loca l p o p u la tio n s has
e s tim a t e
c o n s id e r a b ly
achieved by dividing th e flo c k into s m a l l
ham pered
c o n s e rv a t io n
of th e
p o p u la tio n
size w as
eff ort s, and, by exp lo rin g the ecology of
e q u a l p a rts and t h r o u g h e xtra p o la tio n .
Wig eo n, th is p a p e r a im s to f i l l s o m e
The s p a tia l d is t rib u tio n w a s re cord ed
gaps in s c ie n tis ts ' k n o w le d g e of the use
on a m a p and the birds' t i m e bud g e t
of lo cal w e t la n d s by w a t e rf o w l.
( O c t o b e r - A p r il )
was
m on ito re d
fro m
0700h to 0930h and f r o m 12 noon to 1430h.
Methods
These
tw o
periods
were
a s s u m e d to be re p re s e n ta tiv e of a f u l l Data
were
c o ll e c t e d
at
Lac
des
Oiseaux [n o r th e a s t e r n A lgeria), a s h a l low f r e s h w a t e r lake of 75ha d o m in a te d by N a r r o w - l e a f C a tta il Typha an g u stifo tia
and
B u lru s h
S c irp u s
Lacustris
(Figure 1). The s tu d y site is p a rt of the e a s te r n
N u m id i a n
w e t la n d
c o m plex,
w h ic h h old s th r e e R a m s a r sites, Lac des
Ois eaux,
Lac
Tonga
and
Lac
Oubeira, as w e l l as a vari e ty of m a r s h es, dun e s l a c k s and se a s o n a l ponds. Lac Tonga and Lac OubeTra are located w ith in
th e
(Stevenson B é la ir
K ala
et at.
N atio n a l
1988;
com plex
such
as
Lac
P a rk
S a m ra o u i
1998). The w e s t e r n
w e tla n d s ite s
El
includes Fetzara
&
N u m id ia n Ramsar and
the
G u e rb e s -S e n h a d ja w e t la n d s (S am rao ui & B é la ir 1997). D urin g the stu dy period th e lake had not yet b e co m e a p r o t e c t ed
a re a
but
h u nting
was
rare,
in
day, a lt h o u g h
C a m p re d o n
(1981) has
s h o w n th a t W ig eo n may, at tim e s , d is p la y
an
uneven
p a tte rn
of
d iu rn a l
behaviour. A r a n d o m ly s e le c te d fo ca l d u c k ( A ltm a n n 1974·) w a s fo llo w e d fo r 10 m i n u t e s and its b e h a v io u r divided a r b i t r a r il y into five activ ities: feeding, s w im m in g , p reening, s leeping and fly ing.
A d d itio n a l
obse rva tio n s
were
c a rr ie d out at da w n and d u s k to record th e
d u c k 's
m ovem ents
be tw e e n
Lac
des Oiseau x and any o t h e r a d ja c e n t w e tla n d . A data
m atrix
(42 w e e k s /5
activities) w a s a s s e m b le d and analysed u sing
m u l ti v a r i a t e s t a t is t ic a l analysis
w it h th e A D E -4 p a cka g e (T hioulo use et al. 1997). To c o n f i r m
o b s e rv a tio n s
made
at
Lac des Oiseaux, in F e b ru a ry 2002 the tim e
b u d g e t of W igeon at tw o o th e r
sites, th e M e k h a d a , a s e a s o n a l b r a c k ish m a r s h of 15, 000ha, and Lac Tonga,
Diurnal behaviour of w in te ring Wigeon 53
Figure 1. M a p s of L a c d e s Oiseaux, no rthe ast Algeria, s h o w in g the location of w in te ring W ig e o n during 1996-1999.
54- D iurnal behaviour of w in te ring Wigeon
a s h a ll o w f r e s h w a t e r lak e of 2,400ha
bilised f o r s e v e ra l w e e k s before g r a d u
was
all y
m o n ito re d
(A ltm a n n
using
scan
s a m p l in g
1974 ). A to t a l of 45 h o u rs
dw in d lin g
d e p a rt u re
in
off
w ith
m id-M arch.
the
b ir d s '
D ur ing
the
w e re devoted to th e s e l a t t e r o b s e rv a
s tu d y period, W ig eo n oc cu pied th e lake
tions
f o r 6-7 m o n t h s , w it h an average p o p u
at
e ach
si te.
H u n t in g
was
relatively fr e q u e n t t h r o u g h o u t the study
lat ion size of 500 and peaks of aro u n d
period at both sites.
3, 000 birds.
Results
s p a tia l s t r u c t u r e w it h i n th e lake, c o n
W ig eo n displa yed a relatively stable c e n tr a ti n g in the ce n tr e and close to of
n o r t h w e s t e r n p a rt s d o m in a te d by b u l
October, several w e e k s a f t e r th e firs t
rush S. la custris and scattered patches of
w in t e r in g Teal A. crecca (H o u h a m d i &
b ulrush S. maritimus·, two o th e r species,
W igeon
a r r iv e d
at
th e
end
S a m ra o u i 2 0 0 1). A t f i r s t the n u m b e r of
Eurasian Wa te r Milfoil M y riophyllum s p i
bir ds flu c tu a te d , a p rob able ind ic atio n
c a tu m
and
Fennel
of tr a n s ie n t birds on t h e i r w ay f u r t h e r
Potamogeton pectinatus,
s o u th ,
there.
then
th e
population
size
incre ased and th e peak w a s reached
Pondweed also
abo und
M o n i to ri n g th e t i m e b u d g e t d u rin g
d u rin g J a n u a r y (Figure 2). T h e re a ft e r,
the f o u r y e a r period (1996-2000), a to t a l
the n u m b e r decre a s e d s h a rp l y and s t a
of 209 h ours, ind ic ated th a t fe edin g w a s
Figure 2. W eekly co u n t s of W ig e o n at L ac d e s Oiseaux, n ortheast Algeria, for four periods: 1996-1999. Vertical lines are s tan d ard errors.
D iurnal behaviour of w intering Wigeon 55
Figure 3. (a) Pe rce ntage of time allocated by W ige o n at L ac d e s Oiseaux, n o rth e ast Algeria, to diu rna activities ( ^ · sleeping;
WMås w im m in g :
feeding; 1: ::i preening and I
I flying]. Data have beer
ave ra ge d over fo ur w in tering periods, (b) Pe rce ntage of time allocated by W ig e o n to diu rnal feeding al L a c d e s O ise au x for four perio ds: 1996-1999. Vertical lines are stand ard errors. Ie] Pe rce ntage of time allocated by W ig e o n to diu rnal s w im m in g at L ac d e s O ise au x for four periods: 1996-1999. Vertical lines are stand ard errors.
56 D iu rnal behaviour of w in te ring Wigeon
Figure
U.(a)
Pe rce n tage of time allocated by W ig e o n to diu rn al preenin g at L a c d e s Oiseaux, northeas t
Algeria, for four periods: 1996-1999. Vertical lines are sta ndard erro rs. (b) Pe rcentage of time allocated by W ig e o n to diu rn al sle e p in g at L ac d e s O is e au x for four periods: 1996-1999. Vertical lines are sta ndard errors, [c) Perce n tage of time allocated by W ig e o n to diu rn al flying at L a c d e s O ise au x for four periods: 1996-1999. Vertical lines are stan d ard errors.
D iurnal behaviour of w intering Wigeon 57
P r e li m i n a r y
th e m a in activity (55% of t i m e spent), fo llo w e d
by s w i m m i n g
(20%), slee p ing
and
(3%) and
pre enin g
re c o rd e d
at the
(2%)
to c o n f i r m re s u lts o b ta in e d at Lac des
(Figures 3-4). In s h a rp c o n tr a s t to t h e i r
Oiseaux. At both sites, feedin g d o m i
c o u n te rp a rts
in the
nated o t h e r activities, w ith s w i m m i n g
C am a rg u e , W ig eo n at Lac des Oiseaux
and pree n in g being m o r e fr e q u e n t th a n
spent, overall, a n e g lig ib le p a rt of t h e i r
s lee p in g and flying (Figure 5).
th a t
flying
data
M e k h a d a m a r s h and Lac Tonga se e m
o v e rw in te r
t i m e in sleep and fed actively by day. T im e devoted to fee din g increased
The f a c t o ria l p la n e of th e fi r s t tw o axes of th e c o r r e s p o n d e n c e analysis
ste adily t h r o u g h o u t th e w in t e r in g p e r i
(88% of inertia) is s u ffic ie n t to reveal
od, f r o m 45% upon a r r iv a l to n e a rly 60%
th e s t r u c t u r e in th e data by o u tlin in g
p r i o r to th e re t u rn fligh t. P re enin g w as
th e
an i m p o r t a n t activity: the t i m e a llo cate d
b e h a v io u r (Figure 6a). The firs t axis
p ro g re s s iv e
seasonal change
in
to p reening, c a rr ie d out m o s t ly in the
(63% of inertia), w h i c h can be d e e m e d
m o r n in g , r e m a in e d stable th r o u g h o u t
to re p re s e n t th e 'e n e rg y axis' (Figure
th e
6b),
study
p e rio d
S w im m ing
at
aro u n d
20%.
re p re s e n te d , upo n arr ival,
shows
the
c lea r
o p p o s it io n
be tw e e n feeding (actively g ain ing e n e r
27% of d iu r n a l activity before fa llin g to
gy)
a ro u n d 18% f o r the rest of th e w in te r in g
e x p e n d itu re at a m i n i m u m ) w h e r e a s
period. S w i m m i n g w a s g e n e ra lly a s s o
t h e se co n d axis (25% of inertia) h ig h
ciated w it h feeding, and 85% of the
l ig h t s
b ir d s
w ere
r e c o rd e d
feeding
and
s le e p i n g
th e
(k e e p in g
m o n th ly
energy
gradient
w hile
(D e c e m b e r - A p r i l ) th a t s in g le s o u t c o m
s w i m m i n g w h e r e a s 15% w e r e observed
f o r t (and poss ibly c o u rts h ip ) activities
to feed on the n o r t h e r n and n o r t h w e s t
f r o m flying, w h ic h is m o r e p ro n o u n c e d
e rn ba n ks of the lake. T im e a ll o c a te d to
p r i o r to the W ig e o n 's d e p a rt u re f r o m
sleep displayed a p rogressive decline,
th e s tu d y site.
f r o m 10% at th e s t a r t of th e w in te r in g p eriod to 2 -3 % p r i o r to the r e t u r n of the W igeon to t h e i r bree din g g ro u n d s . This l a t t e r a ctivity w a s clea r ly con fined to th e f i r s t pa rt of th e day.
Flight, in f r e
q u e n tly re cord ed and w it h a peak of 4% d u rin g th e f o u r ye a r period, w as m a n i fe st at th e end of the w in t e r in g period and w a s
g e n e r a l ly
p ro voked
by the
p re se n ce of c h ild re n . W igeon w e r e not easily d is tu rb e d by m a r a u d i n g Marsh H a r r i e r Circus aeruginosus and reacted only by flo c k in g in th e c e n tr e of the lake.
58 D iurnal behaviour of w inte ring Wigeon
Figure 6. Plot of factorial plane 1x2 of c o r re s p o n d e n c e an a ly s is of the diu rnal behavio ur of W ig e o n in north e ast Algeria: a] ordination of dates with the cir cles rep re se ntin g the weighted av erage of s a m p lin g w e e k s (sm a ll squ are s]; b] ordination of d iu rn al activities; c] h is to g r a m of eigenvalues.
D iurnal behaviour of w intering Wigeon 59
Discussion
devo ted
la r g e ly to
in t e n s iv e A sizable p ro p o rtio n of W igeon w i n te r
re g u la rly
in
N u m id i a
[ A t k in s o n -
re c o v e ry th r o u g h
f e e d in g
and
p re e n in g .
D e c e m b e r and J a n u a r y see a s u b s t a n tia l inc re a s e in th e t i m e a llo c a te d to
W ille s 19741, w h e r e up to 100, 000 have
s lee p in g
been co un te d . C ounts in re cent years
F e b ru a ry and March th e birds' activ ities
and
s w im m in g ,
have c o n fi r m e d th a t th e region is an
are d o m in a te d by sle e p in g and, once more,
f o r W igeon [I s e n m a n n & M oali 2000).
T a m i s ie r et at. 1995). A n o t h e r fe a tu re
Good
record ed
of the to t a l W igeon
(C am predon
in
i m p o r t a n t w in t e r in g and sta g in g area e s tim a t e s
f e e d in g
whereas
1982;
in the C am a rg u e , s o u th e r n
are
France, is th a t feeding g ro u n d s are d is
unava ila ble, but th e bir d s at Lac des
t i n c t f r o m roosts, m a k i n g up fu n c t io n a l
Oiseaux, Lac Tonga and th e Mekhada
u nits' (T a m is ie r 1985).
p o p u la tio n w in t e r in g
in
N u m id i a
m a r s h p robably a m o u n t to a sizeable
The p a tte rn of b e h a v io u r and use of
fr a c tio n of the to t a l c ou nt (Lac Fetzara
w e t la n d s ob served in N u m id ia are not
is the
f u l ly c o n s i s t e n t w i t h
only o t h e r
m ajor
site
in the
region). The
th e
C am argue
m o d e l but are s i m i l a r to th o s e r e c o r d la te
a rriv a l
of
W igeon
in
ed at Lac Ic hke ul, Tunisia (Bredin et at.
N u m id ia is s i m i l a r to th a t recorded in
1986), w h ic h W igeon exp loit as both a
th e C am a rg u e , but s o m e u n c e rt a in t ie s
d iu r n a l fe eding
s u r r o u n d th e s ta tu s of W igeon th a t w i n
A lth o u g h
t e r in A lg e ria and Tunisia, w h i c h may
h e ig h te n e d f o r m e t h o d o lo g i c a l re a so n s
g ro u n d
th e s e
and a roost.
diffe re n ce s
may
be
d is t in c t fr o m
(scan vs fo cus m e th o d s , s a m p le size,
th a t w in t e r in g in the C a m a rg u e , w ho se
d iu r n a l and n o c t u r n a l o b s e rv a tio n s vs
belong to a pop u la tio n r e p ro d u c t iv e
grounds
are
in S iberia
(T am isie r & D e h o r t e r 1999). U nfo rtu n a te ly, the p re s e n t stu dy did not
include
fo c u s e d
o n ly
co u rtsh ip on
a c ti v it ie s
d iu rn a l
d iu r n a l data), th e p re s e n t s tu d y points t o w a r d s d is tin c t d iu r n a l use s of w e t
and
b e h a v io u r ;
however, W igeo n w e r e s h o w n
not to
devote a sizable p art of t h e i r d iu r n a l
l an d s by W igeon on each side of the M e d ite rr a n e a n . H ow can th e d is c r e p a n c ie s
between
th e s e
patte rn s
be
a c c o u n te d for? It is w o r t h
n o tin g th a t s tu d ie s of
t i m e to c o u r t s h ip (T am isie r & D e h o r te r
t i m e b u d g e ts of W ig eo n w in t e r in g
1999). To o v ercom e the o t h e r l i m i t a
E urope have revealed a w id e va ri a tio n
in
tio n s of th e p re s e n t study, n o c t u r n a l
in th e circ a d ia n p a tt e rn of feeding and
data are needed to a ssess the ove ra ll
s leeping (C a m p re d o n 1982). The s p a
be h a v io u r of W igeon (B a ld a s s a r re et at.
t i o - t e m p o r a l d is t r ib u tio n
1988).
th e C a m a rg u e and e ls e w h e re has been
The w in t e r in g has
been
divided
phases, w it h
s tr a te g y of W igeon
in
a t t r i b u te d to a fixed life t r a it r a t h e r th a n
d is tin c t
a re c e n t a d a p ta tio n to h u n tin g d i s t u r
November
bance [D e h o r t e r & T a m i s ie r 1998). Two
into t h r e e
O cto ber and
obse rved
60 D iurnal behaviour of w in te ring Wigeon
o t h e r reasons, d is t u r b a n c e and visual
of
se le ctio n of food, have been put fo r w a rd
g la s s w o r t
Baudot
R a n u n c u lu s
b a u d o tii and
S alicornia sp.
(C a m p re d o n
to explain the g e o g ra p h ic a l dis cre pancy
1984). W igeon are also able to i n c o r p o
in behaviour. D is tu r b a n c e m ay indeed
rate seed s and a n im a l m a t e r i a l in t h e i r
c o n s tra in d u c k s to s eek safe ty in n u m
diet (C ra m p & S im m o n s 1977; D a n e ll &
bers d u rin g the day in roosts, w h e r e a s
Sjöberg 1982; Jac o b s e n 1991).
th ey m a y d is p e r s e m o r e safely and feed
The W i g e o n ’s s m a l l body size and
by n ig ht w h e n pre d a tio n and hun ting
h e rb iv o ro u s diet are c o n s tr a in t s th a t
p re s s u re s are low.
are m e t by its high food intake and r e l
D is tu r b a n c e by predators , in clu d in g
a tiv e ly
lon g e r
f e e d in g
h u m a n s , u n d o u b te d ly plays an i m p o r
(C a m p r e d o n
ta n t role in the sele ctio n
M a yhew & H ou sto n 1993). In o r d e r to
s i te s
(Owen
&
of feeding
W illia m s
1976).
In
England, fe eding is d iu r n a l in protecte d
1982;
b o u ts
Mayhew
1988;
m e e t its heavy en e rg y r e q u i r e m e n t s , th e
W igeon's
f e e d in g
p la sticity
has
are as and n o c t u r n a l in ha b it a ts e x p e ri
evolved to a ll o w it to graze a ro u n d the
e n c in g
c lo c k (M ayhew
d if f e r e n t
inte n s itie s
of
1988) and in a gre at
d is tu rb a n c e , w h e r e a s both in England
v a ri e ty of h a b it a ts , ra n g in g f r o m f r e s h
and
is
w a t e r lak e s to i n t e r t id a l s a lt m a rs h e s .
in flu e n ce d by the ti m i n g of tid es (Owen
T his p a tt e rn of b e h a v io u r m a y be p a r
&
ti c u la r ly i m p o r t a n t at la titu d e s w h e r e
Fra nce,
Thomas
f e e d in g 1979;
in
von
m u d fla ts Kanel
1981;
C a m p re d o n 1982; M a yh ew 1988). It is
en e rg y r e q u i r e m e n t s
possible th a t the d iu r n a l d is tu rb a n c e
due to lo w e r w i n t e r t e m p e r a tu r e s . The
m a y be
h ig h e r
e n c o u n te r e d by W ig eon in N u m id ia is
t o t a l feedin g t i m e p e r day in N u m id ia
b e lo w a specif ic t h r e s h o ld . Data on th is
a p p e a rs to be m a r k e d l y s h o r t e r th an
a s p ect are needed u rg e n tly as h u m a n
t h a t found e ls e w h e re (12-16 hours), but
e n c r o a c h m e n t is e v e r-in c re a s in g and
fu rth e r
inve stig a tio n s
of
no ctu rn a l
Lac des Oiseaux m i g h t w e l l beco m e
b e h a v io u r of W igeon are needed before
u n s u ita b le f o r w in t e r in g birds.
fa c to rs u n d e rly in g s uch dif fe re n c e s can
The second c o n s tra in t, m a n ife ste d
be a d d re s s e d safely.
in the need to se le c t food visually in a
The w id e g e o g ra p h ic d if fe re n ce in
h e te r o g e n e o u s e n v ir o n m e n t, is linked
the p a tte rn of fe eding and use of w e t
to the W igeon 's diet, w h ic h short
grass
Mayhew
&
swards Houston
inclu d e s
(Owen 1989).
1973; In
th e
lands need not be induced by a single fa ctor, and it s e e m s likely th a t it may re fle ct the i n te ra c tio n of hydrology, p ro
C am a rg u e , the diet of W igeon has been
d u c tiv ity ,
fou nd
pro c e s s e s d if fic u lt to ide n tif y by o b s e r
to be com p o se d , to a sizable
d is t u r b a n c e
a lo n e .
Clea rly,
and more
o th e r
extent, of D itc h g r a s s Ruppia cirrhosa,
vation
d e ta ile d
D w a rf E e lg rass Zostera noltil, Fennel
s tu d ie s are ne eded to u n ra v e l th e f u l l
Pondweed, L e s s e r P ondweed P. p u s il
ra nge of b e h a v io u r d isplay ed by W igeon
lus, E u ra sia n W a te r Milfoil, B u tte rc u p
in N o r th A fric a , and th is e ff o rt s h o u ld
D iu rnal behaviour of w intering Wigeon 61
o b s e rv a tio n
Bunckhorst, H. & Rosner, H-U. 1998. Das
s it e s t h a t h o ld l a r g e r n u m b e r s of b ir d s .
V o rko m m en von Pfeifenten Anas penelope
in c l u d e t h e
use of m o re
im
s c h l e s w ig - h o ls t e in is c h e n
W a tte n -
meer. Corax 1 7 : 81 -96.
Acknowledgements
Campredon, P. 1981. Hivernage du Canard T h e a u t h o r s a r e m o s t g r a t e f u l to Dr. A. T a m i s i e r f o r m a k i n g
h e lp fu l c o m
m e n t s a n d s u g g e s t i o n s w h i c h g r e a t ly im p ro v e d
a
p re v io u s
v e rsio n
of
the
m a n u s c rip t.
References
S if f le u r
en
C a m a rg u e .
France.
Statio nne m en ts et activités. Alauda 49: 169-193. Campredon, P. 1982. Dém ographie et écolo gie du Canard S iffle u r Anas penelope L. pe nd ant son h iv erna ge en France. Docto ral thesis, USTL, M ontp ellier; 161 PP-
Allouche, L., Dervieux, A., Lespinasse, P. &
Campredon P. 1984. Régime a lim en ta ire du
Tamisier, A. 1989. Sélection de l'habitat
Canard S iffle ur Anas penelope L. pendant
diurne pa r trois espèces d'oiseaux d'eau
son hivernage en Camargue. L'Oiseau et la
h e rb iv o re s h iv e rn a n t en C a m argu e [France). Acta Oecotogica/Oecoiogia Applicata 10: 197-212.
RFO 54: 189-200. Cramp, S. & S im m ons, K. E. L. 1977. The
Birds of the Western Palearctic, Vol. 1. Altm an n, J. 1974. Observational study of behaviour: Sam pling m ethods. Behaviour 49: 227-267.
University Press, Oxford. Danell, K. & Sjöberg, K. 1982. Seasonal and diel changes in the feeding behaviour of
A tkin so n-W illes,
G. 1974. The nu m e ric a l
distributio n of ducks, swans and coots as a guide in assessing the im p o rta n c e of w e tlan ds in midwinter. In: Proceedings of
the International Conference on Wetlands and Waterfowl, Peiligenhafen 1974, (ed. M. Smart). Intern atio n al W aterfow l Research Bureau, Slim brid ge; pp. 199-254.
ry:
te c h n iq u e s
for
w a te r fo w l.
t im in g In:
ing
la ke
in
n o r th e r n
Sweden.
Ornis
Scandinavica 13: 129-134. Dehorter, 0. & Tamisier, A. 1998. Hunting v u l n e ra b ilit y and w i n t e r in g s tra te g y am ong w a te rfo w l in Camargue, France.
Wildlife Biology 4: 13-21.
Baldassarre, G.A., Paulus, S. L., Tamisier, A. & Titman, R. D. 1988. W orkshop s u m m a w i n t e r in g
som e dabbling duck species on a breed
activ ity
of
Waterfowl in
H o u h a m d i, M. & S a m ra o u i, B. 2001. Occupation s p a tio -te m p o re lle du Lac des Oiseaux, N o rd-est algérien par l'avifaune aquatique. Alauda 70: 301-310.
Winter, (ed. M. W. Weller). University of Minnesota Press, Min neapolis; pp. 181188.
P. & Moali, A. 2000. Oiseaux dAlgérie. Société d'Etudes Ornithologiques
Isenmann,
de France. Bredin, D., Skinner, J. & Tamisier, A. 1986. D istributio n s p a tio -te m p o re lle et activités
Jacobsen, O.W. 1991. Feeding behaviour of
des Anatidés et foulq ues s u r l'lchkeul,
breeding Wigeon Anas penelope in rela
grand
tio n
q u a rtie r d'hiver tunis ie n.
Etude
pré lim inaire. Acta Oecologica/Oecologica Generalis 7: 55-73.
to
seasonal
s w a r m in g b e h a vio u r Ardea 79: 409-418.
em ergence of
and
c h ir o n o m id s .
62 D iurnal behaviour of w in te ring Wigeon
R. &
Samraoui, B., de Bélair, G. & Benyacoub, S.
Montgomery, W. I. 2000. A study of the im pact of human distu rbance on Wigeon
1992. A m uch threatened lake: Lac des Oiseaux in n o rth e a s te r n Alg eria .
Anas penelope and Brent Geese Branta
Environmental Conservation 19: 264-267,
bernicla
276.
M athers,
R. G., Watson,
hrota
on
S., Stone,
an
Irish
sea
loch.
Wildfowl 51: 67- 81. Mayhew, P.W. 1988. The daily energy intake of
European W ig eon
in winter. Ornis
P.W.
Feeding site
&
Houston ,
D.
C. 1989.
selection by Wigeon
Anas
penelope in relation to water. Ibis 131: 1-8. Mayhew, P.W. & Houston, D. C. 1993. Food th r o u g h p u t tim e
rons, Algeria. An ecological evaluation. Environmental Conservation 15: 335-348.
Scandinavica 19: 217-223. Mayhew,
Stevenson, A . C., Skinner, J. & Smart, M. 1988. The El Kala National Park and envi
in European Wigeon
Tamisier, A. 1985. Some consid eratio ns on the social re q uire m en ts of du cks in w i n ter. Wildfowl 36: 104-108. Tamisier, A.
&
B oudouresque,
C.
1994.
Aquatic bird po pulatio ns as possible in di
Anas penelope and oth er grazing w a t e r
ca to rs
fowl. Wildfowl 44: 174-177.
Ic h k e u l Lake, Tunisia. 279/280: 149-156.
of
se a s o n a l
n u t rie n t
flo w
at
Hydrobiologia
Owen, M. 1973. The w in t e r feeding ecology of Wigeon at B rid g e w a te r Bay, Somerset. Ibis 115: 227-243. Owen, M. & Thomas, G.J. 1979. The feeding
Tamisier, A. & D e ho rte r 0. 1999. Camargue, canards et foulques. Fonctionnement et devenir d'un prestigieux quartier d'hiver. Centre O rnithologique du Gard, Nîmes.
ecology and conservation of Wigeon w i n terin g the Ouse Washes, England. Journal of Applied Ecology 16: 795-809.
Tamisier, A. & Pradel, R. 1992. Analyse s ta tistiq ue de l'habitat hivernal diu rne du Canard
Owen, M. & W illia m s, G. 1976. W in te r d is tr i bu tio n
and
h a b ita t
r e q u ir e m e n ts
of
S if f le u r Anas penelope
C a m argu e.
Persp ectiv e s
de
L.
en
gestion.
Revue d'Ecologie Terre et Vie 47: 135-150.
Wigeon in Britain. Wildfowl 27: 83-90. T am is ier, A., A llo u c h e , Pi rot, J-Y., Chessel, D. & Tamisier, A. 1984. Exploita tion
a l im e n ta ir e
des
zones
hum id e s de Cam argue par 5 espèces de canards de surface en hivernage et en
L., Aubry,
F. &
Dehorter, 0. 1995. W intering strategies and breeding success: hypothesis for a tra d e off in som e w a te r fo w l species. Wildfowl 46: 76-88.
transit: m odélisatio n spatio -tem p orelle . Revue d'Ecologie Terre et Vie 39: 169-192.
Thioulouse, J., Chessel, D., Dolédec, S. & Olivier, J . M. 1997. ADE-4: a m ultivaria te
Samraoui, B. & de Bélair, G. 1997. The Guerbes-Senhadja wetlands. Part I: an
analysis and graphic al display software. Statistics and Computing 7: 75-83.
overview. Ecologie 28: 233-250. Samraoui, B. & de Bélair, G. 1998. Les zones hu m id es de la N um id ie orientale: bilan des conna issan ces et perspectives de gestion. Synthèse 4: 1-90.
von Känel, A. 1981. W in te r feeding ecology of Wigeon Anas penelope at the Ouse Washes, England. Ibis 123: 438-449.
