Anas crecca - sexing autumn and spring

Eurasian Teal

SEXING:

 

Male:

  • Unmistakable when in breeding plumage (c. Nov to Jul). From Sep, although most males will still be in eclipse or post-juv (eclipse-like) plumage, careful examination of the body plumage often reveals some colourful breeding feathers on the rump, flanks, back or head.
  • An examination of the cloaca is also diagnostic, males having a penis while females do not. Juv males show a much-reduced penis until c. Dec, making this character useful for ageing too. Cloacal examination requires careful handling and practice.
  • Extensive iridescent green speculum (3 to 6 iridescent green secondaries). If 5 or more SS are mostly iridescent green on the outer vane, the bird is a male.
  • Other characters (distal white margin to SS, design of T1, fringing in TC LC and MC, colour of outer GC and spotting in bill) are discussed in the images below. Beware that these characters are subject to much variation and should not be used in isolation.

Female:

  • Dull-brown plumage. Beware that males in eclipse plumage and post-juv plumage superficially look very similar to females.
  • Lack of penis. Without experience, penises can be difficult to bring out, potentially leading one to believe that there is an absence of it. Cloacal examination requires careful handling and practice.
  • Typically, reduced iridescent green speculum (1 to 4 iridescent green SS). If 2 or less SS are mostly iridescent green on the outer vane, the bird is a female.
  • Other characters (distal white margin to SS, design of T1, fringing in TC LC and MC, colour of outer GC and spotting in bill) are discussed in the images below. Beware that these characters are subject to much variation and should not be used in isolation.

Male (2cy+), May. Unmistakable when in breeding plumage (c. Nov to Jul). Eclipse plumage is acquired starting around Jun, and from that point onward sexing is not as simple. [7066194]

Female (2cy+), June. Dull-brown plumage. Beware that males in eclipse or post-juv plumage (c. Jun to Oct) superficially look very similar to females. [6432318]

Male (1cy), October. The single vermiculated body feather betrays this individual as a male. [6A00050]

Male (2cy+), September. Starting to show green and brick-red feathers in the head. [7066263]

Male (1cy), September. Two vermiculated feathers in the rear flank. [6A00021]

Male (1cy), October. No breeding body feathers visible, sex determined through other criteria. [6A00051]

Male 2cy+, October. Males can either have a long and wide penis that is folded inside a membrane (ad), or a small and narrow penis whose entire length can be visible (young). See Ageing in autumn for more details. Beware of cloacal parasites which can give the appearance of a penis at first glance. [6A00050]

Female 2cy+, October. Absence of a penis is always diagnostic of a female. Beware that without experience penises can be difficult to bring out, potentially leading one to believe that there is an absence of it.[6A00049]

Male (1cy), November. Showing an extensive speculum (5 iridescent green SS). Also, secondaries show narrow distal white margin. [6A00021]

Male (1cy), September. Variation. A fairly reduced speculum for a male (3 iridescent green SS). [6429427]

Female (2cy+), September. Showing a reduced speculum (2 iridescent green SS). Also, SS show broad distal white margin. [6432678]

Female (2cy+), September. Variation. A fairly extensive speculum for a female (4 iridescent green SS). [6456814]

Male 2cy+, October. Deep-black band in T1, edged by a pearly grey. TC grey. [6A00032]

Male 1cy, October. T1 duller than in ad male. Beware that, unlike in this individual, in some young males the TC are fringed as in females. Young males typically show juv TT and TC until Nov-Dec. [6A00050]

Female 2cy+, October. T1 can be like in young males, but black band is typically duller. Wide white fringe to TC which goes around the tip. [6A00049]

Female 1cy, August. Such a dull T1 is typical of juv females, but beware of individual variation. Young females typically show juv TT and TC until Mar. [6456714]

Male (1cy), November. Rusty colour reaches outer GC in almost all ad males and many young males (72% of 1cy males, Ottenby, n=50). Note also that in males the light-coloured tip of the GC is often larger. LC and MC without fringing, and if fringing is present then it is typically brownish and narrow. Many females show no fringing as well. [6432591]

Female (1cy), October. Outer GC with plain white tip. Some young males show this coloration. Smaller light tip than in males. LC and MC often with fringing, especially in young females. [6A00022]

Male (2cy+), May. Both ad and young males may show full black bill, but only when in breeding plumage. [7066194]

Male (1cy), October. While in eclipse or post-juv plumage, bills of ad and young males are similar: orange on the side and no bill-spots (or sometimes one or two). As in this bird, the orange often appears dirtied with grey compared to the clear orange of young females but many males show clear orange too. [6A00051]

Female (1cy), September. Number of spots can be very variable, from none (as in males) to many and large and clustered (as in ad females), but typically between 1 and 8, small and separate. [6432637]

Female (2cy+), October. Many spots, large and clustered. [6A00044]

More Anas crecca:

Ageing autumn
Moult

Ringers’ DigiGuide main page

Ringers’ DigiGuide is sponsored by:

Hemsidan producerad i samarbete med
BirdLife Sverige