Description Merlin (bird)

juvenile, f. c. columbarius

the merlin 24–33 cm (9.4–13.0 in) long 50–73 cm (20–29 in) wingspan. compared other small falcons, more robust , heavily built. males average @ 165 g (5.8 oz) , females typically 230 g (8.1 oz). there considerable variation, however, throughout birds range and—in particular in migratory populations—over course of year. thus, adult males may weigh 125–210 g (4.4–7.4 oz), , females 190–300 g (6.7–10.6 oz). each wing measures 18.2–23.8 cm (7.2–9.4 in), tail measures 12.7–18.5 cm (5.0–7.3 in) , tarsus measures 3.7 cm (1.5 in). such sexual dimorphism common among raptors; allows males , females hunt different prey animals , decreases territory size needed feed mated pair.

the male merlin has blue-grey back, ranging black silver-grey in different subspecies. underparts buff- orange-tinted , more or less heavily streaked black reddish brown. female , immature brownish-grey dark brown above, , whitish buff spotted brown below. besides weak whitish supercilium , faint dark malar stripe—which barely recognizable in both palest , darkest birds—the face of merlin less patterned in other falcons. nestlings covered in pale buff down feathers, shading whitish on belly.

upperside pattern of male (presumably f. c./a. pallidus) wintering in little rann of kutch, gujarat, india

the remiges blackish, , tail has 3–4 wide blackish bands, too. light males have faint , narrow medium-grey bands, while in darkest birds bands wide, tail appears have narrow lighter bands instead. in of them, however, tail tip black narrow white band @ end, pattern possibly plesiomorphic falcons. altogether, tail pattern quite distinct though, resembling of aplomado falcon (f. berigora) , (in light merlins) typical kestrels. eye , beak dark, latter yellow cere. feet yellow, black claws.

light american males may resemble american kestrel (f. sparverius, not typical kestrel), merlin males have grey , tail rather reddish-brown of kestrels. light european males can distinguished kestrels brown wings. in north of south asia, wintering males may confused red-necked falcon (f. chicquera) if fly away observer , head (red on top in f. chicquera) , underside (finely barred black in f. chicquera) not visible.