Ecology Merlin (bird)

f. c. columbarius hunting northern blue jay (cyanocitta cristata bromia), mount auburn cemetery, massachusetts, united states

merlins rely on speed , agility hunt prey. hunt flying fast , low, typically less 1 m (3.3 ft) above ground, using trees , large shrubs take prey surprise. capture prey in air, , tail-chase startled birds. throughout native range, merlin 1 of able aerial predators of small mid-sized birds, more versatile if larger hobbies (which prefer attack in mid-air) , more nimble sparrowhawks (which go birds resting or sleeping in dense growth). breeding pairs hunt cooperatively, 1 bird flushing prey toward mate.

the merlin readily take prey flushed other causes, , can example seen tagging along sharp-shinned hawks (accipiter striatus) catch birds escape ambush predator open air. quite unafraid, , readily attack moves conspicuously. merlins have been observed trying catch automobiles , trains, , feed on captive birds such snared in mist nets used ornithologists. under adverse conditions, 1 in 20 targets caught, , under conditions every other attack successful. sometimes, merlins cache food eat later.

in particular during breeding season, of prey smallish birds weighing 10–40 g (0.35–1.41 oz). such species taken, local preferences whatever abundant—be larks (alaudidae), pipits (anthus) or house sparrows (passer domesticus)—and inexperienced yearlings favorite. smaller birds avoid hunting merlin if possible. in cayman islands (where occurs in winter), bananaquits noted die of apparent heart attack or stroke, without being physically harmed, when merlin went @ them , not escape.

larger birds (e.g. sandpipers, flickers , rock pigeons heavy merlin itself) , other animals—insects (especially dragonflies , moths), small mammals (especially bats , voles) , reptiles—complement diet. these more important outside breeding season, when can make considerable part of merlin s diet. example in norway, while small birds breeding merlin s staple food, exceptional breeding success seems require abundance of microtus voles.

corvids primary threat eggs , nestlings. adult merlins may preyed on larger raptors, peregrine falcons (f. peregrinus), eagle-owls (e.g., great horned owl, bubo virginianus), , larger accipiter hawks (e.g., northern goshawk, a. gentilis). in general however, carnivorous birds avoid merlins due aggressiveness , agility. desire drive larger raptors away territory pronounced identifying characteristic. quoting 1 popular raptor watching reference, observer may use aggressive tendency identification purposes , means of detection. high-flying merlins betray , distinguish because vigorously harassing raptor (even ones large golden eagle).

reproduction

falco columbarius egg



nestlings

breeding occurs typically in may/june. though pairs monogamous @ least breeding season, extra-pair copulations have been recorded. nest sites have dense vegetative or rocky cover; merlin not build proper nest of own. use abandoned corvid (particularly corvus crow , pica magpie) or hawk nests in conifer or mixed tree stands. in moorland—particularly in uk—the female make shallow scrape in dense heather use nest. others nest in crevices on cliff-faces , on ground, , may use buildings.

three 6 (usually 4 or 5) eggs laid. rusty brown eggs average @ 40 mm × 31.5 mm (1.57 in × 1.24 in). incubation period 28 32 days. incubation performed female 90%; male instead hunts feed family. hatchlings weigh 13 g (0.46 oz). young fledge after 30 days or so, , dependent on parents 4 more weeks. first-year merlins (especially males) serve nest helper adult pair. more half—often or all—eggs of clutch survive hatching, , @ least two-thirds of hatched young fledge. however, noted above, in years little supplementary food 1 young in 3 may survive fledging. merlin becomes sexually mature @ 1 year of age , attempts breed right away. oldest wild bird known of 2009 recorded in 13th winter.