Telling the difference between a sharp-shinned hawk and a merlin can be tricky for birders. While both are small, forest-dwelling falcons, there are some key identification features to look for. In this article, we’ll go over the field marks, size, shape, plumage, flight patterns, habitat, and behaviors that set these two raptors apart.
Size and Shape
The most noticeable difference between sharp-shinned hawks and merlins is their size. Sharp-shinned hawks are petite falcons, whereas merlins are tiny. A sharp-shinned hawk ranges from 9-13 inches in length with a 20-30 inch wingspan. Merlins measure 7-12 inches in length with a wingspan of just 20-24 inches.
When seen together, the size difference is obvious. Sharp-shinned hawks have broader wings and a wider girth than the more compact merlin. A merlin’s wings and tail also appear more pointy.
Sharp-shinned hawks have proportionally longer, skinnier legs than merlins. Their tails are also longer in comparison to their wingspan. When perched, a sharp-shinned will appear leggier and less stocky than a merlin.
Key Size Differences
Species | Length | Wingspan |
---|---|---|
Sharp-Shinned Hawk | 9-13 inches | 20-30 inches |
Merlin | 7-12 inches | 20-24 inches |
Plumage
When it comes to plumage, sharp-shinned hawks display more variety than merlins. Sharp-shinned hawks occur in light and dark color morphs. The light morph adults have blue-gray backs and wings, reddish barred underparts, and bright yellow eyes. The dark morph is chocolate brown above and streaked below.
Female sharp-shinned hawks are noticeably larger and browner than males. Juveniles have brown backs, a heavily streaked belly, and orange eyes.
Meanwhile, merlin plumage remains relatively consistent. Adults are slate-gray above with a finely streaked underbelly. The tail shows neat black-and-white banding. The face is boldly marked with a black “mustache” stripe. Females and males look alike, while juveniles are buffier overall with brown streaks below.
Plumage Comparison
Species | Adult Plumage | Juvenile Plumage |
---|---|---|
Sharp-Shinned Hawk | Light morph: blue-gray back, reddish underparts, yellow eyes Dark morph: chocolate back, streaked underparts |
Brown back, streaked underparts, orange eyes |
Merlin | Slate-gray back, streaked underbelly, black & white banded tail | Buffy brown, heavy streaks below |
Flight Style
Sharp-shinned hawks and merlins also differ in their flight style and wingbeats. Sharp-shinned hawks have fast, powerful bursts of flapping. Their flight profile appears energetic and bouncy as they flap several times and then glide.
Merlins have a slower, more methodical flight. Their wingbeats are nearly continuous with occasional brief glides. In direct comparison, merlins’ flight seems smoother and less punctuated than sharp-shinned hawks.
When hunting, merlins often fly low and fast over open ground as they pursue prey. Sharp-shinned hawks move through forests on shorter, more maneuverable wings. They can also hover-hunt by beating their wings quickly when spotting prey.
Flight Style Comparison
Species | Flight Style |
---|---|
Sharp-Shinned Hawk | Fast and energetic bursts of flapping followed by brief glides |
Merlin | Nearly continuous wing beats with occasional short glides |
Habitat
Sharp-shinned hawks and merlins generally occupy different habitats in North America. Sharp-shinned hawks thrive in dense, mature forests across Canada and the northern United States. They nest in conifers and hunt amongst the trees.
Merlins inhabit more open environments like prairies, parks, wetlands, and coastal areas. They nest on rocky outcrops and hunt over grasslands and fields. Their range extends farther south than sharp-shinned hawks.
There is some habitat overlap on forest edges and where prairies meet woodlands. But finding a merlin deep in an evergreen forest would be unusual, as it would be rare to spot a sharp-shinned hawk perched on a power line over an open marsh.
Typical Habitats
Species | Habitat |
---|---|
Sharp-Shinned Hawk | Mature forests, especially conifers |
Merlin | Open country, prairies, parks, coastal regions |
Hunting Behavior
Sharp-shinned hawks and merlins have differing hunting strategies tailored to their habitats. As ambush predators, sharp-shinned hawks often remain perched, still-hunting for prey that crosses their path. They plunge from a perch onto unsuspecting birds with their powerful talons.
Merlins more actively chase down prey in flight over open areas. They pursue birds like swallows or flickers back to their nest sites. Sometimes they overwhelm prey with their speed and agility mid-air. Merlins occasionally hunt from perches too, but overall favor a more active, aerial hunting style than sharp-shinned hawks.
Hunting Strategies
Species | Hunting Behavior |
---|---|
Sharp-Shinned Hawk | Perch and ambush hunting |
Merlin | Aerial pursuit of prey |
Vocalizations
Sharp-shinned hawks and merlins sound quite different when calling. A sharp-shinned hawk’s most common call is a rapid “kekekekeke.” They also make a high whistled “peer.”
Merlins are very vocal and have a broad repertoire of trills, chatters, whistles, and calls. A common merlin call is a rapid, rolling “killy-killy-killy.” They also give a whistled “pwee” note.
Learning the vocalizations of sharp-shinned hawks and merlins takes practice. But their calls can provide a helpful clue, as their repertoires sound distinct.
Common Vocalizations
Species | Typical Call |
---|---|
Sharp-Shinned Hawk | Fast “kekekekeke” |
Merlin | Rolling “killy-killy-killy” |
Geographic Range
Sharp-shinned hawks and merlins have overlapping ranges across much of Canada and the northern United States. But merlins range farther south than sharp-shinned hawks, even wintering in South America and the Caribbean islands.
Sharp-shinned hawks are less migratory than merlins. Northern sharp-shins head south for winter, while more southern populations are resident year-round. Merlins are strongly migratory, traveling from boreal and temperate nest sites to overwinter in the southern U.S, Mexico, and beyond.
When identifying a small falcon, consider the geographic location. In Florida or Texas, it’s far more likely to be a merlin than a sharp-shin. The opposite goes for a sighting in June in Alberta.
Breeding and Wintering Ranges
Species | Breeding Range | Winter Range |
---|---|---|
Sharp-Shinned Hawk | Across Canada, northern and western U.S. | South to southern U.S. and Mexico |
Merlin | Canada, northern U.S., Rocky Mountains | Throughout U.S., south to South America |
Conclusion
Telling apart sharp-shinned hawks and merlins comes down to a combination of factors. Size and proportions are a good starting point, as sharp-shins are distinctly larger. Shape, plumage, flight style, habitat, hunting behavior, vocalizations, and geographic location can all aid identification.
With practice, birders can learn to recognize the characteristics of these small falcons. The key is observing enough birds to get a feel for the differences. Patiently taking note of size, shape, behavior and other field marks will sharpen your skills at identifying sharp-shinned hawks, merlins, and other tough-to-tell-apart bird species.