The dowitchers and red knots are two groups of migratory shorebirds that are often found together along ocean coasts and inland wetlands across North America. Though they look quite similar to the untrained eye, dowitchers and red knots have some key differences when it comes to their appearance, habitat, migration routes, and feeding behaviors. In this article, we’ll take a close look at how to distinguish these two types of shorebirds from one another.
Quick Identification Tips
Here are some quick tips for identifying dowitchers vs. red knots:
- Size – Dowitchers tend to be larger than red knots
- Bill shape – Dowitchers have a long, straight bill while red knots have a short, thicker bill with a slight downward curve
- Color – Red knots in breeding plumage are reddish underneath while dowitchers tend to be more gray
- Behavior – Dowitchers probe into mudflats searching for food; red knots tend to peck at food sources on the surface
Knowing these basic differences will help you distinguish between dowitchers and red knots when you see them in the field. Now, let’s look at each species in more detail.
Distribution and Habitat
Dowitchers and red knots occupy some of the same habitats and regions during migration and wintering, but their breeding areas are distinct.
Dowitchers
There are three species of dowitchers—the short-billed, long-billed, and Asian dowitchers. The long-billed and short-billed dowitchers have the most overlap with red knots.
- Breeding habitat: Across northern North America from Alaska to central Canada
- Migration and wintering range: Coastlines, inland wetlands, and mudflats across the U.S., Mexico, Central and South America
- Common habitats: Salt marshes, tidal flats, ponds, wet meadows
Red Knots
- Breeding habitat: High Arctic areas of northern Canada and Alaska
- Migration and wintering range: Coasts across the Americas, Galapagos Islands, Atlantic coast of Europe and Africa
- Common habitats: Coastal habitats including beaches, tidal flats, salt marshes
As you can see, while their wintering grounds may overlap, dowitchers breed at more southerly latitudes than red knots. Their habitat preferences also differ slightly, with red knots more specialized for coastal areas.
Appearance
Let’s move on to the finer details of identifying these birds by sight.
Size and Shape
- Dowitchers tend to be larger than red knots with long legs and a robust, chunky body.
- Red knots are smaller and more compact, with a proportionally small head.
Plumage
- Dowitchers tend to be muted gray both above and below.
- Red knots sport more reddish underparts during breeding season.
- Dowitchers have spotted breeding plumage on the back and wings.
- Red knots have a scalloped, gray-and-black back.
Bill Shape
One of the best identification clues is bill shape:
- Dowitchers have a straight, needle-like bill that is 2-3 times the length of its head.
- Red knots have a shorter, stouter bill only slightly longer than the head. Their bill also has a slight downward curve.
Bird | Length | Bill Shape |
---|---|---|
Dowitcher | 11.8-15.8 in (30-40 cm) | Long, thin, straight |
Red knot | 7.9-9.8 in (20-25 cm) | Short, thick, curved slightly down |
Legs and Feet
- Dowitchers have yellowish legs and feet.
- Red knots have dark gray to blackish legs and feet.
Behavior
These birds forage quite differently, which can help identification:
- Dowitchers use their long bill to probe into the mud in search of invertebrates.
- Red knots tend to peck at food sources found near the surface.
Dowitchers have a sewing machine-like feeding action as they probe while walking. Red knots will pick up food items more quickly.
In flight, dowitchers have a slower, more methodical flight style with slower wingbeats. Red knots fly more swiftly and erratically.
Migration
Both dowitchers and red knots make incredibly long migrations each year. However, there are some differences:
Dowitchers
- Travel south beginning in July and August from their breeding grounds.
- Migrate north again in April and May.
- Migration routes span coastlines and Central America.
- Stopover sites with rich food sources are key.
- Some dowitchers even fly nonstop over the Gulf of Mexico.
Red Knots
- Leave Arctic nesting areas in July.
- Use key staging sites like Delaware Bay to feed and fatten up.
- Fly down Atlantic coast to southern tip of South America.
- Return north by following migratory shorebird “superhighways”.
- Complete one of the longest migration routes of any bird.
The red knot’s migratory path loops from pole to pole in one of the animal kingdom’s most amazing navigation feats. Dowitchers also navigate immense distances but have more flexibility in their routes.
Interesting Facts
A few more fascinating bits about each bird:
Dowitchers
- Use a tactic called “sewing” to probe for food, quickly opening and closing their bill.
- Have special feathers around their bill called “rictal bristles” that help them find food.
- Long-billed dowitchers make a “keek” call while feeding.
- Nest on the ground in marshy areas across northern North America.
Red Knots
- Make annual migrations as far as 9,300 miles (15,000 km) roundtrip.
- Can double their weight before migratory flights by eating mollusks, crustaceans, and horseshoe crab eggs.
- Use knots and bends in the intestines to shrink their digestive organs while fattening up.
- Breed only in the remote Arctic regions during the short summer season.
Conclusion
While dowitchers and red knots occupy similar habitats and migration flyways through North America, they have distinct differences when it comes to their size, plumage, bill shape, foraging methods, and breeding ranges. The long, straight bill of dowitchers compared to the shorter, curved bill of the red knot provides one of the best field marks for identification. Getting a closer look at the intricate plumage patterns, body proportions, and feeding behaviors of these birds takes much patience and practice. But being able to distinguish these two amazing migratory shorebird groups provides a great sense of satisfaction for any birder.