Red Knot: a two-minute wildlife lesson

Shorebirds · day 3 of 7

Five facts

1. Some red knots fly more than 14,000 km each year, from the Arctic to the tip of South America, then all the way back.
2. Its bill can feel tiny changes in water pressure, so it finds clams hidden under wet sand without seeing them.
3. Its muscular stomach thickens for hard shellfish in winter and shrinks for soft Arctic food. The switch can take just six days.
4. On their spring stopovers, knots eat almost nonstop and can double their body weight in about 10 to 14 days.
5. One knot, tagged B95 and nicknamed Moonbird, was still flying when last seen in 2014, at 20 years old or more.

The quiz

1. How far do some red knots fly each year, one way?

• About 500 km
• About 2,000 km
• More than 14,000 km (correct)
• About 5,000 km

Some travel more than 14,000 km from the Arctic to South America.

2. How does a red knot find clams buried in wet sand?

• It senses changes in water pressure with its bill (correct)
• It listens for them tapping
• It smells them from the air
• It waits for them to surface

Sensors in its bill pick up changes in water pressure.

3. How fast can a red knot's gizzard change size?

• In 2 years
• In as little as six days (correct)
• It never changes
• In about 6 months

The changes can happen in as little as six days.

4. What can a red knot do during a spring stopover of 10 to 14 days?

• Grow new flight feathers
• Raise a family
• Lose half its weight
• Double its body weight (correct)

Eating almost nonstop, it can double its weight in about 10 to 14 days.

5. What was the nickname of the red knot tagged B95?

• Starbird
• Moonbird (correct)
• Sunwing
• Captain Knot

B95 was nicknamed Moonbird and was at least 20 years old.

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