Fauna
Bird

Western Sandpiper

Calidris mauri

Western sandpipers gather in massive, coordinated flocks along Pacific mudflats during their energetic annual migrations between Alaskan tundra and tropical wintering sites. They use their slightly decurved bills to probe wet sediment for tiny crustaceans, marine worms, and nutrient-rich surface biofilm. Females possess slightly longer bills than males, allowing pairs to forage at different sediment depths and reduce direct competition.

MigratoryShorebirdCoastal
Western Sandpiper reference1 / 7
Alan D. Wilson / CC BY-SA 3.0 · cc-by-sa
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Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Key facts
Diet & preyMarine Worms, Small Crustaceans, Surface Biofilm
Predators
  • Peregrine Falcon
  • Merlin
  • Northern Harrier
ThreatsCoastal development, habitat loss at stopover sites, climate change
HabitatsMudflats, estuaries, sandy beaches, tundra breeding grounds
Life span4–9 years
Classification
  1. OrderCharadriiformes
  2. FamilyScolopacidae
  3. GenusCalidris
  4. SpeciesCalidris mauri
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Safe to observe at a normal distance.
What to notice
Look for a small, dark-legged shorebird with a slightly drooping, tapered bill.
Support conservation
Maintain a respectful distance of at least 50 meters and avoid flushing resting flocks.
Responsible observation
  • Observation: Use a spotting scope to scan feeding flocks on coastal mudflats during falling tides.
  • Patience: Watch for their rhythmic probing motion along the water line.
  • Etiquette: Keep dogs leashed and avoid approaching resting shorebirds on beaches.
Related species
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