Common Sandpiper on the rocks

Came upon this Common Sandpiper (Actitis hypoleucos) today on rocks near a busy boat ramp.

Not uncommon behaviour, but first time I've spotted the species anywhere near the ramp.

Bird took off to sandier stretch of shore when I tried to clamber into position for shot from better angle.

Same problem with this Black-fronted Dotterel (Elseyornis melanops). But it's always difficult separating them from their muddy habitats. 
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