Modifiers matching shorebird:

• marine,
• smaller,
• small,
• migrant,
• migratory,
• modern,
• breeding,
• coastal,
• larger,

Simple categories matching migrant:

• sparrow,
• population,
• bird,
• group,
• fish,
• organization,
• waterbird,
• language,
• sandpiper,
• warbler,
• visa,
• songbird,
• labourer,
• worker,
• passerine,
• insectivore,
• finch,
• shorebird,
• thrush,