Modifiers matching labourer:

• unskilled,
• migrant,
• skilled,
• casual,

Simple categories matching migrant:

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