On Journey North’s website they have a great way to distinguish a winter/migrant robin from a spring robin:Winter and migratory behaviors include:
• Feeding in flocks
• Eating fruit
• Flying in flocks
• Getting along peacefully
Spring behaviors include:
• Running on lawns
• Eating worms
• Singing
• Territorial battles
• Carrying nesting materials
To learn more about Journey North’s Spring Robin program, see this site.