Skirmish!

Despite a long winter that slowed spring arrivals, robins are making progress toward breeding grounds. One-third of this week's FIRST reports are from six provinces in Canada, and three NOPs reported first robins. Wisconsin reported the most FIRSTS and WAVES, while Pennsylvania reported the most SONG. It's been a long wait for northerners:

• "Blizzard on Friday, Robin singing on Monday."
  Hinckley, MN (April 7)
• "At last! One robin giving call notes but no full song." Juneau, AK (April 6)
• "FINALLY! We have been waiting so long for our beloved robins to return." Winnipeg, MB (April 4)

Arrivals are Rivals
The first ones to return and set up territory boundaries are often the robins who were in the same spot the summer before. Other robins that migrate through get chased off by the male and female who have the territory. During fine weather, male robins spend their time singing, feeding, and investigating their territories. As hormones increase, robins get uncomfortable being close together, and they often skirmish with other males.

Defending Territories
Robins may also fight when they arrive somewhere and want to claim a territory. When male robins return to their territories, they usually sing from various perches. Maybe they're thinking, "I think this is my territory, but if you fly over here and chase me off, then I'll know it's YOUR territory." Skirmishes usually settle the boundaries quickly, but the birds will fight harder to win a territory that has a special resource, such as a birdbath.

What to Watch For:
Where females have begun to arrive, nesting is next. Put nesting behaviors on our map by knowing what to report.

• Robin Checklist for Spring Observations

What does a robin look for when choosing a territory in spring? See why claiming and defending a good territory is so important to a male robin:

• Will a Robin Choose Your Neighborhood?