When you invade a breeding male Red-winged Blackbird’s territory, he lets you know it, … and know it, and know it. From every perch, he squawked at me continuously and vigorously. It was enough to make me leave — which was his intention.
Even a female got into the act, although she was a little quieter about her displeasure at my presence.
Male Red-winged Blackbirds arrive on spring migration as soon as the snow melts. First arrivals claim the biggest and best territories and proceed to collect as many females as their territory can support. Some males have as many as 15 females on their territory. While this sounds like a good recipe for spreading the male’s genes, genetic studies have shown that less than half of the nestlings reared in a male’s territory may actually be his progeny! But one-half of 12 nests times 4 young per nest is still a lot of offspring.