In the species called Great-tailed Grackle (perfect name), neither the male or the female is usually faithful = it is a polygynous species. Males defend a small territory but only after they reach three years of age. But, it doesn’t matter because females may switch the area where they nested either during the current breeding season or between seasons. Great-tailed Grackles are sexually dimorphic and the brown females are half the size of the big, purple-hued glossy male with the long keeled tail (photo). Whereas many bird species are affected by agriculture or expanding civilization, Great-tailed has expanded it range tremendously in the past 50 years. Thirty years ago Great-tailed Grackles would never be found on the Chico, but today they breed in many Colorado counties and throughout the Midwest and West.
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