Writing for Guernica, Kimon de Greef describes Birdsport:
Prices start at around one hundred dollars but rise quickly for promising singers. On his last trip, [the smuggler] spent four thousand dollars on a bird for himself.
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“This one’s angry,” [the smuggler] said appreciatively. “I look for birds like that.”
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When two men agree to race, they lift their cages from these improvised pegs and place them, inches apart, on a shoulder-height spike driven into the ground for just this purpose. As soon as the birds see each other, they begin singing to defend their turf; the two judges tally each burst of whistles, and the first bird to fifty wins.