It is a Science fiction novel.
Set in Earth's future where giant genetically engineered birds are used as flying vehicles. If I remember correctly, it is due to end of fossil fuels.
The main character is a cop or detective. Police fly on birds of prey. Civilians have ride more mundane species of giant birds, such as song birds.
I read this in paperback between 1992 and 1998.
The Cover had giant falcon or other bird of prey with a police light bar on it.
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