The pair were picked up by officers on Wednesday, November 2 after a member of the public reported people acting suspiciously near Hitchin - 35 miles from Uxbridge.
A vehicle parked near the scene was found containing dead pheasants and was seized.
Inspector Duncan Sales, from Hertfordshire Constabulary, said: “We will not tolerate poaching in North Herts and will deal robustly with anyone committing this crime.
“To help us fight against poaching we rely on reports from members of the public.
“Therefore I would encourage anyone who witnesses people poaching or behaving suspiciously in the county's rural areas to call us via the police non-emergency number 101."
The 24-year-old man from Hillingdon and the 23-year-old man from Harefield have been released on bail to return to Hatfield Police Station on December 15.
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