Jurors in December convicted Aaron D. Davis of Long Branch of fourth-degree animal cruelty following a three-day trial before County Superior Court Judge Marc C. LeMieux in Freehold.
The jurors acquitted him of attempting to kill the dog, who was rescued.
As part of Friday's sentence, the judge ordered Davis to pay $731 restitution and to complete 156 hours of community service, the Monmouth County Prosecutor's Office said in a release.
Davis also will be banned from owning pets while on parole, the release said.
A Highlands resident testified during the trial that she was out on a daily run with her dog early on July 30, 2018 when she spotted the caged pit in the rising tide where Sandy Hook Bay and the Shrewsbury River converge.
She rescued the puppy, who was later named "River," and the Monmouth County Prosecutor’s Society for the Prevention of Cruelty to Animals Division and Highlands police investigated.
Davis left the animal there following a dispute with his girlfriend's ex-boyfriend at the time, prosecutors said during the trial.
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