The dog, who has since been named "River", was later rescued.
RELATED: Pit bull left to drown in cage at water's edge in New Jersey
The Monmouth County prosecutor's office is now looking for 36-year-old Aaron Davis.
A woman walking on the beach in Highlands early Monday spotted the gray and white puppy cowering in a cage as the tide came in.
The woman who rescued "River" plans to adopt him.
RELATED: Woman who rescued pit bull left to drown in cage plans to adopt him
Send a News Tip to Action News
Learn More About 6abc Apps