Is a fishing license required on a private pond?

Question

Suppose there is a pond that is privately stocked by the pond association, a group of homeowners. The pond has no public access; town residents may access the pond through a town beach, or waterfront property owners may access the pond via their own shoreline. Marine patrol does patrol the pond, but have never heard of an officer actually asking a fisherman for his license. Fish and Game does not patrol.

Can anyone with legal access to the pond fish without a license?

I am located in New Hampshire, but I'd be interested in knowing whether there is a standard among states.

Answer 1

In Washington, no license is required if the pond or lake has been evaluated by the state and you have a fish-stocking permit, which essentially means the fish have to come from an approved source and the water has to be cut off from the outside world (and can't overflow to the outside). In New Hampshire, the requirement to have a license has an exception

The provisions of RSA 214:1 shall not apply to resident land owners while upon their own land or to the owner's children under 16 years of age when accompanied by the owner or another licensed person 18 years of age or over on such land, to persons fishing in ponds operated and maintained in an aquaculture operation...

Answer 2

They will differ from state to state, depending on each state's own wildlife, fish and game administration and its rules and regulations.

Factors will be public/private access, state/federal licenses required to raise and stock fish, the water source and water rights, etc.

Each state's agency will have published documents on fishing rules; see https://www.fws.gov/offices/statelinks.html to find each state's agency.

I.e. Montana: http://fwp.mt.gov/fishing/regulations/ponds.html

No fishing license is required to fish on licensed, privately stocked fish ponds. Fishing license requirements apply to all other ponds and/or waters on private land.

And

A person who owns or lawfully controls a private fish pond may obtain a license from FWP to stock the pond with fish. Only lawfully purchased fish may be planted.