It shall be unlawful for any person or persons to engage in fishing or dredging for shellfish in any of the channels leading to and from the harbor of New York, or to interfere in any way with the safe navigation of those channels by ocean steamships and ships of deep draft.

Any person or persons violating the foregoing provisions of this section shall be deemed guilty of a misdemeanor, and on conviction thereof shall be punished by fine or imprisonment, or both, such fine to be not more than $250 nor less than $50, and the imprisonment to be not more than six months nor less than thirty days, either or both united, as the judge before whom conviction is obtained shall decide.

It shall be the duty of the United States supervisor of the harbor to enforce this section, and the deputy inspectors of the said supervisor shall have authority to arrest and take into custody, with or without process, any person or persons, who may commit any of the acts or offenses prohibited by this section: Provided, That no person shall be arrested without process for any offense not committed in the presence of the supervisor or his inspector or deputy inspectors, or either of them: And provided further, That whenever any such arrest is made the person or persons so arrested shall be brought forthwith before a magistrate judge, judge, or court of the United States for examination of the offenses alleged against him; and such magistrate judge, judge or court shall proceed in respect thereto as authorized by law in case of crimes against the United States.