The is a United States Coast Guard Cutter

United States Coast Guard Cutter

Cutter is the term used by the United States Coast Guard for its commissioned vessels. A Cutter is or greater in length, has a permanently assigned crew, and has accommodations for the crew to live aboard...

 and an icebreaking tug

USCG Icebreaking Tug

The USCG Bay-class icebreaking tug is a class of icebreaking tugs of the United States Coast Guard, with hull numbers WTGB 101 through to WTGB 109.They can proceed through fresh water ice up to thick, and break ice up to thick, through ramming...

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Design

The Biscayne Bay is the fourth ship in a class of ice-breaking tugboat designed to have greater multi-mission
capabilities than the 110' Calumet Class Harbor Tug (WYTM). The most significant differences include: greater horsepower, greater speed, longer range,
increased ice-breaking capability, a hull lubrication system (bubbler), greater degree of automation, and better habitability.