Fishery Regulations

The sustainability of the American lobster harvest is built on a foundation of strict, often self-policed, regulations that protect the breeding stock. These measures are managed jointly by the Atlantic States Marine Fisheries Commission (ASMFC) and individual state agencies.

The Double Gauge (Min & Max Size)

Unlike many fisheries that only set a minimum catch size, the lobster fishery enforces both a minimum and maximum carapace length. Every lobster is measured on the boat with a brass gauge before it is kept or released.

Carapace length is measured from the rear of the eye socket to the posterior edge of the body shell, parallel to the centerline. This measurement excludes the tail and claws, providing a consistent standard regardless of the lobster's posture.

V-Notching

One of the most unique conservation tools in any fishery. When a lobsterman catches a female bearing eggs (“berried female”), they carve a small V-shaped notch into her right uropod (second tail flipper from the right). This mark signals to all fishermen that she is a proven breeder and must be released—even after her eggs have hatched and the V-notch is the only remaining sign.

The notch persists through several molts (typically 2–4 years depending on molting frequency), providing extended protection. In Maine, it is illegal to harvest any female with a visible V-notch or any female carrying eggs. This practice is widely credited as one of the most important reasons the Gulf of Maine lobster population has remained robust.

Owner-Operator Law

Maine's owner-operator law is unique among U.S. fisheries. The holder of a lobster license must be physically present on the vessel when traps are hauled. You cannot hire someone else to fish your traps, and you cannot own multiple boats fishing under your license.

This law prevents corporate consolidation of the fishery and ensures that every license holder has a personal, long-term investment in the health of their local fishing grounds. Combined with a zone-based management system (Maine is divided into seven lobster management zones, A through G, each with a local council), this keeps decision-making close to the communities that depend on the resource.

Trap Limits

Each commercial license holder in Maine is limited to 800 traps. This cap prevents overcapitalization and “gear wars” where fishermen compete by setting ever more traps. All traps must be tagged with the license holder's identification, and each trap must include:

• Escape vents: Rectangular or circular openings that allow undersized lobsters and non-target species to exit the trap.
• Biodegradable panels: A section of the trap held together with degradable fasteners (hog rings, untreated cotton, etc.) that will rot and create an opening if the trap is lost, preventing “ghost fishing.”

Whale-Safe Gear Requirements

To reduce the risk of entanglement with the endangered North Atlantic right whale, NOAA Fisheries requires:

• Weak links: Breakaway connectors at the buoy that release under moderate force, allowing an entangled whale to break free.
• Sinking groundline: The rope connecting traps along the bottom must sink rather than float, reducing the vertical line footprint in the water column.
• Seasonal closures: Thousands of square miles of fishing grounds are closed seasonally when right whales are known to be present.
• Gear marking: Color-coded markings on buoy lines identify the fishery and jurisdiction, enabling traceback of any entanglement event.