At a Glance
| US MPA count | ~1,700 MPAs in US waters (NOAA) |
| Restrictions vary | No-take fishing, no-anchor zones, permit requirements, speed limits — depends on the specific MPA and zone |
| Florida Keys NMS | No anchoring on coral; mooring fields provided in SPAs |
| Find MPA boundaries | marinecadastre.gov — all US MPAs mapped with zone details |
| Whale rule | 100-yard minimum distance from humpback whales in Hawaiian Islands NMS |
Marine Protected Areas exist on a spectrum from minimally restrictive to completely off-limits, and sailors who treat "MPA" as a single category will find themselves either over-complying (anchoring miles offshore when it's perfectly legal closer in) or under-complying (anchoring on coral because they assumed the mooring field was just a convenience). Understanding the specific zone type and its associated rules is the only way to navigate this correctly.
NOAA administers roughly 1,700 MPAs in US waters — a category that spans everything from National Marine Sanctuaries and National Monuments to state marine reserves and locally managed estuary programs. The rules differ dramatically. A state marine reserve may prohibit only commercial fishing. A Sanctuary Preservation Area in the Florida Keys may prohibit anchoring, certain types of boating, and require specific behaviors around wildlife. Reading the actual zone regulations for your cruising area is not bureaucratic overkill — it's essential seamanship.
What "MPA" Actually Means for Sailors
The broadest category of MPA is a no-take zone — an area where commercial and sometimes recreational fishing is prohibited, but where sailing, anchoring, and other boating activities continue normally. Most sailors pass through these zones without knowing it, because the restrictions are on extractive use, not navigation.
The restrictions that directly affect sailors concentrate in a smaller number of designated areas: National Marine Sanctuaries (NMS), certain National Monuments, and state marine parks. Even within these, the no-anchor and permit requirements typically apply to specific sub-zones, not the entire protected area. The Florida Keys National Marine Sanctuary covers 2,900 square nautical miles; anchoring restrictions apply within the Sanctuary Preservation Areas and Existing Management Areas, which are a subset of that total.
Some MPAs have vessel speed restrictions — particularly in areas with endangered marine mammals or protected nesting habitat. Some require permits for specific activities (diving commercial operations, research, filming). A very small number prohibit vessel transit entirely through certain zones. Knowing which category you're dealing with before you arrive is worth the twenty minutes of research.
Florida Keys National Marine Sanctuary
The Florida Keys NMS is the MPA that East Coast and Caribbean-circuit sailors are most likely to encounter, and it's one of the most carefully managed. The Sanctuary contains the only living barrier reef in the continental US, and reef health has been in measurable decline for decades — water temperature, water quality, storm damage, and historical anchor damage have all contributed.
The practical rules for sailors in the Keys: do not anchor on coral anywhere in the sanctuary. This is not just a zone-specific rule — it's a sanctuary-wide prohibition. In the 27 Sanctuary Preservation Areas (the most strictly managed zones), anchoring is prohibited entirely and mooring buoys are provided. In areas outside SPAs, anchoring in sand is permitted. The mooring buoy network is extensive — hundreds of buoys throughout the Keys — and the $20–35 nightly fee is modest given what it funds.
Motor-only zones exist in some sensitive shallow-water areas. Wildlife viewing distances apply near protected nesting birds. The NOAA Keys sanctuary website maintains the current regulations and zone maps, and the Florida Keys cruising guides include sanctuary rule summaries.
Channel Islands National Marine Sanctuary (California)
The Channel Islands NMS off the Southern California coast protects a chain of islands and the surrounding water column — one of the most biologically productive marine environments on the Pacific Coast. Kelp forests, sea lion rookeries, seabird nesting colonies, and cold-water upwelling make the islands a significant wildlife destination for both marine biologists and sailors.
For sailors, anchoring at the Channel Islands is generally permitted in sand and away from kelp beds. The no-anchor rule applies to kelp and rocky areas — which is most of the inshore terrain around the islands. Sand anchorages exist at several locations on the leeward (typically north and east) sides of the islands; local charts and cruising guides identify them specifically.
Some island areas have seasonal restrictions to protect nesting seabirds — going ashore is restricted or prohibited in these zones during nesting season. California's state marine reserves within the sanctuary add additional no-take restrictions that affect fishing, not navigation. The sanctuary's website provides current zone maps and restriction calendars.
Gray's Reef National Marine Sanctuary (Georgia)
Gray's Reef NMS in the South Atlantic off the Georgia coast is small — roughly 22 square miles — and less familiar to most cruisers than the Keys or the Channel Islands. It's a live-bottom reef ecosystem, one of the largest shallow-water reefs in the Southeast. Loggerhead sea turtles, right whales in winter, and a diverse reef fish community make it ecologically significant.
Anchoring is prohibited throughout the sanctuary. The seafloor structure — live bottom with sponges, corals, and other sessile organisms — would be damaged by anchor and chain contact. Vessels visiting Gray's Reef (primarily dive boats) must use mooring buoys or drift dive. For cruising sailors, Gray's Reef is primarily a transit zone to be aware of rather than a destination anchorage.
Hawaiian Islands Humpback Whale National Marine Sanctuary
The Hawaiian Islands Humpback Whale NMS covers the shallow waters around Maui, Lana'i, Moloka'i, and parts of the Big Island — the primary Hawaiian breeding and calving grounds for North Pacific humpback whales. Whale season runs roughly November through April, with peak activity January through March.
The regulation that directly affects sailors: vessels must maintain a minimum distance of 100 yards from humpback whales at all times. This is not a sanctuary-specific rule — it's federal law under the Marine Mammal Protection Act — but the sanctuary waters are where compliance is most relevant and most enforced. If a whale surfaces closer than 100 yards, you must reduce speed and alter course to increase the distance; you may not position yourself to intercept or approach a whale closer than that distance.
In practice, during peak season in the channels between Maui and Lana'i, humpbacks are present in large numbers. Sailing through the area means being consistently alert for surfacing whales, maintaining situational awareness about your course relative to whale locations, and being prepared to alter sail or motor immediately. A 40-foot humpback surfacing close aboard is not a subtle event — but it can happen faster than you'd expect, particularly when the animals are resting at the surface.
The Great Barrier Reef Marine Park (International)
For sailors making Australian passages, the Great Barrier Reef Marine Park is the most complex MPA in the world in terms of scale and zone management. The park covers roughly 344,000 square kilometers and has a detailed zone map with eight different zone types, each with different permitted activities.
The zone types range from General Use zones (most boating and recreational fishing permitted) to Preservation zones (no entry except with specific research permits). The zones most relevant to sailors are the Marine National Park zones — the green zones on the official zoning map — where no fishing, collecting, or anchoring except in specific designated areas is permitted.
Navigating the Great Barrier Reef requires the official GBRMPA zoning maps, available as digital chart overlays compatible with most chartplotters. Tourist zone permits (required for commercial operations visiting specific areas) are not required for private recreational vessels, but understanding which zone you're anchoring in is essential. The reef is not monolithic — large stretches are accessible to standard boating and anchoring without restriction; the green zones are specific and the maps are clear.
Finding MPA Regulations Before You Arrive
For US waters, MarineCadastre.gov is the authoritative starting point. The National Viewer tool maps all US MPAs with zone boundaries, zone type descriptions, and links to the governing regulations for each protected area. The NOAA Office of National Marine Sanctuaries website (sanctuaries.noaa.gov) provides detailed regulations, zone maps, and vessel guidance for each of the 15 National Marine Sanctuaries.
For international destinations, research specific to each country is required. Most established cruising destinations with MPAs have dedicated agency websites: the Great Barrier Reef Marine Park Authority (gbrmpa.gov.au), Belize's Coastal Zone Management Authority, the Eastern Caribbean's various island tourism and fisheries ministries. Cruising guides for specific regions typically summarize the current MPA rules for the major protected areas along the route.
Further Reading in This Series
Frequently Asked Questions
How many Marine Protected Areas exist in US waters and what do they mean for sailors? NOAA administers roughly 1,700 MPAs in US waters, spanning everything from National Marine Sanctuaries and National Monuments to state marine reserves and locally managed estuary programs. The restrictions that directly affect sailors — no-anchor zones, permit requirements, vessel speed limits — concentrate in a smaller number of National Marine Sanctuaries and certain National Monuments. Most sailors pass through many MPAs without knowing it, because the restrictions in the broadest category are on extractive use, not navigation.
What are the anchoring rules in the Florida Keys National Marine Sanctuary? Anchoring on coral is prohibited throughout the entire Florida Keys NMS — not just in specific sub-zones. In the 27 Sanctuary Preservation Areas, anchoring is prohibited entirely and mooring buoys are provided, with nightly fees of $20–35. In areas outside SPAs, anchoring in sand is permitted. The mooring buoy network is extensive, with hundreds of buoys throughout the Keys.
What restrictions apply to sailors in the Hawaiian Islands Humpback Whale National Marine Sanctuary? Vessels must maintain a minimum distance of 100 yards from humpback whales at all times — a requirement under the Marine Mammal Protection Act that is most relevant and most enforced in sanctuary waters. If a whale surfaces closer than 100 yards, the vessel must reduce speed and alter course to increase distance. During peak whale season from January through March in the channels between Maui and Lana'i, humpbacks are present in large numbers and consistent alertness is required.
How does the Great Barrier Reef Marine Park zone system work for visiting sailors? The Great Barrier Reef Marine Park covers roughly 344,000 square kilometers and uses eight different zone types, each with different permitted activities. Marine National Park zones — the green zones on the official zoning map — prohibit fishing, collecting, and anchoring except in specific designated areas. Large stretches of the reef are accessible to standard boating and anchoring without restriction; navigating the park requires the official GBRMPA zoning maps, available as digital chart overlays compatible with most chartplotters.
What is the best resource for finding MPA regulations before arriving in US waters? MarineCadastre.gov is the authoritative starting point for US waters — the National Viewer tool maps all US MPAs with zone boundaries, zone type descriptions, and links to governing regulations for each protected area. The NOAA Office of National Marine Sanctuaries website (sanctuaries.noaa.gov) provides detailed regulations, zone maps, and vessel guidance for each of the 15 National Marine Sanctuaries. Spending twenty minutes researching before arrival is described as worth the effort to understand which zone type applies.
Why do anchoring restrictions in National Marine Sanctuaries typically apply only to sub-zones rather than the entire protected area? The Florida Keys NMS, for example, covers 2,900 square nautical miles; anchoring restrictions apply within Sanctuary Preservation Areas and Existing Management Areas, which are a subset of that total. The Channel Islands NMS similarly permits anchoring in sand and away from kelp beds, with the no-anchor rule applying only to kelp and rocky areas. This zone-within-zone structure means that treating 'MPA' as a single category causes both over-compliance and under-compliance — reading the actual zone regulations for your specific cruising area is the only correct approach.