Marine Protected Area Size Calculator

Estimate minimum MPA size from species home range, viable population targets, species-area relationships, and protection level requirements.

Inputs

Focal species home range (km²)

Target species count

Min viable population (MVP)

Population density (/km²)

Connectivity buffer (%)

Protection level (1-3)

Tab to move between fields

Results

Recommended MPA area (km²)

16,900

Core area needed (km²)10,000

Area (hectares)1,690,000

Area (nmi²)4,928.04

Approx perimeter (km)460.8

Est. annual patrol cost ($)$46,084.00

How to Use This Calculator

Enter the target species home range or area requirements in km².
Set the number of core no-take zones and desired buffer zone width in km.
Input connectivity requirements between MPA units if designing a network.
Review the minimum MPA size and total protected area in km².
Compare to the 30×30 global conservation target and regional management plans.

How the result changes with Target species count

Target species count	Recommended MPA area (km²)
101	175,862,077.69
351	25,651,642,017.69
650	301,675,562,500
900	1,108,809,000,000

What each input means

Focal species home range (km²): Home range of the largest focal species to be protected. This sets a minimum core area.
Target species count: Number of species the MPA should sustain, used in species-area relationship.
Min viable population (MVP): Minimum number of individuals needed for long-term population viability (commonly 500-5000).
Population density (/km²): Average density of the focal species in suitable habitat (individuals per km²).
Connectivity buffer (%): Additional area for larval dispersal corridors, edge effects, and habitat connectivity (typically 20-50%).
Protection level (1-3): 1 = partial use, 2 = high protection, 3 = strict no-take. Higher protection requires less total area.

What each result means

Recommended MPA area (km²): Total recommended MPA area accounting for connectivity buffer and protection level.
Core area needed (km²): Minimum core habitat area before buffer and protection adjustments.
Area (hectares): Recommended area in hectares.
Area (nmi²): Recommended area in square nautical miles.
Approx perimeter (km): Estimated boundary length assuming circular MPA shape.
Est. annual patrol cost ($): Rough annual enforcement cost estimate based on perimeter length.

How this is calculated

Worked example, using the default values

Identify Input Parameters
4 parameters
Focal species home range (km²) = 50, Target species count = 10, Min viable population (MVP) = 500, Population density (/km²) = 2 = 6 input(s) provided
Calculate Recommended MPA area
Recommended MPA area = totalAreaKm2 * protectionMultiplier
16900 = 16900
Calculate Core area needed
Core area needed = max(areaForPopulation, areaForDiversity, homeRangeKm2)
10000 = 10000
Calculate Area
Area = effectiveAreaKm2 * 100
1690000 = 1690000

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