Habitat Fragmentation — Metapopulation

Parameters

N patches: 20 Connectivity c: 0.30 Extinction rate e: 0.15 Colonization rate c_m: 0.4 Rescue effect strength: 0.5

Occupied patches—

Fraction occupied—

Equilibrium p*—

StatusRunning

Levins metapopulation:
dp/dt = c_m·p·(1−p) − e·p
Equilibrium: p* = 1 − e/c_m
Rescue effect: immigration reduces local extinction. Fragmentation reduces connectivity → more extinctions. SLOSS debate: few large vs many small patches.