Seahorses depend entirely on seagrass meadows and coral reefs for habitat — the global decline of these ecosystems drives population collapse and removes the habitat structure seahorses need for welfare and survival.
Seahorses in degraded seagrass habitats face a welfare crisis of environmental inadequacy — without holdfast structures, they cannot anchor against currents and are swept from their territories. This is not simply a population problem but an individual welfare issue: each seahorse displaced from degraded habitat experiences the chronic stress of an environment that no longer provides the structural security its biology requires. Marine protected areas that preserve seagrass provide genuine welfare benefit by restoring the conditions in which seahorses can function normally.