Feather Caulerpa

Overview

Feather Caulerpa (Caulerpa taxifolia) is a fast-growing green marine alga native to tropical waters across the Pacific, Indian, and Atlantic Oceans. While it exists as a harmless native species in many tropical regions, a specific, cold-tolerant strain has become a notorious invasive species in the Mediterranean Sea and other temperate areas after being introduced via the aquarium trade.

Appearance

This alga is characterized by bright green, feather-like fronds that rise from creeping, horizontal stems known as stolons. These fronds typically range from 3 to 60 cm in height, depending on light availability and depth. The leaf-like branchlets are attached in opposite pairs along the central axis, are constricted at their base, and curve upward, tapering toward the tips. The entire organism is a single, large, multinucleate cell.

Biology & behavior

Caulerpa taxifolia is highly resilient and capable of colonizing a wide variety of substrates, including rock, sand, mud, and seagrass beds. It reproduces primarily through vegetative fragmentation; even tiny pieces of the plant can drift with currents or be transported by human activity—such as boat anchors or fishing gear—to establish new, dense colonies. The species produces toxic metabolites, including caulerpenyne, which deter many local herbivores and contribute to its ability to outcompete native vegetation and reduce biodiversity in invaded ecosystems.