Green Tiger Prawn

Penaeus semisulcatus

කුරුටු ඉස්සා

Penaeus semisulcatus, commonly known as the Green Tiger Prawn, is a commercially valuable shrimp species found in tropical and subtropical waters. Known for its striking greenish-brown coloration and rapid growth rate, this species is a key player in the global shrimp farming industry. It is widely harvested for human consumption and plays an essential role in marine and estuarine ecosystems.

Physical Characteristics

The Green Tiger Prawn has a robust, elongated body covered in a hard exoskeleton. It is distinguished by its greenish or olive-brown body with dark transverse bands, giving it a tiger-like appearance. The rostrum (a pointed extension of the carapace) is long and serrated, and the species has well-developed walking and swimming legs. Adults can grow up to 30 cm in length, making them one of the larger prawn species.

Habitat and Distribution

Penaeus semisulcatus is widely distributed across the Indo-Pacific region, including the coasts of the Indian Ocean, the Red Sea, and the western Pacific. It primarily inhabits sandy or muddy bottoms in coastal waters, estuaries, and mangrove areas at depths of 10–90 meters. Juveniles are often found in shallow, brackish environments before migrating to deeper waters as they mature.

Diet and Feeding Behavior

The Green Tiger Prawn is an opportunistic omnivore, feeding on detritus, small crustaceans, mollusks, and plant matter. It uses its specialized appendages to sift through the seabed and capture prey. Its scavenging nature plays a crucial role in maintaining the balance of marine ecosystems by recycling organic material.

Defensive Adaptations

Although lacking strong physical defenses, the Green Tiger Prawn relies on its agility and camouflage to evade predators. Its body coloration blends with the seafloor, making it less visible to predators. Additionally, it exhibits rapid tail-flipping movements (known as the caridoid escape reaction) to escape from threats.

Reproduction and Life Cycle

Like other penaeid prawns, Penaeus semisulcatus follows a complex life cycle that includes several larval stages before reaching adulthood. Spawning occurs in offshore waters, where females release thousands of eggs that hatch into free-swimming larvae. The larvae go through multiple developmental phases before settling in estuarine habitats as juveniles. As they grow, they migrate back to deeper waters to continue the cycle.

Ecological Role

Penaeus semisulcatus, the Green Tiger Prawn, plays a vital role in marine ecosystems. It serves as both predator and prey, helping maintain food web balance. By burrowing in seabeds, it aids in sediment oxygenation and nutrient recycling. Juveniles thrive in estuaries and mangroves, supporting biodiversity and carbon sequestration. As a bioindicator, its population health reflects environmental conditions. Protecting this species is essential for ecosystem stability and sustainable fisheries

Conservation Status

Although not currently listed as endangered, Penaeus semisulcatus faces threats from overfishing, habitat degradation, and climate change. Sustainable aquaculture practices, habitat restoration, and fisheries management are essential to maintaining healthy populations.

Conclusion

The Green Tiger Prawn (Penaeus semisulcatus) is an ecologically and economically significant species. Its role in marine ecosystems, coupled with its commercial value, highlights the importance of responsible fisheries management. Conservation efforts and sustainable shrimp farming practices will be crucial in ensuring the long-term survival of this valuable crustacean.