Arabian Sea

The Arabian Sea

The Arabian Sea, also known as Sindhu Sagar in Hindi and baḥr al-ʿarab in Arabic, is a major sea in the northwestern Indian Ocean. The name “Arabian Sea” refers to the historical and geographical influence of the Arab world on this body of water. Throughout history, the sea has also been known by various other names, including the Erythraean Sea, the Indian Sea, and the Persian Sea.

Geographical Location and Adjacent Countries

The Arabian Sea is located in the northwestern Indian Ocean and is bordered by several countries. To the west, it is bordered by the Arabian Peninsula, the Gulf of Aden, and the Guardafu Channel. To the northwest, it is bordered by the Gulf of Oman and Iran, to the north by Pakistan, to the east by India, and to the southeast by the Laccadive Sea and the Maldives. The largest river that flows into the sea is the Indus.

Major Cities on the Arabian Sea

Some of the major cities on the Arabian Sea coast include Mumbai and Kochi in India, Karachi in Pakistan, Muscat in Oman, and Aden in Yemen. These cities are not only important for regional economies, but also for international trade due to their strategic locations.

Habitat and Biodiversity

The Arabian Sea is one of the most productive marine ecosystems in the world, partly due to the strong upwelling of nutrient-rich water. This phenomenon creates a rich biodiversity, including a large number of fish species. The sea is home to pelagic fish such as tuna, sardines, swordfish, wahoo, sharks, lancets, and moonfish.

Rivers Flowing into the Sea

The major rivers flowing into the Arabian Sea are the Indus and the Narmada. These rivers bring large amounts of sediment and nutrients to the sea, contributing to the high productivity of the ecosystem.

Important Fish Species

Fisheries in the Arabian Sea are of great importance to the local economies. Important commercial fish species include tuna, sardines and swordfish. These species are not only important to the fisheries, but also to the aquarium trade, although most commercial fishing is for consumption.

Important Aquarium-Suitable Fish Species

The Arabian Sea is home to a rich biodiversity, including many fish species that are popular in the aquarium trade. Here are some of the most common fish species from the Arabian Sea that are often offered as aquarium fish:

1. Anemonefish:
   Amphiprion ocellaris: This fish is known for its symbiotic relationship with sea anemones and is one of the most popular aquarium fish.
   Amphiprion percula: Almost identical in appearance to the Amphiprion ocellaris, but with slightly different color patterns.
2. Angelfish:
   Pomacanthus asfur: This fish is not reef safe and can grow up to 40 cm. Pomacanthus semicirculatus: Known for its striking color changes during growth.
3. Butterflyfish:
   Chaetodon lunula: This fish has a complex color pattern and is usually yellow with a dark saddle and a black and white mask Chelmon rostratus: Known for its long snout and silver body with gold stripes.
4. Larts:
   Pseudocheilinus hexataenia: A small, semi-aggressive fish that is often added to control pests such as flatworms.
   Macropharyngodon meleagris: A reef-safe fish known for its beautiful color patterns.
5. Gobies:
   Cryptocentrus cinctus: This fish can form a symbiotic relationship with pistol shrimp. Elacatinus oceanops: A cleaner fish that sometimes eats larger parasites from other fish.
6. Surgeonfish:
   Zebrasoma flavescens: A very popular reef safe fish that is known for its bright yellow color.
   Paracanthurus hepatus: Also known as the “Dory” fish, this fish is very susceptible to Cryptocaryon irritans.

These fish species are popular in the aquarium trade because of their striking colors, interesting behavior, and relatively easy care. However, it is important to know that some of these fish have specific care requirements and are not always suitable for beginners.

Different Habitat

The Arabian Sea has several habitats, each with unique characteristics:

• Coastal: These areas are rich in mangroves and coral reefs, especially along the coasts of Pakistan and India. Mangroves provide important habitat for young fish and other marine organisms.
• Deep Sea: The deeper parts of the Arabian Sea, such as the Arabian and Somali basins, are rich in deep-sea fish and other organisms that have adapted to the high pressure and low temperatures.
• Upwelling Areas: These areas, especially along the coasts of Oman and Yemen, are particularly productive due to the upwelling of nutrient-rich water. This phenomenon supports large populations of plankton, which in turn provide food for larger fish species.

Water Circulation

The water circulation in the Arabian Sea is strongly influenced by the monsoon winds, which change direction seasonally. In summer, southwesterly monsoon winds cause upwelling along the coast of Oman, while northeasterly monsoon winds cause a decrease in upwelling in winter.

Water Values

The salinity of the water in the Arabian Sea varies, but averages around 35 PSU, corresponding to a specific gravity (SG) of about 1.026. The surface water temperature ranges from 25°C in winter to 29°C in summer. The deeper water layers are colder and have lower oxygen concentrations, sometimes leading to hypoxic conditions.

Conclusion

The Arabian Sea is a complex and dynamic ecosystem with rich biodiversity and diverse habitats. The sea plays a crucial role in regional economies through fishing and its strategic location for international shipping routes. However, climate change and human activities are having a significant impact on this fragile ecosystem, requiring continuous monitoring and management to maintain biodiversity and marine productivity.

Author

John de Lange

Image copyright

NormanEinstein, Ras67 – CC BY-SA 3.0