Suchindrum Theroor Wetland complex is part of the Suchindrum-Theroor Manakudi Conservation Reserve. It is declared an Important Bird Area and lies at the southern tip of the Central Asian flyway of migratory birds. The wetlands have two mounds, each one at Suchindram and Theroor. It was formed for birds\' nesting purposes and it attracts thousands of birds every year. The total population dependent upon Theroor is about 10,500 and 75% of the population’s livelihood hinges on agriculture which in turn is dependent upon the water released from the Theroor tank. The total population dependent upon Suchindram is about 25, 000 and 75% of the population’s livelihood hinges on agriculture which in turn is dependent upon the water released from the Suchindram tank. This is a man-made, inland Tank and is perennial. The history of this wetland complex is age-old, but it is known that kings contributed a great deal to the irrigation facilities. Copper plate inscriptions from the 9th century mention Pasumkulam, Venchikulam, Nedumarthukulam, Perumkulam, Elemchikulam and Konadunkulam. These tanks were located in Tiruneveli district on the northeast of the Gulf of Mannar. On the south and southwest, the wetland complex is bounded by the Indian Ocean and the Arabian Sea. Kanyakumari district receives rainfall from both the southwest and the northeast monsoons. The southwest monsoon starts in June and ends in September, while the northeast monsoon extends from October to the middle of December. As mentioned above, the wetland complex forms part of the Important Bird and Biodiversity Area (IBA) and hence part of the BirdLife International Data Zone. The wetland complex lies at the intermittent point of kodaiyar river drainage system, where water stored at Perunchanidam, Pechipparai and Kodaiyar dams are released into the channel which drains thousands of ponds. While Theroor tank receives water from thovalai channel, Suchindram tank receives water from Pazhaiyar river Channel. Around 250 species of birds have been recorded in the area, of which 53 are migratory, 12 endemic, and 4 threatened.

A wetland should be considered internationally important if it contains a representative, rare, or unique example of a natural or near-natural wetland type found within the appropriate biogeographic region.

A wetland should be considered internationally important if it supports vulnerable, endangered, or critically endangered species or threatened ecological communities.

A wetland should be considered internationally important if it supports populations of plant and/or animal species important for maintaining the biological diversity of a particular biogeographic region.

A wetland should be considered internationally important if it supports plant and/or animal species at a critical stage in their life cycles, or provides refuge during adverse conditions.

A wetland should be considered internationally important if it regularly supports 20,000 or more waterbirds.

A wetland should be considered internationally important if it regularly supports 1% of the individuals in a population of one species or subspecies of waterbird.

A wetland should be considered internationally important if it supports a significant proportion of indigenous fish subspecies, species or families, life-history stages, species interactions and/or populations that are representative of wetland benefits and/or values and thereby contributes to global biological diversity.

A wetland should be considered internationally important if it is an important source of food for fishes, spawning ground, nursery and/or migration path on which fish stocks, either within the wetland or elsewhere, depend.

A wetland should be considered internationally important if it regularly supports 1% of the individuals in a population of one species or subspecies of wetland-dependent nonavian animal species.