Nanda Lake Wildlife Reserve: A Mapped Analysis of Goa's Significant Ramsar Wetland Habitat

Nanda Lake is best known as Goa's only internationally recognized Ramsar wetland, a status that highlights its importance despite its very small size. The lake is especially recognized for its bird diversity, supporting a mix of resident waterbirds such as red-wattled lapwing, black-headed ibis, bronze-winged jacana, brahminy kite, common kingfisher, wire-tailed swallow, intermediate egret, little cormorant, and lesser whistling duck. Beyond birds, the wetland is also valued for its broader freshwater biodiversity, including dragonflies, butterflies, fish such as Lepidocephalichthys thermalis, and mammals such as the smooth-coated otter, which together reflect the richness of even small lowland wetlands in the Western Ghats region.

Nanda Lake's modern conservation history is relatively recent, reflecting both its ecological condition and the evolving policy framework for wetland protection in India.

The lake was officially notified as a wetland by the Government of India in 2021 under the Wetland (Conservation and Management) Rules, 2017, marking the first step toward formal recognition of its habitat values. Following this notification, it was designated as a Ramsar wetland site during the 2022 cycle of the Ramsar Convention, with the formal declaration recorded on 8 June 2022 and assigned reference number 2471.

The Ramsar designation made Nanda Lake the first and, to date, the only Ramsar site in Goa, drawing attention to the importance of protecting small freshwater systems within India's coastal states. Its recognition also aligns with India's broader effort to expand its network of internationally catalogued wetlands, moving beyond large, well-known sites to include ecologically meaningful smaller habitats scattered across the country.

Nanda Lake is set within a typical Goan landscape of laterite hills, low plateaus, and narrow river valleys that descend from the Western Ghats toward the Arabian Sea. The terrain around the lake is shaped by intense monsoon rainfall, which feeds both permanent water bodies and seasonal streams during the wet season.

The lake itself is a small, still freshwater body surrounded by vegetation that transitions between aquatic, semi-aquatic, and dry-land communities characteristic of the Konkan coast. Open water margins, marshy fringes, and adjacent scrubland create a layered habitat structure, while the broader watershed includes forested patches and agricultural land typical of inland Goa.

Because of its location in a region heavily modified by human activity, Nanda Lake's surviving natural landforms and shoreline vegetation have heightened ecological significance, offering one of the few intact freshwater wetland landscapes in its part of Goa.

As a freshwater wetland in coastal western India, Nanda Lake supports a varied ecological community across aquatic, semi-aquatic, and shoreline zones. The habitat structure includes open water, emergent vegetation, marshy edges, and surrounding wooded and scrubby margins, which together create transitional environments favored by a wide range of species.

The wetland reflects the broader ecological traits of lowland Goan freshwater systems, where biodiversity depends heavily on the interface between water and land during and after the monsoon season. The lake functions as a refuge for organisms that rely on standing freshwater in an otherwise heavily altered coastal landscape.

Dragonflies and damselflies are particularly well represented around Nanda Lake, with species such as Brachythemis contaminata, Bradinopyga geminata, Ceriagrion cerinorubellum, Crocothemis servilia, Libellula needhami, Neurothemis fulvia, Neurothemis tullia, Pseudagrion microcephalum, and Rhyothemis variegata recorded here. Butterflies, fish, amphibians, and aquatic invertebrates add further ecological complexity.

Nanda Lake is most noted for its birdlife, which includes a mix of resident and visiting waterbirds, raptors, and woodland species associated with the wetland's fringe habitats. Among the regularly noted species are red-wattled lapwing, black-headed ibis, bronze-winged jacana, brahminy kite, common kingfisher, wire-tailed swallow, intermediate egret, little cormorant, and lesser whistling duck.

Additional bird records reflect the diversity of habitats around the lake and include purple heron, cinnamon bittern, black-crowned night heron, glossy ibis, black-headed ibis, Indian pond heron, little egret, common snipe, small pratincole, river tern, yellow wagtail, white-browed wagtail, striated heron, common kingfisher, white-throated kingfisher, blue-tailed bee-eater, green bee-eater, Indian golden oriole, black drongo, rufous-tailed fantail, ashy prinia, jungle prinia, common tailorbird, red-whiskered bulbul, red-vented bulbul, white-browed bulbul, plain prinia, clamorous reed warbler, common myna, jungle myna, Indian robin, oriental magpie-robin, and spotted dove.

The mammal smooth-coated otter has been recorded at the site, indicating the wetland's ecological completeness as a freshwater system. Fish such as Lepidocephalichthys thermalis contribute to the aquatic food web. Together, the recorded species highlight the lake's importance as a compact biodiversity hotspot within a densely populated coastal state.

Nanda Lake's principal conservation significance lies in being Goa's only Ramsar site, placing it within a global framework for wetland protection and management. The Ramsar designation, with reference number 2471, recognizes the lake's value for waterbird habitat, biodiversity, hydrological function, and ecological character.

The lake was notified as a wetland by the Government of India in 2021 under the Wetland (Conservation and Management) Rules, 2017, giving it formal national-level protection status. This regulatory framework requires conservation and management planning, monitoring, and restriction of activities that could degrade the wetland.

Conservation interest in Nanda Lake also extends to its role as a demonstration of the value of small freshwater wetlands in India's coastal states. In a region where most natural wetlands have been lost or degraded, Nanda Lake represents a surviving reference ecosystem, supporting fish, invertebrates, amphibians, birds, and mammals and contributing to groundwater recharge and local climate moderation.

Nanda Lake is Goa's sole Ramsar wetland site, recognized internationally under the Ramsar Convention in 2022 and notified nationally under India's 2017 wetland rules.

It stands out for combining a very small physical footprint with strong ecological output, supporting a recorded avifauna that includes red-wattled lapwing, black-headed ibis, bronze-winged jacana, brahminy kite, common kingfisher, wire-tailed swallow, intermediate egret, little cormorant, and lesser whistling duck.

The wetland also harbors smooth-coated otter and a notable assemblage of dragonflies, butterflies, and freshwater fish, reinforcing its profile as a compact biodiversity habitat within the Western coastal landscape of Goa.

Nanda Lake's character shifts significantly with the monsoon cycle that defines western India. The wet season, driven by the southwest monsoon, brings heavy rainfall that swells the lake and surrounding water bodies, intensifies vegetation growth, and increases activity among amphibians, dragonflies, and waterbirds.

The cooler and drier months that follow the monsoon are typically the most comfortable for observation, when water levels stabilize and bird activity remains high, with both resident and wintering species being present. This period is often considered favorable for viewing shorebirds, waders, and waterfowl on the lake's margins.