World Endangered Species Day: Biodiverse Goa has lot at stake

Today, on World Endangered Species Day, let's take a look at the reasons for the decreasing population of windowpane oysters
Oyster shells.
Oyster shells.


World Endangered Species Day is observed annually on the third Friday in May. This year, more than anything, the day has special significance for Goan wildlife, especially in the aftermath of the forest fire, the River Mhadei issue and the far-reaching implications of climate change.

Understanding, learning and developing plans for the global conservation of threatened and endangered species are celebrated on this day – a necessary reminder for us Goans that we have much to lose if we do not take concrete actions to preserve our natural heritage. 

Oyster shells.
7 km human chain, to celebrate Mhadei, to be formed on May 20


As we commemorate this important day to create awareness about endangered species, it is more than pertinent to highlight the threat to Goa's important bivalve species of windowpane oysters, which are found in Chiclaim bay.

These oyster species have recently gained attention as a result of a news clip that went viral and featured prominent scientist Dr Baban Ingole from the NIO and the president of the Chicalim Panchayat's Biodiversity Management Committee pleading for protection of these species. 

Besides Chiclaim, windowpane oysters can be found in Sancaole, Siridao and Cacra.

Oyster shells.
River Mhadei through the eyes of an artist in Goa
Windows made of the windowpane oyster (Placuna placenta), are locally called Calva chi Karpa or kovllam-chim zonellam.
Windows made of the windowpane oyster (Placuna placenta), are locally called Calva chi Karpa or kovllam-chim zonellam.Gomantak Times


A retired scientist from NIO, Dr Baban Ingole claims that this area (Chicalim) was once a large bay. However, habitat fragmentation, brought on by various anthropological activities, led to a decrease in the population of windowpane oysters. 

Locals harvest windowpane oysters, scientifically known as Placuna placenta, for their meat, and occasionally discover pearls. Dead windowpane shell trade and pearl trade have a long history, dating back to pre-historic times. 

Oyster shells.
Learn to grow oyster and milky mushrooms in Goa
Some of the ancestral homes have windows made out of oyster shells.
Some of the ancestral homes have windows made out of oyster shells. Photo: Venita Gomes

The use of windowpane oysters was seen during the Portuguese occupation of Goa, when these shells were used instead of glass to decorate window frames hence the name windowpane oyster.

According to Dr Ingole, pearls found in these shells were prized, not only as decoration, but also for their therapeutic qualities. 

These bivalves' shells were also used to make jewellery and other handicrafts, including lamp shades... but all this is part of history now, says Dr Ingole.

Oyster shells.
‘Kaddio boddio’ keeps mouths salivating during feasts in Goa


Once found in large numbers, these oysters have seen a decline in their population due to anthropogenic activities like shipyard building, water pollution and unrestricted fishing, mining and barge movement, etc. 

Despite being declared a Schedule VI species under the Wildlife Protection Act, and restriction by the Goa State Biodiversity Board, exploitation of these important and endangered species has not stopped.

Oyster shells.
Who knew that shells could be used to make windows!

Members of the local biodiversity committee are working to raise awareness of the need to conserve these significant species. However, these requests, caution and rules are causing a lot of concern among the populace. 

On the weekends, they still swarm the area in search of windowpane oysters and clams. These bivalves take almost 4 to 5 years to reach maturity.

The lockdown in the year 2020 and the cessation of mining and barge traffic have likely contributed to some degree to the resurgence of this species. 

Oyster shells.
Local community suffer as Oyster, Clams found missing from Chicalim Bay


David Robinson and the Endangered Species Coalition established this day of activism because many species were disappearing.

Based on analysis and recommendations received from its expert members, the International Union for Conservation of Nature (IUCN) determines whether each species is endangered, threatened, vulnerable, critically endangered or extinct. 

The world's most complete database of information on the extinction-risk status of a plant, animal and fungal species can be found in the IUCN Red List of Threatened Species. The most recent data available on the website shows that 150388 species have been evaluated in total, of which 42,108 are threatened.

Oyster shells.
Earth Day: Guess the names of Goa’s wildlife sanctuaries


One of the world's most vital mega-diversity nations is India. To protect species diversity, several laws have been passed, including the Biological Diversity Act of 2002, the Forest Conservation Act of 1980, the Environment Protection Act of 1986 and the Wildlife Protection Act of 1972.

However, the extent of our greed is inversely proportionate to the efforts we are making in the protection of our environment.

Oyster shells.
How many of these appetising jackfruit dishes have you eaten in Goa?


Over the past few years, researchers, activists and NGOs have worked to preserve our fragile environment through research, education campaigns and conservation efforts.

As the allure of development has captured our good sense and conscience, we have become deaf to this group of people. 

Important local species of fungi, birds, wild animals and rice have all disappeared. We frequently discuss charismatic tigers, elephants and other large mammals, but we hardly ever discuss the lesser-known plants and animals that are also a part of our biodiversity.

(Asavari Kulkarni is an environmentalist and covers topics on environment and social aspects)

Your Gateway to Goa, India

The Gomantak Times app is the best way to stay informed on anything happening in Goa. From breaking news to the top 10 restaurants to visit, GT helps you navigate your time in Goa.

Download the Gomantak Times app on your Android or IOS device.

Related Stories

No stories found.
Goa News in English on Gomantak Times