Protecting our mud crab

Biodiversity is the ‘natural capital’ that we need to protect and use wisely, underscores Dr. Don Macintosh, pointing out that habitat and biodiversity loss and pollution are the widespread consequences of human activities. These impact on human health, food security and livelihoods while climate change and extreme weather patterns are adding to the threats faced by all natural ecosystems.

Dwelling on what the ‘ecosystem approach’ is, he says it is astrategy for integrated management of land, water and living resources that promotes conservation and sustainable use in an equitable way.

Picking out the coastlines and seas within tropical Asia which are among the most productive and biodiversity-rich in the world, Dr. Macintosh explains that coral reefs and sea-grass beds provide the primary production and habitat needs of countless marine animal species, while mangrove ecosystems sup- port hundreds of animal and plant species from diverse origins (marine, intertidal and terrestrial).

“Conserving these valuable, but fragile ecosystems and the biodiversity they support is made very challenging by a number of factors. They include the high levels of exploitation of aquatic species by coastal fishing communities and commercial fisheries and development pressures to increasingly urbanise and industrialise Asia’s coastal zones.”

Without sustainable (ecosystem-based) management, there is over- exploitation of natural resources; unplanned and unregulated coastal development; weak institutional responsibilities and poor governance which lead to habitat degradation, erosion, pollution, aquatic diseases and loss of valuable species, fisheries and livelihoods, it is learnt.

Here, Dr. Macintosh delves deep into the mangroves and picks up the mud-crab citing the case study of the ‘Sri Lankan jumbo crab’. Moving among mangroves, inshore and offshore habitats during its life history, which includes phases as a planktonic, crawling, burrowing and swimming organism, this iconic and valuable crustacean is severely threatened by habitat loss and over-fishing.

The mud-crab is the most mangrove-dependent fisheries resource supporting local livelihoods, but is severely over-fished, according to him.

“Immensely important to the food and livelihood security of millions of coastal- and river- dwelling people globally and especially across Asia, the commercial species are part of complex food webs. However, they have been heavily impacted by over-fishing, habitat loss or degradation and pollution,” laments this expert.

This is why Dr. Macintosh is urging a “common vision” for healthy coastal ecosystems, to bring about a more prosperous and secure future for coastal communities.

Otherwise, for Sri Lankans a sumptuous, finger-licking good crab curry may also become just a dream.