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The Tiger Needs the Crab: Bengal Tiger; Fiddler Crab; Sundarban National Park, West Bengal
Sundarban National Park in West Bengal
Where & What is the Sundarban?
This article was inspired by a BBC Two television programme. It was episode 4 of 4 from the series 'Secrets of the Living Planet', called 'Waterworlds', presented by Chris Packham, one of our best wildlife presenters. It drew me in and enthralled me.
The Sundarban National Park is also a Tiger Reserve and a Biosphere Reserve, situated in West Bengal, India. Sundarban is Bengali for ‘beautiful forest’. This national park is part of the Sundarbans on the Ganges Delta, adjacent to the Sundarban Reserve Forest in Bangladesh.
The delta is densely covered by mangroves, indeed it holds the largest mangrove forest in the world. It is also one of the largest reserves for the Bengal Tiger. Home to a variety of wildlife, the Sundarban National Park is a UNESCO World Heritage Site.
Visit the Mangrove Forest
Imagine, if you will, that you are on the edge of mangrove and mud, near the river. You glimpse into the dense forest.
The Tiger; Bengal stripes creep diagonally like a cut-and-staggered picture, flashing orange between the mangroves.
He hunts close to the mud banks of the Ganges, even picking off the occasional human. He rests on the cool mud. He shimmers then fades into mangrove density.
Tiger, Mangrove & Crab
The forest blankets the Ganges Delta. Thick roots reach into the mud, draw nourishment from it, form vast interlocking networks as they spread ever outward.
Their snorkels, mini skyscrapers aiming heaven-ward from the mud, enable them to breathe at high tide.
The mangroves cleanse the Ganges whose clear waters flow on into the sea, a transparent viewfinder exhibiting coral, exotic fish and incomprehensible beauty.
The Fiddler; unbalanced claws play his music as he feeds in the mud, creating burrows, cleansing and tidying as he goes. He fiddles all day, rejecting toxins, bundling them up, leaving piles of rubbish outside his burrow.
An orchestra of crustaceans shares the mud, occupying bi-ways of burrows amid mud-roots of mangroves.
The Fiddler ensures the Mangroves have nourishment for their roots, thereby protecting the forest. The Mangroves cleanse the river which merges into the sea, whilst sheltering wildlife including the Tiger, simultaneously providing his prey.
Connections, cross-connections and interaction between hundreds of organisms and nutrients sustain this wondrous biosphere.
The term ‘ecology of fear’ applies here. Other wildlife use the relative safety of the mangrove to hide from the tiger. The tiger uses it for shelter and sustenance by hunting. The wildlife, therefore, do not expose themselves to certain death by traversing the mud banks so the crab remains relatively safe to go about its daily housework, cleaning up the mud.
Without the crab, the mangroves would perish and so it is an essential contributor to this invaluable biosphere.
Thus the strong, top-of-the-chain Tiger needs the Crab, the menial worker minding his own business.
How cool is that?
Diagram of Fiddler Crab
Fiddler Crab Facts
- They are dimorphic (have two distinct forms),
- the males have one large and one small front claw, the females two small claws,
- the males use their small claw for feeding and
- they use the large one to attract females for mating, to threaten other males and as a weapon when fighting.
- They are sometimes known as the ‘calling crab’, as the waving large claw looks as though it's beckoning,
- they are found on sea beaches, brackish inter-tidal mud flats, lagoons and swamps,
- they shed their shells as they grow, replacing any damaged legs or claws at the same time.
- They exhibit a ‘constant circadian rhythm’ under controlled laboratory conditions, mimicking the ebb and flow of the tide.
- They turn dark in the day and light in the dark.
- They communicate by waving and gesturing with the larger claw,
- the smaller is used for feeding so
- it appears to be playing the larger claw like a violin, or fiddle, hence the name of Fiddler Crab.
The male crab's smaller claw picks up a chunk of sediment from the ground and brings it to the mouth, where its contents are sifted through. After anything edible is salvaged, whether it be algae, microbes, fungus or other decaying detritus, the sediment is replaced in the form of a little ball.
The Fiddler is a detritivore, that is it sifts through the mud to extract its food.
Sediment balls near the entrance to a burrow indicate occupation. So the feeding habits of fiddler crabs play a vital role in the preservation of wetland environments. As they sift through the sands, they aerate the substrate and prevent anaerobic conditions.
Bengal Tiger Bumph
- Found mostly in India, the Bengal Tiger can also be seen in Bangladesh, Nepal, Bhutan, China and Myanmar,
- it is a carnivore,
- using its unique stripe pattern as camouflage and
- focussing its hunting on deer-sized animals such as horses, goats and moose but
- will also try to take down larger animals, such as elephants and bears.
- It is the most numerous of all tiger subspecies with more than 2,500 left in the wild.
- It’s the national animal of both India and Bangladesh and
- is an endangered species.
- Also referred to as the royal Bengal tiger, it has developed a ‘unique characteristic’ of swimming in the saline waters and
- has a tendency to attack and eat humans.
- India’s tiger reserves, created in the 1970s, helped to stabilise numbers, but
- poaching has again put the Bengal at risk.
Mangrove Roots & 'Snorkels'
More about Mangroves
- Mangroves live, at is were, with one foot on land and one in the sea,
- being ‘botanical amphibians’ which occupy a zone of desiccating heat, choking mud, and salt levels that would kill an ordinary plant within hours.
- The mangroves of the forest are among the most productive and biologically complex eco-systems on Earth.
- Birds roost in the canopy, shellfish attach themselves to the roots, and snakes and crocodiles come to hunt.
- Mangroves provide nursery grounds for fish,
- a food source for monkeys, deer, tree-climbing crabs, kangaroos and
- a nectar source for bats and honeybees.
- Those of the Sundarbans are increasingly threatened by sea level rise as a result of climate change.
Mangrove, Mud-bank & River
Protecting the Planet
It seems that the mangroves contribute much in themselves to planet conservation but they in turn need protecting. Throughout the world, some have been destroyed for shrimp farming, industrial building and deforestation. One fifth of the world's mangrove ecosystems have been lost since 1980.
The mangroves not only protect the biosphere but have acted as a buffer against the elements, such as tsunami, cyclones, storm surge, erosion and such like. One set of villagers planted 80,244 saplings to get into the Guinness Book of World Records, creating a kilometre-wide belt of trees. When a tsunami struck, even though much of the land around was flooded, the village itself fared much better.
Apart from the practical rôle the plant plays, the sheer beauty justifies its existence, with the array of flora and fauna it sustains worthy of anyone’s attention. Who would not want to preserve such a place? Who can afford not to do so?
Do we lose the Bengal Tiger and other endangered species or do we make a real effort to safeguard its environment? It’s not the appeal of such an animal that is of paramount importance, it’s the survival of our planet.
The Tiger needs the Crab, the biosphere needs the Mangroves, the planet needs ecosystems to support it. We need them all to sustain life.
Protecting the Environment
Do you think it's important to save such biospheres?
Travel & Education
Does it help to see or find out about such places, for an informed opinion?
© 2017 Ann Carr