Explanation:

The recent oil spill was not the first incidence of its kind and there have been cases in past too.

These bacteria convert the oil sludge into carbon Dioxide and water (oil is basically Hydrocarbon only).
When an oil slick from a large oil spill reaches the beach, the oil coats and clings to every rock and grain of sand. If the oil washes into coastal marshes, mangrove forests or other wetlands, fibrous plants and grasses absorb the oil, which can damage the plants and make the whole area unsuitable as wildlife habitat.
Oil spills frequently kill marine mammals such as whales, dolphins, seals and sea otters. The deadly damage can take several forms. The oil sometimes clogs the blow holes of whales and dolphins, making it impossible for the animals to breathe properly and disrupting their ability to communicate.
Oil coats the fur of otters and seals, leaving them vulnerable to hypothermia.
Even when marine mammals escape the immediate effects, an oil spill can cause damage by contaminating their food supply. Marine mammals that eat fish or other food that has been exposed to an oil spill may be poisoned by the oil and die or can experience other problems.