The ocean has also contributed significantly to the development and economy of the countries around it. Besides its major transatlantic transportation and communication routes, the Atlantic offers abundant petroleum deposits in the sedimentary rocks of the continental shelves and the world's richest fishing resources, especially in the waters covering the shelves. The major species of fish caught are cod, haddock, hake, herring, and mackerel. The most productive areas include the Grand Banks of Newfoundland, the shelf area off Nova Scotia, Georges Bank off Cape Cod, the Bahama Banks, the waters around Iceland, the Irish Sea, the Dogger Bank of the North Sea, and the Falkland Banks. Eel, lobster, and whales have also been taken in great quantities. All these factors, taken together, tremendously enhance the Atlantic's great commercial value. Because of the threats to the ocean environment presented by oil spills, marine debris, and the incineration of toxic wastes at sea, various international treaties exist to reduce some forms of pollution.