The islands that went from whale hunting to whale watching

By releasing fish into the Chicago River, the city of Chicago aims to help clean up its ecosystem, as the fish hopefully will eat the river's excess algae.

The Seal Mammal Research Unit at the University of St. Andrews is recruiting and tagging pinnipeds to gather details on ocean conductivity, temperature and depth, collectively called “CTD profiles.” When tagged animals surface, the data they’ve collected are relayed to a global satellite system, decoded by computers, and disseminated to researchers.

Overall, Cambodia is a relatively poor country whose residents don't own much. Norwegian hotel owners in the city of Krong Siem Reap urge their Cambodian staff to be more in charge of making their own decisions by making them co-owners of the hotel, an act that forced them to have more confidence and critical thinking skills.

Warming water has led to the collapse of coral reef systems in the western Indian Ocean, essential to fisheries, protecting shorelines, and reducing beach erosion and sea-level rise. Marine scientists from Nature Seychelles, as part of an international project to protect and restore the reefs, are promoting varieties of coral that they have found to be resistant to the rise in temperature.

Geography and climate change challenge the viability of sea-level cities in Vietnam, but architects, researchers, and urban planners work together to find creative solutions. One architect in Ho Chi Minh City designed green roofs to absorb the rainwater that causes floods.

Farmers in Vietnam face rising sea levels but rejected the city's water engineering projects. They prefer gradual measures to cope with climate change so scientists have allowed the farmers to steer the conversation.

Louisiana and Vietnam both need affordable solutions to rising sea levels. Leaders from Vietnam visited Louisiana to compare ideas.

The World Conservation Union estimates that 40 percent of the more than 40,000 species it tracks on its Red List are close to extinction and this problem requires humans to change their behavior to fix it. Rare’s the Pride Campaign uses social marketing to attract attention and communicate the conservation message between local communities and government entities. The Pride Campaign has been replicated around the world for different conservation efforts to protect biodiversity.

New water management technology implemented along the Columbia has significantly helped the fish population - specifically salmon - return to healthy numbers and has restored much of the community and industry that revolves around the river, including for native peoples.

Tottenville, on Staten Island, will get oyster-friendly breakwaters and a dune system as part of post-Sandy rebuilding efforts. The oysters will help revive the ecosystem and sustain the long-term fishing economy.