Asian carp were introduced in America to help control certain plant species, but are thought to have an adverse effect on food cycles.
Bee colonies have reportedly collapsed at higher than normal rates in recent history. Colony Collapse Disorder has already caused agricultural and environmental problems.
Sustained higher water temperatures have caused coral in the Great Barrier Reef to bleach. This can cause the coral to starve and become diseased, which has huge implications for the reef.
In an attempt to sustain National Parks, some are looking towards privatizing parks and federally-owned lands in order to relieve the strain on state and local governments' budgets and keep the parks open.
Solid waste management has become controversial in some regions where private companies receive trash from out of state clients for disposal.
While some believe zoos are a way for people to learn more about animals from other continents and keeping animals in captivity may allow them to live longer lives since they are not forced to survive in the wild, others believe keeping animals in captivity in zoos in different continents and climates that they are used to is a form of animal cruelty.