6 danger , a change in our land use , an increasing amount of pests , lake and sea warming , and more droughts and floods . In fact , because of global warming 70 species of native plants are likely to be at risk of extinction this century . In the past , our native species have been able to adapt by shifting their ranges . But now , in places such as Manawatu , the landscape has changed so much due to humans ( with our removing of forests , building of roads and cities , and destroying of wetlands ) that they are unable to do this any more . The rising temperatures will also benefit pests such as rats and hedgehogs , as the previously harsh winters were able to limit their impact . The rising climate however will lead to milder winters allowing these pests to invade and flourish , along with their disease and weed counterparts , meaning that our species that are already threatened by them , will find themselves even more threatened .
To be more specific I shall go into several examples :
1 . Marine birds . With the changing ocean currents and warmer seas , food chains and organisms in the sea will be disrupted , meaning that our marine birds will become deprived of food . Fish that used to swim to New Zealand and live in our cold water coral reefs may leave and die due to the rising ocean temperatures causing distributional changes in food supplies , leaving many of our endangered birds such as the antipodean albatross and the eastern rockhopper penguin to either have to resort to eating other organisms that they are not used to catching and eating , or die .
2 . Still staying on the topic of the ocean , we have the problem of ocean acidification . While it is normal for a main greenhouse gas carbon dioxide to get incorporated into rain and then fall , dissolving limestone and creating caves . When excess CO 2 enters the sea it can do a lot of damage . When CO 2 gets combined with water it becomes carbonic acid ( H 2CO 3 ) which can dissolve the shells of marine crustaceans and animals , harm phytoplankton ( which is essential when it comes to the marine food chain ) and harm our slow growing cold water corals which are important habitats to many organisms such as mussels , oysters , squid , kina and crayfish . The harm caused here then affects fish higher up the food chain such as commercial fish , which then affects New Zealand ’ s fishing industry .
3 . River species can also be affected along with those that live in the ocean . Twenty five of New Zealand ’ s native birds species nest on braided river beds and these include some highly threatened species such as the black billed gull , wrybill and the banded dotterel . Along with the threats from the weeds thriving in the warming climate , introduced predators and irrigation schemes , the increased floods caused by climate change are an extreme threat when it comes to