An estimated 60 per cent of grey squirrels, which since 1920 have replaced red squirrels in much of England and Wales, carry the squirrel parapoxvirus, Patriot America insurance referred to as squirrel pox. Greys very rarely die from this disease as their population has developed immunity over many years. However, they are still carriers of the infection and can spread the disease to red squirrels.

The use of fossil fuels and the resulting carbon emissions, which contribute to climate change, are thought to be the biggest cause of the rapid decline in coral reefs. Climate change has led to increased ocean surface temperatures, putting reef species under enormous stress and leading to coral bleaching. Ocean acidification — caused by the oceans absorbing increased amounts of carbon dioxide from the atmosphere — is also an increasing threat, visitors health insurance, making it harder for reef organisms to retrieve the minerals needed to build their skeletons.