Blue penguin numbers are declining for several reasons: 1. Oil leaks from humans are polluting the oceans where blue penguins live. 2. They are preyed upon by predators like cats, foxes, and New Zealand fur seals. 3. Many penguins are killed by vehicles when trying to cross roads near their coastal habitats at night. Over 100 penguins have been killed on roads in New Zealand in the last five years. Their declining numbers affects other species in the ecosystem like small fish populations. Conservation efforts are needed to protect the blue penguins and prevent their extinction.