Major environmental groups in Ecuador, led by Fundacion Natura, banded together yesterday to announce their official opposition to a billion-dollar pipeline project that would double the country’s crude oil output. Ecuador’s Energy Ministry is expected to decide whether to grant the project an environmental permit early in June. The pipeline would go straight through the Mindo ecological reserve, an area 16 miles northwest of Quito that provides important bird habitat. International groups Greenpeace and Amazon Watch sent a letter this week to financiers J.P. Morgan Chase and Citigroup objecting to their involvement in the project.