Cleveland - Opponents of a high-pressure natural gas pipeline expected to be built across the northern half of Ohio are clinging to the wings of a furry flier, the northern long-eared bat, in their efforts to at least delay the $2bn project.The existence of the threatened species remains one of the impediments the partnership between Houston-based Spectra Energy and Detroit's DTE Energy face before receiving expected approval to build the 410km long Nexus pipeline capable of transporting the gas from the shale fields of Appalachia into Michigan and Ontario, Canada.Nexus cleared a big hurdle in November when the Federal Energy Regulatory Commission issued an environmental impact statement that found no problems with the company's proposed route. Nexus now awaits the Commission's approval to begin construction, a step that could be delayed when one of its three Commission members resigned last week.Opponents of the project in Ohio's Summit and Medina counties aren't backing down from a fight that began with efforts to get the pipeline rerouted away from homes and businesses to less populated areas. The Commission ruled in the impact statement that alternative routes proposed by the city of Green in southern Summit County held no environmental advantages over the one proposed by Nexus. The existence of northern long-eared bats, classified as a threatened species by the US Fish and Wildlife Service, along the proposed route means Nexus isn't completely out of the woods. The bats live in caves and other sheltered spots during winter and nest in trees during spring and summer. Its threatened status means trees in their habitats are not supposed to be felled between April 1 and September 30.Pipeline opponents hope the bats will cause further delays if the Commission doesn't allow the company to fell trees after March 31.