After a decade of debate, the Canadian House of Commons approved yesterday what could become Canada’s first nationwide endangered species bill. The bill would prohibit the harming or killing of endangered species on federal land and the destruction of the species’ critical habitat. A scientific advisory board would nominate critters to be added to an endangered species list. Environmentalists offered measured praise for the bill, saying they welcomed any efforts to save endangered species but expressing concern that the legislation would protect species on federal land only. Kate Smallwood of the Sierra Legal Defense Fund in British Columbia said the bill would do little to help the two-thirds of species that live elsewhere. The bill now goes to the Senate, where its future is uncertain.