BODO, Nigeria  Big oil spills are no longer news in this vast, tropical land. The Niger Delta, where the wealth underground is out of all proportion with the poverty on the surface, has endured the equivalent of the Exxon Valdez spill every year for 50 years by some estimates. The oil pours out nearly every week, and some swamps are long since lifeless.

Perhaps no place on earth has been as battered by oil, experts say, leaving residents here astonished at the nonstop attention paid to the gusher half a world away in the Gulf of Mexico. It was only a few weeks ago, they say, that a burst pipe belonging to Royal Dutch Shell in the mangroves was finally shut after flowing for two months: now nothing living moves in a black-and-brown world once teeming with shrimp and crab.

Not far away, there is still black crude on Gio Creek from an April spill, and just across the state line in Akwa Ibom the fishermen curse their oil-blackened nets, doubly useless in a barren sea buffeted by a spill from an offshore Exxon Mobil pipe in May that lasted for weeks.

The oil spews from rusted and aging pipes, unchecked by what analysts say is ineffectual or collusive regulation, and abetted by deficient maintenance and sabotage. In the face of this black tide is an infrequent protest  soldiers guarding an Exxon Mobil site beat women who were demonstrating last month, according to witnesses  but mostly resentful resignation.