Need to know

Tuesday - 7/13/2010, 9:21am EDT

If you watch or read the reporting on the BP oil gusher, you will hear Gulf residents talk about the loss of their livelihoods and the long-term damage to the region.

There is no question that much of the fishing industry in Gulf states has been affected. And those businesses that are tied to the fishing industry such as restaurants are losing money, too. Gulf coast tourism business also is down.

These are the short-term damages. With work, they can be documented and a cost attached.

But the long-term impact is not so well known and the research is conflicted, depending on your source. There seems to be a shortage of such information on three of the major oil spills in the last 30 years.

Those three are the 1979 spill off the coast of Mexico, called the Ixtoc One spill; the Exxon Valdez spill in Alaska's Prince Williams Sound in 1989; and the Persian Gulf spill at the end of the Iraq War in 1991.

None is identical to the BP spill. The Ixtoc spill is similar because of its location in Gulf waters and it was an off-shore, oil rig. It was in much shallower water than the 5,000-ft. Deepwater Horizon well.

The long-term effect of the Ixtoc disaster has been far less than many environmentalists predicted at the time. Luis Soto, a Mexican marine biologist, said recently, the consequences "are not as dramatic as we feared." Wes Tennell of the Texas Harte Research Institute, concurred. "It is rather baffling to us all."

The reports from the Persian Gulf spill, second largest to the BP spill, are mixed. A study three years afterwards showed large numbers of fish and aquatic animals were killed quickly in the first year, but not so much impact long-term. One account says the Kuwaiti coastline mostly has recovered naturally, but there is lasting damage in the soil where oil pools sank underground.

The Exxon Valdez has received more attention, partly because the company was required to finance impact studies. A team from the University of North Carolina in 2003 found damage far beyond the 250,000 seabirds, marine mammals and other coastal organisms that were killed immediately. The cold temperatures and geography of the sound have diminished the natural cleansing by wave action, light and bacteria.

The BP Gulf disaster will be studied more than its predecessors. We didn't even know for weeks just how much oil was gushing from the well. Will the long-term effect be more like Ixtoc or Exxon Valdez? Do we need to look again at the other big spills? We need to know more.