Extent of damage from Gulf of Mexico oil spill still uncertain

Scientists have given a clean bill of health to the Gulf of Mexico one year after the BP oil spill, that raised concerns of permanent ecological damage to the fragile marine ecosystem.

Some blemishes apart the overall picture testifies to nature's resiliency, according to an Associated Press survey of researchers.

More than three dozen scientists rate the Gulf's big picture at 68 on average, using a 1-to-100 scale.  This is only a few points below 71 rating the same researchers gave last summer when asked what grade they would give the ecoystem before the spill. It is also an improvement over the 65 given in October.

However, there is some cause for concern. Scientists point to significant declines in a number of key health indicators such as the state of the sea floor, dolphins and oysters.

Dozens of health experts have in interviews cited the mysterious deaths of hundreds of young dolphins and turtles, crabs with strange stains and dead patches on the sea floor to point out that all may not be well deep down.

Meanwhile, there is no let up in efforts to resume drilling even though some experts say new safeguards put in place to prevent another oil spill do not go far enough.