Far be it from me to imply that the birds are the innocent victims of oil spills not be rescued. I understand and am sympathetic to the desire to save the oiled birds, and in my early career I helped organize bird rescue response. However, those who do this work should realize they are doing far less good than they would like. Oiled birds die at a rate several times higher than not-oiled birds. This is the message of the data, not the messenger.

After the 1989 Exxon Valdez oil spill, Exxon petitioned the court for financial credits for the costs of shoreline cleanup and oiled wildlife rescue. The court granted these requests, which reduced Exxon's obligation by more than $1 billion. However, the court apparently did not consider whether cleanup was effective.

To look at the effectiveness of cleaning oiled birds, I analyzed all band recoveries of oiled birds that had been cleaned and released in North America since the Santa Barbara blowout in 1969. Cleaned birds are banded with identifying numbers and an address where to mail the band. I found after analyzing 219 recoveries of banded birds that, at best, very few, about 10 percent, of cleaned birds survive a year.

Every time there is an oil spill, wildlife rehabilitators claim that better rescue, cleaning and treatment techniques result in more birds surviving. So I compared days survived from 1969 to 1989 with data from 1989 to 1996, and with data from spills that occurred in California after 1996. The data show that newer techniques are not significantly more effective.

Cleaning techniques have not changed; the same detergent used in the 1970s is still used today. Even with supposedly better veterinary treatment developed since Exxon Valdez, only a small proportion of oiled birds and wildlife are rehabilitated enough to allow them to survive after release. It has been found that most of the birds become sick from oil swallowed, inhaled or absorbed.

In summary, the mortality of oiled birds is five to 10 times that of non-oiled birds, and a large proportion - 90 percent or more - of oiled birds do not survive after release. It should be noted that it is the policy of some European countries and some U.S. conservation organizations to euthanize oiled birds.

What concerns me is that this truth is largely withheld from the public, which fervently hopes that bird rescue is fixing the oiled bird problem. The reality is, once oil is in the water, there is little that can be done except to assess damages. We Americans are a can-do culture, and a we-can-fix-it attitude is the norm. The BP spill has changed all that: the damages it is causing cannot be fixed. We have to realize that oil spills of the scale of the BP spill can only be prevented. Worse, these large spills must be endured, even when the thought of enduring such an evil is almost impossible to ask.

For the public to believe that cleaning oiled birds means they are being saved is worth millions of dollars in PR to the corporation responsible for a spill. This is why the American Petroleum Institute funds bird rescue organizations, whose work protects the image of the BPs and the Exxon Mobils as being concerned about oiled wildlife.

This article has been corrected since it appeared in print editions.