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Information on the long-term effects of the Exxon Valdez oil spill may be found on the web sites www.evostc.state.ak.us/facts, www.valdezscience.com, and http://response.restoration.noaa.gov/spotlight/spotlight.html.
An overview article in Science on the long-term effects is: Charles H. Peterson et al. (2003): Long-term ecosystem response to the Exxon Valdez oil spill. Science 302: 2082-2086. May be downloaded here.
P. 192 bottom right: (COMMENT)
"For the sea otters, `it is clear that recovery is under way´". Comment: This is no longer so clear. According to the paper by Peterson et al. referred to above, the growth rates of sea otter populations during the recovery phase has been smaller than normal. Sea otters born after the oil spill have probably higher mortality than those born earlier. The otters are chronically exposed to oil hydrocarbons via their food, such as mussels, apparently with adverse consequences to their health.
P. 193 left: FLAW
"Pacific herring stocks . . " Flaw: Concerning the effects on herrings, Lomborg´s text is a gross understatement. The effects on herrings were reported in 1997 and were thus potentially avialable to Lomborg. They are summarized on www.afsc.noaa.gov/abl/OilSpill/herring.htm. First, it turned out that weathered oil caused deformation of herring eggs at extremely low concentrations, down to 9 ppb. Such effects existed for some years, but were no longer detectable after 6 years. Second, in laboratory tests, herring were negatively impacted by exposure to oil, principally by suppression of the immune system and increased expression of disease. This means that the temporary collapse of the stocks could be directly related to the effects of oil remains, and not just to an indirect, hypothetical effect as Lomborg suggests.
P. 193 left: FLAW
"Several other species . . but the general impression is that not much damage has been done." Flaw: This is hardly the general impression. The evostc web site that Lomborg has studied, lists the effects on 4 species of mammals, 11 species of birds, 6 species of fish, plus various other organisms, in total 25 types of organisms. In 1998, i.e. in the tenth year after the spill, status was as follows: Fully recovered: 6, on the way to recovery: 6, maybe slowly recovering: 2, not recovering: 6, unknown trend: 5. Although the case for harbor seals, which have not recovered, is equivocal, there is still considerable evidence of long-term impacts for many other species. Considering that Lomborg has seen this information, his presentation seems deliberately biased. In 2001, there was still remained at least 55 tons of oil buried under the surface, and certain organisms, such as sea otters and harlequin ducks, still show signs of being exposed to oil hydrocarbons (see the paper by Peterson et al.). Certain other birds that are in the area only during winter have also been permanently affected. These are not included in the evostc web site.
P. 193 right: (COMMENT)
"John Wiens of Colorado State University says that . . ". Comment: In his studies on the effects on seabirds, John Wiens was supported by funding from Exxon, and the reports on the valdezscience web site seem biased in the direction of downplaying the effects. Nevertheless, this web site states that out of 23 species of seabirds, 12 were not negatively affected, 7 were affected, but had recovered in 1998, and 5 had not yet recovered in 1998. So the claim from 1996 that there were "few persistent or devastating long-term effects on seabirds" does not adequately cover the evidence presented by Wiens after 1998.
P. 194 top left: (COMMENT)
" . . it was roughly the equivalent of one day of plate glass deaths to birds in the US . . ". Comment: This comparison is rather irrelevant. Small passerine birds like warblers and tits produce many more young and have much higher population turnover rates than seabirds. The latter typically produce only few youngs per year, and their populations take much longer to recover than those of small songbirds.
P. 194 left: (REMARK)
". . could we not have put the $2.1 billion to better use?". Remark: Yes, we could. It is true that the cleanup activities had long-lasting negative effects on the intertidal communities. A better use of such money would be to do more to prevent small and large oil spills in the future. Prevention is better than cure.