How the oil spill may be keeping birds alive

Marginal Revolution | Alex Tabarrok | Number of Birds Killed

Number of birds killed by the BP oil spill: at least 2,188 and counting.

Number of birds killed by wind farms: 10,000-40,000 annually.

Number of birds killed by cars: 80 million annually.

Number of birds killed by cats: Hundreds of millions to 1 billion annually.

Don't worry there is some good news.

Number of birds killed by fisheries: tens to hundreds of thousands annually (fortunately for the birds, some of these fisheries are now shut down).

Assume the number of birds killed by oil will more than double to a round 5,000.

Let "tens to hundreds of thousands" be read as "2 * 10^4 to 2*10^5."

Finally, use the last to approximate the number of birds killed by fisheries as 2 * 10^4.5 ≈ 63,000.

We can conclude that if US fishing is down by any more than 5,000/63,000 = 8% as a result of the spill the number of birds killed this year can be expected to go down.