User Review - Flag as inappropriate
Full Disclosure: I am reviewing this book based on one excerpt from this book and the negative impact that it has had on the intellectual integrity of the discussion of feral cats and their impact on wildlife. Invasive species (which most certainly includes cats) is an important topic, so I hope Dr. Pimentel treats it with more care than he gave to his estimate of the economic impact of feral cat predation on wild birds. Dr. Pimentel attempts to monetize wild birds by assigning each bird a dollar value of $30. He arrives at this figure by throwing out three other, unrelated dollar values: 40 cents for each bird observed by a bird watcher; $216 for each bird killed by a hunter; and $800 for each bird reared by a specialist for release. He doesn't share the mathematical formula into which he presumably plugs these numbers to arrive at his result of $30, leaving us to speculate that perhaps the number 30 just felt right and was somewhere in between 40 cents and $216. The 40 cent per bird figure, calculated from data in a 1985 USFS recreation survey, is an utterly meaningless statistic. It takes all the money spent on bird related travel and bird related equipment and presumably spreads it over the number of birds estimated to be in the U.S. at any given time. What Dr. Pimentel either doesn't understand or chooses to ignore, is that bird related travel expenditures are highly disproportionately spent on specific bird watching areas and rare birds. For instance the 2004 Red-footed Falcon on Martha's Vineyard prompted hundreds of bird watchers to book flights, cars and hotel rooms, generating tens or hundreds of thousands of dollars in revenue. Averaging these dollars across every House Sparrow, Starling and Rock Pigeon is simply absurd.