Moving Birds Around, at Great Peril


The Fatal Strain. On the Trail of Avian Flu and the Coming Pandemic . Sipress, A. 2009 . Viking Press , New York , NY . 386 pp. $27.95 (hardcover). ISBN 978-0-670-02127-7 .
Avian Invasions. The Ecology and Evolution of Exotic Birds . Blackburn, T. M., J. L. Lockwood, and P. Cassey . 2009 . Oxford University Press , Oxford , United Kingdom . 305 pp. $55 (paperback). ISBN 978-0-19-923255-0 .

Globalization and our changing world link these two otherwise different books. As our species moves across geographies with diverse biota in tow (intentionally and unintentionally), we reshape our world in diverse and unexpected ways. The Fatal Strain, an engrossing narrative, examines how we have, only for now, barely dodged a pandemic of avian flu as the poultry trade expands in ways old and new. Avian Invasions, in textbook manner, looks at some of the ecological and genetic patterns associated with our moving bird species around the globe.

The Fatal Strain tells the far more dramatic and compelling story. It reads like a thriller—concerned and even heroic health professionals tracking down suspected cases of poultry-to-people infection, fearing the emergence of human-to-human infections that could quickly change from epidemic to pandemic. These professionals work amid suspicious rural families, incompetent bureaucracies, and defensive governments across Asia. The killer, avian flu, is on the loose, and .… Well, it is not fiction, so we learn just how close we were recently to a devastating pandemic.

All influenza viruses stem from birds. Wild birds (especially waterfowl) are the reservoir of many kinds of influenza, including avian flu (H5N1). In Asia, poultry farming reigns. Life for many Asian peoples, Sipress notes, “would lose its flavor without chickens.” In rice-growing regions, poultry and domestic ducks occur together around paddies and human dwellings. Chicken from such farms are brought to city markets, and live chickens are preferred by buyers. The pervasive tradition of cockfighting also brings humans and poultry in close contact.

In the middle of the last century, an industrial revolution, of sorts, in many Asian countries brought more wealth to rural people, enhancing opportunities to raise and sell more poultry. Commercial farming of poultry began, in which poultry are raised at high densities. The combination of traditional and commercial poultry farms and an increasing international poultry trade have greatly increased the potential for the H5N1 virus to spread and mutate to more virulent forms. And, throughout much of the Old World, it has.

Avian flu was first detected in China in 1996. The first human casualties from avian flu occurred in Hong Kong in 1997. There were no other known outbreaks until 2003 in Vietnam and Indonesia, and then many people died in multiple outbreaks across Asia. The Fatal Strain follows this dangerous trail, visiting villages and the lives of rural families to bring forth a story of death; the difficult politics of the World Health Organization in Asia; the inevitability of more outbreaks; the ever-present risk of an avian flu mutation that will facilitate human-to-human transmission; and the likely and even imminent pandemic we have so far averted by dumb luck. The 1918 Spanish flu that killed nearly 50 million people worldwide and the 2003 SARS (severe acute respiratory syndrome) outbreak are discussed as examples of how such diseases can effectively be contained (the latter) or create worldwide havoc and death (the former). The Fatal Strain, as the title implies, argues effectively that avian flu will inevitably result in an epidemic of historic proportions. The bad guy in this thriller, the avian flu, will eventually prevail over the heroic disease hunters.

Avian flu is also a conservation problem; it has affected wild populations of birds and continues to pose a risk. I have collected tissue samples from shorebirds in Arctic Alaska (2006–present) and in South Korea (2008) for H5N1 avian flu testing as part of a larger effort to conserve migratory birds breeding in Alaska. The U.S. government has allocated millions of dollars for the surveillance of avian influenza among migratory birds. They are concerned that avian flu may spread from birds migrating through Asia to gathering grounds in Arctic Alaska and then southward into the Americas.

I was in South Korea during a massive outbreak of avian flu among poultry and domestic ducks. The army was deployed to cull birds, and at least 7 million birds were destroyed. We donned surgical masks, protective glasses, and gloves when we tested wild birds for H5N1. None of the wild birds we sampled tested positive for avian flu. Likewise, none of the migratory waterfowl, shorebirds, and other birds, many of which migrate through Asia, we and others have tested in Alaska were positive for H5N1. Fatal Strain makes clear just how dramatic and potentially dangerous these outbreaks can be, however. In 2005, 5000 waterfowl, mostly Bar-headed Geese (Anser indicus), were found dead in interior China and the cause of death later was confirmed to be avian flu. This will happen again, yet we do not know where or when. An avian flu pandemic could be devastating for humans and wild animals.

No human lives are lost in Avian Invasions, although many native birds have been displaced and killed by such invasions. In this volume, Blackburn et al. build on an impressive literature on introductions of non-native birds with many graphical comparisons and ecological evaluations.

Islands, particularly tropical islands, are the most frequent sites of non-native species establishment. Most birds are introduced from the northern latitudes. Why a particular species, family, or order succeeds or fails is unclear, and the conditions under which species spread are not generalizable. Human-induced changes in the environment are noted repeatedly as ad hoc reasons for the absence of consistent patterns in colonizations of introduced species. This represents the simultaneously interesting and frustrating aspect of the book and its analyses: there is no recurring combination of stochastic and deterministic factors that can be used to determine whether and how non-native species establish, spread, and interact with other species.

This would be a good book for a graduate seminar, but it cannot stand alone because both history and the context of human introductions of birds scarcely are mentioned throughout. Yet, because introductions of non-native species are driven primarily by human enterprise, students of this subject need more of the context, history, and geography of introductions than Avian Invasions provides. There is but a brief discussion of how European (particularly British) agricultural practices applied in the United States, New Zealand, and Australia facilitated non-native introductions of Eurasian birds that had coevolved with agricultural ecosystems in Europe. A table of the most successful purposeful introductions of non-native birds that included time frames, place of origin, and intent of the introduction would greatly help the reader evaluate and interpret the many analyses in the book. Pairing this book with Long's (1981) detailed history of bird introductions and perhaps Crosby's (1986) seminal treatment of the ecological effects of the homogenization of European ecosystems would make for a rich seminar series.

History and context matter greatly in understanding both of these volumes. The world might be spared a pandemic if the movement of live poultry across borders was greatly curtailed and some environmental disasters spared if we ceased translocating species across borders. But as history and ongoing globalization make clear, we will not cease either.