Successful invasions of alien species in island ecosystems often have severe ecological and socioeconomic impacts , and mosquitofish meet two important criteria which suggest that a successful invasion would likely result from their introduction into an area : they can survive under a large range of environmental conditions, especially temperature  and salinity , allowing them to successfully establish populations wherever they are introduced, and they are highly mobile , allowing established populations to spread rapidly. Also, mosquitofish have a history of successful, and ecologically disruptive, invasions outside their native range. They often populate the ecosystems they invade at high densities, and since zooplankton constitute the overwhelming majority of their diet, their presence often results in elevated phytoplankton levels, and even algal blooms . They attack native fish in the ecosystems they invade, compete with them for food, and eat their minnows  . Amphibian species, some of which are also important mosquito predators , have been shown to be particularly threatened by mosquitofish introductions   , as moquitofish eat their eggs and tadpoles. There are at least three related Gambusia species endemic to Hispaniola, and it appears that the proponents of this project have completely overlooked these fish both as a potential native species for use in biological mosquito control and also as species that would be potentially impacted by a mosquitofish invasion. Competition and hybridization with invading mosquitofish have threatened multiple rare species of Gambusia endemic to the southwestern United States, and the invasion of mosquitofish almost certainly contributed to the recent extinction of G. amistadensis in Texas  .
This, of course, is not to downplay the reality of the long history of human suffering caused by malaria in Hispaniola, a history that goes back to the first arrival of Europeans on the island in 1492. Malaria likely played a role in the decline and eventual extermination of the Taíno people who were living on the island when the first Europeans arrived, although probably not as significant of a role as smallpox or the cruel policy of genocide and forced assimilation practiced by the European conquerers. Malaria subsequently spread to much of the rest of the Americas, although contemporary Hispaniola is the only island left in the Caribbean where malaria has yet to be eradicated, with much of the effective disease reservoir being localized to the rural lowlands of Haiti . In 2009, evidence for malaria resistance to chloroquine, an important drug for the treatment and prevention of malaria, was first reported on the island , and in 2010, a massive earthquake displaced over a million people, increasing their susceptibility to the disease . Both events make the need for a campaign towards comprehensive malaria eradication even more timely .
The most essential tool for malaria eradication, however, would be the ability to effectively diagnose and treat malaria across the entire island, with the large scale distribution of mosquito netting to prevent transmission of the disease also being of prime importance . Control of mosquito populations would certainly help these efforts, but the effectiveness of fish introductions is more or less limited to eliminating mosquitoes from fishless ponds. Tree holes, coconut shells, discarded tires, and peridomestic containers are also important breeding grounds for mosquitoes in rural tropical areas   , making fish introductions only effective when integrated with environmental management, other biological methods, and possibly even chemical methods . And fortunately, there are countless species of omnivorous freshwater fish around the world which will also consume mosquito larvae when they are available as a food source and which have just as much potential as do mosquitofish for biological mosquito control within their native range       , making mosquitofish introductions completely unnecessary. There is, of course, one thing that all of these tools for successful malaria eradication all have in common: they all require a significant and prolonged engagement with and investment in rural communities across Haiti.
The potentially severe consequences of this attempt at using mosquitofish to control malaria in Haiti and the rather naive assumptions immanent in its rationale make it a rather curious project. The organization behind it is Operation Blessing International (OBI), a non-profit organization with an explicitly Christian mission and an annual revenue in excess of $400,000,000 founded by wealthy televangelist Pat Robertson in 1978. But there is an additional level of irony in that, even assuming that the intentions at all levels of the organization are genuine, OBI is, by engaging in such deliberate ecosystem engineering, effectively disregarding two important convictions that are nearly universal in Christian theology: that the Earth is God’s creation, and that God’s judgment should not be questioned. In the biblical creation narrative, the reason that Adam, the first man, is placed in God’s creation at all is merely “to tend and watch over it” (Gn 2:15), and Adam is never called upon to improve upon it as he sees fit, or to move things around. Adam’s descendants, at various points in the Old Testament, question God’s judgment and will. “Where were you when I laid the foundations of the earth?” (Jb 38:4) is what God says to Job after one such incident. The Book of Ecclesiastes, echoing its persistent theme of human vanity, asks in reference to the work of God “who can make straight what He has made crooked?” (Ec 7:13).
Pat Robertson has been well known for his large investments in mineral extraction interests in the countries where OBI operates, his use of OBI resources for his personal business ventures, and his close ties to right-wing dictators who violently expropriate land from and enforce crippling economic policies on the people they rule . But whatever the organization’s larger plans for Haiti may be, the project to introduce mosquitofish to the country appears to be nothing more than a gimmick: a mythical “silver bullet” born in the heart of the rural U.S. South and about to be used against an exotic foe for once and for all, which when stripped of the reality of its certain ineffectiveness and its potentially severe consequences, is sure to win over the hearts of North American donors. The long-term consequences of this project for Haiti’s freshwater ecosystems are completely irrelevant to the project’s viability anyways, as it is not the people who live in Haiti and depend on its freshwater ecosystems for their livelihoods who control the means in which their collective suffering is exploited as the Christian tradition of charity is commodified. Equally irrelevant are the theological contradictions inherent in the project, as the project is not in any way an act of Christian charity, but a gimmick which is being sold to charitable Christians. Like the introduction of malaria itself to Hispaniola, the brutal extermination of the people who inhabited the island at the time, the clearing of the island’s forests for plantation agriculture, the damming of its rivers, and the reckless extraction of its mineral resources, the introduction of mosquitofish to Haiti amounts to simply another permanent alteration of Hispaniola’s landscape and ecology for short-term private profit, this time in the name of the empire of Pat Robertson.
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* UPDATE April 27,2011:
Operation Blessing International has said they did not import Gambusia Holbrooki Fish Into Haiti, they introduced Gambusia Affinis. In response, the author of this piece states:
The difference between G. holbrooki and G. affinis is minor. They are both known as "mosquitofish" in American English and though they are two separate species, they are often treated as one in the scientific literature because their biology is very similar. Some of literature that I cited, especially those by Australian scientists, actually deal with G. affinis, since that was the species introduced there (G. holbrooki was introduced in Europe, Asia, and Africa).
I'm not sure if I believe their claim that G. affinis already exists in Haiti, though. When I wrote the article, I searched pretty hard for any evidence that either species had been introduced to the island, but found none. If it was already there, why did they have to fly fish in from Mississippi? And why aren't they using native fish? Perhaps I could contact Dr. Abe personally to clarify this.
They claim that they are not going to release G. affinis into open water, which is good. This doesn't mean that G. affinis won't successfully invade freshwater ecosystems though, especially in the event of a flood.
So, although I will certainly edit my article to reflect their claim that it was G. affinis that they introduced, I certainly will not change my analysis. I'm working on drafting an open letter Bill Horan, which I will post on my website. I plan to address the fact that the press release seems to imply that they didn't just introduce a species of fish into Haiti, which they did. It also does not accept that what they are doing will have ecological consequences, which it will.