A study published this week in the journal PLoS ONE revealed that, contrary to expectations, bird species have been dying out at increased rates since the mid-20th century, and that most of those extinctions are now taking place on the continents. Researcher Judit Szabo of Charles Darwin University says that historically islands saw the most extinctions as human expansion took place in those areas, but “most of the really susceptible [island] species are long gone.” Conservation efforts are making some impact, but it’s not nearly enough, according to the research team.
What’s the Big Idea?
Agriculture development leads to disruption of fragile ecosystems and habitats and poses the greatest threat to endangered birds right now. Unregulated hunting and the addition of invasive species drove most extinctions in the past. These events, alone or in combination, led the researchers to claim that “humans have directly or indirectly caused most bird extinctions since 1500.” In all that time they were only able to pinpoint one extinction that was caused by a natural catastrophe: A volcanic eruption on an uninhabited Mexican island wiped out an entire bird population in the 1950s.