Especially at risk are semi-natural agro-steppes in Iberia home to great bustards, little bustards, lesser kestrels, and rollers.
Iconic bird species like great bustards are losing their habitats at an alarming pace in Europe, the authors of a new study warn. Within the next century these birds’ last remaining habitats could shrink by as much as half with more and more land being converted to new agricultural uses.
Semi-natural agro-steppes in Iberia are home to populations of great bustards, little bustards, lesser kestrels, rollers and other threatened species. Yet these habitats are undergoing great changes even though they have been designated as Special Protection Areas as part of the EU Natura 2000 network.
Currently, these agro-steppes cover 36,000 hectares in Spain and Portugal and support a third of the world’s population of great bustards, or up to 15,000 individuals, with cereals being cultivated in a low-intensity rotating system.
“Yet these low-yield farmlands are being converted to permanent and irrigated crops, which dramatically changes the open landscapes that provide resources for important bird populations,” explain the scientists, who work at at the University of East Anglia in the United Kingdom and the University of Lisbon in Portugal.
“Traditional olive groves and vineyards are occasionally used for feeding or resting by great bustards, little bustards or sandgrouses, but the modern versions of these and other permanent crops are intensively managed and inadequate for such birds,” they elucidate.
At current rates of conversion, the birds’ habitat will decline by a fifth by mid-century and another in another 60 years. “Declines will be more severe if the demand for products derived from permanent or irrigated crops continues to increase,” the experts note. “For example, with high demand for Mediterranean products such as olive oil and wine, agro-steppes within SPAs may soon be the only areas left to be converted.”
The result of extensive habitat conversion in Iberia will spell trouble for great bustards, a species of bird that inhabits grasslands. Some two-thirds of the bird’s populations now live in Portugal and Spain. “Agro-steppe area losses occurred across all sites surveyed but were 45% lower inside Natura 2000 compared to non-protected areas,” the scientists explain in their study.
“Natura 2000 sites still lost over 35,000 ha of agro-steppe habitat in 10 years, an area that could hold more than 500 great bustards,” they add. “At the current rate of habitat conversion, agro-steppes could be reduced to 50% of the present area during the next century.”
Ineffective enforcement of conservation measures, coupled with low levels of cooperation from farmers, are among the reasons that many endangered species are losing out to economic activities even within protected areas.
“It is crucial to develop new agricultural methods and improve agricultural productivity to feed an increasing human population. This should reduce pressure on the conversion of natural habitats into new agricultural areas,” says Aldina Franco, an author of the study.
“However, at the same time, we also need to allocate large areas of land to less intensive agricultural methods where human activities are compatible with the persistence of wider countryside species and deliver a variety of ecosystem services and resilience. Finding this balance is a challenge for humanity.”