Decline of bird species belongs in long grass, say scientists

The research, published in the journal Biology Letters, shows that the sex of chicks can be determined by the degree to which land is grazed by sheep and cattle. Any imbalance in the sexes could lead to a reduced bird population.

Led by Dr Darren Evans, lecturer in conservation biology, they worked with academics from the Hutton Institute in Aberdeen and the Universities of Aberdeen and Glasgow, and examined different areas of grazing land to see how it impacts on the breeding meadow pipits Anthus pratensis, the most common upland bird in the UK.

They found that mothers nesting in fields grazed at low intensity produced more male offspring, whereas those nesting in ungrazed fields or those with a high intensity of livestock produced more female offspring.

Dr Evans said: “This latest study highlights the often subtle ways in which birds respond to intensive grazing pressure, but which could have dramatic impacts bird populations.

“Livestock grazing is associated with the widespread decline of various species across the world so it is important this issue is looked at further.”