Planting Trees can Decrease Wader Populations

A room with a view; many waders require open space in which to breed. Here it is a European Oystercatcher © Andrew Whitelee

We all know the benefits of reforestation. Reversing human land conversion, increasing carbon capture and reinstating habitats can be no bad thing, right? However, there is more to consider here, such as the species that use open spaces, such as ground-nesting wader birds.

Predators use trees as vantage points to survey their domain in search of food CC TheOtherKev via pixabay

The action of planting trees in Iceland is having a negative impact on waders, specifically Charadrii. This area has rarely been forested in the past, and this is only possible now due to climate change. From a recent studyit has been suggested that wader species densities are reduced within forests compared to 700m away. The species affected are the European Golden Plover Pluvialis apricaria, Eurasian Whimbrel Numenius phaeopus, Eurasian Oystercatcher Haematopus ostralegus, Dunlin Calidris alpina and Black-Tailed Godwit Limosa limosa. This is due to the loss and fragmentation of the open habitats which are characteristic of this region. Additionally, rather than their native counterparts, non-native trees are common in forestation attempts, altering biodiversity.

European Golden Plover in breeding habitat © Elis Simpson

These factors may also allow additional predators to live in wader habitats. Regarded as one of the most important areas for breeding waders in Europe, protecting these Iceland habitats is essential.
The study calls for increased bird behaviour and demography tracking to be able to assess the real impacts of the planting. They are also asking that tree-planting schemes avoid areas with high bird density and optimise the size and shape of forest plots to reduce the impact.