Friendly fences for the great bustard

Although agriculture is essencial to maintain the population of steppe birds, some agricultural practices used nowadays, like livestock fences, can have a negative impact on species conservation. Under this project, winner of the "2013 International Conservation Grant of The Conservation Division of the Forestry Bureau,Taiwan", LPN intends to develop actions for the conservation of the great bustard’s habitat, aiming to minimize collisions with fences. Field activities will involve volunteers, thus promoting environmental awareness.

Project contextualization and justification

The Castro Verde region (locally known as Campo Branco) is a rural area in the Alentejo region (South of Portugal), in a semiarid and subhumid area, severely threatened by soil erosion and desertification, where the economy depends on agriculture, mining and other services. This area, a pseudo-steppe ecosystem (or cereal steppe), is considered a valuable natural area, recognized by the Birlife International as IBA (Important Bird Area) and classified by the European Commission of the European Union as a Special Protection Area (SPA) for birds under the scope of Natura 2000 (European Network of Natural Areas).

The main habitat of the Castro Verde SPA is the cereal steppe or pseudo-steppe that is the result of a spatial and temporal habitat composition, with large cereal cultures in a rotation system that includes fallowing (used for pasture), crops (wheat, oats and barley), plowed and stubble.

The Castro Verde SPA is considered the most important area of steppe habitat in Portugal due to its high relevance for the breeding of steppe birds, some of which globally threatened by extinction, such as the great bustard (Otis tarda).

This SPA has been an area of occurrence of these species, but, in the beginning of the 1990s, this agricultural habitat started to undergo some changes in agriculture, causing a high habitat fragmentation, with the disappearance of fallowing lands, an increase in livestock density, afforestation of agricultural areas, increase in irrigated crops or conversion of arable crops into vineyards or olive groves. This land management change could represent the local extinction of these birds. To avoid these threats, LPN bought six properties (with the contribution of the European Program LIFE) for the implementation of an agricultural management compatible with the conservation of birds and developing several conservation projects in this area. Some of the endangered birds’ populations currently show growth trends, reversing the previous decline.

  
The main goal of LPN in Castro Verde is to achieve the conservation of the threatened pseudo-steppe ecosystem through an integrated approach to sustainable development, which guarantees the protection of steppe birds. This approach includes direct actions in biodiversity management, soil protection and formation, water management to increase the resilience in drought situations, development of sustainable agricultural practices, scientific research, and environmental awareness. 

The great bustard and the negative impact of fences 

In the last years, there has been a significant increase in the number and density of fences due to changes in agricultural management (that is, less labor due to rural exodus). In spite the problems raised by fences, agriculture is essential to maintain the great bustard habitat; crops and fallowing lands for pasture are important habitats for the breeding and feeding of the great bustard. 

Fences are an important threat for these birds, due to habitat fragmentation and risk of collision. Because great bustards are mainly terrestrial birds, especially during mating parades, fences can lead to the abandonment of parade and nesting sites that would be high quality habitats. Additionally, collision with some types of fences may fatally injure individuals. The presence of these obstacles may also contribute to increase the juvenile predation. Since 2009, at least 23 great bustards died due to collisions with barbed wired fences in the Castro Verde SPA.

The project Steppe Life, carried out by LPN between 2009 and 2012, developed a methodology to minimize the bird collision with wired fences: black and white PVC plates over the top of the barbed wired have been used as a signaling means to increase the visibility of the fence.

The project “Friendly fences for the great bustard” aims to signal fences, especially in important areas for the great bustard. Fence signaling will be implemented with the support of volunteers. This way, conservation awareness will also be promoted.

Project goals

The main project goals are:

• Ensure the maintenance of a favorable state of conservation of the steppe habitat in the Castro Verde region;
• Minimize the negative impact of fences in the great bustard (collision);
• Raise awareness of the negative impacts of fences for the great bustard.

Specific goals of the project are

• Signal about 7 km of fences to protect great bustard’s mating parade;
• Encourage environmental volunteering, with the promotion of three activities to signal fences.