It has been warned that many endangered bird species is predicted to decline by 50% in species by the turn of the century. This primary factors responsible for this decline is the rapid decline is due to the transition from agricultural fields to a more profitable, homogeneous crop cultivation in wine vinyards and olive.
Low intensive agriculture practices across European lands had created a semi-natural aggro steppes ideal for maintaining populations of these endangered bird species such as great bustards, lesser kestrel rollers etc.
These aggro steepes had become special areas of conservation in the early 2000's under the EU natura 2000. Researchers for the University of East Anglia (UEA) and the University of Lisbon investigated the effectiveness of these protected areas of the risk of great bustards population in the Iberian peninsula.
It had been discovered that traditional, less intensive vineyards and olive groves were suitable at maintaining great bustard populations, however, with demands increasing these areas have become more heavily cultivated with permanent crops. If these market pressures are maintained it is estimated that the predicted 50% of endangered species will have gone extinct. Researchers have stated that lack of enforcement and initiatives have led to the demise to the EU Natura 2020 network.
The co-supervisor of this survey, Dr Aldina Frances of UEA had stressed of the importance of development of new agricultural practices and improving the productivity such as improving efficiency of photosynthesis of crops which will be looked in another post. The improvement in efficiency will alleviate the pressures and help prevent high intensive farms.
Great bustard breeding sites are often chosen based on where the mother had been laid and so it is common for many generations of these great bustards to be at the same site and so the transition from aggro steppes to vinyards/ groves.
It was declared that allocating large intensive aggro areas to less intensive management would greatly improve the endangered bird populations where they deliver a variety of ecosystem services and resilience. Leaving large unkept margins which will encourage larger invertebrate composition and diversity where chicks feed exclusively on invertebrates for numerous invertebrates. The survival of these chicks are significantly dependent on their food availability near their nesting site. Improving invertebrate composition within the area will create a larger bottom heavy age structure which is the main way ecologists predict population growth.
A serious concern over these protected sites is that it will create small isolated islands only allowing a carrying capacity for small populations. This will reduce the genetic diversity where the genetic alleles have little diversity between individuals in each island population. Inbreeding will then make it difficult for these individuals to adapt to environmental change and offspring will have reduced chances of survival. Analysis of the genetic diversity of these individuals will be vital and once alleles become too similar within the population, translocation of individuals from a different protected area (island) will have to be introduced for genetic rescue.
