People tend to think that threatened species are not able to adopt to changes in their environment. Apparently, Great Bustard is an exception to this. Historically, the species has successfully increased its range and was able to colonise even the British Islands. It was able to coexist with low intensity farming for many centuries. However, it has started to decline rapidly during the 20th century.

Habitat loss

Although the Great Bustard readily occupies certain agricultural crops, the loss and deterioration of its original habitats due to fragmentation by afforestation, irrigation schemes or infrastructure (e.g. roads, settlements) development present a major threat to the species.

Low breeding success due to agricultural works

Although certain crops, especially alfalfa, attract Great Bustard with more favourable feeding and microclimatic conditions than its natural habitat can provide, the breeding success of the species is lower in this habitats because a large proportion of the nests is lost during agricultural works such as cultivation of the land, mowing of alfalfa or grasslands or harvesting cereals. (Occasionally, chicks and females can be also killed during these works because they usually try to escape threats by squatting flat on the ground). Disturbance during grazing of grasslands, spraying of pesticides, applying fertilisers to arable crops or even recreational activities including birdwatching can also lead to nest failures.

Increased adult mortality due to collision with powerlines

A major cause of adult mortality which seems to affect males more than females. (Collision with fences also appears to be an important mortality factor in some part of the range such as Spain and can increase also elsewhere if grazing regimes change). The impact of the additional adult mortality is especially sever because Great Bustard males reach their maturity at the age of 5-6 years old, while females at 2-4 years old. Hence, population growth rate is more sensitive to changes in adult mortality than changes in fertility.

Predation

In addition to agricultural works, artificially high predator pressure (mainly by red foxes) reduces also the survival of eggs and chicks. This is a relatively new phenomena, which relates to recent changes in farming and game management. In Germany, also invasive introduced species also present an increasing threat.

At the breeding grounds

The aim of Great Bustard conservation at the breeding grounds is to prevent further habitat loss and fragmentation, improve breeding success and reduce adult mortality. To secure this, all significant breeding areas, i.e. which qualify as an Important Bird Area, received some form of legal protection in the MoU area by now. In Austria, Germany, Hungary and Slovakia, farmers receive financial support to adopt their farming to the species' requirements. Recently, significant sums were invested into the removal of the most dangerous powerlines and marking others within the breeding ranges of Great Bustard sub-populations.

At the wintering grounds

In the vicinity of the breeding grounds, oilseed rape and alfalfa are sown every year to avoid birds roaming in search of suitable wintering grounds because this is increasing the risk of collision with powerlines, hence adult mortality. Disturbance (e.g. hunting) at the wintering places shall be regulated to avoid forcing the birds leaving this precious resources. In order to avoid starvation or desertion of the area, snow needs to be cleared from the fields when food becomes inaccessible. Nowadays, Great Bustards only leave their usual wintering places under special circumstances. If the species turns up somewhere where it does not occur every winter, it is very important to notify the competent conservation authorities about the presence of the birds and ensure that they are not disturbed. To this end, it is worth asking the collaboration of local hunters and farmers.