As many as 33 Great Bustards, originally from Spain, are to be released in Wiltshire later this year, in a significant expansion to a reintroduction scheme that had previously only used Russian bustards.

The great bustard is the world’s heaviest flying bird, with adult males often growing to over a metre tall. Extinct in Britain since 1832, the Great Bustard Group (GBG) has been attempting to reintroduce the species into Southern England since the early 2000s.

Initially, they were using great bustards from the Saratov region of Russia, who were believed to be the closet genetic relative to the original British birds. However, a recent study by Dr. Paul O’Donoghue of the University of Chester, using genetic material extracted from stuffed British specimens, has suggested that in fact Spanish great bustards are a closer match.

This came as welcome news to the Great Bustard Group, whose previous attempts to introduce the birds had been fraught with difficulty. The UK government only allowed the group to use eggs from destroyed or abandoned nests. This, combined with the logistical difficulties of transporting the birds from Russia, resulted in very few being successfully released in this country. Furthermore, those that were had a tendency to try and migrate towards the south west, with only a handful surviving.

The great bustard population in Spain is the largest in the world, amounting to over 30,000 birds. With permission from both the Spanish and UK governments, the great bustard group was able to collect 56 eggs from the Castilla la Mancha region of Spain.

These eggs were then imported to the UK, and the surviving chicks were reared by a great bustard group and RSPB team in Wiltshire. Staff used a bill puppet to feed the chicks, and wore dehumanization suits to guard against the young birds becoming imprinted on them.

The project has now entered a ‘soft release’ phase, in which the birds are gradually allowed to find their freedom. The first birds are expected to be released at two secret locations in Wiltshire later this year. The group hopes this reintroduction attempt will be more successful, as, unlike their Russian counterparts, Spanish great bustards do not migrate.

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