The Islamic State's cruelty has (and is) costing the lives of countless people, while still others have been enslaved and trafficked. The group's barbarity has also manifested itself in the demolition of priceless historic heritage sites, with the fate of Palmyra's ruins the latest archeological artifacts now hanging in the balance.

But a new report from the BBC suggests endangered wildlife can now be added to the long list of ISIS victims: A rare bird called the northern bald ibis.

The bird was thought to be extinct in Syria, but in 2002 seven were found near Palmyra. Four had survived, but three were abandoned during ISIS' onslaught on Palmyra last week when the guards protecting them fled.

Officials are offering a $1000 reward for information on the whereabouts of the fourth bird – named Zenobia – as it is the only bald ibis that knows the migratory route to Ethiopia and without it the other birds cannot navigate.

Once common across Europe, the Mideast and Africa, the only surviving bald ibis populations were found in Syria and Morocco.