A rare bird in Syria is at risk of extinction after Palmyra, one of the country’s most ancient cities, was captured by the Islamic State group earlier this month, BBC reported, citing experts. The bird, called the northern bald ibis, was declared extinct in Syria over 70 years ago until seven of them were found near the city of Palmyra in 2002.

Despite being protected, the bird's numbers in Syria declined to four, and three of them were abandoned last week when their guards fled Palmyra after ISIS seized the city, BBC reported. Officials have offered a reward of $1,000 for information about the whereabouts of a fourth bird, called Zenobia, as it is the only bird that knows the species' migration route to Ethiopia.

“Culture and nature they go hand in hand, and war stops, but nobody can bring back a species from extinction,” Asaad Serhal, head of the Society for the Protection of Nature in Lebanon, told BBC, adding that finding Zenobia is critical because without this bird, other captive birds cannot be released, raising threats of the species’ extinction in Syria.

The northern bald ibis is large, glossy and black, measuring about 30 inches in length, with a wingspan of about 53 inches. According to satellite tagging of 13 Syrian birds in 2006, three adults in the group and a fourth untagged one wintered together from February to July in the highlands of Ethiopia.

ISIS seized Palmyra, which is considered by UNESCO to be “one of the most important cultural centers of the ancient world,” on Wednesday, after days of fighting Syrian army forces. According to U.K.-based Syrian Observatory for Human Rights (SOHR), ISIS now holds over half of Syrian territory after its seizure of Palmyra. The future of the centuries' old ruins in Palmyra is also at stake as the Sunni extremist group has been known to destroy local cultural artifacts that do not conform to its hardline views of Islam.

“There are no forces to stop them [entering the ruins]… But the important thing also is they now control 50% of Syria,” Rami Abdul Rahman, director of SOHR, said, according to the Guardian.

Last week, ISIS also reportedly beheaded at least four people in Palmyra, with some reports saying that the executed men were fighters with the Syrian regime, while other activists in Palmyra said the men were from a Sunni tribe called the Shaitat. Palmyra’s capture came just days after ISIS took the major Iraqi city of Ramadi, handing the Iraqi government its biggest defeat since last summer.

On Monday, however, Iraqi Prime Minister Haider al-Abadi told BBC that Ramadi would be taken back from ISIS “in days” if Iraq received more support from international coalition partners. Al-Abadi’s remarks came after U.S. Defense Secretary Ashton Carter said Sunday that Iraqi military lacked the will to fight ISIS militants.

“[Carter] was very supportive of Iraq and I am sure he was fed with the wrong information,” BBC quoted al-Abadi as saying. “[Iraqi forces] have the will to fight but when they are faced with an onslaught by [ISIS] from nowhere... with armored trucks packed with explosives, the effect of them is like a small nuclear bomb - it gives a very bad effect on our forces.”