Short answers, pulled from the story.
The Volga Delta covers approximately 49,000 square kilometers today after expanding from roughly 25,000 square kilometers in 1880. This growth occurred as sea levels changed throughout the 20th century.
The Volga Delta sits in Russia's Astrakhan Oblast north-east of Kalmykia and drains into the Caspian Sea about 100 kilometers downstream from the city of Astrakhan. It occupies an arid climate zone characterized by very little rainfall.
The Astrakhan Nature Reserve was set up on the 1st of January 1919 to safeguard the unique ecosystem developing at the river mouth. It stands as one of the earliest examples of such protection in Russia.
BirdLife International designated the delta an Important Bird Area because it supports significant numbers of many waterbird species including pink wading birds known as flamingoes. These birds add color to the otherwise muted landscape of mud and reeds.
The Volga Delta lost approximately 350 square kilometers of wetlands between 1984 and 2001 which equals an average of about 20 square kilometers per year. This loss resulted from natural causes combined with human-induced industrial and agricultural changes.