In 1913, the whole of Southern Dobrudja was incorporated in Romania, but was returned to Bulgaria in 1940, when the area was visited once again by Petrov to examine the colonies of birds that nest there.
În 1913, întreaga Dobroge de Sud a fost anexată de România, revenind la Bulgaria în 1940, când Petrov a vizitat din nou lacul pentru a examina coloniile de păsări care cuibăreau acolo.