Ersy was born and raised in New Orleans. She currently lives, and works out of a studio, in her childhood home – a 180-year old house on Esplanade Avenue in the Vieux Carré. Ersy received a Bachelor of Fine Arts from the California Institute of Arts and studied as well at Bard College, The Cooper Union for the Advancement of Science and Art and Tulane University. She apprenticed with both Enrique Alférez and William Ludwig, two prominent New Orleans sculptors. As an educator she taught sculpture classes including bronze casting at Cooper Union for nearly two decades. In 2000, she returned home and joined the Visual Arts Faculty at the New Orleans Center for Creative Arts. As part of the Louisiana Percent for Art Program, she received and executed a commission for the New Orleans Museum of Art entrance gate in collaboration with artist George Dureau. Ersy received a Surdna Arts Teachers Fellowship in 2005 to work with Modern Art Foundry in New York. In 2008, the Ogden Museum of Southern Art acquired her sculptural installation, “Homage to the Society of St. Anne Parade,” now part of its permanent collection.