Teamsters Local 727 has filed an unfair labor practices charge against Brookfield Zoo following the termination of 60 employees deemed non-essential. The union states that workers were layed off without notice or compensation which is in violation of their labor contract. Presently, Brookfield Zoo is closed due to the coronavirus pandemic which prompted the layoffs.
See "Union files claim following zoo layoffs ", David Roeder, Chicago Sun-Times, April 7, 2020