The south entrance to Brookfield Zoo Chicago is pictured on Saturday, April 18, 2026. Credit: Todd Bannor

More than 200 employees at Brookfield Zoo Chicago who are members of the Teamsters Local 727 union voted Tuesday night to authorize a labor strike beginning Friday, May 1, when the existing collective bargaining agreement is set to end at 11:59 a.m.

The vote occurred after members of the union — which represents workers in the zoo’s animal care, custodial, grounds and police departments — agreed to reject the zoo’s last, best and final offer, given Monday, April 27.

The zoo said some animal encounters and programming may be adjusted or postponed in the event of a strike but that it plans to remain open to the public.

Press releases from both the zoo and the union say workers were seeking increases to wages and guarantees of staffing levels. The zoo said its offer included a 14.5% increase to wages over four years and new bonus compensation opportunities tied to the zoo’s annual performance. Teamsters said the zoo offered increases of less than 3.7% on average over the four-year span of the proposed agreement without long-term staffing guarantees.

“There were three main issues that we started off wanting to be addressed,” said Sean McGough, a business agent at Teamsters Local 727. “Almost every department in the zoo had reported understaffing and, in some cases, safety implications with the short staffing. Wages and subcontracting” were the other two issues, though he said the zoo has made concessions in some areas.

“Throughout bargaining, the union was pointing out that there were health insurance issues, too. The zoo wasn’t contributing enough to the employees’ health care costs,” McGough said. “There was no proposed health care plan that the zoo had in place to replace their current, existing health insurance.”

Kelsey Mauro, the zoo’s associate vice president of communications and marketing, said in an email that zoo representatives were not available to speak Wednesday afternoon.

Credit: Javier Govea

McGough said zoo representatives made mention of providing health insurance but did not provide any details to the bargaining team.

Representatives from Teamsters Local 727 and Brookfield Zoo Chicago are set to meet for continued bargaining Friday morning until the contract expires. It will fall to union leadership and the bargaining committee to decide then whether to proceed with a strike, McGough said.

“It’s unlikely that there will be a strike at 12:01 on Friday,” he said.

The union said in its press release that a full day of bargaining was scheduled for Monday, April 27, and a half day on Wednesday, April 29, before zoo representatives “abruptly ended bargaining early” on Monday.

The current agreement has been in place since April 1, 2022, McGough said. It was set to expire April 1 and was extended another month to allow for continued negotiations.

In the course of bargaining, the union said the Chicago Zoological Society, which operates Brookfield Zoo Chicago, committed “numerous” unfair labor practices, which McGough named as the cause of the strike.

“Throughout the course of bargaining, the union had filed 10 unfair labor practice charges with the NLRB [National Labor Relations Board],” McGough said. “Direct dealing, refusal to bargain, failure to provide information, bad faith bargaining, unilateral changes, retaliation and intimidation. These are all wrapped up over the course of the last couple of months during negotiations.”

The zoo purports its employees’ wages fall into the top 25% among accredited institutions by the Association of Zoos and Aquariums. It said the requested wage increases would cost it about $16 million over the life of the four-year contract with no clear funding source for the additional expenses.

In the zoo’s statement, President and CEO Michael Adkesson called the strike “unnecessary and avoidable.”

“We deeply value every member of our team and the important work they do each day,” he said. “Our responsibility is not only to today’s workforce, but to the future of this institution.”

Stella Brown is a 2023 graduate from Northwestern University, where she was the editor-in-chief of campus magazine North by Northwestern. Stella previously interned at The Texas Tribune, where she covered...