"Before everyone gets excited about Pruitt, remember we're going to get all the same horrific policy under Andrew Wheeler, without any of the comic, attention-drawing personal corruption", Vox environment writer David Roberts tweeted after President Donald Trump announced on Thursday that he had accepted Pruitt's resignation.
Mr Trump confirmed Mr Pruitt's resignation on Twitter, saying he had done "an outstanding job".
Last month, while praising Pruitt's "fantastic job" at the EPA, the president admitted, "I'm not happy about certain things, I'll be honest".
"It is extremely hard for me to cease serving you in any capacity, but also, because of the transformative work that is occurring", Pruitt wrote in his resignation letter to the president. Bernard Sanders, Vermont independent, said in a statement after news of Mr. Pruitt's resignation broke. Lawmakers also expressed concerns about reports that Pruitt used EPA aides to set up meetings about getting his wife a job, which could violate laws that prohibit using a federal position for personal financial gain. At least for the immediate future, Pruitt's deputy, Andrew Wheeler, would take over at EPA as acting administrator.
The decision to cancel the trip because of the shutdown was also a curious one given the fact that Pruitt was encouraging his own employees to report to work as normal. Republicans from Iowa, Senators Joni Ernst and Chuck Grassley, have also spoken harshly against Pruitt's for a proposal to change rules regarding ethanol and renewable fuels.
The Environmental Working Group called Pruitt "unquestionably the worst head of the agency in its 48-year history".
Three poachers are eaten by lions at South African nature reserve
In 2016, the reserve lost three rhinos when poachers got into the park and shot them dead and cut off their ivory horns. Due to its prominence and collection of animals, the park has faced multiple break-ins by poachers in recent years.
Pruitt's general financial stewardship of the EPA has come under examination, and The New York Times reported a number of high-ranking EPA officials were shifted from their posts when they questioned his expenditures.
During congressional testimony in April, Pruitt was unapologetic for the controversies, often blaming his staff for any agency missteps.
He also ordered the installation of a secure telephone cabin in his Washington office at the cost of US$43,000, which critics found excessive. Trump told reporters later that Pruitt had approached him and offered to resign, as opposed to being pushed out.
The departure marked a precipitous fall for Pruitt, who during his roughly 16 months in office took steps to reverse more than a dozen major Obama-era regulations and overhauled key elements of the agency's approach to scientific research.