Idaho Fish and Game Commissioner Blake Fischer poses with "a whole family of baboons" he says he shot on a recent hunting trip in Africa.
Fischer and his wife shot at least 14 animals in Namibia, according to the Idaho Statesman.
The animals that the couple killed include a giraffe, leopard, impala, sable antelope, waterbuck, kudu, warthog, gemsbok (oryx) and eland.
In the photo, Fischer can be seen smiling with four dead baboons set in front of him.
Fischer was criticized by former commissioners for sending the photos to them and others in a September 17 email. Anyways, my wife and I went to Namibia for a week. first she wanted to watch me and "get a feel" of Africa.so I shot a whole family of baboons.
One of the recipients of Fischer's note, former commissioner Fred Trevey, responded on October 5, saying the email "dismays and disappoints me".
Former commission member Fred Trevey also called on Fischer to resign.
Mr Stonebraker said: "They killed a whole family, including small baboons, and I think that's revolting".
"My reaction to the photo and accompanying text of you smiling and holding a "family" of primates you killed, dismays and disappoints me", Trevey said, according to KBOI.
A former commission member, Keith Stonebraker, commented on the situation saying he doesn't approve of Blake's actions, but would like an apology.
Please consider this letter as a statement of my resignation from the Idaho Fish & Game Commission.
The commission Fischer serves on makes policy decisions concerning Idaho's wildlife, and it often manages game populations through hunting and fishing regulations. "I didn't do anything immoral", he added.
"Slaughtering a family of baboons, including a baby baboon, and boasting of his conquest with photos is morally reprehensible", Kitty Block, acting president and CEO of the Humane Society of the United States (HSUS) and president and CEO of Humane Society International (HSI), told The Dodo. Alder is the executive director of the pro-hunting group Idaho for Wildlife. You just don't do that.
Fischer, who told the Statesman he received a call from a fellow commissioner expressing concerns about the photo, said he apologized for sending the pictures, but defended the hunt. Those regulations are meant to require ethical behavior in the pursuit of wildlife.
Meanwhile, Idaho hunting policies, such as that of wolves and grizzly bears, have often been challenged in the federal courts.
Mr Fischer was re-appointed earlier in the year, but is still seeking Senate confirmation before a new term can become official.
Fish and game commissioners are appointed by the governor and confirmed by the state Senate, the department's website states.