On another forum I'm on, someone claimed that it's been "semi-confirmed" that Doug Jones basically made up Kelpians being a prey species. The whole little monologue about food webs in the first episode (which always seemed a bit goofy to me) was essentially made up by him extemporaneously, and Bryan Fuller decided to work it into the show.
This would help resolve something strange regarding the last few episodes - why Lorca, who came from the Mirror Universe, was okay with having what he would consider a food animal as his XO. When the two characters were originally conceived, Lorca wasn't intended to be from the MU, and Saru wasn't intended to be a prey species. Potentially the showrunners came up with the idea of Kelpian being a popular food item in the MU even later in the process.
This would help resolve something strange regarding the last few episodes - why Lorca, who came from the Mirror Universe, was okay with having what he would consider a food animal as his XO. When the two characters were originally conceived, Lorca wasn't intended to be from the MU, and Saru wasn't intended to be a prey species. Potentially the showrunners came up with the idea of Kelpian being a popular food item in the MU even later in the process.