Actually, Zhang only gave the visitors a brief primer, after all, this is the wolf exhibit, where the emphasis is primarily on wolves; the reasons behind the decline in the elk population in Yellowstone National Park are somewhat more complex.
Indeed, the deer in Yellowstone are not moose but elk. This confusion can be traced back to a historical issue, where someone, during the initial translation, mixed up moose, caribou, and elk, leading to a series of errors in dictionaries including reputable sources like "Ciyuan" and "Zoology Dictionary." Corrections appeared in scientific journals at the end of the 20th century, but even now, many still mistakenly refer to elk as moose.