In scientific papers we are very strict about citing sources. Not only do we put a list of our references at the end of papers, but we also indicate which reference gave us which fact right there in the text: “junco fledglings have big fuzzy eyebrows (LaBarbera 2012).” This makes fact checking easy.
Scientists writing for the general public don’t usually do this. Depending on the form of a science-for-a-general-audience column, references may all be at the end only, or they may not be there at all. When researchers write about their own research without any citations, saying “My research shows…” and “Many studies have found…” but not actually citing them, it’s up to you to either blindly believe them (don’t do this) or to check their sources yourself. If they do good research, this shouldn’t be hard.