My thoughts are this: Humans no longer have a natural habitat. Therefore, natural habitat would be for animals and/or plants. Without more context, it's impossible to know whether you are talking about the endangered havest field mouse or the rare lady slipper.
In the European Union, a “natural habitat” is understood as a “ terrestrial or aquatic area distinguished by geographic, abiotic and biotic features, whether entirely natural or semi-natural”. This definition has been established by a Council Directive (92/43/EEC). Part of my job has to do with management plans for the protection of "natural habit