The Dictionary of the Spanish Language considers that the words «protectionism» and «protectionist» petenecen exclusively to the domain of the Economy.
In this sense, the noun «protectionism» serves to call up, on the one hand, that economic policy that hinders the entry of foreign products that compete with the nationals and, on the other hand, the economic doctrine that supports such a policy.
Therefore, «protectionist» is everything relating or belonging to the «protectionism» (either as policy or as a doctrine) and is also the word used to call the supporters of both things.
Obviously, the word does not contemplate the possibility of apply it to other «protections» that are not these of which we speak, including in particular the protection of animals.
Those who are devoted to this last activity does not have a unique name: is generally called «protectors of animals», both for the activity carried out as belonging to groups or associations that are called «animal protectors».
To refer to these people with the name «protectionist» is, therefore, an obvious error that should be corrected and, to the extent possible, avoided, in order to use for each situation, each subject and each action is the name most suitable and specific as possible.