What kind of person shoots a wild horse?

This young filly was one of the Heber Wild Horse Herd.  She was most likely shot and killed on either Friday April 28, or Saturday April 29, 2017.  This photo was taken on May 4, less than a week later.  Nature's scavengers were quick to find and take advantage of what some demented human or should I say monster, had needlessly done to this innocent creature.  A mentally stable human would never do something like this.  
This shooting is considered animal abuse. So what kind of mindset is behind animal abuse and killings?  From the article "Abusing Animals: Some Psychological Reasons Behind Animal Abuse" by Dr George Simon, PhD

• Serious intentional abusers actually derive satisfaction from hurting animals. From a psychological perspective, the reason is mainly about power. For the most part, animals, especially smaller or domesticated animals, can’t easily defend themselves and are vulnerable in the face of someone who can inflict great pain on them. This makes the abuser feel powerful. Some abusers feel a lack of power in other areas of their lives and try to make up for it by wielding ruthless power over the weak. Others simply enjoy the feeling of dominance so much that they’re always looking for an opportunity to exercise it. Still others have such a feeling of superiority and entitlement that they view the animal’s only purpose as being to serve their needs. Such is often the case when animals are used for fighting contests (e.g., dog fights, cock fights, etc.) as a way to make money for and gain notoriety for the owners and handlers.

Animal abuse is a serious and fairly widespread problem. It is seen across many cultures, age groups, and sexes. If you know someone who is engaged in the serious, intentional abuse of an animal, the chances are that they need psychological help. What’s more, the reason many animals continue to endure abuse is because good people don’t take action. 

https://askthepsych.com/atp/2009/06/05/psychological-reasons-behind-animal-abuse/