ducks: the dreamer is giving up the chance to establish a partner relationship, which causes indignation in some people.
animals: this is usually a positive dream since the dreamer is actively eliminating part of the instinctual essence, but it should be realized that in killing animals we achieve only temporary elimination and these in time rise again, strengthened by the dimension of our attack (see Killing or see individual animals that the dreamer is shooting).
people: the dreamer is not able to control his suppressed aggressive sexual instinct in the subconscious, and therefore the power of instincts is growing and in penetrating into the waking consciousness can even overwhelm the categorical imperative*53 that has thus far prevented the dreamer from carrying out horrific acts.