Why Multi Kill rodent traps are important

Often rodents with the help of humans find themselves in a habitat where there is no natural defence or expectation of rodents in the enviroment and humans who control them have left. And in doing so when the rodents arrive nature often takes a strange turn. 
Mice have been shown to eat nesting birds and their young. They do not know how to defend themselves. 
Poison to control these rodents is clearly not the solution because of the contamination of the poison to the surrounding area and the unethical way the poison will kill. And often it is in effective. 

Multi kills rodent traps are clearly the answer.