Rid of Salamanders in pond

Question
QUESTION: I read your answer to getting rid of salamanders by adding fish to the pond.  The problem I have is we are irrigating with gray water-disposal and the system is getting clogged up because of the number of salamanders in the pond. We are looking for something we can introduce into the pond to rid of the salamanders without effecting wildlife or the hay that is being irrigated. An insecticide that will kill them would be great.  Thanks for your help.

Zeke

ANSWER: Any insecticide would not only kill salamanders but adversely effect the vegetation.
And I am personally against killing any living creature. But you can try to prevent it from coming into the pond. By eliminating the moisture since their body requires constantly to be wet.
If moisture is not present they migrate.

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QUESTION: I understand your concern in killing any living creature but this is out of control.  I can't drain the pond since it is constantly being filled with sewer water from the city so I have to find something to control this creature that is causing great damage to equipment and crop.  We are unable to maintain a steady flow of water to irrigate our crop.  Let me know if you have any other idea.  Thanks

Zeke

Answer
Lets think of options
1)The introduction of predators but they would be posing same problem as salamandars over period of time.
2)Decrease of pH that could effect the salamandars make water acidic but could affect vegetation.
3)Introduce pesticide but would render the plot in effective for cultivation for sometime.