To put it quite simply sadly there is nothing you can do frogs and toads like salmon imprint on the pond they are born in and will come back year on year

Here in the UK toads are in decline so there are Toad Watch volunteers that collect them from roads and inacsesable places to transport them to the nearest pond by bucket

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Thhe only thing you could do is cover the pond with a net with 5mm hexagonal openings so as they cannot get intohe water then catch them and take them to the natural pond by hand but in doing this you stop frogs from laying eggs too.

Shy of euthanizing the toads I dont know what else you can do apart from suggest your neighbour use ear plugs during the mating season, how you do that I dont know ?
Val askes how long have you had the pond how many years you have had toad song and why is it only now the neighbour is complaining (are they new to the area)?

Sadly there are people like them that forget that his or her house was more than probably built where these toads have their natural habitat as such they should either like it or lump it
We have sad rich folk who think it great to buy a house in a country village then when the cock crows at 04:30 am every morning or the church bells ring on Sunday morning they complain it is spoiling their sleep or the manure in the farm next to the village is smelling.:LOL very sad but true

Perhap's you should employ them into catching these toads , it is after all "they that are complaining" not your next door neighbour which wefind very strange dont you ???
If you have a local toad watch as I mentioned we have in the UK , you could get them to help you collect toads as they near your pond

Another suggestion would be to net out all the toad eggs and either spread them on the lawn to dry out or transport the eggs by bucket to the nearest large body of water perhaps you could also contact the ASPCA your equivulent of the RSPCA for help and afvice on this matter as they may know of a toad watch organisation or perhaps you start a group up of well meaning folk to help and relocate the toads as they head for yours and others ponds
I would suggest you take them further away than the three miles perhaps twenty would be better, going off the rate of travel the cane toad does in Australia per day of around three miles daily
Dave
