United Future leader Peter Dunne says there is no conflict between his role as Associate Conservation Minister and being an opponent of the use of 1080 poison.
The conservation portfolio is one of three Mr Dunne was awarded under his party's confidence and supply deal with the National Party.
One of the country's top scientists, Sir Paul Callaghan, says Mr Dunne is an outspoken opponent of 1080, which he says is essential to keep pests like stoats and weasels under control.
Sir Paul says he is astonished National would approve Mr Dunne for the role of associate minister and the decision sends a mixed message about the Government's commitment to conservation.
Mr Dunne says he would like to see 1080 banned altogether but only when there are effective alternatives, for example better trapping methods.
He has also been a long time advocate of the hunting and fishing lobby.
Mr Dunne says his views pose no conflict to his ministerial role.
He says his portfolio priorities will be establishing a Big Game Council, banning helihunting on conservation land and ensuring public access to lakes and rivers, as laid out in his agreement with National.