Independent candidate Rob Priestly called Mr Birrell on Sunday morning to concede with the Nationals ahead by more than 7000 votes with 85,000 votes counted.
The 4.7 per cent margin is a fraction of that enjoyed by Damian Drum, who retired with a margin of 20 per cent.
“I feel tired, relieved and very humble and honoured,” Mr Birrell said on Sunday.
“It was a tough campaign against some really high-quality candidates.
“Rob has been a friend for a long time and will remain so. I only met Steve Brooks at the start of this election campaign and I have a real respect for him.”
Mr Birrell congratulated every candidate in Nicholls.
“As only we know, it is a very hard thing to put yourself out there,” he said.
Mr Birrell said the issues confronting Nicholls, especially water, would be his priorities from day one.
“I need to pull the community together, those who supported me and those who didn’t,’’ he said.
“This electorate needs to come together to work to get the outcomes from the Federal Parliament that we need.”
Labor’s water minister-in-waiting Terri Butler was a casualty at the election, one of two lower house Queensland seats to fall to the Greens.
Ms Butler had met with members of the Goulburn Murray Irrigation District water leadership group during the last sitting week of Parliament, giving hope that the ALP would listen to concerns about the recovery of 450 gigalitres of upwater for South Australia.
A new minister will have to be found and co-chair of the leadership group David McKenzie is hopeful it will be an opportunity for a fresh look at water policy.
“I’m hopeful the region will be able to meet the new minister really quickly and bring them up to speed with the reality on the ground and the way forward,” he said.
There is the prospect of Tony Burke, who has publicly supported the use of damaging water buybacks, again taking on the portfolio.
The senior Labor figure has been manager of opposition business and spokesperson for industrial relations and the arts.
“It is imperative that whoever Labor chooses as its water minister understands what some of the proposed policies would do to this region,” Mr Birrell said.
“Tony Burke said a number of years ago in Deniliquin that he would listen to basin communities and understand their concerns. He needs to be true to those comments because that wasn’t the experience when Labor was in government last.”
Mr Priestly said he gave the election his best shot.
“It is the first time, maybe ever, but at least in living memory that this seat has attracted national attention and we have been a part of the national political conversation, that is terrific,” he said.
“I think there will be a view amongst the Coalition that this is a seat that needs to be thought about and attended to or there will be trouble ahead.”