H5N1 bird flu "won't be able to be eradicated and it will be here to stay" - that's the view of the Ministry of Primary Industries (MPI) as it prepares to cope with further cases of the strain.

Representatives from MPI and the Department of Conservation (DOC) briefed MPs during a select committee hearing on Thursday.

Deputy director-general biosecurity Stuart Anderson told the committee the disease would ultimately become "endemic" and MPI was focused on reducing its impact on threatened species and the poultry industry, and protecting human health.

There had been no new detections of the disease in other birds but there would be more.

"This is going to be something that is ultimately going to be here and spread and we'll have to learn to manage and live with it," he said.

"We're in the very early days and very early stages of that ... we don't know how all the different New Zealand bird species will react or how they will be impacted and where and how it could spread and the prevalence, and how it may stay in certain parts of the country versus not."

MPI had agreements with the poultry industry and local governments on how to manage H5N1.

"We've reached out to farmers and we're continuing to reach out to poultry farmers one-on-one to offer support with their plans and their preparedness and work alongside them to help them with their plans and anything they need to do on farm," Anderson said.

DOC's deputy director-general biodiversity Catherine Wilson said the department had been planning for "several years" to cope with the disease.

"We've got a big workforce in the regions to be able to draw on, so at the moment we have everything we need," she said.

"We'll keep an eye on that for the foreseeable future ... if there comes a point where it's bigger than we anticipated, then we'll take a look at what we need and ask for more resource," Wilson said.

Anderson said the disease had a high mortality rate, meaning if a poultry farm was infected, over 90 percent of the birds would likely die.

The birds would need to be culled and the farm cleaned and disinfected, he said.