"It is morally unforgivable for the Government to have slashed conservation funding, as this Government has done, in the face of the threat that we face.''
Mr Hague said the 1 per cent figure was not plucked from the air and it had political value.
"That's the kind of level of investment that will actually make a meaningful difference in conservation.''
The money would be specifically targeted at species recovery and pest control work, which the party planned to extend.
Legislative change was on the party's cards, and Mr Hague also released the Wildlife (Threatened Species Protection) Amendment Bill today.
The bill would give the Minister of Conservation and DoC greater powers, introduce stiffer penalties for people caught killing native species, and require DoC to create recovery plans for endangered species and ecosystems without them.
Co-leader Metiria Turei said the conservation policy was very dear to the party's heart, and should be just as important to all New Zealanders.
"Conservation policy and conservation work is the backbone of our clean green brand, which is worth some $20 billion to the New Zealand economy,'' she said.
"Every dollar that's invested in conservation, in our environment, is a dollar invested in our economy and in our future, and it pays back.''
Forest and Bird advocate Claire Browning welcomed the party's plan to put in place better protection for threatened native wildlife, but said the funding target still fell far short of what was needed to protect conservation assets.
"Forest and Bird would also want to examine the detail of any legislation, to make sure it is fully effective, and as strong as good overseas models. But overall, this proposal to prioritise and invest in threatened species would improve the outlook for conservation,'' she said.