Here are four reports on Maori adult literacy. Numeracy appears in most of the under the banner of LLN (Literacy, Language and Numeracy). However the last report does give some discussion on numeracy (see page 23).
Report 1

Report 2

Report 3

Report 4

None of the above reports refer to the broader theoretical and research framework of ethnomathematics.

These following papers do.

This discussion by Barton and Fairhall does.

Some research by Glenys Holt which makes the link between maori mathematics education and ethnomathematics. (Just click okay and you will get the document - you do not have to sign in.)

Acquiring the Mathematics Register in Te Reo Maori

Màori and Mathematics: “Nà te mea he pai mò tò roro!” (Because it’s good for your brain!)

The role of language in mathematics (discussion drawn from the maori experience)