3rd pic has 1 Anredera plant arrowed - a more obvious plant is closer, in centre right of the pic.
A very invasive vine, spreading by aerial tubers that drop off the vines very easily, from where they get spread in waterways and by people dumping garden waste. Most plants of it in Whanganui are below roadways (people's weed dumps) or on riverbanks.
April is always the easiest month to spot Madeira vine in the landscape.
On poplar log above the stream. Paul Gibson, author of https://www.nzherald.co.nz/whanganui-chronicle/news/whanganui-rivers-rare-bird-nankeen-night-heron-captured-in-paul-gibsons-new-book/4YAPMQKBCBEJTIYZSDQ4X3Z4IM/ says this bird would be 18 months old.