Wednesday 13th Nov,12:00pm



  • Tanya Blakely
    Boffa Miskell



NZ has just over 50 species of freshwater fish, of which at least 35 are native and 31 are endemic (found only in NZ). What's more, an unusually high proportion are diadromous (where they have freshwater and marine phases in their life cycles). So, it's important that fish can move freely along waterways and to / from the sea. With around 70% of our indigenous fish species ranked as Threatened or At Risk we need to take care when working in waterways.

Freshwater fish are found in a variety of water bodies, many species are small, cryptic, well camouflaged  or nocturnal, and people are often surprised that fish are present in an otherwise benign looking water body. This means that often we come "unstuck", encountering fish when we didn't expect it, accidentally stranding or killing fish during routine maintenance and other works in or near waterways.

Unlike other indigenous fauna, fish are not protected by the Wildlife Act. Freshwater habitats are protected by the Resource Management Act, and DOC and regional councils have specific responsibilities to manage fish passage in our waterways, but freshwater fishes are not afforded the same protection as species such as land snails, bats, and kiwi.

However, section 70 of the Freshwater Fisheries Regulations states person shall...intentionally kill or destroy indigenous fish...and shall not leave the fish upon the bank...

This isn't a commonly understood piece of legislation, but it can have some hefty consequences if things go wrong.

Today, I'll share some case studies where things have gone well and not so well. I'll discuss what Best Practice looks like when working in waterways. When does a specialist need to be involved? How do you know if a waterway has fish in it? Do you need to salvage freshwater fish?

Tanya Blakely
Principal Ecologist, Boffa Miskell


Tanya is a freshwater scientist and ecological consultant with Boffa Miskell. With 15 years of professional experience, she has an excellent understanding of the range of pressures on, and drivers of, aquatic ecosystem health.

Tanya is passionate about freshwater ecology and works closely with a variety of clients, including government agencies and infrastructure contractors. She continues to work with these clients to develop best practice guidelines for works in and around waterways.