Our Use of the Sea and Our Impact on It

We are also aware that the quality of our water affects our quality of life -  our enjoyment as an island nation is influenced by the health and viability of our waterways and coastal waters. The sea and its resources are also important economically and culturally. Our seafood industry employs over 8,000 people and makes up around 4% of our overseas exports. For Maori, kai moana and the spiritual and historical connection with the sea is extremely important. Marine tourism is one of the fastest growing sectors in the New Zealand economy.  Mineral, oil and gas exploration and extraction, biotechnology and transport are also other important uses of marine resources.

All of these uses are having effects on marine life. Here are some examples of the impacts that our activities are having on marine ecosystems:

• Around 600,000 tonnes of seafood is caught via commercial fishing activities each year. An unknown amount is also caught be recreational fishers.
• These fishing activities have reduced stocks of around 40 species to a population level that is a fraction of their original levels.
• Many fishing activities kill non-targeted species (particularly trawling)  and this “by-catch” has become a major threat to some species such as New Zealand Sea-lions, Hector’s Dolphins and Royal Albatross.
• Sedimentation (from de-forested and urban catchments) and nutrient enrichment (from farming activities and sewage disposal) in tidal and near-shore environments has substantially compromised many New Zealand coastal ecosystems.
• Heavy metal chemicals (such as zinc, lead and copper) which are washed into the coastal marine ecosystem have accumulated in the food chain and this has reduced reproduction and increased mortality rates for many marine organisms.
• In excess of 140 invasive exotic species of animals and plants have been introduced to our waters.