Causes of marine pollution and how it affects our ocean environment
Marine pollution threatens the health of our coasts and ocean and it comes in many different forms. Marine pollution can mean plastic litter, other litter such as glass bottles and cans, oil and chemical spills or polluted stormwater drains and rivers flowing into the sea.
The effect these have on the marine environment depends on the type of pollution, the size of the pollution and where the pollution occurs. Some marine environments and types of marine life are more sensitive than others to pollution. The pollution may damage individual sea creatures or plants, or it may damage whole communities of different living things.
What you can do
Preventing marine pollution is vital for the well-being of the sea, the marine life it supports and us! Cleaner oceans mean we can continue to enjoy our beaches for swimming, fishing and recreation.
There’s plenty you can do, either on your own or in a group, to make a huge difference.
- Organise a beach clean-up.
- Reduce your rubbish.
- Make sure only rain goes down the drain. Most drains flow straight to the sea … which means we could end up swimming in anything that goes down them!
- Take care of a local stream.
- Find out more about your local beach.
Wouldn’t it be great if we never saw any rubbish on our beaches? Unfortunately, this isn’t always the case. Picking up other people’s rubbish, if it is safe, is an easy way to help reduce pollution on our beaches and in the ocean. Some people pick up beach rubbish in groups – this is called a beach clean-up. Beach clean-ups are doing great things to reduce marine pollution. If you would like to join a beach clean-up group take a look at the Love your coast website to see if any groups already exist.
If there aren’t any groups in your area, you could start your own!
Studies have shown that about 80 percent of marine pollution comes from the land. So, one of the main ways to reduce marine pollution is to get rid of rubbish carefully, wherever we are. If we reduce the amount of rubbish we make on the land it is likely there will be less rubbish in the ocean.
The best place to start is with YOU. You can reduce your rubbish at home and at school by recycling paper, glass, cans and some plastic containers. You could also compost food scraps and find ways to reuse some of your rubbish.
Some organisations are working hard to reduce rubbish too. The Ministry for the Environment is working with New Zealand businesses to find ways to lessen packaging of their products. Some organisations are using science and technology to discover ways to use recycled items in their products. And more and more organisations are reducing their rubbish by recycling their waste.
3. Make sure only rain goes down the stormwater drain! Most drains flow straight to the sea … which means we could end up swimming in anything that goes down them!
One way rubbish from the land makes it into our oceans is through stormwater drains. These drains collect and remove the rainwater from our streets. Unfortunately anything collected by the rainwater as it travels across the road and down the gutters – like cigarette butts, oil from cars and other bits of rubbish – also goes into the stormwater drains. The drains then transport this mix of rainwater and rubbish to our streams and rivers. These streams and rivers flow out to our oceans and this is where the rubbish can end up.
Fortunately there are lots of things we can do to make sure rubbish is not washed down stormwater drains. Important actions are to dispose of your rubbish carefully and reduce your rubbish. If there is less rubbish on the street there is less chance it will be washed down the stormwater drains. Check out the Reduce your rubbish section above to learn more.
Another great idea is to not wash your cars on the road or on driveways, as the suds and waste from the car washing flow straight to the stormwater drain. Wash the car on the lawn or take it to a commercial car wash that collects and treats the car wash water.
A fun way to get the message out about stormwater drains is to do some drain decoration. Drain decoration is where a picture or a sign is placed near a drain to remind people that what goes down the drain goes into streams and then into the ocean. You need to ask your council whether you can do this first.
As most streams and rivers flow into the ocean, taking care of them can help reduce marine pollution. If rubbish ends up in a stream or river it will very likely end up in the ocean. Another type of marine pollution that comes from streams and rivers is soil or sediment pollution. Sediment pollution can happen when soil enters waterways that flow to the sea. It is natural for some sediment to enter the ocean, but when there is a lot of it entering the ocean it becomes a problem. Sediment pollution can be increased by human activities such as earthworks near streams or when plants near streams have been removed.
Taking care of streams and rivers can include picking up rubbish, if it is safe, and/or planting trees near the stream – which is called riparian planting. Plants on the banks of streams help to hold stream and river beds together, making them stronger, and stopping soil from being washed away (eroded).
Getting together with a group to take care of a stream is fun. Your council may help groups taking care of streams by giving you some plants, helping you understand how to take care of a stream and even showing you how to test the stream’s health. To find out if there are any groups taking care of streams and rivers in your area, just contact your council. If there aren’t any groups in your area, you can ask the council to help you set one up!
Your local beach is a great place to start learning about the marine environment. You can see many living things at the beach – not just humans! Your local beach is also a great place for you to make a difference. You can make a difference by picking up rubbish and making sure you take your rubbish home with you.
Humans can be affected by marine pollution. Marine pollution can make us sick if we swim at or eat seafood from a beach with certain types of marine pollution. Our regional councils monitor the popular swimming spots in summer and let us know whether it is safe to swim there or not. They also monitor popular shellfish gathering sites and let us know if it’s safe to eat shellfish from these areas.
To check out the condition of your local beach you can visit your regional council’s website – almost all the regional council’s websites have up to date information on the popular swimming spots. Use this link to select your regional council’s website.
A new tool that can help you learn about and help monitor the coastal ecosystem and its condition is Marine Metre Squared [Marine Metre Squared website]. It was created with funding from the Community Environment Fund and the University of Otago.
You can also ask your family and friends to get involved in reducing marine pollution!
Find out more
For lots of other great ideas on how to take care of your beach and coastline check out the following websites:
This week is New Zealand’s annual national week about the sea, hosted by the NZ Association for Environmental Education (NZAEE website]. It’s about exciting and inspiring all New Zealanders to renew their connections with the sea.
Find out what's on in your area on the NZ Association for Environmental Education seaweek website.