Threats to Scotland's marine and coastal environment

Scotland’s seas and our iconic marine wildlife are under threat. It is important to identify and take steps to reduce the impact of these pressures.

Health of Scotland’s marine environment

Whilst there’s been progress with protecting Scotland’s seas, and our iconic marine wildlife, it is still under threat. Some species continue to be at risk of extinction at a global scale, including much loved seabirds such as the Atlantic puffin (Fratercula arctica) and the black-legged kittiwake (Rissa tridactyla).

The most recent assessment of the state of Scotland’s seas, which pulls together scientific data, evidence and knowledge, was set out in Scotland's Marine Atlas. This assessment considers the extent to which our seas are clean and safe from hazardous substances, biologically diverse and in good quality. The Atlas also provides an assessment of how productive Scotland’s seas are. Productivity is about the benefits we get from our seas and the natural resources they provide, such as food, renewable energy or leisure opportunities.

Threats

A recent global assessment on the state of biodiversity, undertaken by the International Platform on Biodiversity and Ecosystem Services (IPBES) IPBES Global Assessment, brings into sharp focus the threats that still need to be tackled - climate change, invasive non-native species, changes in the use of the seas, exploitation of our natural resources and pollution. Some of these threats can be seen at a local level and others build up cumulatively to affect our habitats and wildlife at regional, national or global scale.

Climate change

The over-riding threat to our marine environment is the risk posed by climate change. The Intergovernmental Panel on Climate Change (IPCC) reports that global warming is likely to reach 1.5°C between 2030 and 2052 if it continues to increase at the current rate. As 90% of the world’s global warming has been absorbed by the oceans, it is unsurprising that this is having a wide range of effects including:

Acidification of our marine environment has a range of consequences. One of these is that it affects the ability of mollusc species, such as mussels and oysters, to develop their protective shells by reducing the process of calcification. A pattern of increases in sea temperatures and intensity of storms have both indirect effects on our internationally important breeding seabirds through reductions in food availability and direct effects such as increases in the mortality of birds during extreme weather. For example, black-legged kittiwake, have declined by 70% since the mid-1980s, with the downward trend largely linked to a reduction in their main food supply, sandeels, as result of climate change.

waves breaking
©Susan Davies

Invasive non-native species

For many years, plants or animals have been brought to our shores by people through a range of different pathways, such as the movement of boats, equipment, goods or stock. These movements arise from both international trade and recreational and leisure activities. Where these species have a negative impact on our native wildlife or people’s well-being or the economy they are termed invasive. It is important to have protocols in place to detect and then respond to invasive species in our coastal and marine environments. The best line of defence is to try to prevent these invasive non-natives arriving in the first place by having appropriate biosecurity measures in place.

Examples of non-native invasive species around the UK include:

Pollution

Pollution comes in a variety of forms and from a variety of human sources both on land and at sea. It is estimated that 80% of all marine pollution comes from human activity on land and enters the sea through rivers and streams. This serves as a reminder of how our behaviours on land affects the quality of our marine environments. Examples of marine pollution include:

Development and exploitation

Our coastal and marine environments continue to placed under pressures from development and the exploitation of our natural resources, using these at levels beyond which they can naturally replenish.

Scallop dredger
© Susan Davies