Seaweed harvesting
Seaweeds can be harvested sustainably with appropriate site selection and management.
Seaweed functions
Kelp and other seaweeds play an important role in coastal and marine ecosystems. Providing food, shelter and a variety of ecosystem services. Kelps are ecosystem engineers and key marine habitats that support a diverse array of plants and animals. They provide nursery grounds for commercial fish and shellfish as well as foraging areas for birds. Seaweed, especially kelps, contribute to the ocean carbon and nutrient cycles and can also play a role in coastal protection.
Seaweeds are features of a number of protected areas and some are Priority Marine Features (PMFs) in their own right.
Seaweed vulnerabilities and pressures
The main threats to kelp beds are:
- ocean warming
- increased frequency and intensity of storms
- increased turbidity
- nutrient input from industrial runoff
- removal of top predators leading to overgrazing by fish, sea urchins, and other marine life.
Unsustainable harvesting can also be a threat to kelp. Dredging and mechanical harvest of seaweeds is largely banned in Scottish waters and generally, only collection by hand is allowed. Unsustainable harvesting is not currently considered to be a significant pressure in Scotland as harvesting is not widely practiced.
Sustainable management
Seaweeds can be harvested sustainably, but harvesting operations must take into account their important ecological functions and services. as well as their complex life histories.
Outcomes of unsustainable harvesting may include:
- damage to growing areas of individual plants, affecting regeneration and biodiversity of species that live in and on seaweed
- loss of seaweed as a habitat used by marine animals and plants
- opportunistic seaweeds outcompeting those that are harvested
- increased erosion
Commercial harvesting
Seaweeds have a range of commercial applications; these include their use in the food industry, fertilisers, textiles, pharmaceuticals and as a novel biofuel.
Our role in seaweed harvesting
NatureScot is not a regulatory body, we provide advice to regulators and stakeholders on activities including commercial harvesting, which are likely to impact on our natural heritage. We advise that any proposed commercial harvesting operation should develop a sustainable harvest strategy. Our sustainable harvest strategy standing advice provides further information.
Permission to harvest or take seaweed
Anyone seeking to harvest or take seaweed, should always seek the landowner's permission.
For anyone wanting to harvest or take seaweed from within a Site of Special Scientific Interest (SSSI), the relevant owners/occupiers may need to seek consent from NatureScot. This would depend on the features of the SSSI and on whether the removal or harvesting of seaweed from within the site is an "Operation Requiring Consent".
Crown Estate Scotland may issue licenses for seaweed harvesting proposals for the seabed and the foreshore under their ownership
If a proposal is to harvest from the seabed below the mean low water spring mark using a vessel, the applicant may require a marine licence. The requirement for a marine licence should be discussed with the regulator, Marine Directorate in the first instance. Marine Directorate Licensing Operations Team (MD LOT) can be contacted at: [email protected]
We work with Crown Estate Scotland and Marine Directorate to provide advice to inform licensing decisions for seaweed harvesting proposals. In advising regulators and harvesters, we consider the species, location, quantities in relation to the scale and regenerative capacity of seaweed species and methods (including time of year, harvesting methods, duration and timing of any proposed fallowing period). Depending on the scale of operations, we may advise a stock biomass assessment is required to establish a baseline of the available seaweed resource, together with a sustainable harvesting strategy.
Protected areas and features
In general, there is no presumption against sustainable seaweed harvesting in protected areas. However, the activity should be appropriately assessed to ensure it will not impact on relevant features of protected areas., NatureScot should be consulted on any commercial harvesting with connectivity to protected areas. To find out more about the locations and further information on protected areas (SSSIs, Special Areas of Conservation (SACs), Special Protected Areas (SPAs) and Marine Protected Areas (MPAs)), please visit our SiteLink facility.
Designated seal haul out sites provide additional protection for seals from intentional or reckless harassment. Seals are protected at these sites all year and may be impacted by activities associated with seaweed harvesting.
Priority Marine Features (PMFs) are a prioritised list of habitats and species of conservation importance which are afforded policy protection under the National Marine Plan. There are several types of seaweed habitats that are classified as PMFs.
If there is a concern that a proposal is likely to affect a protected area, PMF, seal haul out or a protected species, please consult NatureScot.
Contact
Our Area teams lead to provide our advice for seaweed harvesting. Any requests for advice should be made using our new InformedDECISION™ casework service
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