Cliffs - Threats

As cliffs are a static habitat, it is difficult to quantify changes in the amount of habitat as the extent of cliffs (i.e. length of coastline) is unlikely to change. However, the quality, structure, and stability of cliffs can come under pressure from climate change, agricultural activities, recreation, and coastal urban infrastructure and development (Jones et al, 2011).

Key Threat: Climate Change
The effects of climate change such as rising sea levels are having an impact on cliffs. Significant wave action and higher sea levels will lead to accelerated erosion of cliffs, particularly at the base of cliffs, potentially leading to cliff destabilisation and loss of rocky platforms (Jones et al, 2011; Jones et al, 2013). The vegetation found around cliffs is often specially adapted to exist in these extreme environments, tolerant to sea-spray and wind exposure. However cliff erosion from rising sea levels is leading to loss of vegetation and fragmentation of habitats (Burden et al, 2020).

Key Threat:  Cliff Protection/Stabilisation Measures
Around 18% of the UKs coastline has some form of artificial coastal protection (Jones et al, 2013). Cliffs are naturally a more linear and narrow habitat, and a stable coastline is required for activities such as agriculture, built infrastructure, recreation. However, the natural dynamics and services that cliffs provide (e.g. erosion, sediment supply, biological diversity) can conflict with these requirements (Jones et al, 2011). Influencing, changing, or stopping cliff natural dynamics through cliff protection or stabilisation measures can reduce erosion, benefitting human land use. However, it can have a knock-on impact on the quality and quantity of habitat available, or on other coastal margin habitats by reducing available sediment supply (Jones et al, 2011; Buglife, n.d.).

Key Threat: Human land use
Encroachment on cliff tops from intensive agriculture and urban development leaves narrow strips of fragmented habitat atop cliffs. The issue of the increased extent of human land use is exacerbated by the impacts of rising sea levels which are causing a coastal 'retreat'. This all results in a lack of space for cliff top habitats and vegetation to 'roll-back' into the landscape, negatively impacting the plants, invertebrates, and other wildlife which rely on clifftop habitats for breeding and feeding (Burden et al, 2020). The desire for more cliff protection measures to reduce erosion can stem from human land use and poorly planned developments (Buglife, n.d.). 

Management:
Hard cliffs generally require little direct management as they are a more robust habitat able to withstand higher levels of exposure and erosion. However, efforts can be made to plan development and land use that takes into account the current and future impacts of climate change - i.e. leaving space for nature and natural processes.