SeaCliffs, Vegetation, and Birds

Lecture 2

SeaCliffs, Vegetation, and Birds• Hard rock cliffs• Resistant bedrock (geology)• Also, Soft rock cliffs • Unconsolidated material

(glacial materials)• Hard rock: stable, steep• Soft rock: unstable, highly

erodable• Hard rock: ledges, thin soils• Soft rock: slippage, thicker

soils• http://coastal.er.usgs.gov/

navassa/geology/terraces2.html

SeaCliffs, Vegetation, and Birds

SeaCliffs, Vegetation, and Birds

• Hard rock: change is slow over time

• Soft rock: sudden, often large-scale change due to mass movement

• Cross-sections of Sea cliffs vary dependent on nature and resistance of the rock, aided by jointing and mineral ‘makeup’, processes of weathering, exposure to wind, rain and sea salt, and erosion through undercutting at the base

• Two examples: (1) hard rock (2) soft rock

SeaCliffs, Vegetation, and Birds

SeaCliffs, Vegetation, and Birds

SeaCliffs, Vegetation, and Birds

SeaCliffs, Vegetation, and Birds

SeaCliffs, Vegetation, and Birds

SeaCliffs, Vegetation, and Birdshttp://www.english-nature.org.uk/livingwiththesea/project_details/good_practice_guide/habitatcrr/ENRestore/Habitats/Seacliffs/States/Summary.htm

SeaCliffs, Vegetation, and Birds

• Vegetation on Hard rock cliffs depends on slope, depth of soil, presence of ledges (terraces), exposure to wind, rain and salt spray, as well as acidity of soil determined by the ‘parent material’ (rock)

• Exposure to oceanic swell, onshore winds, and storms leads to maritime vegetation

• Inland vegetation changes because more sheltered e.g. from salt spray

• In less exposed areas then dependent on acid or alkaline rocks/soils then may get acid grasslands and heath versus calcareous grasslands (chalk and other limestones)

• Less exposed cliffs may have scrub and woodland communities

• Often vegetation transitions (e.g. due to salt spray)

• If isolated (and free of human activity) then endemic species (intolerant of competition) e.g. Limonium spp.

SeaCliffs, Vegetation, and Birds• Dependent on the degree of

slope movement then may or may not have vegetation or animal life

• In very open areas then may be invertebrate life

• Where less movement then may have woodland, scrub and grassland

• Landslips lead to exposed soil/rock

• Succession of plants if fairly stable for a period of time

• Ephemeral plants and invertebrates

• Major cliff falls can lead to woodland if stable

Ephemeral refers to plants that are short-lived, grow and reproduce rapidly. Ephemeral soils are those develop quickly and disappear in short term cycles (Doody – Habitat Guide)

SeaCliffs, Vegetation, and Birds• Exposure to wind, salt spray is a

major determinant of vegetation communities

• Also, climatic effects• Vegetation contains plants (and

animals) that are mostly confined to coastal fringe

• Salt tolerant: Sedum rosea, Festuca rubra, Armeria maritima, Silene uniflora

• Halophytes: Crithmum maritimum, Limonium binervosum, Salicornia spp

• May also be some invasive species e.g. Carpobrotus edulis

• Etc……• See handout

See http://www.habitas.org.uk/

SeaCliffs, Vegetation, and Birds• Sea Cliffs provide breeding

and nesting for many birds• Location e.g. ledges/burrows

provide food source and protection

• Guillemot (Uria aalge)• Razorbill (Alca torda)• Kittiwake (Rissa trydactyla)• Shearwater (e.g. Manx

Shearwater Puffinus)• Puffin (Fratercula arctica)• Etc……

See http://www.birdguides.com/

SeaCliffs, Vegetation, and Birdshttp://www.oursouthwest.com/Wild_Hab/Coast%20and%20Marine/Sea%20cliff%20and%20slope/seacliff.htm

SeaCliffs, Vegetation, and Birds

http://www.nps.gov/goga/parklabs/library/wildlifeguide/wildlife_habitats.htm

http://www.swbiodiversity.org.uk/Habitats/Maritime/maritime_devon.htm

http://www.heritagecouncil.ie/publications/habitats/11.html

http://www.ukbap.org.uk/UKPlans.aspx?ID=27

http://www.nht.gov.au/nht1/programs/coastcare/50-ways.html

http://www.oblue.utvinternet.com/ob_irelands4.html