Habitat Destruction
Habitat damage, destruction or loss occurs when natural
events or human actions harm or kill plants and animals that are essential to
the habitat’s survival and regeneration. Habitat destruction can take place in
any area of the ocean and may have long-lasting or permanent effects if habitat
conditions physically or biologically prevent regeneration.
Soft Bottom [Subtidal] Habitats
Soft bottom environments include habitats where the seabed consists of fine grain sediments, mud and sand. Soft bottom habitats vary in terms of biodiversity and productivity, depending upon depth, light exposure, temperature, sediment grain size and abundance of microalgae and bacteria.
Soft bottom is the ocean’s largest habitat, forming the bottom of most of the continental shelves as well as vast expanses at depths of 3,000 to 6,000 m, which cover more than 60 percent of Earth’s surface (Snelgrove 2010; Ausubel et al. 2010)
Hard Bottom [Subtidal] Habitats
Hard bottom habitats underlie all soft bottoms and include all types of exposed rock or coral and associated flora and fauna. Hard bottom areas are located throughout the ocean, and include the mid-ocean ridge and seamounts, but are more frequently found near the coast. The term “hard bottom” also refers to man-made structures, including jetties and fabricated reefs.
Intertidal Habitats
Intertidal habitats are located between low and high tide lines and can be either soft or hard bottom. The area of an intertidal zone depends upon a given area’s tidal ranges and submarine topography. Exposure in low tide conditions and immersion in high means organisms in these habitats are affected by wave action, cyclic fluctuations of temperature, exposure to air, ambient light, and predation by terrestrial and marine species.
Soft Bottom [Subtidal] Habitats
Soft bottom environments include habitats where the seabed consists of fine grain sediments, mud and sand. Soft bottom habitats vary in terms of biodiversity and productivity, depending upon depth, light exposure, temperature, sediment grain size and abundance of microalgae and bacteria.
Soft bottom is the ocean’s largest habitat, forming the bottom of most of the continental shelves as well as vast expanses at depths of 3,000 to 6,000 m, which cover more than 60 percent of Earth’s surface (Snelgrove 2010; Ausubel et al. 2010)
Hard Bottom [Subtidal] Habitats
Hard bottom habitats underlie all soft bottoms and include all types of exposed rock or coral and associated flora and fauna. Hard bottom areas are located throughout the ocean, and include the mid-ocean ridge and seamounts, but are more frequently found near the coast. The term “hard bottom” also refers to man-made structures, including jetties and fabricated reefs.
Intertidal Habitats
Intertidal habitats are located between low and high tide lines and can be either soft or hard bottom. The area of an intertidal zone depends upon a given area’s tidal ranges and submarine topography. Exposure in low tide conditions and immersion in high means organisms in these habitats are affected by wave action, cyclic fluctuations of temperature, exposure to air, ambient light, and predation by terrestrial and marine species.
Causes & Impacts Of Habitat Destruction
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Which Goals Does This Affect?
How Was It Measured?
The subtidal soft bottom destruction proxy utilized global commercial catch data developed by the Sea Around Us project, based upon FAO and other source data, in order to determine catch (tonnes per year) from trawling for each year from 1950-2006. ‘Trawlable habitat’ within an EEZ was defined as shallow subtidal (0-60m) and outer shelf (60-200m) soft bottom habitat from Halpern et al (2008). Total trawled catch was divided by the total area of soft-bottom habitat to produce a measure of trawl intensity per unit area.
The subtidal hard bottom destruction proxy scored regions based upon data from Reefs at Risks Revisited, which recorded the presence of destructive artisanal blast and poison (cyanide) fishing on a country-level basis. Destructive artisanal fishing practices were given a maximum value of “1” and those areas under low threat were categorized as “0”. These data were not a perfect proxy, as they only cover coral reef habitats, however, suitable global data for additional hard bottom habitats were not available.
The intertidal habitat destruction proxy measured the coastal population density within 10 km of the coast based upon the assumption that the potential for intertidal habitat destruction was proportional to the density of human population living along the coast. Population density was extracted from the gridded population of the world dataset (CIESIN 2005), using only the UN-adjusted population counts and density for the most recent year, 2000.
The subtidal hard bottom destruction proxy scored regions based upon data from Reefs at Risks Revisited, which recorded the presence of destructive artisanal blast and poison (cyanide) fishing on a country-level basis. Destructive artisanal fishing practices were given a maximum value of “1” and those areas under low threat were categorized as “0”. These data were not a perfect proxy, as they only cover coral reef habitats, however, suitable global data for additional hard bottom habitats were not available.
The intertidal habitat destruction proxy measured the coastal population density within 10 km of the coast based upon the assumption that the potential for intertidal habitat destruction was proportional to the density of human population living along the coast. Population density was extracted from the gridded population of the world dataset (CIESIN 2005), using only the UN-adjusted population counts and density for the most recent year, 2000.
What Are The Impacts?
ECOLOGICAL IMPACT
Habitat
destruction can have a significant impact on marine biodiversity as species’ richness,
abundance, distribution, genetic variation and inter-population dynamics are
affected and entire ecosystems are altered by the loss of habitat.
Destructive fishing practices (e.g. dredging, bottom trawling, shrimp farming, dynamiting, and poisoning) can displace or destroy habitats, eliminating food, shelter and breeding grounds for numerous species and decreasing primary production due to increased sedimentation.
When seagrass, mangrove and salt marsh habitats are destroyed, they are no longer able to sequester carbon dioxide (CO2) from the atmosphere and significant amounts of CO2, released from stored carbon, are emitted back into the atmosphere.
Ships can damage habitats with their hulls, propellers and anchors.
Divers and snorkelers can damage habitats such as coral reefs and seagrasses when in direct contact (i.e. breaking and trampling).
The installation and maintenance of pipelines and fiber optic cables on the seafloor can damage marine ecosystems and result in sedimentation and pollution.
Destructive fishing practices (e.g. dredging, bottom trawling, shrimp farming, dynamiting, and poisoning) can displace or destroy habitats, eliminating food, shelter and breeding grounds for numerous species and decreasing primary production due to increased sedimentation.
When seagrass, mangrove and salt marsh habitats are destroyed, they are no longer able to sequester carbon dioxide (CO2) from the atmosphere and significant amounts of CO2, released from stored carbon, are emitted back into the atmosphere.
Ships can damage habitats with their hulls, propellers and anchors.
Divers and snorkelers can damage habitats such as coral reefs and seagrasses when in direct contact (i.e. breaking and trampling).
The installation and maintenance of pipelines and fiber optic cables on the seafloor can damage marine ecosystems and result in sedimentation and pollution.
HUMAN HEALTH IMPACT
Marine
plants and animals are an important biological source of unique chemicals with
potential for medical use.
More than half of all new cancer drug research is focused on marine organisms (Cesar et al. 2003).
Habitat destruction can result in a loss in commercially or recreationally important marine species, potentially impacting opportunities for exercise, relaxation or outdoor learning.
The destruction and loss of coastal habitats decreases shoreline protection, which can negatively impact human lives and property.
Habitat destruction can eliminate organisms that filter sediments and pollutants, reducing water quality and impacting human health.
More than half of all new cancer drug research is focused on marine organisms (Cesar et al. 2003).
Habitat destruction can result in a loss in commercially or recreationally important marine species, potentially impacting opportunities for exercise, relaxation or outdoor learning.
The destruction and loss of coastal habitats decreases shoreline protection, which can negatively impact human lives and property.
Habitat destruction can eliminate organisms that filter sediments and pollutants, reducing water quality and impacting human health.
ECONOMIC IMPACT
Loss
and destruction of habitat for commercially harvested species (food and natural
products) can reduce food and livelihood security.
Decreased shoreline protection due to habitat loss can affect coastal communities and industries that are exposed to climactic events (e.g. storms, floods).
Currently, half of the world population lives within 60 km of the ocean and three-quarters of the large cities are located by the coast. By 2020, it is projected that some 60 per cent of the world population (~ 6 billion) will live in coastal areas (Kennish 2002, in UNEP 2007).
Decreased shoreline protection due to habitat loss can affect coastal communities and industries that are exposed to climactic events (e.g. storms, floods).
Currently, half of the world population lives within 60 km of the ocean and three-quarters of the large cities are located by the coast. By 2020, it is projected that some 60 per cent of the world population (~ 6 billion) will live in coastal areas (Kennish 2002, in UNEP 2007).
What Has Been Done?
Community-Managed Mangrove Forests Provide Incentive & Inspiration
Established
in 1986, Leam Markham is a 235-acre community-managed mangrove forest and sea
grass conservation zone in the Trang Province in Thailand. Years of
collaboration between local conservationists, economists, scientists,
grassroots activists, students and citizens have protected mangrove forests
from logging, development and destruction for aquaculture, and seagrass beds
from damage by trawling, dynamite fishing and pushnets. Leam Markham’s success
has led to the introduction of an additional 10 community mangrove forests in
the area, where inter-village committees are responsible for overseeing the
sites and providing management for local resources.
This small fishing community on the Anduman coast relies on mangroves for their existence.Jim Enright/Marine Photobank
Destructive Fishing Reform Program in the Philippines
In
1986, a partnership between the Philippine government and the International
Marinelife Alliance (IMA) was created in order to promote public and government
awareness of the impacts of destructive fishing techniques (e.g. cyanide). The program worked to provide training,
establish monitoring teams, enforce restrictions and improve import/export
policies to promote sustainable practices.
A fishery enforcement patrol boat in Batangas Bay, Phillipines.© Wolcott Henry 2005/Marine Photobank
Get More Information
The United Nations Environment Programme (UNEP) GRID-Arendal
The UNEP supports informed decision-making
and promotes awareness regarding habitat destruction.
Oceana
Oceana works internationally to alleviate
problems including overfishing, acidification and habitat destruction through
policy-oriented campaigns.
Save our Seas Foundation
This foundation raises awareness regarding
the degradation of coastal ecosystems and supports marine research worldwide.
U.S. Office of Naval Research (ONR)
ONR provides a guide to several marine
habitats and addresses the impacts humans can have upon these environments.
References
Adam, P. Saltmarshes in a Time of Change. Environmental Conservation 29, 39–61 (2002).
Airoldi, L. Roles of Disturbance, Sediment Stress, and Substratum Retention on Spatial Dominance in Algal Turf. Ecology 79, 2759–2770 (1998).
Airoldi, Laura & Beck, Michael W. Loss, status and trends for coastal marine habitats of Europe. Oceanography and Marine Biology: An Annual Review 45, 345–405 (2007).
COML. First Census of Marine Life 2010: Highlights of a Decade of Discovery. 2010.
Barber,
C.V., & Pratt, V.R. Sullied seas: Strategies for combating cyanide fishing in southeast Asia and beyond. 57 (International Marinelife Alliance: Philippines, 2001).
Balata, D., Piazzi, L. & Benedetti-Cecchi, L. Sediment Disturbance and Loss of Beta Diversity on Subtidal Rocky Reefs. Ecology 88, 2455–2461 (2007).
Beatley, T. Protecting biodiversity in coastal environments: Introduction and overview. Coastal Management 19, 1–19 (1991).
BenedettiCecchi, L. et al. Predicting the consequences of anthropogenic disturbance: large-scale effects of loss of canopy algae on rocky shores. Mar Ecol Prog Ser 214, 137–150 (2001).
Britsch, Louis D. & Dunbar, J. B. Land loss rates: Louisiana coastal plain. Journal of Coastal Research 9, 324–338 (1993).
Britton-Simmons, K. H. Functional group diversity, resource preemption and the genesis of invasion resistance in a community of marine algae. OIKOS 113, 395–401 (2006).
Bryant, D., Burke, L., McManus, J., and
Spalding, M. (1998). Reefs at risk: A map-based indicator of threats to the
world's coral reefs. World Resources Institute, Washington, DC.
Bulleri, F., Benedetti-Cecchi, L.,
Acunto, S., Cinelli, F., & Hawkins, S.J., (2002). The influence of canopy
algae on vertical patterns of distribution of low-shore assemblages on rocky coasts in the northwest
Mediterranean. J. Exp. Mar. Biol. Ecol.
267, 89–106.
Burke, L.,
Reytar, K., Spalding, M., Perry, A. (2011). Reefs at Risk Revisited. World
Resources Institute, Washington, DC.
Cesar, H., Burke, L. & Pet-Soede, L. The Economics of Worldwide Coral Reef Degradation. 24 (Cesar Environmental Economics Consulting (CEEC): The Netherlands, 2003).
Ceccherelli, G., Piazzi, L. & Cinelli, F. Response of the non-indigenous Caulerpa racemosa (Forsskål) J. Agardh to the native seagrass Posidonia oceanica (L.) Delile: effect of density of shoots and orientation of edges of meadows. Journal of Experimental Marine Biology and Ecology 243, 227–240 (2000).
Crooks, S., Herr, D., Tamelander, J., Laffoley, Dan & Vandever, J. Mitigating climate change through restoration and management of coastal wetlands and near-shore marine ecosystems: Challenges and opportunities. 69 (World Bank Group: Washington D.C., United States, 2011).
Davison, I. R. & Pearson, G. A. Stress Tolerance in Intertidal Seaweeds. Journal of Phycology 32, 197–211 (1996).
Day, J. W. et al. Restoration of the Mississippi Delta: Lessons from Hurricanes Katrina and Rita. Science 315, 1679–1684 (2007).
Dayton, P. K., Tegner, M. J., Edwards, P. B. & Riser, K. L. Sliding baselines, ghosts, and reduced expectations in kelp forest communities. Ecological Applications 8, 309–322 (1998).
Diaz, R.
J. and Schaffner, L.C. (1990). The functional role of estuarine benthos. in M.
Haire and E. C. Krome (eds.), Perspectives on the Chesapeake Bay: Advances in
Estuarine Science. Chesapeake Bay Program, Chesapeake Research Consortium
Publication, Gloucester Point, VA. pp. 25-56.
Dobson, A. et al. Habitat Loss, Trophic Collapse, and the Decline of Ecosystem Services. Ecology 87, 1915–1924 (2006).
Edgar, G. J. & Shaw, C. The production and trophic ecology of shallow-water fish assemblages in southern Australia II. Diets of fishes and trophic relationships between fishes and benthos at Western Port, Victoria. Journal of Experimental Marine Biology and Ecology 194, 83–106 (1995).
Edgar, G. J. & Shaw, C. The production and trophic ecology of shallow-water fish assemblages in southern Australia III. General relationships between sediments, seagrasses, invertebrates and fishes. Journal of Experimental Marine Biology and Ecology 194, 107–131 (1995).
Elliott, M. & Cutts, N. D. Marine habitats: loss and gain, mitigation and compensation. Mar. Pollut. Bull. 49, 671–674 (2004).
Eriksson, B. K., Rubach, A. & Hillebrand, H. Biotic habitat complexity controls species diversity and nutrient effects on net biomass production. Ecology 87, 246–254 (2006).
Food and
Agriculture Organization of the United Nations. The World’s Mangroves 1980–2005. (Rome, Italy 2007).
Galil, B.S. Loss or gain? Invasive aliens and biodiversity in the Mediterranean Sea. Marine Pollution Bulletin 55, 314–322 (2007).
Giri, C. et al. Status and distribution of mangrove forests of the world using earth observation satellite data. Global Ecology and Biogeography 20, 154–159 (2011).
Graham, M. H. Effects of Local Deforestation on the Diversity and Structure of Southern California Giant Kelp Forest Food Webs. Ecosystems 7, 341–357 (2004).
Gray, J. S., Dayton, P., Thrush, S. & Kaiser, M. J. On effects of trawling, benthos and sampling design. Mar. Pollut. Bull. 52, 840–843 (2006).
Gray, J. S. Marine biodiversity: Patterns, threats and conservation needs. Biodiversity and Conservation 6, 153–175 (1997).
Guidetti, P., Fraschetti, S., Terlizzi, A. & Boero, F. Distribution patterns of sea urchins and barrens in shallow Mediterranean rocky reefs impacted by the illegal fishery of the rock-boring mollusc Lithophaga lithophaga. Marine Biology 143, 1135–1142 (2003).
Halpern, B. S. et al. A Global Map of Human Impact on Marine Ecosystems. Science 319, 948–952 (2008).
Heck Jr, K. L., Hays, G. & Orth, R. J. Critical evaluation of the nursery role hypothesis for seagrass meadows. Marine Ecology Progress Series 253, 123–136 (2003).
Jackson, J. B. C. et al. Historical Overfishing and the Recent Collapse of Coastal Ecosystems. Science 293, 629–637 (2001).
Jacquet, J. & Pauly, D. Funding Priorities: Big Barriers to Small-Scale Fisheries. Conservation Biology 22, 832–835 (2008).
Jones, C. G., Lawton, J. H. & Shachak, M. Organism as ecosystem engineers. OIKOS 69, (1994).
Karlson, K., Rosenberg, R. & Bonsdorff, Erik Temporal and spatial large-scale effects of eutrophication end oxygen deficiency on benthic fauna in Scandinavian and Baltic waters - a review. Oceanography and Marine Biology: an Annual Review 40, 427–489 (2002).
Karsten, U., Koch, S., West, J. A. & Kirst, G. O. Physiological responses of the eulittoral macroalga Stictosiphonia hookeri (Rhodomelaceae, Rhodophyta) from Argentina and Chile: salinity, light and temperature acclimation. European Journal of Phycology 31, 361–368 (1996).
Kennish, M. J. Environmental Threats and Environmental Future of Estuaries. Environmental Conservation 29, 78–107 (2002).
Keough, Michael J. & Quinn, G.P. Effects of periodic disturbances from trampling on rocky intertidal algal beds. Ecological Applications 8, 141–161 (1998).
Keyghobadi, N. The genetic implications of habitat fragmentation for animals. Canadian Journal of Zoology 85, 1049–1064 (2007).
Koslow, J. A. et al. Seamount benthic macrofauna off southern Tasmania: community structure and impacts of trawling. Mar Ecol Prog Ser 213, 111–125 (2001).
McKinney, M. L. & Lockwood, J. L. Biotic homogenization: a few winners replacing many losers in the next mass extinction. Trends in Ecology & Evolution 14, 450–453 (1999).
Naylor, R. L. et al. Effect of aquaculture on world fish supplies. Nature 405, 1017–1024 (2000).
Newell, R. C. Biology of Intertidal Animals. (Pisces Conservation Ltd: 2007).
National Research Council. Effects of trawling and dredging on
seafloor habitat. (National Academy of Sciences, Washington DC 2002).
Ofiara, D. D. & Seneca, J. J. Biological effects and subsequent economic effects and losses from marine pollution and degradations in marine environments: Implications from the literature. Mar. Pollut. Bull. 52, 844–864 (2006).
Olden, J. D., Poff, N. L., Douglas, M. R., Douglas, M. E. & Fausch, K. D. Ecological and evolutionary consequences of biotic homogenization. Trends in Ecology & Evolution 19, 18–24 (2004).
Reid, W. V., Mooney H.A., Cropper A.,
et al., Millennium Ecosystem Assessment: Ecosystems and Human Well-Being—Synthesis
Report. World Resources Institute, Washington, DC, 2005.
Scheibling, R. & Gagnon, P. Competitive interactions between the invasive green alga Codium fragile ssp tomentosoides and native canopy-forming seaweeds in Nova Scotia (Canada). Marine Ecology-Progress SeriesMarine Ecology-Progress Series 325, 1–14 (2006).
Schiel, D. R. & Taylor, D. I. Effects of trampling on a rocky intertidal algal assemblage in southern New Zealand. Journal of Experimental Marine Biology and Ecology 235, 213–235 (1999).
Smith, S. H. Cruise ships: A serious threat to coral reefs and associated organisms. Ocean and Shoreline Management 11, 231–248 (1988).
Snelgrove, P. V. R. Discoveries of the Census of Marine Life: Making Ocean Life Count. (Cambridge University Press: 2010).
Steneck, R. S. et al. Kelp Forest Ecosystems: Biodiversity, Stability, Resilience and Future. Environmental Conservation 29, 436–459 (2002).
Stillman & Somero Adaptation to temperature stress and aerial exposure in congeneric species of intertidal porcelain crabs (genus Petrolisthes): correlation of physiology, biochemistry and morphology with vertical distribution. J. Exp. Biol. 199, 1845–1855 (1996).
Thrush, S. F., Gray, J. S., Hewitt, J. E. & Ugland, K. I. Predicting the effects of habitat homogenization on marine biodiversity. Ecol Appl 16, 1636–1642 (2006).
Thrush, S. F. & Dayton, P. K. Disturbance to Marine Benthic Habitats by Trawling and Dredging: Implications for Marine Biodiversity. Annual Review of Ecology and Systematics 33, (2002).
Tomanek & Somero Evolutionary and acclimation-induced variation in the heat-shock responses of congeneric marine snails (genus Tegula) from different thermal habitats: implications for limits of thermotolerance and biogeography. J. Exp. Biol. 202, 2925–2936 (1999).
Underwood, A. J. Importance of experimental design in detecting and measuring stresses in marine populations. Journal of Aquatic Ecosystem Stress and Recovery 7, 3–24 (2000).
Underwood, A. J. Beyond BACI: the detection of environmental impacts on populations in the real, but variable, world. Journal of Experimental Marine Biology and Ecology 161, 145–178 (1992).
Underwood,
A.J. (2000a). Importance of
experimental design in detecting and measuring stresses in marine populations. Journal of Aquatic Ecosystem Stress and Recovery 7: 3–24.
Underwood,
A.J. Experimental ecology of rocky intertidal habitats: what are we learning? J. Exp. Mar. Biol. Ecol. 250, 51–76 (2000).
Valentine J.P. & Johnson C.R. Establishment of the introduced kelp Undaria pinnatifida in Tasmania depends on disturbance to native algal assemblages. Journal of Experimental Marine Biology and Ecology 295, 63–90 (2003).
Vernberg,
J.F. (1993). Salt-marsh processes: a Review. Environmental Toxicology and
Chemistry, 12(2):2167-2195.
Wahl, M.
(2009). Marine hard bottom communities: Patterns, dynamics, diversity, and
change. Ecological Studies Volume 206:
445 pages. Springer. ISBN 3540927034, 9783540927037
Wilkinson,
C. (ed) (2008). Status of Coral Reefs of the World: 2008. GCRMN/Australian
Institute of Marine Science.
Worthington, D.G., Ferrell, D.J.,
McNeill, S.E., & Bell, J.D. (1992). Effects of the shoot density of
seagrass on fish and decapods: Are correlation evident over larger spatial
scales. Marine Biology, 112,
139–146.
PHOTO(S): © Keith A. Ellenbogen