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Shifting Baselines

Coral-Algal Phase Shift

There is no such thing as a pristine coral reef left in the world. All regions show some sign of impact and decline leaving regions impacted with extreme cases fringing on ecological extinction (Pandolfi et al. 2003). Studies estimate a 30% reduction in global coral coverage in the last three decades with projections reaching as high as 60% by 2030 (Wilkinson 2002). Coral reef degradation is matched with an increase in abundance of macroalgae (McCook 1999). Continual stress by such variables as human activity, diseases and natural impacts such as hurricanes may eventually result in a phase shift of the system, going from coral dominated to macroalgae (Hughes et al. 2003). The following footage illustrates a phase shift in the Central Pacific. Neighboring islands within the Line-Islands archipelago. An area previously analogous with high coral coverage was eventually dominated with fleshy macroalgae with the inability to recover.

Credits
Cinematography: Dr. Forest Rohwer
Edited by: Neilan Kuntz
Written by: Neilan Kuntz
Location: Palmyra Atoll, Line Islands, Central Pacific (2005)

Hughes et al. (2003) Climate Change, Human Impacts, and the Resilience of Coral Reefs. Science 301: 929-933.

McCook L.J. (1999). Macroalgae, nutrients and phase shifts on coral reefs: scientific issues and management consequences for the Great Barrier Reef. Coral Reefs 18: 357-367.

Pandolfi J.M. et al. (2003) Global Trajectories of the Long-Term Decline of Coral Reef Ecosystems. Science 301: 955-958.

Wilkinson C. (ed.) 2002 Status of coral reefs of the world: 2002. Australian Institute of Marine Science, Townsville, Australia.


Healthy vs. Impacted

On a global scale there is an accelerated deterioration in the health and status of coral reefs. For example, an estimated 30% of all reefs are already severely damaged. Based on present trends it is estimated that as much as 60% may be lost by 2030 (Wilkinson 2002). In addition to the corals themselves the associated organisms that depend on reef habitat will be lost due to the deterioration of the system. (Jackson & Sala 2001). An overall estimated biodiversity of reef associated organisms range from 1-9 million (Reaka-Kudla 1997). Consequently, reef habitat loss corresponds directly to the loss of associated organism and the network of marine life that is dependant on the reefs. The following footage compares several reefs within the same region, some of which are relatively healthy reefs whilst others have collapsed. The video footage demonstrates the co-dependency between coral reefs and their associated organisms at multiple levels and how deteriorating reefs have extremely low biodiversity.

Credits
Cinematography: Dr. Forest Rohwer & Dr. Stuart Sandin
Edited by: Neilan Kuntz
Written by: Neilan Kuntz
Location: Borneo, Malaysia (Sipadan) (2003)
Palmyra Atoll, Line Islands, Central Pacific (2004)

Jackson, J. B. C., E. Sala (2001) Unnatural Oceans. Scientia Marina 65(Suppl. 2): 273-281.

Reaka-Kadula, M. L. (1997) In: Biodiversity II: Understanding and Protecting Our Biological Resources. Eds. Reaka-Kudla, M. L., Wilson, D. E. and Wilson, E. O. (Joseph Henry Press, Washington, DC), pp 83-108.

Wilkinson, C. (2002) In: Status of the coral reefs of the world. G. C. R. M. Network [Ed.]. Australian Institute of Marine Science.


Common Sea Fan

Sightings of what was once as widespread as their common name suggest, fields of the Caribbean Common Sea Fan, gorgonia ventalina, have been replaced by the occasional solitary individual. This die-off has been largely due to the fungal disease, Aspergillosis; a land-based fungus that enters the marine environment via storm water run off and by atmospheric deposition.












Credits
Cinematography: Dr. Stuart Sandin & Neilan Kuntz
Edited by: Neilan Kuntz
Written by: Neilan Kuntz
Location: Bocas del Toro, Panama (2005)
Bonaire Island, Dutch Territory (2003)

Kim K, CD Harvell, PD Kim, GW Smith, SM Merkel (2000) Fungal disease resistance of Caribbean sea fan corals (Gorgonian spp.) Marine Biology 136: 259-267.

Sánchez JA, S Zea, JM Díaz (1998) Patterns of Octocoral and Black coral distribution in the oceanic barrier reef-complex of Providencia Island, Southwestern Caribbean. Caribbean Journal of Science 34:250-264.

Slattery M (1999) Fungal pathogenesis of the sea fan Gorgonia ventalina: direct and indirect consequences. Chemoecology 9:97-104


Acropora

Acropora palmata (elkhorn coral) and Acropora cervicornis (staghorn coral) have been two of the most important framework builders in the Caribbean throughout the Pleistocene and Holocene (Jackson 1992, Aronson & Precht 2001). The Acroporids have gone through an unprecedented die-off on a regional scale in the Caribbean in the last three decades (Aronson & Precht 2001). For example, a remote reef atoll located 30 km offshore from the coast of Belize, Central America, experienced a 99% loss in its Acropora spp. since the mid-seventies (McClanahan & Muthiga 1998). A. palmata was principle framework builder at the reef crest and shallow depths were the majority of wave energy passes, whilst A. cervicornis was predominant at intermediate depths. Coral diseases such as white band disease, affecting both species, and white pox disease, found to only affect A. palmata*, have been implicated in the regional decline of these ecologically important corals (Aronson & Pretch 2001). The following footage contrasts healthy and collapsed reefs of both Acropora species.

Credits
Cinematography: Neilan Kuntz
Edited by: Neilan Kuntz
Written by: Dr. Olga Pantos
Location: Bocas del Toro, Panama (2003)

Aronson, R. B., W. F. Pretch (2001) White-band disease and the changing face of Caribbean coral reefs. Hydrobiologia 460; 25-38.

Jackson, J.B.C. (1992) Pleistocene perspectives of coral reef community structure. American Zoologist 32: 719-731.

McClanahan, T.R., N.A., Muthiga (1998) An ecological shift in a remote coral atoll of Belize over 25 years. Environmental Conservation 25: 122-130.