BankReefs: Difference between revisions

From coraldigest
Jump to: navigation, search
Line 9: Line 9:


=== Morphology and Ecology ===
=== Morphology and Ecology ===
Bank reefs are characterized by coral formations in linear or semi-circular clustered patterns that are often larger than similar coral formations such as [[PatchReefs|patch reefs]].<ref name= "cool">"Cool Things: Bank Reef." Web World Wonders. Apache, n.d. Web. 25 Feb. 2015. <http://webworld.freac.fsu.edu/cameras/keys/cool/bankreef.htm>.</ref> These coral formations typically consists of three regions that are distinct in their locations and the coral type from which they are formed.
Bank reefs are characterized by coral formations in linear or semi-circular clustered patterns that are often larger than similar coral formations such as [[PatchReefs|patch reefs]].<ref name= "cool">"Cool Things: Bank Reef." Web World Wonders. Apache, n.d. Web. 25 Feb. 2015. <http://webworld.freac.fsu.edu/cameras/keys/cool/bankreef.htm>.</ref> These coral formations typically consists of three regions classified by location and coral formation type.


The '''Reef Flat''' occupies the inshore side of the bank reef. This consists of broken coral skeletons and coralline algae to the exclusion of most other organisms due to the inhospitable heavy surf that often characterizes this area.<ref name= "cool"></ref>
The '''Reef Flat''' occupies the inshore side of the bank reef. This consists of broken coral skeletons and coralline algae to the exclusion of most other organisms due to the inhospitable heavy surf that often characterizes this area.<ref name= "cool"></ref>

Revision as of 01:45, 23 April 2017

Bank Reefs

Formation

Bank reefs, sometimes referenced as platform reefs, are built upward from the seafloor by non-photosynthetic coral. A single species often builds these deep-water reefs.[1] Photosynthesis is not typically the primary energy source for these systems, as they exist at depths to which sunlight cannot effectively penetrate.[1] Once the reefs reach an adequate depth, depending on local factors such clarity of water, photosynthetic coral species may also begin colonizing and expanding these reef formations.

Morphology and Ecology

Bank reefs are characterized by coral formations in linear or semi-circular clustered patterns that are often larger than similar coral formations such as patch reefs.[2] These coral formations typically consists of three regions classified by location and coral formation type.

The Reef Flat occupies the inshore side of the bank reef. This consists of broken coral skeletons and coralline algae to the exclusion of most other organisms due to the inhospitable heavy surf that often characterizes this area.[2]

The next adjacent section is the Spur and groove patterned region. Spurs are low ridges of coral. These areas are dominated by fire corals and zoanthids at shallower depths. At around 5-6 feet these species give way to elkhorn, star, and brain corals along with sea fans, seawhips, and sea plumes.[3] These spurs are formed through coral growth with Elkhorn coral playing a predominant role in reef expansion, growing at a rate of 4-5 inches a year.[2] Grooves are the sandy bottom channels that separate the spurs. These areas consist mostly coarse white limestone sand composed of fragments of shells, coral, and algae plates formed by green calcareous algae.[3][2] These regions are inhabited by smaller invertebrates that bury into the sand and only venture out at night.[3]

The final section of these coral reef formations is the Forereef. This is the open-sea edge of the bank reef. At its shallowest points this section of the reef if composed primarily of Star coral and inhabited by benthic (residing on rock or sediment) organisms.[3] As depth continues to increase and becomes limiting, coral begins to form plate-like formations that increase their surface area and photosynthetic ability.[3] From here the bank reef slopes down into the depths of the ocean until sponges and non-reef building community compose the majority of the ecosystem.[3]

As is typical of most coral reefs, bank reefs have a high species diversity living in and around them. French Angelfish (Pomacanthus paru), Blue Parrotfish (Scarus coeruleus), Queen Parrotfish (Scarus vetula), Queen triggerfish (Balistes vetula), Rock beauties (Holacanthus tricolor), Goatfish (Parupeneus cyclostomus), Porkfish (Anisotremus virginicus), and Snappers (Lutjanus spp.) commonly inhabit these coral formations.[3] Crabs, lobsters, sea urchins, and other organisms are also known to reside in the small caves and tunnels that form throughout the Bank reef structure.[2]

Location

Bank reefs are unique in that they are found at deeper depths than other coral formations, typically residing at a depth 20-60 feet.[4] An example of one such formation is off the central east coast of Florida. Here Oculina varicosa is known to form bank reefs from the sea floor.[1] Two bank reefs of note that stand juxtaposed to one another are the Carysfort Reef and Looe Key Reef. Both are named for sailing vessels that wrecked and foundered at these sites, the HMS Carysfort and the HMS Looe respectively. Such shipwrecks inspired the construction of lighthouses that are often characteristic of bank reef formations.[2] The Carysfort Reef lies offshore of North Key Largo, exhibits a poorly formed spur-and-groove formation patterning and lies between a depth of 30 and 40 feet.[2] In contrast, the Looe Key reef exhibits a well formed spur-and-groove patterning and resides at a depth between 30 and 105 feet.[2]

Notes

  1. 1.0 1.1 1.2 Jaap, Walter C. "Corals and Coral Reefs." Water: Science and Issues 1 (2003): 212-20. GVRL. Cengage Learning. Web. 25 Feb. 2015.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 "Cool Things: Bank Reef." Web World Wonders. Apache, n.d. Web. 25 Feb. 2015. <http://webworld.freac.fsu.edu/cameras/keys/cool/bankreef.htm>.
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 "Bank Reef." South Florida Aquatic Environments. FLMNH Ichthyology Department, n.d. Web. 25 Feb. 2015. <https://www.flmnh.ufl.edu/fish/southflorida/coral/bankreef.html>.
  4. "Coral Reefs." Nature Foundation St. Maarten, 2009. Web. 25 Feb. 2015. <http://www.naturefoundationsxm.org/education/coral_reefs/coral_reefs.htm>.
Cookies help us deliver our services. By using our services, you agree to our use of cookies.