Mesophotic Coral Ecosystems

Found between the more familiar shallow water coral habitat and the deep ocean is a relatively unknown and poorly understood depth realm referred to as the mesophotic zone -- "meso" for middle and "photic" for light. Mesophotic coral ecosystems (MCE) are characterized by the presence of light-dependent corals and associated communities typically found at depths ranging from 30-40 m and extending to over 100 m in the Gulf of Mexico.

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Content essays

Content essays are written by explorers involved in a specific expedition in order to provide further background on specific topic areas associated with the expedition.

Connecting the Dots: Understanding Coral Reef Connectivity

This essay discusses how coral reefs may be connected to one another. Does coral larvae stay close to home, move to a nearby neighborhood, or perhaps even travel hundreds of miles before settling in a new reef location?

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Understanding the Physical Connectivity of Reef Systems

This essay discusses how ocean currents around South Florida drive important physical connectivity between the coral reefs of Pulley Ridge, the Dry Tortugas, and the Florida Keys.

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Pulley Ridge: Looking Upstream to Protect Florida Keys National Marine Sanctuary

This essay introduces reasons why the proximity of Pulley Ridge to the Florida Keys National Marine Sanctuary, combined with the influence of the Loop Current, has led scientists to question whether Pulley Ridge could serve as an upstream source of invertebrate and fish larvae for the sanctuary.

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Mesophotic Coral Ecosystems

The term "coral" conjures up visions of warm, tropical waters, or, as of late, the cold dark depths of the ocean where not a ray of sunlight penetrates. Found between these two visions is a relatively unknown and poorly understood depth realm referred to as the mesophotic zone -- "meso" for middle and "photic" for light.

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About Pulley Ridge

This essay discusses the Pulley Ridge ecosystem, which is the deepest known photosynthetic coral reef off the continental U.S. It also describes the benthic and fish communities of this special region.

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Pacific Deep Reefs 2011 -- Mission Summary

This mission summary of an expedition to the deep reefs of the Pacific discusses how these communities are less impacted by stressors than their shallow-water counterparts and may represent important “seed-banks” for potential reef recovery.

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For each Ocean Explorer expedition, lessons are provided to support the content associated with the mission. You can visit our website here to search for lessons on a wide variety of deep-sea and open ocean topics. Use the search engine and see what you find on mesophotic corals. Here we provide you with some of our best mesophotic coral lessons.

A Piece of Cake

Grades: 5-6

Spatial heterogeneity in deep-water coral communities

Students will be able to explain what a habitat is, and describe at least three functions or benefits that habitats provide. Students will be able to describe some habitats that are typical of deep-water hard bottom communities. Students will be able to explain how organisms such as deep-water corals and sponges add to the variety of habitats in areas such as the Cayman Islands.

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Aliens on the Reef

Grades: 7-8

Focus: Impacts of invasive species on coral reefs

Students explain interactions between native coral reef species and invasive lionfish, and construct explanations that predict how these interactions may affect other ecosystems.

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Forests of the Deep Ocean

Grades: 9-12

Mapping Coral Reef Habitats

In this activity, students will be able to access data on selected coral reefs and manipulate these data to characterize these reefs, and explain the need for baseline data in coral reef monitoring programs. Students also will be able to identify and explain five ways that coral reefs benefit human beings, and identify and explain three major threats to coral reefs.

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Below are links to a few videos and images focused on deep-sea corals.

Past Ocean Exploration Expeditions Related to Mesophotic Corals

The above items are only a selection of mesophotic coral content on our website.

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