Shown here is a photograph taken on October 20, 2023, of a wild Elkhorn coral colony in Buck Island Reef National Monument, St. Croix, VI, showing the effects of heat stress caused by elevated ocean temperatures. The heat stress causes “coral bleaching,” or the loss of nutrient-giving microscopic algae that normally live within corals.
Ilsa B Kuffner, Ph.D.
Ilsa Kuffner is a Research Marine Biologist at the St. Petersburg Coastal and Marine Science Center in St. Petersburg, Florida.
As a research marine biologist for the Coastal and Marine Geology Program, I investigate the causes and effects of coral reef degradation. I explore local- to global-scale stressors on reefs, and experimentally determine how environmental variables such as sea-surface temperature, water quality, seawater chemistry, nuisance macroalgae, and ocean acidification affect coral growth, the community structure of reefs, and the process of reef building. My work informs resource managers about the mechanisms causing reef degradation and how management efforts may be improved to protect and restore degraded reefs. Please visit the USGS Coral Reef Ecosystems Studies (CREST) website for more information (see link below).
Science and Products
Coral Reef Ecosystem Studies (CREST)
The specific objectives of this project are to identify and describe the processes that are important in determining rates of coral-reef construction. How quickly the skeletons of calcifying organisms accumulate to form massive barrier-reef structure is determined by processes of both construction (how fast organisms grow and reproduce) and destruction (how fast reefs break down by mechanical...
Measuring Coral Growth to Help Restore Reefs
It is critical to start measuring calcification rates in a systematic way now, particularly at subtropical latitudes where conditions fluctuate seasonally, so that we can understand how dynamic ocean conditions affect calcifying organisms today and predict possible changes in the future. We established a calcification monitoring network in the Florida Keys and have been measuring calcification...
Local-scale ecosystem resilience amid global-scale ocean change: the coral reef example
Coral reefs are massive, wave resistant structures found throughout the tropics, where they have long attracted attention for their beauty, ecological importance, and rich biological diversity. However, in recent years attention to these systems has focused on their downturn in health and the potential that they effectively could disappear within a century. Yet while many coral reefs have deterio
Impact of Ocean Warming and Acidification on Growth of Reef-Building Corals
Coral reefs are some of the most biologically rich and economically valuable ecosystems in the world. They provide food, fishing, and recreation opportunities for millions of people, protect coastlines from storms, and shelter thousands of plant and animal species. However, climate change is contributing to the degradation of coral reefs in two significant ways: warming temperature and increasing
Filter Total Items: 24
Bleaching Elkhorn coral in Buck Island Reef National Monument
Shown here is a photograph taken on October 20, 2023, of a wild Elkhorn coral colony in Buck Island Reef National Monument, St. Croix, VI, showing the effects of heat stress caused by elevated ocean temperatures. The heat stress causes “coral bleaching,” or the loss of nutrient-giving microscopic algae that normally live within corals.
Bleached Elkhorn coral now under shade in Biscayne National Park
Shown here is a small colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Shown here is a small colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Elkhorn coral suffering from bleaching in Dry Tortugas National Park, Pulaski Shoal
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has succumbed to "bleaching," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has succumbed to "bleaching," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Divers putting shades over experimental Elkhorn corals in Biscayne National Park
Shown here are three SCUBA divers installing shade structures over experimental Elkhorn corals (Acropora palmata) that have become "bleached," that is, lost all their algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The corals are attached to cement blocks as part of the U.S.
Shown here are three SCUBA divers installing shade structures over experimental Elkhorn corals (Acropora palmata) that have become "bleached," that is, lost all their algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The corals are attached to cement blocks as part of the U.S.
Bleached Elkhorn coral under a shade in Dry Tortugas National Park, Garden Key
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Bleached Elkhorn coral under a shade in Dry Tortugas National Park, Pulaski Shoal
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Bleached Elkhorn coral in Dry Tortugas National Park
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, in Dry Tortugas National Park that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave.
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, in Dry Tortugas National Park that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave.
PubTalk-03/2023: Coral Reef in Crisis - Science to Guide Reef Restoration for Ecosystem Recovery
linkCoral Reef in Crisis - Science to Guide Reef Restoration for Ecosystem Recovery
By Ilsa Kuffner, Research Marine Biologist
USGS St. Petersburg Coastal & Marine Science Center
Learn About:
PubTalk-03/2023: Coral Reef in Crisis - Science to Guide Reef Restoration for Ecosystem Recovery
linkCoral Reef in Crisis - Science to Guide Reef Restoration for Ecosystem Recovery
By Ilsa Kuffner, Research Marine Biologist
USGS St. Petersburg Coastal & Marine Science Center
Learn About:
Elkhorn Coral Colonies
USGS studies the growth rates of corals at a network of coral growth assessment stations throughout Buck Island National Monument in St. Croix, U.S. Virgin Islands. These data provide resource managers with information needed to understand how coral populations are doing in the park.
USGS studies the growth rates of corals at a network of coral growth assessment stations throughout Buck Island National Monument in St. Croix, U.S. Virgin Islands. These data provide resource managers with information needed to understand how coral populations are doing in the park.
Successful experimental elkhorn coral colony in Dry Tortugas National Park
The U.S. Geological Survey is conducting research to guide the restoration and recovery of threatened corals in Dry Tortugas National Park and throughout the western Atlantic. Shown here is a colony of the threatened elkhorn coral, Acropora palmata, that has grown over the sides of a cinderblock experimental platform.
The U.S. Geological Survey is conducting research to guide the restoration and recovery of threatened corals in Dry Tortugas National Park and throughout the western Atlantic. Shown here is a colony of the threatened elkhorn coral, Acropora palmata, that has grown over the sides of a cinderblock experimental platform.
Successful experimental elkhorn coral colony in Dry Tortugas National Park
The U.S.
Three successful experimental coral colonies in Dry Tortugas National Park
The U.S. Geological Survey is conducting research to guide the restoration and recovery of threatened corals in Dry Tortugas National Park and throughout the western Atlantic. Shown here are two colonies of the threatened elkhorn coral, Acropora palmata, with a colony of staghorn coral, Acropora cervicornis, in the center.
The U.S. Geological Survey is conducting research to guide the restoration and recovery of threatened corals in Dry Tortugas National Park and throughout the western Atlantic. Shown here are two colonies of the threatened elkhorn coral, Acropora palmata, with a colony of staghorn coral, Acropora cervicornis, in the center.
SCUBA diving over a coral reef
Student contractor Erin Lyons swims over a coral reef during research surveys.
Student contractor Erin Lyons swims over a coral reef during research surveys.
Corals on a USGS calcification assessment station in Buck Island Reef National Monument
Established in 2009, the U.S. Geological Survey’s Coral Assessment Network (USGS-CAN) provides data on coral-growth (calcification) rates throughout the Florida Keys and St. Croix, U.S. Virgin Islands. Pictured here is one of 30 stations located in Buck Island Reef National Monument.
Established in 2009, the U.S. Geological Survey’s Coral Assessment Network (USGS-CAN) provides data on coral-growth (calcification) rates throughout the Florida Keys and St. Croix, U.S. Virgin Islands. Pictured here is one of 30 stations located in Buck Island Reef National Monument.
Coral Growth Experiment in Buck Island, St. Croix, USVI
USGS studies the growth rates of corals at a network of coral growth assessment stations throughout Buck Island National Monument in St. Croix, U.S. Virgin Islands. These data provide resource managers with information needed to understand how coral populations are doing in the park.
USGS studies the growth rates of corals at a network of coral growth assessment stations throughout Buck Island National Monument in St. Croix, U.S. Virgin Islands. These data provide resource managers with information needed to understand how coral populations are doing in the park.
USGS scuba diver on coral reef in Dry Tortugas National Park, FL, USA
The U.S. Geological Survey is conducting research to guide the recovery of the threatened Elkhorn coral, Acropora palmata, in Dry Tortugas National Park and throughout the western Atlantic.
The U.S. Geological Survey is conducting research to guide the recovery of the threatened Elkhorn coral, Acropora palmata, in Dry Tortugas National Park and throughout the western Atlantic.
Elkhorn Coral
The left panel shows the threatened elkhorn coral (Acropora palmata) alive and performing the critical ecosystem service of building the reef crest that protects shorelines during storms. The right panel shows a dead and quickly eroding skeleton of Elkhorn Coral.
The left panel shows the threatened elkhorn coral (Acropora palmata) alive and performing the critical ecosystem service of building the reef crest that protects shorelines during storms. The right panel shows a dead and quickly eroding skeleton of Elkhorn Coral.
USGS monitors growth rates of Elkhorn Coral
USGS monitors the growth rates of the threatened Elkhorn Coral (Acropora palmata) at Dry Tortugas National Park (pictured) and throughout the Florida Keys, U.S.A.
USGS monitors the growth rates of the threatened Elkhorn Coral (Acropora palmata) at Dry Tortugas National Park (pictured) and throughout the Florida Keys, U.S.A.
Reef erosion demonstrated by concrete and stainless-steel marker
Concrete and stainless-steel marker photographed 17 years after being installed into the reef in 1998 by Harold Hudson, NOAA. Scraping and grazing by parrotfish, chemical erosion from sponges, and wave action all combine to winnow away the dead skeletons of coral—a process known as reef erosion.
Concrete and stainless-steel marker photographed 17 years after being installed into the reef in 1998 by Harold Hudson, NOAA. Scraping and grazing by parrotfish, chemical erosion from sponges, and wave action all combine to winnow away the dead skeletons of coral—a process known as reef erosion.
Healthy Elkhorn Coral (Acropora palmata)
The survival of Elkhorn Coral, shown here composing a healthy thicket, is critical for shoreline protection because it is the only species that builds reef-crest habitat in the Caribbean region.
The survival of Elkhorn Coral, shown here composing a healthy thicket, is critical for shoreline protection because it is the only species that builds reef-crest habitat in the Caribbean region.
USGS Coral Reef Researcher
Don Hickey finishes installing ocean chemistry monitoring equipment on Sombrero Reef, Florida Keys.
Don Hickey finishes installing ocean chemistry monitoring equipment on Sombrero Reef, Florida Keys.
Science and Products
Coral Reef Ecosystem Studies (CREST)
The specific objectives of this project are to identify and describe the processes that are important in determining rates of coral-reef construction. How quickly the skeletons of calcifying organisms accumulate to form massive barrier-reef structure is determined by processes of both construction (how fast organisms grow and reproduce) and destruction (how fast reefs break down by mechanical...
Measuring Coral Growth to Help Restore Reefs
It is critical to start measuring calcification rates in a systematic way now, particularly at subtropical latitudes where conditions fluctuate seasonally, so that we can understand how dynamic ocean conditions affect calcifying organisms today and predict possible changes in the future. We established a calcification monitoring network in the Florida Keys and have been measuring calcification...
Local-scale ecosystem resilience amid global-scale ocean change: the coral reef example
Coral reefs are massive, wave resistant structures found throughout the tropics, where they have long attracted attention for their beauty, ecological importance, and rich biological diversity. However, in recent years attention to these systems has focused on their downturn in health and the potential that they effectively could disappear within a century. Yet while many coral reefs have deterio
Impact of Ocean Warming and Acidification on Growth of Reef-Building Corals
Coral reefs are some of the most biologically rich and economically valuable ecosystems in the world. They provide food, fishing, and recreation opportunities for millions of people, protect coastlines from storms, and shelter thousands of plant and animal species. However, climate change is contributing to the degradation of coral reefs in two significant ways: warming temperature and increasing
Filter Total Items: 24
Bleaching Elkhorn coral in Buck Island Reef National Monument
Shown here is a photograph taken on October 20, 2023, of a wild Elkhorn coral colony in Buck Island Reef National Monument, St. Croix, VI, showing the effects of heat stress caused by elevated ocean temperatures. The heat stress causes “coral bleaching,” or the loss of nutrient-giving microscopic algae that normally live within corals.
Shown here is a photograph taken on October 20, 2023, of a wild Elkhorn coral colony in Buck Island Reef National Monument, St. Croix, VI, showing the effects of heat stress caused by elevated ocean temperatures. The heat stress causes “coral bleaching,” or the loss of nutrient-giving microscopic algae that normally live within corals.
Bleached Elkhorn coral now under shade in Biscayne National Park
Shown here is a small colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Shown here is a small colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Elkhorn coral suffering from bleaching in Dry Tortugas National Park, Pulaski Shoal
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has succumbed to "bleaching," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has succumbed to "bleaching," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Divers putting shades over experimental Elkhorn corals in Biscayne National Park
Shown here are three SCUBA divers installing shade structures over experimental Elkhorn corals (Acropora palmata) that have become "bleached," that is, lost all their algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The corals are attached to cement blocks as part of the U.S.
Shown here are three SCUBA divers installing shade structures over experimental Elkhorn corals (Acropora palmata) that have become "bleached," that is, lost all their algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The corals are attached to cement blocks as part of the U.S.
Bleached Elkhorn coral under a shade in Dry Tortugas National Park, Garden Key
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Bleached Elkhorn coral under a shade in Dry Tortugas National Park, Pulaski Shoal
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave. The coral is attached to a cement block as part of the U.S.
Bleached Elkhorn coral in Dry Tortugas National Park
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, in Dry Tortugas National Park that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave.
Shown here is a colony of the threatened Elkhorn coral, Acropora palmata, in Dry Tortugas National Park that has become "bleached," that is, lost all its algal symbionts (also called zooxanthellae) because of the summer 2023 ocean-heat wave.
PubTalk-03/2023: Coral Reef in Crisis - Science to Guide Reef Restoration for Ecosystem Recovery
linkCoral Reef in Crisis - Science to Guide Reef Restoration for Ecosystem Recovery
By Ilsa Kuffner, Research Marine Biologist
USGS St. Petersburg Coastal & Marine Science Center
Learn About:
PubTalk-03/2023: Coral Reef in Crisis - Science to Guide Reef Restoration for Ecosystem Recovery
linkCoral Reef in Crisis - Science to Guide Reef Restoration for Ecosystem Recovery
By Ilsa Kuffner, Research Marine Biologist
USGS St. Petersburg Coastal & Marine Science Center
Learn About:
Elkhorn Coral Colonies
USGS studies the growth rates of corals at a network of coral growth assessment stations throughout Buck Island National Monument in St. Croix, U.S. Virgin Islands. These data provide resource managers with information needed to understand how coral populations are doing in the park.
USGS studies the growth rates of corals at a network of coral growth assessment stations throughout Buck Island National Monument in St. Croix, U.S. Virgin Islands. These data provide resource managers with information needed to understand how coral populations are doing in the park.
Successful experimental elkhorn coral colony in Dry Tortugas National Park
The U.S. Geological Survey is conducting research to guide the restoration and recovery of threatened corals in Dry Tortugas National Park and throughout the western Atlantic. Shown here is a colony of the threatened elkhorn coral, Acropora palmata, that has grown over the sides of a cinderblock experimental platform.
The U.S. Geological Survey is conducting research to guide the restoration and recovery of threatened corals in Dry Tortugas National Park and throughout the western Atlantic. Shown here is a colony of the threatened elkhorn coral, Acropora palmata, that has grown over the sides of a cinderblock experimental platform.
Successful experimental elkhorn coral colony in Dry Tortugas National Park
The U.S.
Three successful experimental coral colonies in Dry Tortugas National Park
The U.S. Geological Survey is conducting research to guide the restoration and recovery of threatened corals in Dry Tortugas National Park and throughout the western Atlantic. Shown here are two colonies of the threatened elkhorn coral, Acropora palmata, with a colony of staghorn coral, Acropora cervicornis, in the center.
The U.S. Geological Survey is conducting research to guide the restoration and recovery of threatened corals in Dry Tortugas National Park and throughout the western Atlantic. Shown here are two colonies of the threatened elkhorn coral, Acropora palmata, with a colony of staghorn coral, Acropora cervicornis, in the center.
SCUBA diving over a coral reef
Student contractor Erin Lyons swims over a coral reef during research surveys.
Student contractor Erin Lyons swims over a coral reef during research surveys.
Corals on a USGS calcification assessment station in Buck Island Reef National Monument
Established in 2009, the U.S. Geological Survey’s Coral Assessment Network (USGS-CAN) provides data on coral-growth (calcification) rates throughout the Florida Keys and St. Croix, U.S. Virgin Islands. Pictured here is one of 30 stations located in Buck Island Reef National Monument.
Established in 2009, the U.S. Geological Survey’s Coral Assessment Network (USGS-CAN) provides data on coral-growth (calcification) rates throughout the Florida Keys and St. Croix, U.S. Virgin Islands. Pictured here is one of 30 stations located in Buck Island Reef National Monument.
Coral Growth Experiment in Buck Island, St. Croix, USVI
USGS studies the growth rates of corals at a network of coral growth assessment stations throughout Buck Island National Monument in St. Croix, U.S. Virgin Islands. These data provide resource managers with information needed to understand how coral populations are doing in the park.
USGS studies the growth rates of corals at a network of coral growth assessment stations throughout Buck Island National Monument in St. Croix, U.S. Virgin Islands. These data provide resource managers with information needed to understand how coral populations are doing in the park.
USGS scuba diver on coral reef in Dry Tortugas National Park, FL, USA
The U.S. Geological Survey is conducting research to guide the recovery of the threatened Elkhorn coral, Acropora palmata, in Dry Tortugas National Park and throughout the western Atlantic.
The U.S. Geological Survey is conducting research to guide the recovery of the threatened Elkhorn coral, Acropora palmata, in Dry Tortugas National Park and throughout the western Atlantic.
Elkhorn Coral
The left panel shows the threatened elkhorn coral (Acropora palmata) alive and performing the critical ecosystem service of building the reef crest that protects shorelines during storms. The right panel shows a dead and quickly eroding skeleton of Elkhorn Coral.
The left panel shows the threatened elkhorn coral (Acropora palmata) alive and performing the critical ecosystem service of building the reef crest that protects shorelines during storms. The right panel shows a dead and quickly eroding skeleton of Elkhorn Coral.
USGS monitors growth rates of Elkhorn Coral
USGS monitors the growth rates of the threatened Elkhorn Coral (Acropora palmata) at Dry Tortugas National Park (pictured) and throughout the Florida Keys, U.S.A.
USGS monitors the growth rates of the threatened Elkhorn Coral (Acropora palmata) at Dry Tortugas National Park (pictured) and throughout the Florida Keys, U.S.A.
Reef erosion demonstrated by concrete and stainless-steel marker
Concrete and stainless-steel marker photographed 17 years after being installed into the reef in 1998 by Harold Hudson, NOAA. Scraping and grazing by parrotfish, chemical erosion from sponges, and wave action all combine to winnow away the dead skeletons of coral—a process known as reef erosion.
Concrete and stainless-steel marker photographed 17 years after being installed into the reef in 1998 by Harold Hudson, NOAA. Scraping and grazing by parrotfish, chemical erosion from sponges, and wave action all combine to winnow away the dead skeletons of coral—a process known as reef erosion.
Healthy Elkhorn Coral (Acropora palmata)
The survival of Elkhorn Coral, shown here composing a healthy thicket, is critical for shoreline protection because it is the only species that builds reef-crest habitat in the Caribbean region.
The survival of Elkhorn Coral, shown here composing a healthy thicket, is critical for shoreline protection because it is the only species that builds reef-crest habitat in the Caribbean region.
USGS Coral Reef Researcher
Don Hickey finishes installing ocean chemistry monitoring equipment on Sombrero Reef, Florida Keys.
Don Hickey finishes installing ocean chemistry monitoring equipment on Sombrero Reef, Florida Keys.