Marine Invertebrate Diseases Active
Growth anomaly
Trematodiasis
Tissue loss
Black band disease
Coral reefs worldwide are under tremendous stress primarily due to human activities along the coasts. While climate change, over fishing, and coastal development have been implicated as a major cause of coral reef decline, diseases seem to play an increasing role.
Coral reefs are a constant struggle between slow growing corals and fast growing algae, and urchins play a critical role in maintaining that balance given their roles as important grazers. Unfortunately, we have little idea of what drives declines of urchins on reefs, and even fewer clues as to the causes of coral diseases.
Surveillance
We are applying methods used in investigation of animal diseases to corals and urchins. This begins with systematic descriptions of lesions at the gross and microscopic level. For instance, corals respond to insults in one of three basic ways:
1) Discoloration where there is a change in color from normal in the coral tissue. While this often applies to what is known as bleaching (loss of pigmentation and symbiotic algae in the tissues revealing the white skeleton underneath), it can apply to any coral manifesting areas of tissue discoloration (pallor, complete loss of pigment, or change in pigmentation).
2) Another response is tissue loss where there is absence of tissue revealing bare or algae covered skeleton.
The USGS National Wildlife Health Center in collaboration with NOAA and other partners is currently responding to the Florida Reef Tract coral disease outbreak, a disease event affecting the continental United States' only living barrier reef. Learn more about the Florida Reef Track Coral Disease Outbreak.
3) Finally, there are growth anomalies manifesting as abnormal growth of skeleton or tissue. Gross observations are complemented by microscopic examination of tissues.
As for urchins, we are trying to get a better idea of how to monitor their health from a biomedical perspective.
Research
Applying these tools to corals reveals that they, like other animals, are prone to a variety of infectious and non-infectious causes of mortality such as fungi, algae, cyanobacteria, parasitic corals, and ciliates. A significant challenge now is better characterization of host response at the light and electron microscope level along with development of cell markers to better understand pathogenesis of disease. For urchins, we are getting a handle on basic information such as gross and microscopic anatomy and how cells respond to insults.
Resources
Collecting corals for histopathology. A practical guide (English language edition) (Spanish language edition)
Histology Manual for Tripneustes gratilla (Collector Urchin)
Coral Disease Cards: In collaboration with various partners, we have made underwater cards that will help divers describe lesions in corals from Hawaii, American Samoa, and New Caledonia. The cards can be printed on underwater paper or laminated to help divers describe lesions in corals (cards designed to print front to back).
- Coral disease cards American Samoa
- Coral disease cards Hawaii
- Coral disease cards New Caledonia (English language edition)
- Coral Disease cards New Caledonia (French language edition)
Below are publications associated with this topic.
The first cyanobacterial infection of crustose coralline algae discovered on the reefs of Pohnpei, Micronesia
To understand coral disease, look at coral cells
Microbial aggregates within tissues infect a diversity of corals throughout the Indo-Pacific
Lectins stain cells differentially in the coral, Montipora capitata
Ocean warming and acidification have complex interactive effects on the dynamics of a marine fungal disease
Histological observations in the Hawaiian reef coral, Porites compressa, affected by Porites bleaching with tissue loss
Tissue loss (white syndrome) in the coral Montipora capitata is a dynamic disease with multiple host responses and potential causes
Bacterial communities associated with healthy and Acropora white syndrome-affected corals from American Samoa
Pathology of tissue loss (white syndrome) in Acropora sp. corals from the Central Pacific
Gross and microscopic morphology of lesions in Cnidaria from Palmyra Atoll, Central Pacific
Growth anomalies on the coral genera Acropora and Porites are strongly associated with host density and human population size across the Indo-Pacific
Coral diversity and the severity of disease outbreaks: a cross-regional comparison of Acropora white syndrome in a species-rich region (American Samoa) with a species-poor region (Northwestern Hawaiian Islands).
- Overview
Coral reefs worldwide are under tremendous stress primarily due to human activities along the coasts. While climate change, over fishing, and coastal development have been implicated as a major cause of coral reef decline, diseases seem to play an increasing role.
Coral reefs are a constant struggle between slow growing corals and fast growing algae, and urchins play a critical role in maintaining that balance given their roles as important grazers. Unfortunately, we have little idea of what drives declines of urchins on reefs, and even fewer clues as to the causes of coral diseases.
Surveillance
We are applying methods used in investigation of animal diseases to corals and urchins. This begins with systematic descriptions of lesions at the gross and microscopic level. For instance, corals respond to insults in one of three basic ways:
1) Discoloration where there is a change in color from normal in the coral tissue. While this often applies to what is known as bleaching (loss of pigmentation and symbiotic algae in the tissues revealing the white skeleton underneath), it can apply to any coral manifesting areas of tissue discoloration (pallor, complete loss of pigment, or change in pigmentation).
2) Another response is tissue loss where there is absence of tissue revealing bare or algae covered skeleton.
The USGS National Wildlife Health Center in collaboration with NOAA and other partners is currently responding to the Florida Reef Tract coral disease outbreak, a disease event affecting the continental United States' only living barrier reef. Learn more about the Florida Reef Track Coral Disease Outbreak.
3) Finally, there are growth anomalies manifesting as abnormal growth of skeleton or tissue. Gross observations are complemented by microscopic examination of tissues.
As for urchins, we are trying to get a better idea of how to monitor their health from a biomedical perspective.
Research
Applying these tools to corals reveals that they, like other animals, are prone to a variety of infectious and non-infectious causes of mortality such as fungi, algae, cyanobacteria, parasitic corals, and ciliates. A significant challenge now is better characterization of host response at the light and electron microscope level along with development of cell markers to better understand pathogenesis of disease. For urchins, we are getting a handle on basic information such as gross and microscopic anatomy and how cells respond to insults.
Resources
Collecting corals for histopathology. A practical guide (English language edition) (Spanish language edition)
Histology Manual for Tripneustes gratilla (Collector Urchin)
Coral Disease Cards: In collaboration with various partners, we have made underwater cards that will help divers describe lesions in corals from Hawaii, American Samoa, and New Caledonia. The cards can be printed on underwater paper or laminated to help divers describe lesions in corals (cards designed to print front to back).
- Coral disease cards American Samoa
- Coral disease cards Hawaii
- Coral disease cards New Caledonia (English language edition)
- Coral Disease cards New Caledonia (French language edition)
- Publications
Below are publications associated with this topic.
Filter Total Items: 36The first cyanobacterial infection of crustose coralline algae discovered on the reefs of Pohnpei, Micronesia
Crustose coralline algae (CCA) can cover substantial areas on living reef benthos (Adey et al. 1982, Keats et al. 1997), are important to reef integrity by acting to cement reefs together (Littler and Littler 1984), and serve as recruitment sites for coral larvae (Lasker and Kim 1996, Harrington et al. 2004, Price 2010).AuthorsGreta S. Aeby, Thierry M. Work, Konrad A. HughenTo understand coral disease, look at coral cells
Diseases threaten corals globally, but 40 years on their causes remain mostly unknown. We hypothesize that inconsistent application of a complete diagnostic approach to coral disease has contributed to this slow progress. We quantified methods used to investigate coral disease in 492 papers published between 1965 and 2013. Field surveys were used in 65% of the papers, followed by biodetection (43%AuthorsThierry M. Work, Carol U. MeteyerMicrobial aggregates within tissues infect a diversity of corals throughout the Indo-Pacific
Coral reefs are highly diverse ecosystems where symbioses play a pivotal role. Corals contain cell-associated microbial aggregates (CAMA), yet little is known about how widespread they are among coral species or the nature of the symbiotic relationship. Using histology, we found CAMA within 24 species of corals from 6 genera from Hawaii, American Samoa, Palmyra, Johnston Atoll, Guam, and AustraliaAuthorsThierry M. Work, Greta S. AebyLectins stain cells differentially in the coral, Montipora capitata
A limitation in our understanding of coral disease pathology and cellular pathogenesis is a lack of reagents to characterize coral cells. We evaluated the utility of plant lectins to stain tissues of a dominant coral, Montipora capitata, from Hawaii. Of 22 lectins evaluated, nine of these stained structures in the upper or basal body wall of corals. Specific structures revealed by lectins that werAuthorsThierry M. Work, Yael FarahOcean warming and acidification have complex interactive effects on the dynamics of a marine fungal disease
Diseases threaten the structure and function of marine ecosystems and are contributing to the global decline of coral reefs. We currently lack an understanding of how climate change stressors, such as ocean acidification (OA) and warming, may simultaneously affect coral reef disease dynamics, particularly diseases threatening key reef-building organisms, for example crustose coralline algae (CCA).AuthorsGareth J. Williams, Nichole N. Price, Blake Ushijima, Greta S. Aeby, Sean M. Callahan, Simon K. Davy, Jamison M. Gove, Maggie D. Johnson, Ingrid S. Knapp, Amanda Shore-Maggio, Jennifer E. Smith, Patrick Videau, Thierry M. WorkHistological observations in the Hawaiian reef coral, Porites compressa, affected by Porites bleaching with tissue loss
The scleractinian finger coral Porites compressa is affected by the coral disease Porites bleaching with tissue loss (PBTL). This disease initially manifests as bleaching of the coenenchyme (tissue between polyps) while the polyps remain brown with eventual tissue loss and subsequent algal overgrowth of the bare skeleton. Histopathological investigation showed a loss of symbiont and melanin-contaiAuthorsM. Sudek, Thierry M. Work, G.S. Aeby, S.K. DavyTissue loss (white syndrome) in the coral Montipora capitata is a dynamic disease with multiple host responses and potential causes
Tissue loss diseases or white syndromes (WS) are some of the most important coral diseases because they result in significant colony mortality and morbidity, threatening dominant Acroporidae in the Caribbean and Pacific. The causes of WS remain elusive in part because few have examined affected corals at the cellular level. We studied the cellular changes associated with WS over time in a dominantAuthorsThierry M. Work, Robin Russell, Greta S. AebyBacterial communities associated with healthy and Acropora white syndrome-affected corals from American Samoa
Acropora white syndrome (AWS) is characterized by rapid tissue loss revealing the white underlying skeleton and affects corals worldwide; however, reports of causal agents are conflicting. Samples were collected from healthy and diseased corals and seawater around American Samoa and bacteria associated with AWS characterized using both culture-dependent and culture-independent methods, from coralAuthorsBryan Wilson, Greta S. Aeby, Thierry M. Work, David G. BournePathology of tissue loss (white syndrome) in Acropora sp. corals from the Central Pacific
We performed histological examination of 69 samples of Acropora sp. manifesting different types of tissue loss (Acropora White Syndrome-AWS) from Hawaii, Johnston Atoll and American Samoa between 2002 and 2006. Gross lesions of tissue loss were observed and classified as diffuse acute, diffuse subacute, and focal to multifocal acute to subacute. Corals with acute tissue loss manifested microscopicAuthorsThierry M. Work, Greta S. AebyGross and microscopic morphology of lesions in Cnidaria from Palmyra Atoll, Central Pacific
We conducted gross and microscopic characterizations of lesions in Cnidaria from Palmyra Atoll, Central Pacific. We found growth anomalies (GA) to be the most commonly encountered lesion. Cases of discoloration and tissue loss were rare. GAs had a focal or multi-focal distribution and were predominantly nodular, exophytic, and umbonate. In scleractinians, the majority of GAs manifested as hyperplaAuthorsGareth J. Williams, Thierry M. Work, Greta S. Aeby, Ingrid S. Knapp, Simon K. DavyGrowth anomalies on the coral genera Acropora and Porites are strongly associated with host density and human population size across the Indo-Pacific
Growth anomalies (GAs) are common, tumor-like diseases that can cause significant morbidity and decreased fecundity in the major Indo-Pacific reef-building coral genera, Acropora and Porites. GAs are unusually tractable for testing hypotheses about drivers of coral disease because of their pan-Pacific distributions, relatively high occurrence, and unambiguous ease of identification. We modeled mulAuthorsGreta S. Aeby, Gareth J. Williams, Erik C. Franklin, Jessica Haapkyla, C. Drew Harvell, Stephen Neale, Cathie A. Page, Laurie Raymundo, Bernardo Vargas-Angel, Bette L. Willis, Thierry M. Work, Simon K. DavyCoral diversity and the severity of disease outbreaks: a cross-regional comparison of Acropora white syndrome in a species-rich region (American Samoa) with a species-poor region (Northwestern Hawaiian Islands).
The dynamics of the coral disease, Acropora white syndrome (AWS), was directly compared on reefs in the species-poor region of the Northwestern Hawaiian Islands (NWHI) and the species-rich region of American Samoa (AS) with results suggesting that biodiversity, which can affect the abundance of susceptible hosts, is important in influencing the impacts of coral disease outbreaks. The diversity-disAuthorsG.S. Aeby, D.G. Bourne, B. Wilson, Thierry M. Work