Herbivory: Difference between revisions
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=Herbivory= | =Herbivory= | ||
==Three Types of Herbivorous Fishes <ref name="Loic" /> == | ==Three Types of Herbivorous Fishes <ref name="Loic" /> == | ||
Reef fishes that are herbivores are typically invertebrates <ref name="Corn" />. There are three types of herbivorous fishes. These include territorial grazers, roving grazers, and scrapers. Territorial grazers are site-attached fish that actively defend their territories against other herbivores. One example of a territorial grazer is a damselfish. [[File: | Reef fishes that are herbivores are typically invertebrates <ref name="Corn" />. There are three types of herbivorous fishes. These include territorial grazers, roving grazers, and scrapers. Territorial grazers are site-attached fish that actively defend their territories against other herbivores. One example of a territorial grazer is a damselfish. [[File:Dfish.jpg|border|200px|Longfin Damselfish-Juvenile www.mediahex.com]] | ||
*Roving Grazers-mobile herbivores move around reefs in large schools feeding on macro algae and epilithic algae | *Roving Grazers-mobile herbivores move around reefs in large schools feeding on macro algae and epilithic algae | ||
*Scrapers-highly mobile fish consume epilithic algae and remove sediment by scraping limestone surface of reefs | *Scrapers-highly mobile fish consume epilithic algae and remove sediment by scraping limestone surface of reefs | ||
Revision as of 20:03, 14 April 2014
Herbivory
Three Types of Herbivorous Fishes [1]
Reef fishes that are herbivores are typically invertebrates [2]. There are three types of herbivorous fishes. These include territorial grazers, roving grazers, and scrapers. Territorial grazers are site-attached fish that actively defend their territories against other herbivores. One example of a territorial grazer is a damselfish. Longfin Damselfish-Juvenile www.mediahex.com
- Roving Grazers-mobile herbivores move around reefs in large schools feeding on macro algae and epilithic algae
- Scrapers-highly mobile fish consume epilithic algae and remove sediment by scraping limestone surface of reefs
- Examples-surgeonfish, butterflyfish, angelfish[2]
Feeding Habits of Herbivore Fish/How Food is Digested[2]
- Focus on enriched macrophytes
- Shallower reefs have more herbivorous fishes and increased grazing rates
- Some prey directly on Corals (parrotfish)[3]
- Feed on red, green, and brown macro algae[2]
- No teeth in jaws, rather pharyngeal teeth farther back
- Digestion- must break down complex polysaccharide cell wall
- Mechanical-stomach grinds the algal cells
- Chemical-use acid lysis in the stomach
- Enzymatic digestion-enzymes produced by gastrointestinal tract can further break down algal cells/ intestinal microbes are key
Benefits of Herbivore Fishes to Stability of Coral Reefs
- Help maintain coral dominated states
- Limit growth of macro algae that compete with coral space
- A decrease in herbivore fish can be linked to increase in macro algae and coral reef mortality (macroalgae and phytoplankton most significant primary producer in system)
- Facilitate maintenance of reefs in coral dominated states[1]
- Strong top down control of macroalgae
- Elimination of herbivore fish can negatively impact survival, growth, and recruitment of corals and increase in prevalence of coral diseases
- Alteration in consumer pressure will reduce coral reef resilience and increase probability that climate change, ocean acidification, etc. will drive reefs to state like algal domination
- Turf algae and upright macroalgae increase are due to herbivore exclusion[3]
- One of the most well known cases of overgrowth occurred in the Caribbean after a previously unseen disease virtually killed off the herbivorous sea urchin Diadema antillarum[2]
- Caused collapse of Caribbean reefs in this area
- Macroalgae became dominant
- Decrease in diversity
References
- ↑ 1.0 1.1 Loïc M. Thibaut, Sean R. Connolly, and Hugh P. A. Sweatman 2012. Diversity and stability of herbivorous fishes on coral reefs. **Ecology 93:891–901. http://dx.doi.org/10.1890/11-1753.1
- ↑ 2.0 2.1 2.2 2.3 2.4 Cornell University: College of Agriculture and Life Sciences, "Herbivory in Fish." Last modified 2014. Accessed February 23, 2014. http://micro.cornell.edu/research/epulopiscium/herbivory-fish.
- ↑ 3.0 3.1 Burkepile, Deron E. , and Mark E. Hay. "Nutrient versus herbivore control of macroalgal community development and coral growth on a Caribbean reef."Inter-Research Marine Ecology Progress Series. (2009). http://www.int-res.com/abstracts/meps/v389/p71-84/ (accessed February 23, 2014).