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" /> | |||
*Territorial Grazers-site-attached fishes that actively defend their territories against other herbivores | |||
*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<ref name="Corn" /> | |||
==Feeding Habits of Herbivore Fish/How Food is Digested<ref name="Corn" />== | ==Feeding Habits of Herbivore Fish/How Food is Digested<ref name="Corn" />== | ||
*Focus on enriched macrophytes | |||
*Shallower reefs have more herbivorous fishes and increased grazing rates | |||
*Some prey directly on Corals (parrotfish)<ref name="Burk" /> | |||
*Feed on red, green, and brown macro algae<ref name="Corn" /> | |||
*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== | ==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<ref name="Loic" /> | |||
*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<ref name="Burk" /> | |||
*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<ref name="Corn" /> | |||
**Caused collapse of Caribbean reefs in this area | |||
**Macroalgae became dominant | |||
**Decrease in diversity | |||
References | References | ||
Revision as of 23:01, 5 March 2014
Herbivory
Three Types of Herbivorous Fishes [1]
- Reef fishes that are herbivores are typically invertebrates [2]
- Territorial Grazers-site-attached fishes that actively defend their territories against other herbivores
- 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).