The list of organisms directly involved in this case have been narrowed to four groups. Provided for you are some general information about the organisms' eating habits, size, and other notes. Create a diagram showing the relationships between the organisms.

Fish Guano birds Humans Plankton
  • Anchovy
  • Plankton-eating fish
  • Peruvian pelican
  • Peruvian booby
  • Guanay cormorant
  • Peruvians

 
  • Phytoplankton
  • Zooplankton

 
FISH
Anchovy
  • Engraulis ringens
  • DIET: zooplankton & phytoplankton
  • DISTRIBUTION: Peruvian & Chilean coasts
  • PREDATORS: Large fish, guano birds, marine mammals, humans
  • NOTE: a.k.a. anchoveta, anchoa; juvenile anchovy = peladilla

(sealevel2.jpl.nasa.gov/jr_oceanographer/images/o-carr-anchovy.jpg; Jordan, 1980).

Other plankton-eating fish

  • Brevortia m. chilcae (machete) and Sardinops sagax (sardine)
  • DIET: zookplankton & phytoplankton
  • DISTRIBUTION:
  • PREDATORS:
  • NOTE: These pelagic schooling fish are at the same trophic level as anchovies. They can be considered predators of the anchoveta because their zooplankton diet also include anchovy eggs and larvae.

(www.neptunetrading.com/pacificsardines.htm; Jordan, 1980)
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Guano birds

  • Peruvian pelican (Pelicanus thagus), Peruvian booby (Sula variegata), and Guanay cormorant (Phalacrocorax bougainvillii).
  • DIET: anchovy, squid, sculpin
  • DISTRIBUTION: Peruvian coast
  • PREDATORS:
  • NOTE: Guano is a natural fertilizer made from bird droppings, and was a prized commodity during the 19th century. Anchovy accounts for >90% of the cormorant's diet, and >80% of the pelican and booby's diet.

How are these birds a major concern to the anchovy fishing industry?

All guano bird photos taken by Nick Lowton, 2003 (http://www.niltava42.freeserve.co.uk/peru.htm)
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Humans

  • POPULATION: 27, 949, 639 (July 2002 est.)
  • ETHNIC GROUPS : Amerindian 45%, mestizo (mixed Amerindian and white) 37%, White 15%, Black, Japanese, Chinese, and other 3%
  • RELIGION: Roman Catholic 90%
  • LANGUAGES: Spanish (official), Quechua (official), Aymara
  • LITERACY (definition: age 15 and over can read and write): total population: 88.3%; male: 94.5% female: 83% (1995 est.)

(www.cia.gov/cia/publications/factbook/geos/pe.html and sealevel2.jpl.nasa.gov/jr_oceanographer/images/o-carr-peru.jpg)

Notice that the anchovy is not harvested for direct human consumption, and yet it is economically and nutritionally important to us.

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PLANKTON
Zooplankton Phytoplankton
  • Name refers to free-floating heterotrophic organisms. These include microorganisms such as foraminifera, radiolaria, copepods, euphausiids, and larval stages of larger marine organisms
  • DIET: phytoplankton, other zooplankton
  • DISTRIBUTION: Worldwide
  • PREDATORS: filter feeding organisms
  • NOTE: Anchovies spend the first two steps of their life cycle as zooplankton, i.e. eggs & larvae.

(www.niwa.cri.nz/)
  • Name refers to free-floating, microscopic plants such as diatoms, dinoflagellates, cyanobacteria, and coccolithophorids.
  • DIET: Require supply of nitrogen and phosphorous in order to carry out photosynthesis.
  • DISTRIBUTION: Worldwide
  • PREDATORS: zooplankton, filter feeding organisms
  • NOTE: Primary producers in the ocean. Their presence influence abundance of other marine organisms, but they are limited by N & P availability.

(www.microbe.org and www.indiana.edu/~diatom/diatom.html)

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This web site was created by Lynn Tran at the North Carolina State University, Department of Mathematics, Science, and Technology Education on 7/12/03. Faculty advisor Dr. David Eggleston, NCSU, Department of Marine, Earth, & Atmospheric Sciences. Last updated December 29, 2003 .