Human Ecology Pagano



I. Coral Reefs
  A. Animals and function within ecosystem of low latitudes ( high rate of growth)

    1. Zooxanthellae are immobile dinoflagellates and numbers of individuals within corals

        can reach 30,000 per cubic millimetre.

            a. much of food for many coral species is provided by these microscopic green algae.

            b. it lives within the polyp (reef building corals-colonies of tiny individual animals)-

                it provides protection, and waste products for nutrients.

            c. zooxanthellae provides food and oxygen for the living coral by recycling waste

                products and carrying out photosynthesis. It provides up to 90% of polyp's

                nutrient's requirements and a large proportion of its biomass.

            d. when coral polyps lose there partners -zooxanthellae, they leave large areas of

                white behind.

 

II. Coral Reefs animals in the Indo-Pacific

      A. There is about 700 known species living here.

           1. The underlying little animal that everything depends on at a low level

                     on the food chain is the Calcareous red algae.

                a. This red algae holds together the major species diversity of this community-

                      considered one of the highest of all biological habitats in the sea.

 

 

 

Tertiary consumers:         Eels, Octopuses, and Barracudas

 

Secondary consumers:      Sea Urchins, Sea Anemones, Crustaceans, Starfish Gastropods,

                                           Parrotfish, Butterfly Fishes, Porcupines fishes

 

Primary consumers:          Corals, Clams, Sea urchins, Crustaceans, Brittle-stars, Gastropods,

                                           Grazing fishes.

 

Primary consumers:           Zooanthellae / Calcareous Algae / Algal Mats / Phytoplankton

                                           Microscopic Epiphytes

 

 

         It is important that humans don't upset this process of the food chain, by making it unbalanced.  An example of this is when Carnivorous invertebrates- which include certain polyclad worms, sea slugs, gastropod snails and starfish, such as the voracious crown-of thorns Starfish Acanthaster Planci.  This starfish goes though cyclic population explosions with high numbers of these critters destroying whole areas of coral reef, leaving them white.  When the population declines naturally by lack of food, and by disease, this allows the reef to slowly recover.  So when humans interfere with this process, we get in the way of allowing the reefs to recover by themselves. They already have these Carnivorous creatures eating at them they don't need humans on their food chain.   Another example would be messing with a fish eating- overeating diet.  (Overpopulation) The most common creatures humans eat are fish.  The reef fishes are the dominant vertebrates among the coral reef communities.  Fishes are of 70% carnivorous, 20% herbivorous, and 10% omnivorous species. So these large numbers of animal species leads to intense competition for food and living space.  The reef needs
these fish to keep populations of other fish and the reef food chain imbalance.