Download DESIGN AN ECOSYSTEM

* LAB ACTIVITY – DESIGNING AN ECOSYSTEM *
I. Introduction
In today's activity, you are to create several species in a unique ecosystem. You will create a food web
describing the interaction of the organisms in your ecosystem. You will then prepare an Environmental
Impact Report (EIR) describing the expected effects of an environmental disturbance (e.g. flood,
paving over the ecosystem to make a Wal-Mart parking lot, introduction of a foreign species, etc.).
- Keep it simple. You won't have forever to do this activity.
- Look ahead. Consider the conditions associated with species endangerment while you plan
your ecosystem. That way your EIR will be more interesting.
- Use your textbook and other sources to understand new terms and for ideas.
II. Materials
Poster paper (or other format), color markers (or other accessories), notebook paper, pen/pencil, ideas
III. Procedure
A. Your mission is to design and artistically depict an ecosystem.
B. Use the following criteria:
1. Location: Your ecosystem must be located in a specific biome. (Each group’s ecosystem must be
located in a different biome.)
2. Biotic factors:
a. Include at least one species of each of these: (min-6 species total; max-10 species total)
i. Producers (autotrophs)
ii. Primary consumers (heterotrophs)
iii. Secondary and higher level consumers (heterotrophs)
iv. Decomposers
C. Now that you have created a beautiful ecosystem, add a disturbance. Your disturbance may be
spontaneous or man-made; intentional or unintentional, or a combination of these.
Some possibilities include (but you are definitely not limited to):
- Climate change: warming, cooling, change in water availability.
- Direct human interference: hunting/harvesting, land clearing, pesticides/herbicides,
introduction of a foreign species, etc...
D. Identify the effect of the disturbance on the species in your ecosystem. Use the list below to help
you make the following declarations:
i. Extinct: Species which are completely decimated.
ii. Endangered: Species which are in imminent danger of extinction.
iii. Threatened: Species which are at significant risk of becoming endangered but are not in
immediate danger of becoming extinct.
iv. No expected change: Species with moderate to large populations, whose numbers are
expected to remain stable.
iv. Increased: Species whose populations increase. They may be potential pests.
E. Prepare your EIR describing what happens to each species. The EIR should also state why you are
making your predictions. Include ideas for mitigation (lessening) of the environmental
impact. Be prepared to share your results with the rest of the class.
Conditions Associated with Species Endangerment
i. Limited Range : Species is found in only a small, specific area.
ii. Small Population or Rarity: Species is rare within its range. High level consumers are
usually rare. Other species may also have small populations.
iii. High Specificity: Species has very specific requirements for: food (e.g. Pandas only eat
bamboo; animals which eat only one type of food, or a few specific foods, are prone to
extinction if the food supply disappears.); reproduction (e.g. Spotted Owls only nest in
old coniferous tree hollows, rabbit fleas use female rabbit reproductive hormones
and don't make their own); habitat (e.g. there are fungi which are found only in gopher
tortoise burrows); etc...
iv. High Sensitivity: Species is extremely vulnerable to environmental disturbances.
Examples include: Birds are very sensitive to DDT and related pesticides which cause
thinning of their eggshells. Compare birds with cockroaches, which are not very
sensitive. Some plants have very specific requirements for light; too much or too little
sunshine will kill them.
v. Low Fecundity: Species produces few offspring. Note: species which care for their young
either before birth (long pregnancy) and/or afterwards have fewer offspring than those
who do not.
vi. High Human Value: Species has characteristics that make it valuable to humans. Many
animals have been hunted to endangerment, or even extinction, for their beautiful
plumage or fur. Wild plants and fungi may also be over-harvested if they are
particularly tasty or contain useful medicine.
Report (2 lab grades) – what you will be graded on
Lab grade 1:
Poster (or project)
Food Web (8.5” x 11” sheet of paper)
Lab grade 2:
Environmental Impact Report (1-2 pgs – typed, double space)
Due Date: ________________________________________
SAMPLE EIR
ENVIRONMENTAL CHANGE:
A gravid (pregnant) Lily Weevil is inadvertently introduced into the valley. The Lily Weevil eats immature Norse Sea Lily
fruit. Worse yet are its reproductive habits. It parasitizes hymenopterans by stinging them into paralysis and laying a single
egg in the abdomen of each insect. The Weevil larva then feeds upon its host from the inside out! Needless to say, this is an
experience which a Mead Bee does not survive.
IMPACT ON SPECIES:
Extinct :
At this time it is not possible to tell whether any of these organisms would actually go extinct. However endangerment, by
definition, means that a species might go extinct in the near future.
Endangered:
Mead Bee: Bees are being massacred by the Lily Weevil, a newly introduced species.
Yeast Beast: Yeast Beasts are totally dependent on Mead Bees. If the Mead Bee dies out, so will the Yeast Beast.
Norse Sea Lily: Not only do Weevils eat their fruit before their seeds have formed, they also parasitize the Lily's only
pollinator. The Lily may not be able to reproduce in the presence of the Weevil. Finally, human predation may also
contribute to their demise.
Threatened:
MoVal Viking: The Vikings could loose three important food sources: Lilies, Go Fish, and mead. Fortunately, Vikings
have other food sources available to them.
Go Fish: Go Fish would loose a major food source. Also Vikings may predate more heavily upon the fish since the Vikings
no longer have Lilies and mead.
No Change :
Ship Worm: One way or the other, there will be plenty of dead for the Ship Worm to eat.
Increased:
Lily Weevil: Since the valley is full of food (Lilies) and reproductive opportunities (Bees), Weevils may increase in
population. Contributing to their increase is the lack of natural predators such as Leaping Lizards which eat them.
MITIGATION:
Prevent entry of the Lily Weevil:
Prevent, or at least delay entry, of this dreaded pest. Recommended practices include:
Do not import, or import only after quarantine, agricultural products, such as aquarium and pond plants, which may be
infested with the Lily Weevil. While this idea is sound, it may be difficult to carry out. Backyard pond enthusiasts may not
understand the need for not smuggling various exotic plants which they would like to grow at home.
Population control for the Lily Weevil:
If entry cannot be prevented, methods of limiting Weevil population must be explored. For example:
Pesticides:
Some pesticides kill Lily Weevil effectively; but others are no longer effective since the Lily Weevil has evolved resistance
to them. Also, the same pesticides that kill Weevils, kills Mead Bees. This solution has only limited viability.
Introduction of Weevil predator:
A population of Leaping Lizards could be introduced to the valley. Lizards would keep the Weevil population low. They
would not completely eradicate the Weevil. Prior to their introduction, extensive research is recommended as it is not
known what other organisms would be effected by the Lizards. For example: would Leaping Lizards eat Mead Bees; out
compete the local Friendly Frog for insect food; or in some other way become a pest?