Sharks are a Keystone Species
(b) Analyze changes in an ecosystem;
(c) Fluctuations in population size in an ecosystem
NETS-S Technology Standards Addressed
1. Facilitate and Inspire Student Learning and creativity
2. Design and Develop Digital-Age Learning Experience and Assessments
3. Model Digital-Age Work and Learning
4. Promote and Model Digital Citizenship and Responsibility
This lesson Plan is for a 2 Week Group Project that follows the study of The Oceans in their textbooks.
This research project will allow the students to explore the answer "What would happen if sharks disappeared", and requires the students to answer the following questions in their project:
What would happen to the oceans by the loss of the large sharks, as top predators in shaping ocean ecology?
When most people think of sharks they often think of terror, shark attacks, and blood. In reality, the odds of being attacked by a shark are very small. In the US, the odds of being attacked by a shark are approximately 1 in 6 million. You are more likely to get struck by lightening, die from falling down the stairs, or drown in your own bathtub. In the first part of this lesson, students will become aware of how rare shark attacks really are.
In the project part of this lesson, students will explore the importance of sharks in an ecosystem. Ecosystems are typically composed of a number of species and some of the species present in an ecosystem are very important for maintaining the structure of that ecosystem. For example, if one important species is removed from an ecosystem, the entire ecosystem can be disrupted. Such important species are often referred to as keystone species. A keystone species can be a top carnivore that keeps the size of prey populations in check, important plants that support insects that are prey for birds and bats, or any other organism that supports a number of other organisms in the ecosystem. If the population of a keystone species is removed or decreases, other species in that ecosystem will be affected and the species that are supported by the keystone species will disappear.
The protection of keystone species is essential for the maintenance of ecosystem health. Protecting a keystone species protects that keystone species and all of the other species that rely on that keystone species.
many aquatic ecosystems sharks are keystone species. In other words,
the removal or decline of sharks in an ecosystem will affect many other
organisms in that ecosystem. Tiger sharks provide a good example. Tiger
sharks will eat almost anything dead or alive, and they consume a large
number of sea turtles. Sea turtles consume large amounts of sea grass,
and if sharks did not eat sea turtles it is possible that the sea
turtles would overgraze the sea grass. If there were too many sea
turtles and the sea grass was overgrazed, many of the animals that rely
on the sea grass, such as fish, would disappear. If animals such as
fish disappeared, animals that eat fish, such as the bottlenose
dolphin, would also disappear. Thus, by simply removing one species,
the tiger shark, the entire ecosystem is affected and many of the
species will disappear from the ecosystem.
cover more than 70 percent of our planet yet they make up one of the
least explored regions on Earth. Through the Tagging of Pacific
Predators program (TOPP), scientists hope to both assess and explain
the migration routes, ecosystems and diversity of our oceans’ species.