Indicator and Keystone Species Important niche species Learning

Indicator and Keystone Species • Important niche species

Learning Goals • I know what an indicator and keystone species are • I know what TROPHIC CASCADE is and why it is a problem for ecosystems • I know what ecological engineers are

What’s a Niche?

Take a minute and write down your own definition of a niche…

What Are Indicator Species? • Indicator species serve as early warnings of damage to a community. • Birds and butterflies are migratory and are excellent indicators of the environment. They do not return to areas along their migratory routes where deforestation has occurred or where broad spectrum pesticides have been applied. • Amphibians are also a universal indicator of environmental degradation as they BREATH through their SKIN.

Why Are Amphibians Vanishing? • Appeared in the fossil record about 350 million years ago. • Frogs and toads have been around for 150 million years (indicates adaptability) • Last 20 years nearly 3, 000 species of frogs and toads have disappeared.

Reasons for Global Amphibian Declines • Global climate change (Costa Rican golden toads) • Dehydration weakens amphibians, susceptible to fatal diseases. • Introduction of non-native predatory fish into aquatic habitats. • Pollution (air, water, soil)– respire through skin. • Consume insects that take up pesticides (bioacumulation/biomagnification). • Eggs sensitive to increases in UV radiation – endocrine blockers) • Consumption of frog legs (delicacy). • Loss of habitat.

Effects of Pesticides

Effects of Climate Change

Indicator Species • As indicator species, amphibians may be sending us an important message about the health of the global environment. • They don’t need us, but we and other species need them. Golden toads – once prevalent in Costa Rica’s cloud forest have disappeared. https: //www. youtube. com/watch? v=1 b. Mwz p. DF 0 Sk

Indicator Species in Aurora

Why Should We Care About Indicator Species? • They give clues that the environmental health is deteriorating in parts of the world such as habitat loss and degradation, pollution, UV exposure, and climate change. • They provide ecological services (niche) in biological communities. ie. Amphibians eat more insects including mosquitoes than birds. They provide a food source for higher trophic levels. • Amphibians especially provide a storehouse of pharmaceutical products waiting to be discovered (economic goods and services).

What Are Keystone Species? • A keystone species holds a community together, when it disappears, so does the biological community. Elimination of a keystone species dramatically alters the structure and function of a community.

Why Should We Protect Keystone Species? • They play critical roles in the cross pollination of flowering plants (bees, hummingbirds, bats). • Top predator keystone species help regulate the population numbers of other species. • The loss of keystone species can lead to population crashes and extinctions of other species that depend on it for ecological services.

A Special Kind of Diversity • Keystone Species • https: //www. youtube. com/watch? v=N 2 Me mfw. GFu 4

E. O. Wilson • “The loss of a keystone species is like a drill accidentally striking a power line. It causes lights to go out all over”

Long video… let’s see if we have time • https: //www. youtube. com/watch? v=SAGE XDl. UHDE

Your turn to investigate a Keystone Species! • • • Sea Otter African Elephant Ochre Sea Star Grey Wolves Honey Bees • Great White Shark • Grizzly Bears • Pacific Salmon • Snow Geese • • • Group 1 Group 2 Group 3 Group 4 Group 5 Group 6 -

Ecology Picture of the Day