Top Carnivore - Friend or Foe Review where we are in the course Link to Wednesday lecture Exponential vs. linear growth Explore: Top Carnivore: Friend or Foe Food chains Food Webs Bioaccumulation Competitor or friend of conservation Readings: Yellowstone Story Lecture on Conservation Concept of Shrinking Expectations

Course Context Very simple diagram Earth Systems Biosphere Hydrosphere Lithosphere Atmosphere Air Resources Water Resources Ecosystem Resources e.g., forests Other (Non- Renewable) Resources e.g., oil I. = P.A.T. Population (# people) Affluence (GDP/person) Technology (tons CO 2 /GDP)

Yoram’s Final Two Statements “I am a technology realist” “That is why I think a carbon tax is needed” Vehicle fuel efficiency is target of proposed tax Cars blamed for global warming; Eyman fires back By BRIAN SLODYSKO P-I REPORTER February 7, 2008 OLYMPIA -- Seattle Mayor Greg Nickels and Sen. Ed Murray, D-Seattle, want car owners to warm to the inconvenient truth of cutting vehicle emissions.

Pick an option for your summer job (50 days) 1.$0.01, $0.02, $0.04, $0.08, etc. 2.$100.00, $100.00, $100.00, $ Answer Now! 10

Day 20: Penny person = $10,486 ($5243) Day 50: trillion dollars Outcome Day 20: $100 person = $2000 ($100)

1968: Garrett Hardin freaks out Tom Hinckley 1968 Not freaking out

Linear vs. exponential growth (or decay) Exponential: N t = N o e kt N o - initial quantity t - time N t - quantity after time t o k - constant e - exponential function (e is the base of the natural log) Linear: N t = N 0 *t

Growth/Time Linear Exponential Illustration/Reference Population Growth: Has been exponential Population Growth is a function of a number of parameters With each time interval: Linear: increases by 2 (+ 2) Exponential: doubles (*2)

The parable of the lily pond If lilies growing in a pond double every day, and on the 100 th day they cover the whole pond, on what day do they cover half of the pond?

99 th day The parable of the lily pond: a test If lilies growing in a pond double every day, and on the 100 th day they cover the whole pond, on what day do they cover half of the pond?

Food Chains, Food Webs, Trophic Levels, Bioaccumulation Obey 1st & 2nd laws of Thermodynamics –Energy cannot be created or destroyed; only its form can change. –Conversion of energy is inefficient Main source of energy is the sun. Role of biogeochemical cycles.

Trophic Pyramid Very simple diagram 10% rule Herbivores Omnivores Top Carnivores Detritus or Decomposition Chain Connections between levels: chain or web Compounds from Biogeochemical cycles Producers 1 - 5%

Food Web Example

Bioaccumulation As a consequence of energy flow through a food chain (i.e., you must eat a lot!), certain compounds can accumulate. Examples –Fat soluble compounds DDT Tetra-ethyl lead Methyl mercury Dioxin PCBs

Top Carnivores: Friend or Foe “Killing sea lions will not save Columbia River salmon” By John Balzar Special to The Times February 7, 2008 Foe Friend Reading for Today Wolves in Yellowstone & Cougars in Zion N Park Grizzly or wolf as an umbrella species

Foe Shared space Status Fear Competition Food Space Example with sea lions

Which of the following statements is false. 1.Wolves were extirpated in Beavers returned after wolves returned 3.Elk browsing increases aspens & willows 4.Rivers became incised with elk browsing 5.Wolves are carnivores & predators Answer Now! 10

Impact is a trophic cascade!

Visuals W.J. Ripple photographs, OSU

Impact is a trophic cascade!

Zion National Park, Utah

Summary: Top Carnivores Exponential vs. linear changes First and second laws of thermodynamics Energy from the sun Biogeochemical Cycles Food chains, webs, trophic cascades, bioaccumulation Foundation for Conservation Biology Fundamental changes in how we think!

Concept of Shrinking Expectations Current Condition or state Future Condition or state Historical Condition or state Russell Jim