• Case study: peregrine falcons in Canada

Question 1

where are they found

Answer 1

• Falco peregrinus
  
  • Distributed globally, mainly in northern hemisphere
  • predators

Question 2

how was DDT initially viewed? what wasnt known?

Answer 2

○ DDT initially thought to be positive as it protected humans from many insect-borne diseases
Was considered nontoxic for humans - was not understood to have long term consequences

Question 3

how did ddt impact organisms

Answer 3

it was found to impact organisms through biomagnification as it does not degrade - amplifies as you move up the food chain

Question 4

how did ddt impact falcons

Answer 4

○ Eggshell thickness and egg weight over time - shells were thinner and brittle, and decreased in size
○ Eggshell thinning was greatest in populations with greatest decline - reduced recruitment due to DDT

Question 5

recovery efforts?

Answer 5

○ DDT use was banned, alternatives developed
○ Populations began to increase, particularly in the 2000s
○ Giving natural systems a change to rebound in key in conservation
○ Amount of DDT found in flacons trending downward

Question 6

currently?

Answer 6

○ However, DDT is not banned globally- still used in some areas bc of low cost
• Recently - 2017
○ Peregrine Falcon no longer declared a threatened species
○ Huge improvement