American Robins

1
American Robins

• Robins are arriving earlier than before, often
  before the snow has even melted. They have to
  wait out the snow in order to eat and breed.
• In Colorado, robins are migrating from low to
  high elevations where they breed two weeks
  earlier than they did in the 1970s.
• (Tangley)

2
Mexican Jays

• In southern Arizona, the breeding season of
  Mexican Jays is as much as 10 days earlier now
  than in the 1970s.
• The change correlates with higher spring
  temperatures, which rose nearly 4.5? F.
• (Tangley)

3
Red-Winged Blackbirds

• Red-winged blackbirds are arriving at breeding
  grounds in Michigan nearly 20 days earlier than
  the 1960s.
• (Tangley)

4
Prothonotary Warblers

• These birds have been returning to breeding
  grounds in Virginia from South America and the
  Caribbean a day earlier for the past 20 years.
• (Tangley)

5
Loggerhead Sea Turtles

• Loggerhead sea turtles are coming ashore to lay
  their eggs about 10 days earlier than 1989.
• During this same time period, temperatures have
  increased by 1.5 ? F.
• Warmer temperatures are also affecting the sex of
  sea turtles because the gender of these reptiles
  is determined by sand temperature.
• (Tangley)

6
Red Squirrels

• Red squirrels are now bearing young about 18 days
  sooner
• This makes it the first known mammal to be
  evolving its phenology in response to global
  warming
• (Tangley)

7
Oaks

• Oaks are leafing out eight days earlier for every
  degree Celsius increase in temperature
• (Jensen)

8
Ash

• Ash trees are only leafing half as fast as the
  oaks
• (Jensen)
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