Killer whale predation on sea otters: how predation can cause major

Comments

Transcription

Killer whale predation on sea otters: how predation can cause major
Killer whale predation on
sea otters: how predation
can cause major changes
in an ecosystem
Special thanks to Dr. James Estes for
the images and figures
Location of the ecosystem – Aleutian
Islands, Alaska
Estimated Population Size
Change in sea otter populations
around the Aleutian Islands
100000
80000
60000
40000
20000
0
1900
1920
1940
1960
Year
1980
2000
2020
WHY?
Killer whale prey in the Aleutians
Great
Whales
Harbor
Seals
Steller Sea
Lions
Sea
Otters
1.0
Proportion of maximum
0.8
0.6
0.4
0.2
0.0
1950
1960
1970
1980
Year
1990
2000
Images from Estes et al. 1998
Images from Estes et al. 1998
Your turn!
Make a hypothesis about
what is going to happen
if the sea otters continue
to decline or even
disappear.

Similar documents