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Author Topic: Harbor Porpoise  (Read 1406 times)

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Plane

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Harbor Porpoise
« on: November 11, 2015, 11:00:57 PM »
http://www.ggcetacean.org/harbor-porpoise.html


Harbor porpoises went missing in San Francisco decades ago.

Now they are back!

Where did they go?
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Xavier_Onassis

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Re: Harbor Porpoise
« Reply #1 on: November 12, 2015, 08:03:09 AM »
Probably to one or more other harbors.

Most likely, the previous population died out, or sensed a disagreeable change in the environment and left.

The new harbor seals are probably descendants of those who left.
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Plane

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Re: Harbor Porpoise
« Reply #2 on: November 12, 2015, 06:35:18 PM »
  I think it is a good sign, these creatures probably have a circuit of harbors that they visit, but San Francisco repelled them until recently.

    The Clean Water Act might be responsible.
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Xavier_Onassis

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Re: Harbor Porpoise
« Reply #3 on: November 12, 2015, 10:21:53 PM »
One possibility is that an ample number of things harbor seals like to eat returned. Perhaps some fish returned because what THEY eat multiplied, as you say, because of cleaner water or the vanishing of pollutants.
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Plane

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Re: Harbor Porpoise
« Reply #4 on: November 13, 2015, 08:22:11 PM »
  Yes .

  The Clean water act of 1972 seems to be mostly a success.

http://www2.epa.gov/laws-regulations/summary-clean-water-act
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