- [Woman Narration] The
California Channel Islands
are a series of eight islands
off the coast of Los Angeles
and Santa Barbara.
These islands have really
unique flora and fauna,
including the island fox.
The story of the California island fox
is a story of a recovering
endangered species,
but also an entire ecosystem.
(piano music)
(upbeat rock music)
- Here we are in the Channel Islands.
So close to LA yet a
completely different world.
- It is, it's a very special ecosystem,
and there are very unusual animals here.
How does archeology help you
conserve an area like this?
- Well archeology really
allows us to look back in time
and see what the environment
looked like 100 years ago
when there was historic
ranching on the island,
or 1,000 years ago when there were large
Native American villages on the island.
You look here, you see
an archeological midden
which is a deposit of their
wastes that they left behind.
Island foxes have been recovered
from over 50 different sites.
- [Jacques] So what kind
of things do they find
in the middens?
- So from Middens we have
shellfish, bones like these,
that we can extract DNA from
and learn about the past
environment as well as
what genetic diversity
might have looked like in the past.
(peaceful acoustic guitar music)
- What's the oldest island
fox that you've found?
- So the oldest island fox
has been radiocarbon dated
to about 7,300 years old.
Here we actually have the second
oldest island fox specimen
that is about 7,000 years ago.
We've sampled this for radiocarbon dating,
but also genetic analysis
and isotopic analysis.
- How does the process work?
- We take a small sample
like you see here,
a small little notch from a bone,
and we can extract DNA,
we can run isotopes,
we can look at trace element analysis,
all sorts of different methodologies.
- I measure the skulls
so that I can compare
the island fox in the archeological record
against the present day
samples with morphology.
Fast forward 35 years and
we have new technology now.
Courtney's gone back and
she's using new technology
to visit some of those same specimens
that I've pulled out of bags
and identified from sites.
It's caused us to completely
rethink our collections
and the value of the
collections and how we assemble
our collections.
- We know that island
foxes probably diverged
from their mainland
relative from between 9,000
and 7,000 years ago, which
is really interesting,
and it supports what
Paul had found earlier
with his morphological data that suggested
the northern California, Oregon foxes
are more morphologically
similar to island foxes.
But regardless of how they
got to the northern islands
originally, the fact was
that they were probably moved
by ancient peoples from
the northern island group
to the southern island group.
- You can find island fox bone pieces
or parts of island fox
that have been recovered
out of human burials.
And then you can find ceremonial burials
of whole island fox carcasses.
All of those speak to the
fact that Native Americans
were looking at island foxes
in a very different way.
They obviously revered them,
and they were important
to the Native American community.
- How does the fox's diet
change during the year?
- By looking at the scat that I found
that island foxes fed very intensively
in the late fall and
early winter on deer mice.
And then during the winter
we had a real increase
in the amount of beetles
that they were eating.
And then by the summer and
fall they transitioned into
feeding really intensively
on grasshoppers.
- Now we can do scat
analysis with metagenomics.
We can just sequence it and identify
what foxes were eating seasonally.
- A much cleaner and easier
way to do a study on diet
than I did.
- What was the impact of
ranches on population sizes
of these foxes?
- Grazing activity had a dramatic effect
on the terrestrial habitats.
Other animals like cats and
dogs may have been vectors
for introducing disease into
the island fox populations
resulting in dramatic
declines in populations
of the island fox.
- Just how small was the
population at that stage?
- On an island like San
Migeul island which went from
about 450 foxes down to
less than 15 animals.
(drumming music)
Bald eagles were a dominant
apex avian predator
on all of the Channel Islands.
They fed on primarily marine resources.
DDTs introduced into the environment,
it gets into the food chains
and causes egg shell thinning.
Bald eagle populations
disappeared by the early 1960's
from every single island.
That niche opened up and golden eagles
will find the islands.
At home they have these big things
that look like jackrabbits, and
they started to hammer them.
- What's the first step
to turn things around?
- It required the removal of
the introduced grazing animals
from the islands.
You have to get them off
because they were sustaining
golden eagles.
And you had to reintroduce
that apex avian predator,
the bald eagle, back
onto the Channel Islands
to fill that niche.
Fast forward 12 years
from start to finish,
the island fox was taken off
the endangered species list
in 2016.
- What was the effect of
restoring the island foxes?
- We're seeing an increase
in the available fresh water
in streams and seeps occurring in areas
where they've never been recorded before
because the vegetation
is now capturing fog
throughout the year and
you're having less runoff
and less erosion.
Those changes in habitat
have led to this growth
in populations of other endemic species.
So the island gopher snake
would be a good example.
Island scrub jays, their
habitat is slowly recovering.
If you want to recover the
species you have to recover
the system that it lives in
to make itself sustainable
over the long term.
And so by recovering the system
you allow the sustainability
of the species.
- It's an amazing story because
this little charismatic guy
here is changing the
whole ecosystem, right?
Restoring and working
to protect this species
is really transforming
an entire community.
(upbeat rock music)
- I was surprised to learn
how beneficial the impact
of island foxes is on the whole ecosystem.
- And who genomics can be
used to ensure the future
and health of the population.
