welcome to k passionate
i'm your host kp a marine biologist with over a decades worth of experience
working with marine mammals like sea otters
in a few weeks i'm going to be hosting a charity event for the alaka alliance
a non-profit organization looking to restore sea otters off the oregon coast
and thereby make oregon's marine and coastal ecosystem more diverse robust and resilient
so in preparation for that event which will take place on october 16th i thought we should take a
deeper dive into the importance of sea otters and the environment that they protect but before we do
a quick reminder to like and subscribe head down to the descriptions below if you want
to learn more about the alaka alliance and ways that you can help support the channel
previously we talked about how sea otters were hunted to near extinction
during the fur trade they were then protected in 1911 by the fur seal treaty
thanks to conservation efforts like the alaka alliance sea otters have regained
two-thirds of their historic range in case you missed it you can learn more
about the history of sea otters right up here however there is
one key moment that i didn't have time to cover in that video and it happened in 1971
and that's when a marine ecologist from the university of california santa cruz named james
estes made an amazing discovery while diving off the aleutian islands in alaska
he found that ecosystems where sea otters had disappeared had become underwater deserts
and these ecosystems used to be the kelp forests
kelp forests are one of the most dynamic and productive ecosystems
in the world they support more biodiversity and sequester more carbon than a similar sized
redwood grove in fact kelp forests are capable of storing between 4.4 and 8.7 million tons of carbon
that's more carbon than that emitted from a million passenger cars for an entire year
and when that kelp dies and sinks that sequestered carbon can be
harbored on the sea floor for thousands if not millions of years
but that same marine ecologist that i mentioned james estes who discovered the underwater deserts
also discovered that in areas where sea otters had returned
the kelp forests had not only grown back but were flourishing growing at a rate of up to two
feet a day and it had everything to do with the sea otter's insatiable appetite
dude finish up your pockets next
pocket they are the only marine mammal without a thick layer of blubber
relying instead on a very dense fur coat and an incredibly impressive metabolism
few other animals eat as much in relation to their body weight
and their food of choice is usually sea urchins damn it oh he's moving on me you got it which are
a phylum of marine animals usually identifiable by their five-point radial symmetry that
five-pointed symmetry is easily identifiable in animals like sand dollars or sea stars
but to find it on a sea urchin you have to look a little deeper
this is the sea urchin's jaws it consists of five arrow-shaped plates each with hard teeth
pointing towards the center of the mouth and it was first described by the legendary greek scholar
aristotle in his history of animals and is affectionately termed aristotle's lantern
just like sea otters sea urchins are voracious eaters and they use
that aristotle's lantern those sharp teeth
to mouth through the kelp forest usually at the very base where the kelp is attached to the ground
the rest of the kelp then rises to the ocean surface
is washed ashore and all that stored carbon returns to the atmosphere
now one might think that these urchin barrens would be unsustainable to the sea urchins
if they simply eat all the kelp then the urchins should die off right when a sea urchin runs out
of food it simply becomes dormant these dormant sea urchins have been described by researchers as
sea urchin zombies because they can survive that way for around 50 years
it is estimated that about 95 of kelp forests have been lost to these sea urchins and some
scientists believe that the only way to bring them back is to bring back the sea otters
it's something called a trophic cascade
trophic cascades are powerful interactions that can control the entire ecosystem and they occur
when predators limit the density of prey or more importantly change the behavior of the
prey a well-documented example is what happened when the wolves were reintroduced to yellowstone
the presence of wolves changed the feeding behavior of deer and elk
which allowed plant species like willow trees to regenerate
which the beavers used to build dams these beaver dams evened out the seasonal runoff
stored water for recharging the water table and provided cold shaded habitat for fish
these trees and fish provided shelter and food for birds like eagles and migratory songbirds
a similar thing happens when sea otters are reintroduced to their historic habitats
they significantly reduce the sea urchin population which allows the kelp to regenerate
which provides shelter for fish shrimp and krill and when the fish return so do the seals
the sea lions and the dolphins the entire ecosystem rejuvenates stabilizes
and becomes an important carbon sink for atmospheric carbon dioxide
many researchers believe this could be key in helping combat climate change
the question then becomes how do we reintroduce sea otters we'll answer that in next week's
deeper dive be sure to like subscribe and drop a comment down below if you have any questions
you can also head over to my twitch channel and ask me live there's a link to that and more
information about our charity event for the alaka alliance down in the descriptions below cheers
you