like to start tonight by something completely different
ninety percent of the living space on the planet is in the open ocean and it's where life the title of
our seminar tonight it's where life began and it's a lively and a lovely place but we're rapidly changing the oceans with our
not only with our overfishing our irresponsible fishing our adding of pollutants like fertilizer from our crop
but also most recently with climate change and steve schneider i'm sure will be going into greater detail on this now as we continue to tinker with the oceans
more and more reports are predicting that the kinds of seas that we're creating will be conducive to low energy type of animals like jellyfish and bacteria and this might be the kind of seas we're headed for
now jellyfish are strangely hypnotic and beautiful and you'll see lots of gorgeous ones at the aquarium on friday but they sting like hell
and jelly fish sushi and sashimi is just not going to fill you up about one hundred grams of jelly fish equals
calories so it may be good for the waistline but it probably won 't keep you satiated for very long
and a sea that's just filled and teeming with jellyfish isn't very good for all the other creatures that live in the oceans that is unless you eat jellyfish
and this is this voracious predator launching a sneak attack on this poor little unsuspecting jellyfish there a by the wind sailor and that predator is the giant ocean sunfish the mola mola
whose primary prey are jellyfish this animal is in the guinness world book of records for being the world 's heaviest bony fish it reaches up to almost five thousand pounds
on a diet of jellyfish primarily and i think it's kind of a nice little cosmological convergence here that the mola mola it's common name is sunfish that
favorite food is the moon jelly so it's kind of nice the sun and the moon getting together this way even if one is eating the other now
you see sunfish this is where they get their common name they like to sunbathe can't blame them they just
lay out on the surface of the sea and most people think they're sick or lazy but that's a typicalbehavior they lie out and bask on the surface
their other name mola mola is it sounds hawaiian but it's actually latin for millstone and that's attributable to their roundish very bizarre cut off shape
it's as if as they were growing they just forgot the tail part and that's actually what drew me to the mola in the first place was this terribly bizarre shape
you know you look at sharks and they're streamlined and they're sleek and you look at tuna
just so
really kind of holds its cards a lot tighter than say a tuna
so i was just intrigued with what you know what is this animal 's story well as with anything in biology nothing really
sense except in the light of evolution the mola 's no exception they appeared shortly after the dinosaurs disappeared sixty five million years ago at a time when whales still had legs and they come
from a rebellious little puffer fish factionoblige me a little kipling esque storytelling here of course evolution is somewhat random and you know
about fifty five million years ago there was this rebellious little puffer fictionfaction that said oh the heck with the coral reefs we're going to head to the high seas
and lots of generations lots of tweaking and torquing and we turn our puffer into the mola you know if you give mother nature enough time that is what she will produce
they look kind of prehistoric and unfinished abridged perhaps but
of the most evolutionarily derived fish in the sea right up there with flat fish they're every single thing about
fish has been changed and in terms of fishes fishes appeared five hundred million years ago and they're pretty modern just fifty million years ago
so interestingly they give away their ancestry as they develop they start as little eggs
and they're in the guinness world book of records again for having the most number of eggs of any vertebrate on the planet a single four foot female had
three hundred million eggs can carry three hundred million eggs in her ovaries imagine and they get to be over ten feet long imagine what a ten foot one
and from that little egg they pass through this spiky little porcupine fish stage reminiscent of their ancestry and develop this is their little adolescent stage they school as
and become behemoth loners as adults that's a little diver up there in the corner
they're in the guinness world book of records again for being the vertebrate growth champion of the world from their little hatching size of their egg into their little larval stage
till they reach adulthood they put on six hundred million times an increase in weight six hundred million now imagine if you gave birth
to a little baby and you had to
thing that would mean that your child you would expect it to gain the weight of six titanics
now i don't know how you'd feed a child like that but we don't know how fast
the molas grow in the wild but captive growth studies at the monterey bay aquarium one of the first places to have them in captivity
they had one that gained eight hundred lbs in fourteen months i said now that's a true american
used to be salvation for fishes but it's suicide for fishes now but unfortunately molas even though they don't school they still get caught in nets as by catch
if we're going to save the world from total jellyfish domination then we've got to figure out what the jellyfish predators how they live their lives like the mola
and unfortunately they make up a large portion of the california by catch up to twenty six percent of the drift net and in the mediterranean in
and how do you do that how do you do that with an animal very few places in the world this is an open ocean creature it knows no boundaries it doesn't go to land
how do you get insight how do you seduce an open ocean creature like that to spill its secrets
that little tag can record temperature depth and light intensity which is correlated with time and from that we can get
pre programmed time float to the surface upload all that data that whole travelogue to satellite which relays it directly to our computers
so the great thing about the mola is that when we put the tag on them if you look up here that's streaming off that's right where we put the tag
and it just so happens that's a parasitehanging off the mola molas are infamous for carrying tons of parasites they're just parasite hotels even their parasites have parasites
i think donne wrote a poem about that but they have forty genera of parasites and so we figured just one more parasite won 't be too much of a problem and they happen to be a very good vehicle for carrying oceanographic equipment
they don't seem to mind so far so what are we trying to find out we're focusing on the pacific we're tagging on the california coast and we're tagging over in taiwan and japan
and we're interested in how these animals are using the currents using temperature using the open ocean to live their lives
we'd love to tag in monterey monterey is one of the few places in the world where molas come in large numbers not this time of year it's more around october and we'd love to tag here this is an aerial shot of monterey but unfortunately the molas here
into the ultimate frisbee mola style and then tosses them back and forth and i'm not exaggerating it is just and sometimes they don't eat them it's just spiteful and you know
coming in getting ripped to shreds so we head down south to san diego not so many california sea lions down there
and the molas there you can find them with a spotter plane very easily and they like to hang out under floating rafts of kelp and under those kelps
this is why the molas come there because it's spa time for the molas there as soon as they get under those rafts of kelp
the exfoliating cleaner fish come and they come and give the molas you can see they strike this funny little position that says i 'm not threatening but i need a massage
go in the back of their head
great place to go down south because the water 's warmer and
you truly can swim up to a mola they're very gentle and if you approach them right you can give them a scratch and they enjoy it
so we've also tagged one part of the pacific we've gone over to another part of the pacific and we've tagged in taiwan
and we tagged in japan and over in these places the molas are caught in set nets that line these countries and they're not thrown back as by catch they're eaten we were served a nine course meal of mola after we tagged
well not the one we tagged
and everything from the kidney to the testes to the back bone to the fin muscle to i think that as pretty much the whole fish is
so the
part of tagging now is after you put that tag on you have to wait months and
i'm going to show you our latest dataset and it hasn't been published so it's totally privy information just for ted
and in showing you this you know when we're looking at this data we're thinking oh do these animals do they cross the equator do they go from one side of the pacific to the other and we found that they kind of are homebodies
not big migrators this is their track we deployed the tag off of tokyo and the mola in one month kind of got into the kuroshio current off of japan and foraged there
months went up you know off of the north part of japan and that's kind of their home range now that's important though because if there's a lot of fishing pressure
that population doesn't get replenished so that's a very important piece of data but also what's important is that
not slacker lazy fish they're super industrious and this is a day in the life of a mola and if we
down and as the sun gets brighter they go a little deeper little deeper they plumb the depths down to six hundred meters in temperatures to one degree centigrade
and this is why you see them on the surface it's so cold down there they've got to come up warm get that solar power and then plunge back into the depths and go up and down and up and down and they're hitting a layer down there it's called the deep scattering layer which a whole
variety of food 's in that layer so rather than just being some sunbathing slacker they're really very industrious fish that dance this wild dance between the surface and the bottom and through temperature
we see the same pattern now with these tags we're seeing a similar pattern for swordfishes manta rays tunas a real three dimensional play
of a much larger program called the census of marine life where they're going to be tagging all over the world and the mola 's going to enter into that and what's exciting you all travel and you know the best thing about traveling is to be able to find the locals
and to find the great places by getting the local knowledge well now with the census of marine life we'll be able to sidle up to all the locals and explore ninety percent of our living space
with local knowledge it's never it's really never been a more exciting or a vital time to be a biologist
and so i just
figured i'd have the questions answered and i'd be able to thank my funders like national geographic and lindbergh but people would write into the site with all sorts of all sorts of
everyone had a shared a shared love and an interest in the oceans i was getting reports from catholic nuns
jewish rabbis muslims christians everybody writing in united by their love of life
and to me that i don't think i could say it any better than the immortal bard himself one touch of nature makes the whole world
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