Browsing Tag: coral reef

    Bringing Fish Up from the Deep | Engineering Is
    Articles, Blog

    Bringing Fish Up from the Deep | Engineering Is

    October 15, 2019


    One of the most interesting parts of
    the ocean for me is this area that we call the twilight
    zone which is this narrowband of the ocean between about 200 and 500 feet the below the surface of the water. It’s
    mysterious It’s unknown. It’s sort of enchanting and
    captivating but also it’s an area where literally
    the light is like Twilight. This Twilight Zone
    is part of the coral reef, but it’s a part that is
    very understudied. About half of the fish are not known.
    Nobody goes down there because there’s a lot of technical difficulties associated going there. So
    a lot of the times those deep reefs are being destroyed even before we identify what’s down there. It wasn’t
    until really recent years that we’ve had sophisticated and reliable diving
    equipment that allowed people to actually go down
    there and come back. One of the most challenging aspects to
    this diving really is the pressure. The deeper you go in the ocean the
    more and more pressure is stacking up and that’s essentially just
    all that water that’s over your head pressing down on your body. One of the
    first things we recognize is that the fish that we wanted to bring up
    from the depths were subject to the same decompression issues that humans are. So
    most fish have swim bladders. It’s a little
    chamber filled with gas that keeps them neutrally buoyant. So, if they
    didn’t have a swim bladder because the fish, the tissues are heavier than water they would just
    sink. If you capture a fish at those depths and you just bring it to the surface
    that swim bladder is going to inflate – the gas expands
    inversely to the pressure. The swim bladder expands it pushes the
    stomach away, pushes the heart, the heart stops beating and then everything else collapses just
    because the swim bladder takes the space of everything. There’s an anti in there
    somewhere. There’s one there. from Hawaii. I started to hear
    about the idea of the Academy going down and
    exploring deep under the ocean with divers and
    possibly collecting fish down there. And since my job is to make sure that
    those fish come back healthy I thought about different ways that we could make sure that they could handle that
    pressure change. Is there a way that we can see all the fish up at pressure keep
    them at the pressure that they were collected at and bring them to the
    surface and slowly decompress them over a period of a few days so that we don’t have to have any of
    that trauma. What we wanted to do was take the pressure chamber underwater
    with us. We knew if we want to dive with it that it needed
    to be sturdy, yet sleek, yet light, yet all these things that
    sort of are design compromises. And it also needs to have corse be able
    to handle the immense amount of pressure that’s on it. The first sort of flash bulb over the head idea that we had was to use a water
    filter housing They’re used for home water filtration. It’s about two gallons. It’s enough space for fish to live in that space for about 24
    hours while we decompress them. And that’s a cheap off the shelf unit
    you can get one for about a hundred dollars. And then we just heavily modified it. This is
    the main pressure canister, the main pressure chamber. I mean it’s basically tinkering on a grand
    scale. I mean I played with Legos when I was a kid and this is like real adult legos right? Putting all
    these things together and seeing how they work and seeing how an idea that is brand new, that nobody’s ever
    done before. Seeing how it works in the real world is great. It’s a dream job. It’s a portable, submersible, decompression chamber. You just pull the
    velcro open and stick the fish in and seal the velcro. And then once we were done with the
    collecting, we make sure that we seal it all up tight, make sure it holds the pressure, and then we
    start our assent. They bring it up to the boat, and then we
    connect it to a water supply and our pressure generating pump. And that pushes water through the
    cannisters so that the fish start to get a water change. We keep it like that for next 24 hours
    while we slowly start to bleed off that pressure until it’s at surface pressure. We brought
    back you know probably a dozen or so species
    of fish from the twilight zone, including some really favorites of mine called
    ferry basslets. And they have great colors and they live in this unique
    social structures with harems of males and multiple
    females. It’s wonderful I come in, I check on them
    every day. I’m gonna try and find, you know, the fish that I collected at 300 feet and the Philippines. For me
    bringing back live animals and getting them on to the public floor is a direct way to connect with, you know,
    at least a million-and-a-half people who come to the Academy, and show them a living real thing. An
    authentic thing that came from deepest depths of
    the ocean. I think in order for people to really understand
    and want to conserve and protect life in these depths they have to have a direct connection with it.

    The secret lives of baby fish – Amy McDermott
    Articles, Blog

    The secret lives of baby fish – Amy McDermott

    October 9, 2019


    What you’re looking at
    isn’t some weird x-ray. It’s actually a baby yellow tang surgeonfish
    at two months old. And you thought your childhood
    was awkward. But here is the same fish as an adult, a beautiful inhabitant of the
    Indian and Pacific Oceans’ coral reefs and one of the most popular captive fish
    for salt water aquariums. Of the 27,000 known fish species,
    over a quarter live on coral reefs that make up less than 1%
    of the Earth’s surface. But prior to settling down in this
    diverse tropical environment, baby coral reef fish face the difficult
    process of growing up on their own, undergoing drastic changes,
    and the journey of a lifetime before they find that reef to call home. The life cycle for most of these fish begins when their parents spew
    sperm and eggs into the water column. This can happen daily, seasonally,
    or yearly depending on the species, generally following lunar or
    seasonal tidal patterns. Left to their fate, the fertilized eggs
    drift with the currents, and millions of baby larvae
    hatch into the world. When they first emerge,
    the larvae are tiny and vulnerable. Some don’t even have gills yet
    and must absorb oxygen directly from the water
    through their tissue-thin skin. They may float in the water column
    anywhere from minutes to months, sometimes drifting thousands of miles
    across vast oceans, far from the reefs where they were born. Along the way, they must
    successfully avoid predators, obtain food, and ride the right currents
    to find their way to a suitable adult habitat, which might as well be a needle
    in vast haystack of ocean. So, how did they accomplish this feat? Until recently, marine biologists thought of
    larval fish as largely passive drifters, dispersed by ocean currents
    to distant locales. But in the last 20 years,
    new research has suggested that larvae may not be
    as helpless as they seem, and are capable of taking
    their fate in their own fins to maximize their chances of survival. The larvae of many species are
    unexpectedly strong swimmers, and can move vertically in the water column
    to place themselves in different water masses and preferentially ride certain currents. These fish may be choosing the best routes
    to their eventual homes. When searching for these homes, evidence suggests that larvae navigate
    via a complex suite of sensory systems, detecting both sound and smell. Odor, in particular, allows larvae to
    distinguish between different environments, even adjacent reefs, helping guide them toward their
    preferred adult habitats. Many will head for far-flung locales
    miles away from their birth place. But some will use smell
    and other sensory cues to navigate back to the reefs
    where they were born, even if they remain in the
    larval stage for months. So, what happens when larvae
    do find a suitable coral reef? Do they risk it all in one jump
    from the water column, hoping to land in exactly
    the right spot to settle down and metamorphose into adults? Not exactly. Instead, larvae appear to have
    more of a bungee system. Larvae will drop down in the water column
    to check out a reef below. If conditions aren’t right,
    they can jump back up into higher water masses and ride on, chancing that the next reef
    they find will be a better fit. But this is the point
    where our knowledge ends. We don’t know the geographic movements
    of individual larva for most species. Nor do we know which exact environmental
    cues and behaviors they use to navigate to the reefs
    they will call home. But we do know that these tiny trekkers are more than the fragile
    and helpless creatures science once believed them to be. The secret lives of baby fish
    remain largely mysterious to us, unknown adventures waiting to be told.

    Diving the Great Barrier Reef | JONATHAN BIRD’S BLUE WORLD
    Articles, Blog

    Diving the Great Barrier Reef | JONATHAN BIRD’S BLUE WORLD

    August 21, 2019


    The Great Barrier Reef. It’s
    probably the most famous reef
    in the world, and the largest. It’s not just visible from the
    air, but from space. Hi, I’m Jonathan Bird and
    welcome to my world! (♪ music ) You know, it’s hard to believe
    I’ve been diving for over
    twenty years, and I’ve never seen the Great Barrier Reef in
    Australia, but today I’ve made
    it all the way to Cairns, and I’m going to get my chance. Cairns is a city in Queensland,
    the northeast state of
    Australia. The Great Barrier
    Reef runs 1600 miles along the coast
    of Queensland. It’s made up of millions of
    interconnected coral heads,
    forming the world’s largest living structure made by living
    organisms! To see the whole thing, you
    need to get pretty high up.
    This satellite image was made
    from 400 miles above the ocean. You
    can see the reef just offshore. For my first encounter on the
    Great Barrier Reef, I’ll be
    making the trip out on a big catamaran operated by Sunlover
    Cruises. The crew unties the boat and I
    enjoy the scenery as we head
    offshore. Ninety minutes later, I arrive
    at the Sunlover pontoon. I have
    never seen a dive operation like this before. The boat is
    huge, but we don’t dive from
    the boat. Instead we dock at this massive pontoon—sort of
    like a floating dive shop—and
    spend the day right next to the reef in a protected spot.
    Pure luxury! Time to check out the
    facilities! You don’t have to be a scuba
    diver to enjoy the Great
    Barrier Reef. The Reef is so
    shallow, you can snorkel! A lot of people who don’t dive
    love to come out and get a
    first hand look at the reef here. The water is clear and
    it’s not too deep. But even people who don’t like
    to get wet can see the reef. On
    a submarine! Well, tell you what – this is
    the easy way to see the
    underwater world right here.
    Just relax, sit back, have a drink,
    and watch the fish go by. And for a diving experience
    unlike any other, anyone can
    try the Sea Walker experience. All you need is a 40 pound
    helmet! I walk down the stairs
    into the water and the staff outfits me with the strangest
    piece of dive gear I have ever
    used. With no fins on, I just walk out to a massive
    school of fish. My hair doesn’t
    even get wet! This is incredible! They’ve got
    about a thousand fish around
    here. I feel like Doctor Sylvia Earle – deep sea diver.
    This is a very different way to
    go scuba diving, and this just goes to show you if
    you don’t want to wear a mask,
    don’t want to wear a regulator, and maybe you
    can’t even swim that well, you
    can do this! It’s just like walking. You know I’ve had a lot of
    experiences underwater, and
    this is definitely one of the
    most unique! To demonstrate how this helmet
    works, I have an ordinary water
    glass, which obviously is full of water, but if I turn it
    upside down, I can fill it with
    air. (Fills it with air) And now you can see that it
    keeps the air in, but if you
    turn it right side up – so we don’t want to turn this
    right side up. I pose for a picture, because
    you never know when you’re
    going to get to do this again! Next I meet Vance Fahey who
    will be my divemaster for a
    scuba dive on the reef today. JONATHAN: Oh, I can’t wait.
    Let’s get suited up. VANCE: Get right into it. JONATHAN: All right. (♪ music ) Well, let’s do it. Not only do I have a nice easy
    staircase to walk right down
    into the water, but a platform for putting on my fins. I can
    get used to this! On the platform is a group of
    new divers getting their first
    taste of the underwater world. At last I head out onto the
    reef to explore. I see many types of hard
    corals, beautiful pastel
    colored soft corals, and lots
    of fan corals. Near the reef, I find one of
    the largest Giant Clams I have
    ever seen. I can’t imagine how much this clam must weigh. The mantle gets its bright
    colors from imbedded symbiotic algae that harvest
    the sun’s rays for energy. I find a huge crack in the reef
    and have a little fun swimming
    through it. On the other end, I’m greeted
    by a sea turtle. She comes right over. There are
    lots of divers around this reef
    and this turtle knows that the divers won’t hurt her. Once she has decided that I’m
    not doing anything terribly
    interesting, she goes back to
    looking for her favorite sponges to eat. I turn and head back towards
    the platform across the shallow
    reef. At the platform I’m greeted by
    a friendly Mauri Wrasse. This
    monster of a fish reaches both the length and the weight
    of a motorcycle. I’m just glad
    they prefer to eat crustaceans and mollusks–not divers! I think I’ve made a new friend! Unfortunately, I’m low on air
    and it’s time to head back to
    my habitat up above. As we head back to the dock I
    reflect on a fun-filled day.
    It’s amazing how many things I did in one day on the reef! Well, I finally did it. I got
    to see the Great Barrier Reef,
    and I discovered that, of all the reefs I’ve visited, and let
    me tell you, that’s a lot of
    reefs, the Great Barrier Reef is probably the most
    accessible for everybody, from
    certified divers all the way to
    people that don’t even like to swim.
    There’s something for every age
    and experience level out here on the Barrier Reef. (♪ music )