Endangered Species Dating Profile: White Abalone

I intended to start a series of this kind of post with other endangered species, but applying for grad school, turning 21, and too many bs excuses got in the way. I will reboot this eventually! Enjoy the personal details of the beautiful White Abalone below!

BASIC INFO

Speices: Haliotis sorenseni

Nickname: White abalone

Picture: When cleaned up, looks like this:

But you probably see them like this:

But actually in the wild, they look like this:

Occupation: Gastropod, The Snail/Slug & Co.

Height: 5-8 inches

Weight: 1.7lbs

Age (lifespan): 35-40 years

Hometown: western coast of northern Mexico and southern California, not looking to move any time soon

INTERESTS/HOBBIES

Favorite food: algae, specifically drift macroalgae and red algae – yum!

Favorite show: The Last Man on Earth, This show is so relate-able, considering the density of me and my species is so low that we can barely reproduce – let alone choose who we reproduce with. Even when I’d think I’d never mate with someone even if he was the last man on Earth – let me tell you, it’s not just a phrase, it’s a reality – which brings me here.

Favorite color: shiny white – so shiny and pretty that people use my shells for jewelry.

Hobbies: deep sea diving – I’m the deepest abalone species in the world (living at 80-100ft), rock climbing (I live on rocks), reading Medieval romantic literature, and taking angsty, hipster selfies.

Zodiac Sign: Sagittarius

About Me (aka my baggage)

Not to sound vain or anything, but my main problem is that I am too beautiful for my own good. I clean up very well, you could say. Mexicans of the north love to just take hundreds of me out of the water, scrub off the algae growing on me, and turn me into lovely jewelry.

This has caused populations of me and my kind to reduce by 99%. Our density used to be 1 of us per meter-squared (1/m2), now we’re down to 1 of us per hectare (1/10,000m2).

This decimation has led to another issue area for us: sex.

Sadly, Viagara and other enhancement remedies can’t fix the problem. We are broadcast spawners, meaning that we release our eggs/sperm into the water, hoping they come into contact with and fertilize a different individual’s egg/sperm – talk about PDA!

(Such x-rated material pictured above – abalone porn stars openly spawning)

But because we are loners and our population density is so low, eggs and sperm between different individuals rarely meet and fertilize. So no new babies of us are made, causing our population size to exponentially decrease, as we are harvested from the sea.

On top of that, we tend to get sick with various infections.

My ideal partner: I’m looking for someone who is really down-to-earth and understands me. Ya know? Someone willing to boycott abalone jewelry sales. Even better, I would love to share my life with someone apart of the White Abalone Restoration Consortium. This group is currently helping me and my buds out by regulating the fishing of abalone and increasing our numbers in the wild through captive breeding – breeding us in aquariums and then setting us free. I’m also looking for someone who’s ready to settle down, as I plan on having a family some day to repopulate my decimated bunch.

Think I’m the one for you? Email me at sexyabalone@shellyeah.com

Got COTS?

**Disclaimer: Poor internet connection restricted my ability to add graphics and gifs. I’m deeply sorry for the absence of Spongebob in this post.**

Paper: Hock, K., Wolff, N. H., Condie, S. A., Anthony, K., & Mumby, P. J. (2014). Connectivity networks reveal the risks of crown‐of‐thorns starfish outbreaks on the Great Barrier Reef. Journal of Applied Ecology, 51(5), 1188-1196.

Have you ever seen something so beautiful, you could cry?

Same.

But I’m actually talking about something so beautiful yet so awful.

This beaut is a Crown-of-Thorns Starfish – a COTS. And it’s the worst.

COTS can wreak havoc on coral reefs during outbreaks. An outbreak is when the density of COTS on a reef exceeds the amount of food available to the COTS. And unfortunately, COTS like to eat coral.

Gobbling up a lot of a reef’s coral is extremely detrimental to the reef. Reef-building coral are the ecosystem engineers of reefs. They do not have a degree in physics, but they are a major component of habitat substrate in reefs. Their nooks and crannies provide places for prey, such as different types of fish and critters, to hide from predators, like sharks. Thus, coral is smart, coral is kind, but actually tho – coral is important.

So you might be thinking COTS outbreaks are the most terrible thing ever, but COTS outbreaks are actually like wildfires.

But aren’t wildfires bad?

No.

Wildfires can actually be a good thing. They kill off a lot of vegetation, but then new vegetation can grow. There’s a whole ecological concept behind what I just said, but you’re sick of my ramblings from last week so just google: intermediate disturbance hypothesis I linked he wikipedia article to that for you because I love and want you to be happy.

Similar to how the destruction of vegetation in forests can be a good thing, the destruction of coral by COTS in reefs can be a good thing.

HOWEVER. 

Ocean warming, ocean acidification, pollution, and other whatnot that have resulted from our treating the ocean like a garbage can intensify COTS outbreaks to the point where it gets really, really hard for a reef to recover before the next outbreak.

This study looked at COTS outbreaks in the Great Barrier Reef, which I’ll refer to as GBR because acronyms are the best.

COTS outbreaks in the GBR are mainly a local thing. —you wouldn’t understand—jk jk.

What I mean by local is that COTS are NOT eating up all the coral on the seafloor in the Great Barrier Reef like a vacuum sucking up all the stuff on a carpet.

No no no no.

They mainly just eat up the coral in the reef of their roots.

So how are COTS outbreaks a threat to so many reefs in the Great Barrier Reef (GBR)?

Like many marine critters, COTS produce planktonic larvae – larvae that goes with the flow, and rides with the tides, to wherever they begin to grow.

COTS larvae can travel in the water column from 9 to 42 days. What a huge range!!

So they have the potential to end up in pretty far places from their birth (making sure to call Mom at least every Sunday). Which means they can end up in new reefs, ready to prey on the untouched coral there. How delicious.

Reefs that have a lot of COTSs can lead to COTSs outbreaks. Outbreaks have been documented to occur in Cooktown-Cairns – northern end of the GBR and Swains region – southern end of GBR.

This study aimed to see how connectivity between reefs influenced a reef’s potential threat of COTS outbreak and predict COTS epidemics.

A COTS epidemic is the spreading of COTS outbreaks through connectivity between reefs.

A major theme of this study is POPULATION CONNECTIVITY.

I’m gonna focus on one point of the study because I’m already at 622 words and you’re proabably already bored.

Hypothesis: Reefs with connections to many other reefs have greater potential for COTS outbreaks.

What they did: This study was kinda math-y.Since larvae disperse in the water and “ride with the tide,” they generated simulations on a computer of larvae moving in water. Larvae were represented as particles. They used data collected from the spawning seasons of COTSs from 2006 til 2011.

Each reef was represented by a polygon and 10,000 particles representing COTS larvae were dispersed from each reef in the model. Since the larvae travel at such a range of time length, like I had mentioned above, the model generated larval movement over 28 days – as a compromise of the range.

The connectivity network was then analyzed. Arrows went between reefs representing the movement of a larva from one reef to another during the simulation. The more arrows incoming to a reef, the more larvae that reef received.

With this network, “superspreader” reefs could be identified. Superspreader reefs were described as those that have lots of connections to different reefs, and can, thus, cause COTS epidemics.

What they found: The superspreader reefs identified in the model matched the reefs that had been historically known for COTS outbreaks – the reefs at Cooktown-Cairns and Swains region.

Basically, the reefs that have the greatest potential to spread COTS and cause COTS epidemics were the reefs  that have had COTS outbreaks in the past.

Omg. The world is ending.

Not yet.

COTS outbreaks can be controlled, but the best solution is prevention. Like Smoky said, only YOU can prevent wildfires, only WE can really prevent COTS outbreaks.

Why this study matters: Only a small, select few of us can do the labor-intensive and expensive process of controlling COTS populations. Rather than treat COTS outbreaks only after they occur, the results of this study identified the superspreader reefs that could be focused. By controlling these reefs before outbreaks occur, other outbreaks can be prevented.

But remember, outbreaks can be a good thing. So our control of these hotspots can also mean allowing outbreaks to develop. But this way we can manage the extent.

Live Short and Prosper

Paper: Uusi‐Heikkilä, S., Whiteley, A. R., Kuparinen, A., Matsumura, S., Venturelli, P. A., Wolter, C., … & Arlinghaus, R. (2015). The evolutionary legacy of size‐selective harvesting extends from genes to populations. Evolutionary Applications.

The title of this post will make more sense once you read about r-strategists.

Raise your hand if you like seafood!

Same.

Being land-locked most of the year in PA, I don’t usually eat fresh seafood or any seafood for that matter. But in some places in the world, seafood is people’s primary source of protein.

Here’s a map of countries where fish is a major source of protein.

Fish is delish, but like everything else on this planet, fish is a limited resource.

While it seems like we have an infinite amount of fish, like Krabby Pattys…

we don’t.

Sucks, right?

We are overfishing the seas. This means that we are taking so many fish out of the ocean that the fish that are left can’t make enough baby fish to replace the ones that were caught.

Not only are we taking a ton of fish out of the sea, but we’re taking the big ones.

No one wants to eat a fish that barely has any meat on it.

By taking too many of the big fish, we’re left with more of the little guys. And since the little guys aren’t caught as much, there are more of them left to make baby fish than the big ones.

That’s like if all of the tall people on Earth were abducted by aliens and only short people were left on the planet to reproduce, the average humans in the next generations would be much shorter.

Aliens haven’t started doing that…yet, but we’ve definitely started doing that to fish.

Because only smaller tuna are left in the sea to reproduce, the average size of tuna has decreased dramatically. In the 1970s, the average tuna caught weight 1200lbs. Today, the average tuna weighs 600lbs.

From an evolution standpoint,

(I didn’t create this image)

it is likely that the tuna remaining may have also started investing reproductive energy into giving birth to smaller tuna but in higher quantities.

For those unfamiliar with energy allocation and evolution – I’ll try to explain the best way I can. Scroll down to “The Study”  if you already understand this ish.

From a biological standpoint, “success” is spreading the maximum amount of one’s genes to the next generation.  Like genetic world domination.

This biological goal pertains to everything from fungi to beluga whales to humas (but we’re a little more complex) .

There are two ways to pass on the most genes to the next generation*:

1. make a lot of babies

2. make really badass (big and strong to fight predators and obtain the most food) babies.

(very oversimplified, considered “theories”)*

It is too much to ask for both.

The limiting factor is: ENERGY

Energy – either from food or the sun (if you’re a plant) – powers life.

Reproduction requires energy. There are two overarching reproductive strategies of energy investment:

r-strategists: .

They make a lot of energetically “cheap” babies. They invest their energy into number of offspring instead of size of offspring. They opt for buying a 14 pack of disposable razors instead of going for the single, durable electric razor.

Some examples of r-strategists are flies, bacteria, mice, and barnacles.

The advantage: these organisms have more babies to pass on their genes

The disadvantage: the babies are less likely to survive long-term because they are relatively smaller and, essentially, weaker.

The likelihood of mortality is high, but the numbers are high to buffer that.

So if you start with ten baby mice all named Jerry and half of them die by actually getting eaten by Tom, you’re still left with five mice to reproduce and pass on genes.

Side notes: Because these guys make smaller, “weaker” babies, they tend to have shorter lifespans and reproduce at an early age compared to K-strategists.

Where the title of this post comes into play: Species that follow this reproductive strategy, live short lives, but they prosper.

K-strategists:

These guys make energetically expensive babies, but in fewer quantities than r-strategists. You could say these organisms are most successful by taking the “quality over quantity” approach.

Some examples of K-strategists include: humans, whales, and elephants.

(I really like narwhals)

The advantage: these babies are relatively strong and can survive pretty long

The disadvantage: fewer babies means fewer reproductively active individuals to carry out one’s genes.

While K-strategists don’t have a lot of offspring, offspring mortality is low. So even though you may only have two kids, there’s a pretty good chance both will survive long enough to reproduce.

Side notes: Because K-strategists have stronger babies, they tend to have longer lifespans and reproduce later in life. – they live long and prosper.

Most organisms fall somewhere in between r-strategists and K-strategist. Try to think of r/K strategies as a spectrum.

For instance, let’s say blue = K strategists and red = r-strategists.

Humans would be in the blue, dogs would be more like a violet-red, and mice would be in the crimson red of the spectrum.

Dogs have more offspring than us (humans) and their babies are smaller than ours, but a dog’s offspring are fewer and larger than rat offspring. So they aren’t really distinctly K or r-strategists. Few animals fall distinctly into r or K.

How does this all relate to fish and the study??

The Study

I know. I took a long, long time to set this study up, but think of how smart you is now. How much life makes sense! Why whale sharks are so rare and shrimp are so abundant!

Back to the study!

So this experiment looked at whether the reproductive strategy of zebrafish was affected by intense overharvesting of the big guys.

Hypothesis: By removing larger zebrafish from the zebrafish population through size-selective harvesting, the remaining zebrafish population would start reproducing smaller offspring in larger numbers at an earlier age –> exhibit a reproductive strategy closer to the r-strategists.

The Experiment:

(Tbh, not gonna get into the details. You’ve endured enough.)

Breed the zebrafish over five generations, removing the larger individuals each generation to mimic a typical harvesting season by humans in the wild.

Then, measure the average size of the zebrafish and analyze their DNA to see if a shift in reproductive strategy occurred at the genetic level.*

(I realize I oversimplified this concept, but I just want to get the message across)

A decrease in the average size could just be a surface (phenotypic/what we see) change. When I originally explained size selection, I mentioned how the average size of tuna could be smaller simply because there are smaller tuna in the sea left to reproduce.

However, a genetic analysis shows whether or not the fish are “intentionally” (for lack of a better word) smaller.

Aka, the scientists wanted to determine whether the youngest generation of fish are now genetically coded to produce smaller fish at earlier times and in larger numbers than the original generation of fish.

Genetic changes like this take a llllllooooooooonnnnnnnnnngggggggg time.

Because genetic changes like this can only accumulate over generations.

–But that’s another story. (I’m no storyteller. I pee greatness like gold is yellow. – name the song for $10) And I’ll save that for another day. —

In order for genetic change to accumulate and persist in the genetic code of the zebrafish population in this study, the zebrafish were bred (and big guys were removed) over five generations.

Only four generations of humans are pictured above, but we generally don’t live long enough to see more than three generations.

Results:

Of the fish in the fifth generation….

– The average adult body size at reproductive maturity decreased

– Genetic evidence confirmed that the fish invested more energy into reproduction than into body growth (hence, they were a smaller size and younger when they became sexually active)

– Because of their smaller size (and resulting reduced strength and dominance), the fish were less bold and explorative. They became scaredy cats -they had to be careful not to become somebody’s dinner.

This pug isn’t afraid of anything eating it. It’s just shy.

Moral of the Story:

Harvesting the larger fish of a species’ population over generations can cause the fish species to reproduce more, smaller fish.

More fish! That’s good, right?

More fish is great in the sense that the species is less likely to go extinct, but these fish are smaller fish.

They have less meat.

You’ll order fish and be like…

Ordering a pound of fish could mean combining the meat of multiple fish to reach one pound.

Which changes the quality of the meat.

The solution:

There are several angles to take.

– purchasing and ordering seafood from a certified sustainable fishery

these can bear the following logo on their packaging:

– following Monterey Bay Aquarium’s Seafood Watch Guide

– abstain from eating fish (the most sustainable choice, at least as far as my understanding lies)

As much as I love seafood, I am trying to eat only invasive species (ex: lionfish – another story for another post) because I am not certain truly “sustainably fished” seafood exists.

But seafood is an important source of protein to a significant portion of the world’s diet. And at least by following the guidelines in the Seafood Watch Guide or paying attention to what fishery one’s seafood comes from, the impacts of overfishing can be mitigated.

Thank you for taking the time to read this post. I spent a lot of time on it because I felt its contents were interesting and important, but that’s just my opinion. Let me know what you think!

Take a Deep Breath…Literally

Paper: Deutsch, C., Ferrel, A., Seibel, B., Pörtner, H. O., & Huey, R. B. (2015). Climate change tightens a metabolic constraint on marine habitats. Science,348(6239), 1132-1135.

Wooooowee is it hot out lately.

Every time I go outside…

But…

This hot weather is not only bad for Chris Pratt’s and my boob sweat (he could rock boob sweat anyway), but also terrible for breathing in the sea. Let me explain.

Aquatic life needs more than just water to live.

They also need air. And by air, I mean oxygen.

But how do they get air? They live underwater. If there was air down there, couldn’t we live there, too?

As you probably already know, but I’m gonna say it anyway, fish don’t actually breathe water.

Fish and other aquatic life breathe the little bits of oxygen that dissolved in the water, referred to as “dissolved oxygen,” DO.

You don’t need to read this whole diagram, but I just wanted to show what that means, kinda.
Basically, oxygen from the atmosphere mixes into the surface waters of the sea and critters can bring this oxygen.

Colder water can dissolve more oxygen than warmer water. But there’s enough oxygen – at present – in tropical waters for the sea life there to breathe.

Just look at all of those bubbles.

Anywho, the researchers of this week’s paper looked at how the reduction of dissolved oxygen in the sea (due to warming temperatures via climate change and overall loss of O2) will impact where different organisms can live based on their oxygen demands.

This was a pretty math-based paper, but don’t worry. We’ll get through this together.

(Leo is not only beautiful, he is also super passionate about the environment. Leonardo DiCaprio Foundation)

The scientists figured out how much oxygen each species they studied needed for their resting metabolism. Aka how much oxygen they breathe just exist.

Like this guy.

Obviously, these animals do more than watch cartoons all day and need more oxygen to catch dinner, avoid predators, and make babies.

Here’s where math starts to come into play.

The scientists defined “metabolic index” as the ratio of the amount of oxygen available in the environment, the supply, to the amount of oxygen the organism needs for its resting metabolism.

If this ratio is equal to 1: the animal can do no more than watch Netflix all day and just breathe

If this ratio is more than 1: the animal can hit the gym and catch tonight’s dinner and do lots of stuff

If this ratio is less than 1: the animal can’t even breathe and must do anaerobic respiration (aka breathing without oxygen) which they can’t do for very long before dying. they basically suffocate

The ratio across the globe did not vary much seasonally or longitudinally, but did vary a bit with latitude. Also, the ratio didn’t increase significantly in deeper water.

In the low-latitude tropical water, the ratios were pretty low:

1. there’s less oxygen in tropical water since it’s warmer there

2. organisms in warm environments have higher metabolic rates – aka need more oxygen for their resting metabolism

The tropical seas suffocate in their own beauty.

Meanwhile, closer to the poles, the ratio was much higher because the water holds more oxygen since the water temperature is colder and organisms there have lower metabolic rates.

As the average sea temperature increases due to climate change, the amount of oxygen in the water will decrease.

So the ratio of habitats close to the equator will decrease. For some critters, this means their ratio (oxygen supply:demand) in these locations could drop below 1 and they won’t be able to live there anymore.

Breathing issues, that is.

This study looked at how the ocean temperature projected for the end of the century – a bit warmer than today’s – will affect where certain species can live based on metabolic index ratios.

The animals examined spanned a variety of habitats.

Mid-latitude open ocean: Atlantic Cod

Mid-latitude benthic (bottom-dwelling): Atlantic Rock Crab

Subtropical latitude: Seabream

Subpolar latitude: Common Eelpout

V cute.

What they found:

In 100 years:

– cods will have to dive deeper in the summer to escape the warmed surface waters — they will have to take deep breaths – get it? breaths at deeper depths. The title of this post!

I’m so funny.

– rock crabs will have to move roughly 10 deg latitude north for more oxygen

– depth zones of organisms will shrink

– habitable zone of organisms will move toward the poles

However, not all of this will happen for sure.

Many factors affect how much oxygen is in the water.

Primary production (algae growth, etc) will affect the concentration of oxygen in the water. Algae and plants of the sea produce oxygen. When they die, they’re eaten by bacteria who use oxygen. So this relationship of primary production and oxygen concentration is a bit complicated.

The acidity of the ocean, which is projected to increase, could also affect dissolved oxygen concentrations. Additionally, pollution can impact oxygen levels.

From a biological perspective, some of these organisms will be able to adapt or the species could evolve over many generations to decreasing oxygen conditions. But that often takes many, many years depending on the species generation time and is unlikely to keep most organisms’ habitable range the same.

The only thing we do know for certain is that increasing temperatures have a negative impact on oxygen supply for organisms. So we should do our best to reduce our release of GHGs (green house gases – like carbon dioxide) and slow the warming of the seas!

Words from the Left Shark

Paper: O’Connell, C. P., Hyun, S. Y., Gruber, S. H., & He, P. (2015). Effects of barium-ferrite permanent magnets on great hammerhead shark Sphyrna mokarran behavior and implications for future conservation technologies.Endangered Species Research, 26(3), 243-256.

Left shark from Katy Perry’s Super Bowl show actually did not write this. But I bet he would if he had opposable thumbs.

In light of the recent shark encounters off the coast of North Carolina, this week’s article is about sharks.

I just want to remind you that as flawle$$ and delicious as you think you are…

sharks don’t actually want to eat you.

I hate to break it to you, but you are not nearly as tasty as a sea lion or other fish.

Look at that tasty, little seal. Yum.

While it has been widely known that humans are not on a shark’s menu, humans have been a part of some shark defensive and feeding behavior.

But like I said, this behavior is NOT specifically directed at humans.

I’m not saying it’s totally fine that those poor kids were severely injured, but I am saying that their injuries are no reason to start killing shark sprees because of this – like how the Jaws film generated that mentality and wiped out so many innocent.

((Really made me sad to Google pictures of this))

I totally agree that sharks are wild animals capable of harming humans. So we should be smart about swimming in their home, the ocean. Some measures have been taken to separate sharks from humans, such as nets.

However, more than just repelling sharks, these nets actually result in many shark and other animal deaths.

Speaking of hammerhead sharks, this paper specifically looked at hammerhead shark deaths by nets and experimented with an alternative to shark nets.

In a span of less than 20 years, about 1300 hammerheads died via shark nets in New South Wales, Australia. In South African waters, over a period of 15 years, roughly 3400 hammerheads died in shark nets.

Not cool.

Seriously.

So the scientists of this study decided to investigate the potential of utilizing the electrosensory capabilities of hammerhead sharks to devise a more eco-friendly shark repellent.

(Animal behavioral studies is a field very foreign to me so bear with me.)

The plan: use magnets as a shark repellent

Magnets can sustain their own field without an outside energy source, and they don’t capture sea turtles or other cuties like nets do. Such a sustainable solution. But wait.

I thought these sharks had electrosensors, not magnetosensors?

Here’s where your old best pal Faraday from physics class, who you used to think was…

is relevant!!!

When a shark goes through a magnetic field horizontally, an electromotive force is induced – according to Faraday’s Law. If a shark is swimming at 1 m/s, the shark can induce a voltage gradient at its receptors up to 25 uV/m (micro-volts per meter) – which is a much higher voltage than the minimum for shark detection.

If none of that sounded like English, basically (in a v brief sense), sharks can sense a magnetic stimulus indirectly by the magnetic induction of an electrical stimulus.

Now that we’ve got the physics taken care of…

we can move on to the experiment.

The study tested the effects of the magnetic field generated by a barium-ferrite (BaFe12O19) magnet on the behavior of the great hammerhead shark, Spyhrna mokarran, in two experiments:

Bait experiment

Barrier experiment

In each experiment there was a control (C), procedural control (PC), and a magnet (M).

While one experiment was specifically called “Bait experiment,” bait was used in both experiments to lure in sharks to the site.

This bait was none other than the most delectable, great barracuda.

Wow. My mouth is currently watering. How could any shark resist? In fact, how could any creature resist? I’ll tell you how. The barracuda bait was placed in a mesh bag so no other fishies could remove the bait.

The (Great) (De)Bait Experiment

In this experiment, each condition (C, PC, M) involved a PVC pipe. In the control, there was nothing but bait inside the pipe. In the PC, there was bait and a clay brick – serving to look identical to the M pipe. In the M, there was bait and the magnet. The brick and magnet were covered in black duct tape to make them visually identical. The pipes were placed over 1m apart randomly to eliminate side preference of the shark.

Here’s what it looked like:

The shark behaviors recorded were: visits, avoidances, feedings, and no reactions

Visits = shark swam within the observation zone

Avoidances = a visit followed be a sharp turn/acceleration away from the zone

Feedings = when a shark ate the food, duh.

No Reactions = when a shark did none of the above

The number of sharks present and number of sharks of the same species and different species were recorded for conspecific (same species) and heterospecific (different species) densities. Since sharks are presumed to be competitive, it was hypothesized that the presence of competitors would make them more likely to feed even though their electroreceptors didn’t agree.

Also, the scientists recorded repeaters, same shark at site more than once. These sharks were subsequently labeled Lizzie McGuires.

jk

The Barrier Experiment

In this experiment, a rope with some buoys spaced along were placed in the observation zones. In the control, the buoys had nothing attached. In the PC, the buoys had little bricks spaced out along ropes hanging vertically beneath each buoy with one giant brick on each to hold each rope vertically. In the M, the buoys had little magnets spaced out along the ropes hanging vertically beneath each buoy and one giant magnet on each to hold each rope vertically.

Here’s what it looked like.

The behaviors recorded in this experiment included: visits, avoidances, entrances, pass arounds, and no reactions

New behaviors definitions:

Entrances: visiting observation zone and swimming through the PVC

Pass Arounds: visiting observation zone and swimming parallel to PVC rope barrier but not swimming through or avoiding it

Data collection and statistics

The trials took place over two years and occurred during daylight. In the barrier experiment, the barrier containing the magnet was switched with a different treatment’s spot each trial to increase randomization. Each trial lasted 30 minutes.

While this took place over two years, the experiment was carried out on 19 days for the bait experiment and 17 days for the barrier experiment, which resulted in 90 trials of the bait experiment and 42 trials of the barrier experiment.

The data were run through various statistical tests to come up with a model that coordinated all of the variables signficantly. If you took STAT 462 Applied Regression with Steph, you could follow like two paragraphs of the Results section.

But the results section was longer than two paragraphs, and I got a little lost.

Like Alice.

But the experience was much less magical. I don’t recommend it for the non-stat oriented.

Here’s the bare bones of what they found:

Bait experiment:

Avoidances: C=0, PC=1, M=21 – there were statistically significantly more avoidances recorded of the magnet pipe than the other treatments.

Feeding: using fancy statistics, the scientists found there was a negative correlation with feeding frequency and presence of magnet. aka feeding frequencies decreased with presence of magnet

Barrier experiment:

Avoidances: the best fitting model the scientists generated showed that the presence of the magent was significantly correlated with avoidance frequency

Entrances: Entrance frequency decreased in the presence of both the procedural control bricks and the magnet. However, the magnet had the bigger impact on decreasing entrance frequency.

Pass arounds: Magnet presence was a significant predictor of pass around frequency. The presence of the magnet actually increased pass arounds – which likely means that the shark could detect the magnet – it stayed near the barrier but did not pass through it.

Both experiments:

Heterospecific/conspecific densities: when other species were around, entrance frequencies increased, but other than shark behavior was not really altered by more of its own species or other guys. It did what it wants.

So will magnets be used as shark repellents now or not??

More research needs to be conducted. The most likely situation would be that these magnets are dispersed along the entire depth of the water column so bottom-dwelling and surface-dwelling sharks are both deterred.

Another issue is habituation. Which basically means that a subject stops responding to stimulus after prolonged exposure. In other words, the shark could get used to the magnetic stimulus over time and begin to ignore it. If the magnets are moved around frequently enough the field will differ prolonging time to habituation.

For now, we will live with the shark nets, but many other sea creatures won’t.

If you take anything away from this post, please remember that sharks just want to live their life – even if we get in the way sometimes. One day, we will live in sustainable harmony with both left and right sharks.

Invader Sym…biodinium trenchii

Paper: Pettay, D. T., Wham, D. C., Smith, R. T., Iglesias-Prieto, R., & LaJeunesse, T. C. (2015). Microbial invasion of the Caribbean by an Indo-Pacific coral zooxanthella. Proceedings of the National Academy of Sciences, 201502283.

Believe it or not, this paper does not discuss early 00’s cartoons. But it does discuss invasions and possible doom.

Similar to the invasion of anchovies during the first episode of Spongebob ever, the invaders of this study are also quite hungry.

However, this invader is much smaller.

Invader: Symbiodinium trenchii 

Symbiodinium trenchii is an endosymbiotic dinoflagellate – unicellular algae – that resides in many coral species and gives the coral nourishment in exchange for a home. It’s more complicated than that, but that’s the gist.

To understand this study, I’m gonna break down coral physiology a lil bit.

Corals are animals. They are a colonies of tiny polyps, which filterfeed itty bitty food floating around in the water. For big reef-building coral species (hard corals or scleractinian corals), those little bits of food usually aren’t enough to keep the coral full and happy.

The coral just want some more, sir. They get more food by letting that unicellular algae, Symbiodinium, live in their skin. The Symbiodinium – often called zooxanthella – produces extra photosynthates – or sugars from photosnythesis – that the coral can gobble up as they please.

Also, the color of the zooxanthella in the coral gives the coral its color.

This diagram shows the coral polyps as the medusa looking things with zooxanthellae within the polyp. The hard coral’s calcium carbonate skeleton, “CaCO3 skeleton,” is also shown, hanging out underneath the coral polyps.

This skeleton is what gives hard coral their name. Hard coral deposit a skeleton and grow over it.

(See Dropping Acid for a better explanation)

Back to the paper:

Different species or types of zooxanthellae can reside in coral, such as Symbiodinium glynni and Symbiodinium trenchii.

Classifying these species and strains can get complicated. I don’t really understand it fully tbh, but what you need to know to understand this study is that different types of zooxanthellae can live in coral and that these zooxanthellae give the coral food via photosynthesis.

So this study looked at which Symbiodinium were living in the Indo-Pacific vs. the Caribbean.

vs.

The sampling from the Indo-Pacific was at two locations: Adaman Sea (eastern Indian Ocean) and Palau (western Pacific Ocean).

Sampling from the Caribbean was very widespread: Barbados, Belize, Curaçao, Florida Keys, Flower Garden Banks, Mexico, Panama and St. Croix.

Here’s a better pic of the sampling:

This is Figure 1 from the paper. We’re just gonna focus on the map parts of this figure for now. The Indo-Pacific coral sampling locations are shown together in A, and zoomed in is B and C. B is the Adaman Sea and C is Palau. D shows the Caribbean sampling locations.

((structuring the rest of this like the paper bc I really like the way the paper was organized))

Symbiodinium diversity in the Indo-Pacific:

While the two sampling sites in the Indo-Pacific were far apart, the coral colonies sampled at each site were pretty close together, sometimes only 10km apart. Even at these small distances, the diversity of Symbiodinium was super high.

If you look back at figure 1, the black portions on the bar-graphs at B and C represent unique genotypes of Symbiodinium found there. (Genotypes describe the genetic makeup of an individual – I won’t get into specifics of this paper, but basically like we’re all humans but all different genotypes, the Symbiodinium found there were mainly all different genotypes.) Few coral had the same genotype of Symbiodinium in their tissue. The colored regions on the bar correspond to the same genotype. In the Indo-Pacific bar graphs, you can see there are only a couple short colored portions.

Basically: The Pacific had high diversity of Symbiodinium even over short distances between coral colonies.

As for the Caribbean:

The sites spanned widespread distances, and the coral colonies sampled at each site were up to hundreds of km apart. However, clones, same genotypes, of Symbiodinium, resided in coral even thousands of km apart. The most common genotype of Symbiodinium is represented in the red colored block, which was found frequently at all locations. The unique genotypes, represented in black, is a very small portion of the bar graphs compared to the Indo-Pacific graph.

In short: The coral sampled over much further distances in the Caribbean often had Symbiodinium of the same genotype, aka low Symbiodinium diversity.

On top of that, none of the genotypes found were unique to the Caribbean. The genotypes were all also found in the Indo-Pacific. In contrast, the Indo-Pacific had a ton of genotypes that were only in the Indo-Pacific and not in the Caribbean. Figure 2B from the paper shows a gene tree of all the genotypes uncovered in the study.

The little red group in B shows the Symbiodinium genotypes found in the Caribbean/Atlantic, the orange = Indian Ocean and blue = Pacific Ocean. As you can see, the Caribbean genotype varieties are much fewer and clustered together compared to the other regions’ genotypes, spanning the length of the graph.

In C of figure 2, the distribution of genotype diversity observed was compared to the expected diversity of the region. The expected diversity is shown in white and has a bell-curve shape. The observed diversity is in dark gray and the overlap between expected and observed is in light gray. In the Atlantic, you can see the observed is greatly skewed right – suggesting much lower diversity than expected, where as the Indian and Pacific genotype diversity graphs almost match the expected diversity curve.

Basically: There is significantly less Symbiodinium diversity in the Atlantic/Caribbean than in the Indo-Pacific.

The most common genotype of Symbiodinium found in the Atlantic was a variation of Symbiodinium trenchii.

What’s so special about Symbiodinium trenchii?? Why does it dominate?

When coral bleach – lose their symbiotic algae Symbiodinium – because of warm temperatures or other stressors, they can either recover (get a symbiotic algae back) or die.

Certain Symbiodinium are better adapted to hot temperatures, unlike poor Goofy.

So these Symbiodinium are more likely to colonize the coral tissue before the zooxanthellae that can’t handle the heat as well have the opportunity.

Symbiodinium trenchii is one of those guys that can handle the heat.

Not quite that hot, but warmer temps than other Symbiodinium.

This study then looked at how well this S. trenchii performs in the coral species, Orbicella faveolata.

(figure 3A from the paper)

((This is the first species of coral I’ve ever worked with *nostalgia*))

The O. faveolata colonies this study looked at originally had the Symbiodinium types: A3, B17, C7 (like I said, don’t ask me how they classified them)

They looked photosynthetic rates when the O. faveolata colonies had their usual symbiont in them and compared that to when these colonies had S. trenchii. based on oxygen evolution (see the paper’s supporting info for what oxygen evolution is – I don’t fully understand).

As you can see in Figure 3B from the paper, the maximum rate of photosynthesis (Pmax) with the different symbionts in the coral was not much different when S. trenchii was in the coral colonies.

Aka, S. trenchii produces relatively the same amount of photosynthates when living in the coral which it is not originally adapated to live in.

HOWEVER, the coral did not calcify (make their calcium carbonate skeleton) as much as when S. trenchii was in the coral compared to when their original symbiont was in them at high temperatures.

Figure 3C shows the calcification rates of the coral at different temperatures when the different symbionts were in the coral. Red = S. trenchii, Yellow Green and Blue = the other symbionts.

When temperatures reached like 28 deg C, the coral with S. trenchii started depositing significantly less skeleton than the coral did with their original symbionts.

What does this mean??

S. trenchii is an opportunist microbe that colonizes coral during times of high stress, like high temperatures. While it can photosynthesize the same amount in the O. faveolata as other symbionts, S. trenchii keeps more of those photosynthates for itself, rather than giving more to the coral. Like I said earlier, it’s a hungry invader.

Because S. trenchii keeps more of the photosynthates, its host coral calcifies less. If the coral cannot produce a strong enough skeleton, the coral is more likely to break a leg. Except coral don’t have legs, so they just break into pieces, unlike this cute puppy.

The advantage of S. trenchii and why it is so dominant in the Caribbean/Atlantic is that temperatures are increasing in the Atlantic as the world warms due to climate change. With the water being warmer, coral are more likely to bleach more frequently and for longer periods of time. Since S. trenchii can handle higher temperatures, it is more likely to colonize bleached coral before the coral’s original or similar symbiont can recolonize.

The plus side of S. trenchii‘s existence is that if temperatures are too high for too long and that the coral is likely to die, S. trenchii can slide in and give the coral some food.

But not enough food. S. trenchii could be problematic if the coral aren’t able to produce enough skeleton to grow big and strong.

I’m not gonna get into the detailed genetic explanation, but because Symbiodinium trenchii is a genotype found a little bit in the Indo-Pacific, but clonal and widespread in the Atlantic, it is likely that S. trenchii was introduced to the Atlantic via ballast water of ships coming through the Panama Canal. And then S. trenchii took over coral in the Atlantic during bleaching events.

So you could say Atlantic/Caribbean coral experienced an invasion of S. trenchii like the musical world experienced in the 60’s.

Except the invasion of S. trenchii is not a good thing and doesn’t involve British bands. S. trenchii‘s invasion gives it merit to be deemed an invasive species for several reasons:

– opportunistic, widespread colonization in the Atlantic

– host generalist – can colonized a bunch of different species of coral

– negatively impacts coral growth

More studies need to be done to completely confirm all of the above, but this study showed pretty compelling evidence that S. trenchii could star in the next kids cartoon called Invader Sym.

East Coastin’

The last few weeks have been a whirlwind, but my weekly posts are finally returning for the summer!!

I know, I’m so excited too. ((I also do not know who that man is, but I am really channeling him right now))

What’s been going on? What could I have possibly been up to for the past month?

…I wish I had been that stranger above! I did get to decompress a bit after finals, but never to that point.

I started my internship at Harbor Branch Oceanographic Institute in Fort Pierce, FL this past Tuesday.

The building I work in is covered in trees.Of course.

Fort Pierce is on the Atlantic coast of FL. Last summer, I was along the Gulf side. I can’t tell which side I like better. The water of the Gulf was super warm – which I like – but had no waves. The water of the East Coast has waves, but isn’t super warm. A final verdict will be made at the end of the summer. Stay tuned.

I’m living in an apartment on-site – like a seven minute walk away – so no excuse of bad traffic for being late.

Back to science!

Yes, I am, in fact, working with coral again this summer.

The species: Montastraea cavernosa ((and potentially Pseudodiploria clivosa))

M. cavernosa is the only Montastraea coral left in the genus after the re-classification of many Montastraea coral to Orbicella.

The experiment: analyzing the shift in composition of the bacterial communities of M. cavernosa mucus before and after exposure to freshwater discharge water

Basically, coral have a mucus layer on the outside of their tissue.

The yicky, white, cloudy stuff is the mucus. But it usually doesn’t shed like that. It just chills on top of coral at all times. So you don’t really even see it.

Some of the bacteria in this mucus have been found to help coral acquire nutrients (like the coral’s photosynthetic algal symbiont Symbiodinium) and other bacteria have been found to produce antibiotic compounds to prevent pathogenic bacteria from colonizing the coral and causing disease.

In this picture, the disease is that black strip which kills the coral as it grows along. The dead part of the coral is the white part, which can then get colonized by algae and other stuff – the fluffy stuff in this pic.

Anyway, back to my project.

So I’m seeing if freshwater discharge has an effect of what types of bacteria are chilling in the mucus.

What do I mean by freshwater discharge?

The dark water is the freshwater, the lighter water is the ocean water.

How does this much freshwater get to the sea so fresh? It’s not discharge from a river.

The water comes from Lake Okechobee – which is decently far inland. So how does its water get to the coast?

Way back when, the dam system for Lake Okechobee could have used repairs, but nobody did anything about it. Eventually, the water level of the lake began to overflow.

To direct the freshwater from flooding everywhere, a canal system was built.

My labmates have a better map of the canals, but this picture shows the St. Lucie Estuary Drainage Canal, which is the source of the discharge water that affect the coral in my project.

These canals used to release freshwater the entire FL rainy season. However, now they only open and shut as needed.

I will be looking at the mucus of M. cavernosa right before the canals were opened in June of 2014 and after the canals have been opened for two months – in August 2014.

How will I characterize the composition of the mucus?

NEXT GENERATION SEQUENCING

Put simply, I will be looking at which bacteria are present based on DNA sequences. If one of the DNA sequences from the mucus matches a known bacterial species, then this bacteria is present.

Simpler, cheaper methods of sequencing enable you to classify a sample at Phyla level.

But, as you can see, this analysis isn’t very specific. If only a few species are expected to be different for my project, I need much more specific analysis of the mucus.

Which leads us to NEXT GENERATION SEQUENCING.

Next Generation Sequencing – I will call next-gen for short – is kinda complicated for me to explain here. But basically, it will figure out which bacteria are present based on reads of sample DNA. Sometimes you only needs a few thousand reads of the DNA to identify all of the species present in your sample, but sometimes you need like 500,000.

The more diverse you expect your sample to be, the more reads you need to catch every species – which may only be present at 1%.

No one has ever performed next-gen sequencing on the bacterial community of coral mucus ever – let alone that of M. cavernosa‘s mucus. Every species of coral’s mucus is different.

Thus, I have to figure out how many reads I will need based on literature search and educated guessing.

The challenges with educated guessing are:

1. The samples will need to be sent to a facility and the sequence data can take many weeks to get back. I might not have any data by the end of my internship. =[ This isn’t a huge deal because I could analyze the data at Penn State when I get back, but it would be nice to have the data to present and write my paper for the internship.

2. Next-generation sequencing is super-duper expensive. We really wouldn’t want to have to do this twice if I picked a number of reads that was too low.

aka I have ONE shot at picking the number of reads.

*cue “Lose Yourself” by Eminem

Why not just pick a really high number of reads – like a million reads – to ensure all the diversity is detected? It is expensive.

I will also be performing LHC-PCR, which is less specific than next-gen, but if these data show differences in the communities, we can get a better idea of number of reads we will need.

So I’ll have the LHC-PCR data to work with if next-gen takes too long.

But this will be me once I get the next-gen data:

Wish me luck. My mentor had described me as “one of those students with an incredibly, overly ambitious project.” Why didn’t he stop me????

Well, here goes nothing!

Nautilus aLIVE

How did I spend my last two weeks of classes this semester? In the Gulf of Mexico. Abducted by pirates.

jk. This was the closest I came to seeing pirates.

Not sure why, but this boat with some fishermen sailed right next to the ship and didn’t say anything, then sailed away.

Anyway, I was replacing someone from the USGS, who had to attend a different cruise last minute. I worked with Jennie, a researcher from the USGS, processing sediment cores for macrofauna and meiofauna analyses (basically, we were collecting mud to look for microscopic animal composition).

We left out of Gulfport, MS…

The first day, I explored the ship.

The deck

The bow

The control van

The dining area

The lounge

The upper deck outside

We were pretty close to oil rigs.

Above is an oil rig. In some locations, oil rigs glittered the horizon.

While the ship sailed to our first dive location, we spent learning about safety and doing fire drills. We also had a science meeting to discuss what was going to take place during the upcoming dives.

That’s a picture of one of the captains in a safety suit. Looks pretty sweet.

The main purposes – from my simple-minded understanding – of each dive was too: image corals, collect sediment core samples, and collect samples of coral.

What I mean by “dive” refers to the dive of ROVs (remotely operated vehicles), deploying to depths of up to 1800m (they can go much deeper than needed for this cruise). ROVs can be used to collect samples, take pictures, and film the deep sea, while it is operated on the surface by pilots and directed by scientists.

On the E/V Nautilus, two ROVs are deployed at the same time each dive.

Argus

and Hercules

Hercules’s job was to traverse the seafloor, collect samples, and take images of coral with the “beast” cam. aka Hercules did all of the flashy stuff.

Argus’s job was to absorb the wave action of the water column and hover above Hercules with a camera so the pilots could better visualize how to move Herc – (Hercules is called “Herc” for short). Below is a view of Herc from Argus during a dive.

The names “Argus” and “Hercules” were taken from mythology. In Greek mythology, Argus is a 100-eyed giant, protector of heifer-nymph lo – which sort of relates to how Argus kind of protects Herc. Hercules was named from the Greek hero Heracles, who had ten labors to carry out – similar to how Herc performs the tasks of the dive.

Here’s what Herc looked like as it surfaced at night. Some scientists joked it looked like aliens emerging.

Anyway, the majority of people’s schedules on the ship revolved around their watch time. I don’t mean the time on their watch. I mean the time that they take part in monitoring the ROV dives. Being on watch means sitting in the control van and recording observations, taking images, controlling the cameras, navigating, or piloting the ROVs, depending on your role. Below is an image of what being on watch looked like for this cruise.

Watch schedules were four hour shifts twice a day. My watch shifts were 4am-8am and 4P-8P. The other ones were 12-4 and 8-12.

You only had to be on watch when the ROVs were in the water. Thankfully, I only had to wake up once for the 4am-8am watch. However, one time I woke up for my shift at 4am, but the ROVs were surfacing earlier than expected. They were pretty much on deck by the time I woke up so right away Jenny and I started processing samples.

Processing sediment samples typically went like this:

Step 1. direct pilot in taking push cores at end of dive, which looked like this

Step 2. retrieve push cores from Herc

Step 3 get cores out of quivers

Step 4 push core visual profile. Jenny would use a tape measure and describe the different layers of sediment in the core, as I recorded her observations on a sheet. I’d also take a picture of the core.

Step 5: remove top water, place core on “push-pop,” and begin slicing the different sections. This was the most time consuming part of the process.

I’m holding up the sediment core while Jenny uses a fence and slicer (idk what it’s actually called) to collect sediment in three different fractions: 0-2, 2-5, and 5-10cm. After each slicing, the sediment is stored in Nalgene bottles.

Every little speck of mud could contain hundreds of meiofauna so cleaning off the sediment between each slice took a while. In the picture above, I was looking at my glove to make sure I didn’t have any sediment on my fingers.

In the picture above, the “slicer” is in my left hand.

Above is a picture of the wet lab we worked in. Sam and Styles on the right were preparing coral samples for shipping.

Step 6: sediment chemistry. Only one of the five cores was used for this. Another collaborator of the cruise wanted a sample from the top five cm of sediment for carbon dating. We had to section the sediment into 1cm increments for this researcher. That took forever. Sediment chem also involved measuring the sediment’s salinity at each layer (0-2cm, 2-5, 5-10) and the overall redox value of the core.

Measuring salinity was my favorite part of the process. You would take a blob of mud and put it in a syringe and squeeze the mud through filter paper so that only the water would leak through onto the refractometer. Sometimes the mud was so thick I didn’t think any water was in it, but there always was. I loved seeing the clear water come out of a thick clay.

Anyway, when all the macrofauna processing was done for four of the cores, and sediment chem done for the one, I would was the cores to prep for the next dive, while Jenny topped the nalgene bottles of sediment off with formalin, then seawater. We then would invert the bottles over and over to make sure the formalin penetrated the sample. Finally, we would tape up and parafilm the caps so nothing would leak out and put them away in an action packer – an exciting term for a storage tub.

At one point in the cruise, we pretty much had to switch to doing sediment chem for 6 push cores – which took so so so long. Usually, not every core made it to the top successfully so it wasn’t that long every time.

We played music a lot and talked and time went really fast!

Coral Imaging: Most of the coral imaged on this cruise had been imaged in previous years. The purpose of taking photos is to track damage and recovery of coral impacted by the oil spill. Damage was looked at by comparing photos of the coral from each year to the next. This meant that the pictures must be taken in the same location and angle as the previous pictures.

You might wonder, how the heck do coral eat in the deep? Marine snow. Fluffy snowflakes, each unique, float down from ski mountains…jk. Marine snow – the specks of white organic material that floats from the surface to the deep. This organic material can be bits of fish flesh or balls of phytoplankton which stick together as they sink.

Those white specks aren’t dust on the camera. They’re marine snow. However, the big white thing in the picture is a deep sea urchin.

This is also a picture of a typical coral found in the deep, hugged by several brittle stars.

The pictures of the coral were taken with a “beast cam” – really really really high quality camera – that’s screen was visualized on the surface. For the first week or so, my laptop was the only computer which allowed the camera program to run.

Above is Fanny taking pictures of the coral with Dr. Fisher.

Above is Sam focusing the camera onto the coral with a multi-focus grid.

This is a pic of people figuring out where the next coral is located. You can see the back of laptop covered in stickers.

Colonization of coral by hydroids is a sign of damage. Above is a coral colony (tan-ish color) whose left side is colonized by hydroids – the bright yellow stuff.

The coral images are looked at for progression or retreat of hydroids over the years.

Coral Sample Collection: Sam and Carlos’s work involved collecting coral samples for various analyses back on land so their time was spent preserving the coral samples. Here’s some pictures of their work.

Overall, the weather on the cruise was pretty pleasant. We had one rainy day, which many of us spent watching Life Aquatic.

There were some critter visitors on the surface: sharks, dolphins, birds.

People would throw meat into the sea and the sharks would come flocking.

For the last dinner, there was a big bbq celebration.

And it ended with a beautiful sunset.

All the sunsets and sunrises were beautiful. My photostream was 90% sunsets and sunrises by the end of the trip.

The only thing more beautiful than the sunsets was the blueness of the water. I never saw water so blue.

This picture doesn’t even do it justice.

Why it must be Greased Lightning!

This week’s topic: Deep sea communities and Coral-algal symbiosis

Paper: Fisher, C. R., Demopoulos, A. W., Cordes, E. E., Baums, I. B., White, H. K., & Bourque, J. R. (2014). Coral Communities as indicators of ecosystem-level impacts of the Deepwater Horizon Spill. BioScience, 64(9), 796-807.

Coincidentally, this past week in class, Dr. Charles Fisher, the professor I’m going on the cruise with, was a guest lecturer. To prepare for the cruise, he gave me some papers to read so this week’s post is about one of those papers, which talks about…

…you guessed it – grease! …kind of… Oil, to be more specific.

On April 20, 2010, as many of you know, tragedy struck the Gulf of Mexico. The Deepwater Horizon Spill released about 800 million liters of oil 1500m down in the ocean.

The oil impacted everywhere from the surface…

To the shore…

Even to the depths…

But wait….

I thought oil floats on water??

There are actually a lot of factors that caused the oil to sink to the bottom of the sea.

– burning of the oil

– use of oil dispersant

– natural weathering processes

That’s a picture of a plane spraying oil dispersant. Below is a diagram of how oil dispersant works – and how it gets oil to the deep sea. (The brown is the oil)

This paper explores many different assessments of the spill’s impact on deep sea communities, but I’ll only talk about a couple.

1. Impact of Deepwater Horizon Spill on deep-sea coral communities

Using remotely operated vehicles (ROVs) and other technology, the researchers of this study located coral communites about 13km or 8 miles from the wellhead and photographed images of the coral colonies.

Roughly 72% of the coral colonies they looked at from this site were affected by the spill. Over half were covered in what is referred to as floc – the brown mix of oil and dispersant. They returned to the same sites 5 times over 16 months to track the damage.

Color key: the white parts are alive, the black parts of the coral are covered in floc, and the yellow/fuzzy parts are covered in hydroids – a sign of coral decline.

More coral colonies were looked at 30 km or 18.5 miles away from the wellhead and 68% of those colonies were impacted.

How did they know it was oil from the oil spill and not just natural oil leakage of the Earth??

This is a random hydrothermal vent. I don’t think this one is seeping oil specifically, but that’s what seepage looks like.

To get to the bottom of whether or not the floc was from the spill or not, the researchers did some fancy chemical analyses.

And found that there was a 0.0001 chance that the oil was from a natural process that had landed in the sediment and on the coral. I repeat, 0.0001 chance.

The content of the floc wasn’t 100% the same as the oil from the spill, but this is largely because the oil’s interaction with the very low temperatures, high pressure of the deep sea, and interactions with the dispersant, which all altered the oil’s properties.

In short, the Deepwater Horizon Oil Spill greatly impacted its surrounding deep sea coral communities.

2. Impact of the oil spill on soft-sediment communities

The “soft-sediment communities” discussed in this paper refer to the critters that live within the deep sea mud. (I will be working with these guys on the cruise.)

The types of organisms living in the sediment in this study served as bio-indicators of oil presence. A bio-indicator is an organism whose presence can suggest particular aspects of the local environment. For instance, certain coral species are really sensitive to temperature change and so they are great bio-indicators of an area’s temperature.

In this case, species from the crustaceans (left) and amphipods (right) pictured below…

are particularly sensitive to oil

So if an area was impacted by the oil spill, it is unlikely that species from these groups of organisms will be crawling around.

On the flip side, polychaete (left) and nematode (right) species are more tolerant of oil.

So these lovely looking creatures will be more common in the sediment of areas effected by oil than the amphipods and crustaceans.

The sites were sampled for these critters by taking sediment cores. Many of the sites examined were close to the coral communities anaylzed. They found the following proportions of groups of critters in the samples.

The Polychaeta and relative Oligochaeta groups dominated most areas. The sites sampled are labels under each bar.

Site MC294 is 13km from the wellhead and shows a significantly high proportion of polychaetes!

Basically, the small proportion of crustaceans and high proportion of polychaeta and its relative oligochaetes further show impacts of the Deepwater Horizon Oil Spill on the deep sea.

Oil spills impact much more than meets the eye. I’m not discouraging the use of oil dispersant because clearing surface waters is pretty darn critical to marine ecosystems, but maybe a more organic and less invasive mechanism could be developed to clean up oil spills.

OR…. we should just stop using oil. Like right now. Let’s switch the grid to solar! Today.

…idk why I added this gif. I just really like Kenickie. He’s my favorite.

Perks of Being a Squeaky Wheel

This post isn’t about a paper. It’s about some pretty big news that will affect my blogging for the weeks of 4/19 and 4/26…..

I’m going on a research cruise in the Gulf of Mexico with the Fisher Lab at Penn State for two weeks on the Nautilus!!

I am beyond excited!!!

How did this happen? I don’t even work in the Fisher lab?

The title of my post sort of explains it…

I work in Baums Lab, which neighbors the Fisher lab. One day, a graduate student of the Fisher lab was eating his lunch in Baums lab. He was talking to the Baums lab tech about the research cruise both labs are going on. He mentioned that none of the undergrads in Fisher lab could go because of their finals and exam schedules. (Baums lab didn’t need me to go)

I was shocked. Who gives up the opportunity to do deep sea research??

I told the grad student I would totally go, but apparently the spot was filled already by another grad student.

Here’s where I became a squeaky wheel. I emailed Dr. Fisher and asked if – in the very small chance – a spot opens up on the cruise, I would more than love to go.

He responded that everything was booked.

I figured that was the case, but ya never know!

….and you never know!!

This past Monday, he emailed me asking if I was still interested in going on the cruise. Apparently one of his collaborators needed a volunteer last-minute.

I responded yes to his email in 30 seconds.

So, here I am. I should be studying for a major virology exam I have tomorrow, which I need to do well because I am going to miss the final.

But I really wanted to share what’s going on. And explain why I won’t be posting for the week of 4/19 or 4/26.

The cruise will be leaving from Mississippi for the Gulf of Mexico.

I don’t know too many details yet, but apparently I’ll be working with marine invertebrates in the deep sea sediment, or mud.

So this will basically be me the whole trip.

Cannot wait.

P.S. I will still be posting about an article this week.