These bada$$ carbons are “isotopes”, sort of like fraternal twins (or triplets/quadruplets) where one is blazing their own path.  One of the twins is your regular Joe Shmoe who follows the rules and does everything by the book.  These are the ones shown in the periodic table.  The other twin in each set has the same number of protons as its boring twin, but it doesn’t follow the rules about how many neutrons they are supposed to have. They’re greedy little thieves. So, they are technically the same element, but they end up weighing different.  For instance, Carbon-13 has his regular six protons like its brother, but it has a whopping seven neutrons because it just haaaad to go and be extra cool. 

Almost every element has some number of isotopes/twins, except weird ones like Thulium and Holmium – but who even are those guys? Now, the wrong-number-of-neutrons outlaw twin can either be “stable” or “unstable”.  It’s like the difference between the cool guy in class and the guy who is so “cool” that he ends up expelled from school.  The stable ones are functional in society – in this case meaning they occur in nature without a problem.  The unstable ones are completely dysfunctional and over time try to turn back into their more stable twins by shedding neutrons.  It’s kind of like they just went too neutron-crazy, got a little wild, and now they’re all bloated and not having a good time. 

Knowing about these different carbons is important because stable isotopes can help reveal food webs.  Naturally occurring carbon consists of both the normal carbon and its bad boy twin.  We have a method that allows us to measure the ratio between the outlaw and the normal (we call this ratio the isotopic ratio). By measuring the carbon isotopic ratio of an animal, we can answer questions like what did this animal eat, what level consumer are they, and even what kind of eater are they (suspension feeder, predator, etc). This is especially important in my work because I want to understand how carbon from land makes it into the deep-sea food web. When I drop a big hunk of land carbon in the form of an alligator or a wood log (wood fall), I first measure the ratio of good boy to bad boy carbon in that particular hunk of food.  I also collect samples of the sediments around where I drop the food and measure the ratio of carbons in that sample too.  Then, after letting the food stay on the bottom of the ocean for a while, I can take animals directly off of it and take similar animals far away from the it.  When I measure the ratio of carbons in these animals, I can compare them to the ratio of the two food sources I measured and can understand which food source the animals are using.

The reason this all works is because of the saying “you are what you eat.”  Turns out that is actually true!  We know how much the good boy to bad boy carbon ratio should change from a food item to its consumer. This is especially helpful as we begin moving up the food web, because we can start to see who is eating whom – and this is something not yet well understood in the deep sea.

The post You are what you eat! Using bad boy carbons to understand food webs first appeared on Deep Sea News.

The video is the actual video from my research group’s dive with a remotely operated vehicle in the deep Gulf of Mexico. The background on all this alligatorfall project and why a bunch of scientists would sink an alligator in the first place is in our previous post. You can also read Atlas Obscura’s great write up on our work.

The post The Video of Giant Isopods Eating an Alligator in the Deep Sea You Must Watch! first appeared on Deep Sea News.

Wait…what? What kind of mad science is this?

What you need to know is that the deep oceans, encompassing depths below 200 m, cover most of Earth and are especially food-deprived systems. Primary production of carbon is minimal only occurring through alternative pathways such as chemosynthesis. However, chemosynthesis is a tiny fraction of total ocean production (0.02–0.03%) and the energy that sustains most deep-sea organisms is sequestered in sinking particulate organic carbon derived from plankton hundreds of meters to kilometers above near the sea surface. At the abyssal seafloor, this sinking particulate organic carbon represents less than 1% of surface production.

This minimal amount of carbon available opens the door for more unique sources of carbon. Enter food falls and aligators.

The remains of large plants, algae, and animals arrive as bulk parcels that create areas of intense food enrichment. Deep-sea scientists have explored these food falls through both naturally occurring and experimentally deployed wood (#woodfall) and plant remains, cameras baited with animal carcasses, chance occurrences of and deployed intact whale carcasses several miles deep on the seafloor. These experimental and natural food falls have revealed the important role they play in deep-sea diversity. Many of these large food falls on the deep-sea floor, host highly diverse and endemic suites of organisms in kind of food island. In addition, food falls may represent significant transport highways of carbon into the deep oceans. For example, during Typhoon Morakot, wood was estimated to carry a total of 4*10¹² g of organic carbon into the oceans, nearly 25% of the total annual riverine discharge of organic carbon in the same region. On the deep-sea floor, a single wood fall can enrich sedimentary organic carbon by >25% even after several years.

But why alligators? With regard to animal falls, prior work as focused primarily on whales and other cetaceans, pinnipeds, large fish such as tuna, and elasmobranchs. However, it very likely that marine reptiles both currently, and even prehistorically, are an important source of carbon in the deep oceans. Before the existence of whales, perhaps large marine reptiles like ichthyosaurs, mosasaurs, and plesiosaurs hosted diverse and endemic invertebrate communities on sunken carcasses, similar to modern-day whale falls, and contributed significantly to the deep-sea carbon budget. From ichthyosaur and plesiosaur remains, there is evidence of molluscs that are also associated with Eocene seeps. A fossilized limpets are also found in close association with the bones of a fossil leatherback turtle from the Middle Eocene. In the modern oceans, carcasses of Alligator mississippiensis serve as the closest modern analog of ichthyosaur, mosasaur, plesiosaur food falls.

Alligator carcasses in the deep ocean are also not as nearly impossible as you might think.  Both live individuals and carcasses of alligators are frequent on beaches and in coastal surf.  A 3-meter individual came ashore at Folly Beach, South Carolina in 2014 and in 2016 a carcass of a 4-meter individual washed up on a beach in Galveston, Texas.  These individuals of A. mississippiensis may be easily carried offshore by major rivers or during large storm events, tropical storms, and hurricanes.  Live A. mississippiensis have been observed 30 kilometers offshore and after Hurricane Katrina in 2005, an alligator was found 25 kilometers offshore. During the 2011 Mississippi flood event, several dead alligators were observed in the mouth of Atchafalaya River.

Thus, I am on ship, 100’s of kilometers from shore, placing an alligator 2 kilometers deep on the seafloor.

*The three alligators were culled by the state of Louisiana to control population numbers and in aid of restoration efforts. The alligator carcasses were then permitted to us for scientific use. The conservation and any taking of alligators in Louisiana is a very serious and thorough process. You can read more about the conservation success story that is alligators in Louisiana here https://t.co/LQskiPyg6e.

The post Alligators in the Abyss first appeared on Deep Sea News.

Nearly two miles below the ocean’s surface, we are building new worlds. You might be surprised that these ecospheres are wooden—little log cabins hosting a cornucopia of sea life.  By controlling the size of these wooden homes, we can begin to answer fundamental questions about how the oceans will adapt to climate change. In our most recent, paper we are beginning to grasp the extent that food controls biodiversity, biological novelty, and the competition among species.

On the seafloor, chunks of wood—we call them wood falls—play host to a variety of invertebrate species often not found anywhere else in the ocean.  These species live their entire lives on waterlogged timber; settling out of the water column as larvae to consume wood, or to prey upon other species that do.  Once on a wood fall, these organisms can never leave, their dispersal limited to the beginning of their lives as plankton. And for all of these reasons, the island communities created by wood falls serve as the perfect experiment.

Because of humans, the oceans are radically changing.  They’re becoming warmer, more acidic, and less oxygenated.  But an even more disturbing trend has been uncovered; the oceans may be becoming less productive, providing less food and carbon for its denizens.  Scientists do not really have a handle on how life in the oceans will react to this finding. What will happen to individual species and whole communities of species?  This is an intractable question in many ways because it is hard to test. We cannot easily experimentally adjust how much food a swath of ocean gets. Or can we? In a wood-fall experiment we can change the amount of food the community receives by simply adjusting the size of the log. These species cannot leave to look for better meals once they arrive.  They are wholly dependent on the log we’ve provided in an otherwise barren patch of the deep ocean floor.

In 2006, Jim Barry (MBARI) and I placed 16 logs with a remote operated vehicle (ROV) over 2 miles down on the deep-sea floor off the California coast. We left them there for five years and then remotely and robotically harvested them.  After sorting, identifying, and analyzing, these wood falls are revealing yet another fundamental insight.

How does more food, or more specifically more carbon, allow for more species?  To explain the science, let’s visit a donut shop. At this donut shop, there are three types of donuts: chocolate, plain glazed, and raspberry filled. I ask the donut maker to make three new donuts and provide extra ingredients for them to do so.  

In Scenario A, the donut maker produces chocolate, plain glazed, and raspberry filled along with a dark chocolate, a plain glazed with sprinkles, and a blueberry filled.  The donut shop is still just serving three basic types of donuts: chocolate, plain glazed, and fruit filled. These new donuts are just slight deviations. We will call this Scenario A donut packing.  The donut maker is just packing the menu with variants of the original donuts.

Much like donuts in a shop, we can think of species in a community the same way.  As food increases and the number of species increase, are we getting slight deviations (donut packing) or something truly novel (donut expansion)?  In the ecological sense, are niches, i.e. the full set of characteristics that describe a species and their requirements, being packed into the community or are we expanding the overall niche diversity.

And so for our wood-fall species, we put numbers to each of their niches describing their feeding habits, how well and even if they move, as well as their preference for space on the wood fall. We found that as you increase the wood-fall size, and the amount of wood, you do not get truly novel species, rather you pack these species into the community.  They are just slight deviations. This suggest that increased food reduces competition among animals allowing them to coexist peacefully. Species do not have to be completely novel to join the community.

In the end this means that decreases of productivity in the oceans, will limit diversity by not allowing species to coexist.  Species will be vying for the same spots and in the end many may lose.

McClain, C.R., C.L. Nunnally, A. Chapman, and J. Barry. (2018) Energetic Increases Lead to Niche Packing in Deep-Sea Wood Falls. Biology Letters 

The post Wooden Homes on the Seafloor Yield Insights Into the Impacts of Climate Change first appeared on Deep Sea News.

The Notorious B.I.G., Mase, and Puff Daddy understand. Increase one variable in a system and another variable rises en suite. For the B.I.G. this was money and problems. It’s like the more money we come across. The more problems we see. In the biological realm, increasing the food available increases the number of species. More food, more species.

In the case of B.I.G., Mase, and Puff how more money becomes more problems is clear. The trio “rock” and “sell out in the stores” which leads to more money. Bag a money much longer than yours. This leads to more purchases. Gotta call me on the yacht. The success and belongings are coveted by others who try to bring the trio down in an effort to elevate themselves. Know you’d rather see me die than to see me fly. But scientists are much less clear about how mo’ food leads to mo’ species. Scientists have erected dozens of hypotheses to explain this rather simple pattern.   Enter a deep-sea experiment that I dedicated 10 years of my life to.

Mo’ individuals, mo’ species hypothesis

Wright posed the more individuals hypothesis. The basic ideas is that low food supports smaller populations of species; any species is likely to be represented by just a few individuals. This makes these species more susceptible to being wiped out locally by a catastrophic event like a storm or predator. If in low food environments species are often going locally extinct, exacerbated by their low population numbers, then these environments are likely possess far less species overall. Wright’s hypothesis is ultimately a no food, mo’ problems, no species hypothesis.

Nothing-special hypothesis

Tilman, in one of the most influential papers in ecology, proposed the resource-ratio hypothesis. To simplify his elegant idea, few species are biologically equipped to deal with any resource at low availability. Mo’ food, mo’ species that can occur. Tilman actually proposed that species in resource-limited areas were just subsets of those living in high-resource areas. This is because any species can benefit with a little mo’ food, but conversely not every species can live with a little less. Tillman took these ideas a step further and actually predicted that at very high food availability the number of species should decrease because another resource would become limiting, i.e. high food habitats are not some beautiful utopia where everything, e.g. habitat space or other nutrients, is abundant.

The diva species/unique and special snowflake hypothesis

Of course this is not the real name of the hypothesis (none of the headings are). Several ecologists have converged on the idea that mo’ food allows for more specialized species. These diva species are very particular in their food type requirements. At low overall food availability, these specific food types are rare and cannot support a diva species. To restate, mo’ food allows species to be specialized. No food and species need to be generalists and take what they can get.

Mo’ food, mo’ prey hypothesis

Another ideas is that mo’ food allows for mo’ prey. This in turns supports mo’ types of predators, thereby increasing diversity. A more sophisticated variant of this is that mo’ complex food webs, containing mo’ species, can occur at higher food availabilities.

Mo’ food, mo’ giants and miniatures

This is a hypothesis of my own creation. Basically, there is “right” size for a given animal to be. This optimal size reflects a balancing of constraints. For example, too big and a species requires too much food. Too small and species does not have enough fat reserves to weather starvation. This suggests that areas with little food would only possess species of this intermediate and optimal size. Mo’ food and these caloric constraints are released and and species can get away with not being an optimal size. Thus both large- and small-sized species are allowed increasing diversity

Tourist hypothesis

Chase proposed another hypothesis that is fundamental to the mo’ food, mo’ species pattern; this pattern can only exist when low and high food habitats are isolated. If migration by adults or larvae can occur from high food to low food, diversity will be artificially elevated in low-food habitats. These tourist species from high-food areas cannot sustain themselves in low-food areas without consistent visits of individuals from these high food areas. Cut the flow of tourists and the diversity of low-food habitats diminishes.

Wood fall, the experiment

Scientists have published lots of creative studies testing aspects of these ideas. However, studies are rare that experimentally alter the food supply to a habitat and observe what happens. It’s not obvious how nor is it easy to increase the amount food at a coral reef or tropical rain forest. Mesocosm experiments, in which scientists creates an artificial system like a miniature ocean in a beaker or aquarium, provide exciting opportunities. My friend and colleague, Allen Hurlburt, conducted once such experiment in which he manipulated the amount of banana in containers.  Fruit flies collected in the rainforest where then allowed to colonize. It remains a beautiful and elegant experiment demonstrating the importance of food in controlling diversity. Allen’s study served as the inspiration for the wood-fall experiment.

Wood falls are the perfect experimental system to test mo’ food, mo’ species hypotheses. Each of the dead pieces of wood on the deep-sea floor represent little food islands. The background and typical deep-sea, muddy bottom is a food desert. The species occurring on wood falls are ultimately dependent on only the wood for nutrition. By ultimately controlling the size of the wood fall, we can control the amount of food the community of species receives.

In 2005, Jim Barry and I chunked 32 Acacia log into the deep ocean off the Central California coast. In actuality, we placed them with an ROV at spot over 3 kilometers deep.

Then we waited.

Five years later we collected half of the wood falls. Two years after that we returned for the other half.

Ten years after initially deploying the wood falls, the main paper from this work is now available as preprint. The nearly decade this experiment took to realize actually results in part reflected the length of the experiment.  However, even once collected a considerable amount of effort was need.  In the last three years, I spent countless hours meticulously sorting all the animals, nearly 13,000 individuals, from the wood falls. Taxonomists, all coauthors on the paper, spent many hours identifying these to species. With the analyses taken over a year plus the writing of the manuscript…well it adds up.

Wood fall, the results

Thankfully, with increased wood-fall size, i.e. increased food, the number of species actually increased. Strikingly, no individual hypothesis was the smoking gun for this increase in diversity.

Rather the mo’ food, mo’ species relationship reflects a combination of routes. In accordance with the mo’ individuals, mo’ species hypothesis, the total number of individuals increased with wood fall size, and was concordant with rises in the number of species. As predicted by the nothing-special hypothesis, the species on smaller wood falls, i.e. food poor, were just subsets of those species occurring on larger wood falls, i.e. mo’ food.   Increasing wood-fall size also lead to increased rare species, supporting the diva species/unique and special snowflake hypothesis. Increased larval connections between small and large wood falls also seemed to ameliorate the mo’ food, mo’ species relationship in conjunction with the tourist hypothesis.

I am just finishing examining body sizes of all the wood-fall species, but interestingly my pet hypothesis about miniatures and giants does not seem to hold. The pattern is far more interesting. Thanks to the many who supported my crowdfund project (I still love that video), David Honig and I are beginning to construct the food web through stable isotope analyses.

Notorious B.I.G., Mase, and Puff Daddy lamented the rise of problems with more money. However, to all three of these artists the reasons why this occurred were pretty straightforward. Haters gonna hate. People gonna covet your yacht. The biological world is much more complex. As simple as mo’ food, mo’ species is, the reasons why this elegant pattern exists represents a variety of interacting processes, only some we are beginning to understand.

McClain, C., Barry, J., Eernisse, D., Horton, T., Judge, J., Kakui, K., Mah, C., & Warén, A. (2015). Multiple Processes Generate Productivity-Diversity Relationships in Experimental Wood-Fall Communities Ecology DOI: 10.1890/15-1669.1

The post More Food, More Species first appeared on Deep Sea News.

When I crowd funded part of my wood fall research, Immy Smith reached out to me about painting some of the life that occurs on these unique habitats.

Immy Smith is an interdisciplinary artist, interested in biological and surreal imagery. She is currently a visiting artist at Herbarium RNG. Immy combines textural graphite drawing, painting and collage, with colourful images from natural history. In storytelling through art, she pools peculiar combinations of objects and associations of form. Immy previously worked investigating how potential plant-derived medicines affect isolated human brain cells, and she is heavily influenced by exploring the biology behind shape and function of cells and organisms. With her PhD in pharmacology, Immy considers her scientific and artistic practices to be integrated with each other; making art is an experiment, and scientific research can only be developed with imagination. Art can ask open-ended subjective questions about how we relate to science and our environment; therefore art and science allow us to explore our world more fully and imaginatively when applied together.

Immy just recently sent me the artwork she created and gave me permission to share it with DSN readers. Please go check out her website for more wonderful works.

The post Beautiful Wood Fall Art from Immy Smith first appeared on Deep Sea News.

Keep this basic fact in mind as you consider that carbon production on land and in the oceans is radically shifting as our climate changes.  At least one study indicates that the global production of phytoplankton, the basis of the ocean’s food chain, is declining.  But the global pattern is more complex than that. The equatorial Pacific experienced overall declines of ∼50% over the last decade while polar regions experienced comparable increases. Clearly, we need a more complete understanding of the consequences of current and forthcoming climate change as it impacts the ocean’s food supply.

Research on both the species and habitats on land have provided us with some evidence of what might occur in the oceans.  As food increases, you expect there to be more life.  Animals should be more abundant and larger in size.  As food decreases, you should expect the opposite.  Yet, we do not know if energy is equitable distributed.  Do all species get equally larger and more abundant? Some species may be able to monopolize the food.  For example, prior research, mine included, suggests that certain sizes, especially the medium sizes, dominate the energy demand.   However whether this remains constant at both high and low food availabilities is unknown.

Food webs are also predicted to become more complex with increased energy. High food availability at the base of the food chain allows more energy to reach the top.  Thus more energy supports a greater diversity of top predators.  However, the differences in the body sizes of the prey and predators can turn this simple relationship on its head.

Increases in the number of different species might occur with increased food this is referred to as the species-energy rule.   More energy allows species to have a higher abundance.  This larger population is buffered against random detrimental events and less likely to go locally extinct.  Thereby more species would occur in the local community.  Alternatively, additional energy may elevate rare kinds of food, allowing rare species eating these rare foods to exist.  And given more energy, diversity may increase because those top predators are being supported.  These are just three of nearly a dozen different hypotheses relating food availability to biodiversity.  But lots of food may also lead to an alternative outcome where a superior competitor consumes all the food. Thus diversity may actually not change or even decline with more food.

I could spend the rest of this post writing about all the different theories and ways that a community of organisms could be impacted by changes in food.  However, it would remain just that, theory.  What we lack, especially for the oceans, is real data.  But studying the impacts of changing energy on a real community of species is difficult if not impossible.  One, we often lack knowledge of the total amount and source of energy in a habitat.  Two, it can be impossible trying to experimentally manipulate it.  How would you easily change the amount of food available in a forest?

This is where the wood fall project comes into the play. In 2006, Jim Barry (Monterey Bay Aquarium Research, MBARI) and I (when I was a MBARI postdoctoral fellow with Jim) chunked 36 logs into the deep to begin the examination of wood fall communities. The wood varied in size from 1.4 to 45.4 pounds.  The species that occur on the wood fall are completely reliant on the wood for food.  Indeed, wood falls are like little energetic islands.  They represent carbon availability 100-1000x greater than the surrounding deep-sea mud.  Wood falls are an oasis in a food desert.   With wood falls we know exactly where the energy originates and we can control the total amount of energy available to the community. In addition, we are able to track the flow of energy through the wood fall food web chemically using the unique carbon signature of the wood itself.

Wood falls are the best model system for understanding exactly how life is influenced by changes in energy. Wood falls are a window into how the oceans will respond to climate change.

We have just started analyzing the retrieved logs and our first paper is now in review!  The next step is to build the food web and look for the unique chemical thumbprint. These analyses cost anywhere from $10-$20 per sample and for an accurate assessment, we need dozens of individuals from the multitudes of species on the wood fall.

This important project opens a direct window into our ocean’s response to climate change. We need your help to make it happen. We’re a third of the way to our funding goal $4,000, but if we don’t make our goal by March 7^th, we don’t receive a penny of the funds. Please support our project with a donation today.  

https://experiment.com/projects/wood-is-it-what-s-for-dinner

The post Wood falls are an oasis in a food desert first appeared on Deep Sea News.

I am participating in this round of the Scifund Challenge with my project Wood: Is it What’s For Dinner?  The project seeks funding to examine the stable isotopes of animals on wood falls. By examining these chemical fingerprints we can determine what each animal eats and whether it is predator or prey.  This will yield a richer understanding of how land and oceans are linked in the global carbon cycle.  

I need your help to fund this research!  My ultimate goal is to raise $4,000 but I know you can help me raise even more!  Want to contribute to the project and get a little wood fall and DSN sway as well?  You know you do!

The link is real easy to remember and hand out to all your friends tinyurl.com/gotwoodfall

Below I describe more of the project but instead YOU MUST WATCH THE VIDEO BELOW about the project.  The video is the brain child of myself, Alex Warneke, and Sarah Keartes.  Alex was the creative director and Sarah the producer.  What you get is amazing dub step from Medium Troy (on Sound Cloud) mixed with sweet wood fall footage from MBARI’s ROV Doc Ricketts.  Special thanks to MBARI for the footage!

What’s This Research All About?

The Secret Oceanic Life of Tree

Each day a tree dies. Its carcass may lay there on the forest floor, ravaged by fungus, insects, and plants as they grow from its remains. But, perhaps the tree meets a watery grave–gently floating down river ultimately finding itself bobbing in the ebb and flow of the tides. Eventually this tree becomes waterlogged and begins sinking.

At a critical depth and pressure the ocean squeezes the last bit of terrestrial air out of the wood replacing it with brine. So begins the story with a tree sinking into the deep. Wood falls range from small fragments to 2000+ pound behemoths. In the deep, devoid of light and plants, a wood carcass brings a rare commodity—food. The amount of carbon a tree or piece of wood brings to the seafloor can be anywhere from ten to a thousand times that regularly encountered on the seafloor. From the carcass comes nourishment to sustain deep-sea life.

Ocean Creatures Eat Snacks From Land

What’s surprising given the rarity and uncertainty of that wooden treat along the deep-sea floor, is that wood falls possess a fauna wholly specialized for living and consuming them. The digestion of a fibrous and solid food source requires talent, a hearty gut, and some bacterial help–traits not many species possess. These organisms finish the tree off, tearing it apart from inside and out. Bivalves of the genus Xylophaga (measuring less than an inch) use a ridged shell to bore into the wood, ingesting the wood fragments. On their gills they host an endosymbiotic bacteria that can digest their woody snack. But, something extraordinary also happens on wood falls, special bacteria anaerobically breakdown the wood. One of the by-products of this, sulfide, can be used by chemosynthetic bacteria, similar those at hydrothermal vents. These bacteria provide a tasty snack for animals at wood fall. Scientists know little of which species gain nutrition through a pure wood versus the sulfur route. Nor do we know which species are preying upon others. Using the chemistry of the animals, by looking at stable isotopes of carbon, nitrogen, and sulfur, we can begin to reveal this.

Understanding Food Webs with Stable Isotopes

Carbon, nitrogen and sulfur are all important elements obtained from eating other stuff. The old adage “you are what you eat” is actually true to some extent. Each animal has a slightly different signature of stable isotope ratios that reflect the signature of preferred food items. In nature, 1.1% of all carbon isotopes are the stable Carbon-13. However, plants and phytoplankton take up Carbon-13 differentially; Carbon-13 serves as sort of a chemical thumbprint of the food source. Terrestrial plants possess higher values than phytoplankton which in turn are higher than seagrass. The nitrogen isotopes, specifically Nitrogen-15, how high up the food chain an animal is. As organism eat each other, Nitrogen-15 is transferred to the predator. Thus, top predators have the highest Nitrogen-15 values. Looking at the Sulfur-34 concentrations can tell us whether an animal is munching on the sulfidic bacteria or predator of something that does.

Chunking Wood Into the Ocean: The Experiment!

In 2006, Jim Barry (Monterey Bay Aquarium) and I chunked 36 logs overboard to begin to examine wood fall communities. Chunked may be a strong verb for sending them down on a benthic elevator. Once on the bottom, a remotely operated vehicle dispersed them over a 1600 square foot area now affectionately referred to as Deadwood. In 2011 and 2013, we retrieved these wood falls. On the surface, I and others picked through the once solid but now bore-riddled and crumbling logs for Xylophaga, limpets, worms, snails, and other wee beasties. As we picked through the rotting wood carcasses, my level of excitement was only matched by the sulfidic, rotten egg, stench of decomposition.

Why Should I Care About This Research?

Wood represents a significant source of carbon input into the deep oceans and ties oceans and land together in the carbon cycle. Wood has been found frequently on the deep-sea floor several miles deep and several miles from land. During major storms that drive erosion and move debris down river, the movement of wood into the oceans can be sizable. During the Typhoon Morakot in 2009, the total amount wood weight carried to the oceans was estimated to be the equivalent weight of ~850,000 school buses. On the deep-sea floor, a single wood fall can enrich the carbon of the sediment by >25% even after several years. This represents a major pathway of natural carbon sequestration that has received little attention. We know very little of the fate of this wood based carbon after it arrives to the seafloor.

But this forest to deep ocean carbon pathway may be changing owing due to deforestation and increasing river discharge. From 2000 to 2005, 7.3 million hectares of forest per year were lost. In most of insular Southeast Asia, the forest cover decrease exceeds 50% and is well over 80% in New Guinea. Across Mexico, only 27% of the original forest cover remained intact by 1990. In addition, global warming is driving greater transport of atmospheric moisture in certain areas leading to increasing river flows. From 1936-1999 annual discharge of water in the largest Eurasian rivers into the Arctic Ocean increased by 7%.

What Are We Actually Going to Do

In collaboration with Jim Barry (MBARI) and David Honig (Duke University) and using specimens collected from the Deadwood experiment

1. We aim to analyze stable isotope compositions (carbon, nitrogen, and sulfur) of at least ten individuals of each species.
2. By conducting a statistical analysis on the isotope data, we will construct the food web of a wood fall community.

The post Wood Falls, Chemicals, & Dubstep first appeared on Deep Sea News.

• A Lonely Tree Far From Home Brings New Life to the Ocean Deep: A Narrative in Five Acts @DSN
• Some Echinoderms Will Never Grow Up @DSN
• Wood, It’s What’s For Dinner  @DSN
• Wood from Land Feeds Deep Sea Life @DSN
• I Got Wood @DSN
• Making science out of chucking stuff in the sea @Eclectic Limpet
• Why land plants matter to deep-sea critters @Eclectic Limpet

Not to board you with more but below is a gallery of images that I think will spruce up the post.   The photos are from wood falls nearly two miles deep on the Pacific seafloor and many are courtesy of the Monterey Bay Aquarium Research Institute.  I hope I left you pining for more.

The post Will My Wood Research Be Poplar? first appeared on Deep Sea News.

A deep-sea crab walks into a pub and asked, “Where’s the bar tender?”

Few deep-sea organisms rely on food originally from land.  Most deep-sea dwellers rely on  marine snow (detritus raining from the surface), large food falls like dead whales, or chemosynthetic pathways like those at hot vents and cold seeps.  This makes sense.  How much land plant material makes into the deep sea?

Apparently enough to make a living on.  When chunks of wood make it to the seafloor, they form specialized communities, i.e. wood-fall communities.  As the wood degrades, bacterial mats form, clams bore into it, and a host of other organisms come in to feed.  New work in Marine Biology suggests that the most dominant group after mollusks, the crustaceans, may also be feeding on the wood.  Researchers found wood in the gut of Munidopsis andamanica, a squat lobster commonly found at woodfalls.  Further work indicates that a resident gut microflora of bacteria and fungi exist that may aid in digesting wood fragments.  However to eat wood a species is going to need a robust digestive system.  Roughage, indeed!  Detailed anatomical analysis revealed that the mouthparts and gastric mill, i.e. stomach, were modified to be stout enough for a lumber diet.  The claw is also spoon shaped and thought to serve as a utensil to bring wood bits to the mouth.

M. andamanica thus represents another  pathway by which carbon cycles derived on land cycles into the deep sea.

Hoyoux, C., Zbinden, M., Samadi, S., Gaill, F., & Compère, P. (2009). Wood-based diet and gut microflora of a galatheid crab associated with Pacific deep-sea wood falls Marine Biology, 156 (12), 2421-2439 DOI: 10.1007/s00227-009-1266-2

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