Blog post by Jean-Olivier Irisson
Blog post by Jean-Olivier Irisson
Hey plankton hunters! We are bringing you another round of Fantastic Finds from the Plankton Portal. Citizen scientists continue to reel in new captures of some truly awesome plankton. Here are just a few neat finds, ID’s, and novel taxa:
Did you ever learn about marine butterflies in grade-school? Well good, because there is no such thing as a marine butterfly. This elegant-looking critter is a pteropod, a type of gastropod mollusk—in other words, a slug! These mollusks are highly adapted for life in the water-column, as you can see from the butterfly-like wings, (or “parapodia” to a malacologist). The pteropod wings are actually a highly-modified molluskan foot, i.e. the muscular and slime-secreting mass that slugs glide on. Evolution really did these slugs a favor, as I do not think anyone could say “ewww!” to such a beautiful animal.
Now this is a fantastic image. A close-up, finely-detailed capture of the head (nectosome) portion of a calycophoran siphonophore—so aptly referred to as a “rocket-ship sipho” here on the Plankton Portal. The two siphon-like features propelling this colonial critter are very apparent in this image. Maybe, in truth, siphon-ophore is a pretty apt name for this plankter as well.
Ctenophore: Thalassocalyce inconstans
Thalassocalyce inconstans is a predatory species of ctenophore, captured feeding in this frame. The body of the ctenophore is contracted and engorged about the anteroposterior (vertical) axis, giving it the appearance of an inflated, heart-shaped balloon. Within the fragile and transparent body, you can see the 8 condensed comb rows captured as an array of ragged segments crowning the aboral end. Fine mesenterial canals also appear as contoured markings that line the engorged body. Ctenophores are tactile predators, meaning all predatory behavior is triggered by physical, non-visual stimulus. Something in the water column bumped into this Thalasso and got it all riled up, providing ISIIS a great opportunity for this detailed capture of foraging behavior. If we had a hydrophone for this deployment, I am fairly certain a satisfied lip-smacking would be recorded in a few seconds.
Copepods: Families Eucalanidae and Metridinidae.
Copepods are abundant in these ISIIS data, and it is easy to forget what a broad diversity of these important crustaceans are classified on the site. Here we have two broadly identifiable PP copepods for sample. The image on the left shows a copepod belonging to the family Eucalinidae: it has a narrow, torpedo-shaped body and the anterior end of the head forms a pointed-triangle. We think this critter might be a Rhincalanus spp.—if you look close you might be able to make out a small rostrum-like appendage extending forward and tucked down from the head, as well as what may be lateral spination at the end of each mid-body segment (prosome). This guy’s cruising, antennas spread out and scanning the surroundings. On the right, we have a copepod belonging to the family Metridinidae, perfectly poised for the ISIIS cam. How do we guess this ID? At the end of this copepods lengthy tail (urosome), look closely at the paired fin-like feature (ferka). Along the outer edge, right before the separation of the individual ferka, can you make out a small, skirt-like protrusion? If so, just tell your buddies: “hmm, check out that lengthy urosome and ferka segmentation; it must be a Metrinidae species,” and blamo—you are a crustacean taxonomist!
Anthomedusae: Leukartia spp.
At first glance, you might be thinking “is this medusae sticking its tongue out at me?” Or maybe it is sporting a ten-gallon hat? While I couldn’t blame you for such outlandish assertions (I mean, who would write such silly things?), this odd anthomedusae is readily identified to genus by the conical appendage extending from the bell (“apical process”) and causing much confusion on the Plankton Portal. In this image we get a great view of many internal and external features of this Leukartia sp., including a crenulated (ragged) bell margin, a tall mouth (“manubrium”) in the center of the bell, and many long tentacles projected both downwards and in front of the bell.
Larvacean and mucous house
We find a good deal of larvaceans on the site, but this capture is a real beauty. Larvaceans are gelatinous plankton that filter-feed on detritus in the water column. You see the critter poking its head out, like the cap on a rolled-up toothpaste tube? That’s the larvacean, curled up in preparation to pump surrounding detritus through its elaborate mesh-like mucous house. For a critter that takes up residency in its own secretion, this guy is pretty adorable!
Now this is quite the fantastic find! Here we are looking at a large siphonophore projecting numerous tentacles across the frame. It is all-hands-on-deck for this colonial jelly, as it is putting on a mighty foraging display for us. The big guy is hungry—watch out, ISIIS.
There have been way too many great images to fit in this small serving of photogenic plankton. We look forward to serving up more fantastic finds in the future. Keep exploring, plankton hunters!
There is a new dataset on PlanktonPortal!
In summer 2013, a group from the original science team behind PlanktonPortal (Bob Cowen, Cédric Guigand, and Jessica Luo) teamed up with French colleagues (Jean-Olivier Irisson, Robin Faillettaz and other members of the Laboratoire d’Océanographie de Villefranche) through a Partner University Fund-sponsored project. We roamed the Mediterranean sea, equipped with ISIIS, the instrument which takes the images seen on PlanktonPortal, and a collection of other sensors. Our aim was to understand how physical discontinuities in the ocean (such as the strong coastal current along the French Riviera) influence the plankton. These discontinuities often create conditions in which plankton thrives and this has important consequences down the rest of the food chain.
After a rocky start (see our project blog), we eventually managed to get almost five full days of sampling. Five days; it seems short. And ISIIS was actually acquiring data of scientific interest during only 93 h within those five days. That is 3.8 full days, which seems even shorter. But that amounts to about 17.5TB of data (terabytes, as in 1024 gigabytes). In terms of images, that represents 19 trillion pixels, which could be divided into 34 million PlanktonPortal frames. So, clearly, we need your help!
We actually spent much of the last two years processing the images and classifying organisms in a small fraction of them, to be able to filter out most frames with no organisms using computer algorithms. Now we are ready. Ready with a few hundred thousands frames from the last two days of the cruise that no one has seen before and in which you can help us identify plankton.
Hi Plankton Portal!
The Science Team is currently out in the field in the Straits of Florida, on the R/V Walton Smith, sampling with both ISIIS and MOCNESS (Multiple Opening Closing Net and Environmental Sampling System), on an 18-day cruise titled OSTRICH (Observations on Subtropical TRophodynamics of ICHthyoplankton).
The overall goal of this NSF-sponsored project is to quantify the patterns and consequences of the fine-scale to sub-mesoscale distributions of larval fishes, their prey, and their predators near and across a major western boundary current passing through the Straits of Florida. By sampling a series of water masses at very high resolution, this study addresses specific hypotheses concerning: i) the drivers of aggregations and patchiness, and ii) the biological consequences of predator-prey interactions at fine scales.
Sampling involves a novel combination of detailed in situ sampling of the horizontal and vertical distributions of plankton, targeted fine-scale net sampling, and analyses of individual-level recent daily larval growth to enable the identification of the biological and physical processes driving fine-scale plankton distributions.
Follow along on the ISIIS facebook page as we periodically post updates (via our terrible internet connection at sea!) and also check out this cool video made by one of our cruise participants, Chris Muiña:
Hello everyone. We have a special “behavior” Fantastic Finds Friday (FFF) today! These frames were selected from your posts to illustrate the power of the human eye to detect rare and unusual phenomena. The frames selected here may not be the most beautiful you have seen so far, but the story behind them is fascinating and could not be told without the help of our citizen scientists.
Here is great shot of a larvacean (also known as an appendicularian) getting spooked by the movement of ISIIS. Larvaceans are known to escape from their mucous house if threatened by a predator. Unfortunately the house can’t be used again, and they will start secreting a new house once the threat is passed.
Arrow worms (chaetognath) are voracious predators capable of engulfing prey as big as their own body. In these images, you can see an arrow worm catching a larvacean and the other grasping what appears to be a copepod. Their mouths resemble a crown of spikes ready to impale any unlucky prey. Chaetognaths also prey on fish larvae.
These two medusae just snagged a larvacean house. Accident or deliberate attempt to feed on these poor guys? The long trailing tentacles act like a sticky fishing net that retracts to bring in the catch of the day.
These Solmaris seem to be reaching for something (one tentacle pointed opposite to the others). Solmaris have been seen feeding on other jellies – even large siphonophores! They swim with their tentacles forward to maximize the chances of catching a prey. they then move the item to their mouth with one tentacle (like an arm almost).
No, these are really two different frames! Amazing consistency in posture isn’t it? And look at these two tentacles reaching out – sensing their environment? Hoping to encounter a tasty prey item? If we detect enough of these organisms, we could try to investigate at which time or location they behave this way. This could be a really interesting project!
So if you see something interesting like these example or suspect some interaction is at play in one of the frame use the hashtag #behavior. Remember to mark frames you want considered for future Fantastic Finds Friday posts with #FFF. Thanks, and keep up the good work!
Greetings plankton enthusiasts, new and old! My name is Jenna Binstein and I recently graduated from undergrad at the University of Miami. I enjoyed my time there so much though, that I signed on for another year as a graduate student! Part of what made my undergraduate years so fulfilling and worthwhile was my work in the lab with Dr. Cowen, Jessica, and the rest of the ISIIS/plankton team. Before I go into more detail about my work there, let’s take a quick look at how I found my way into the marine sciences.
It all started when I got my SCUBA certification as a freshman in high school. After my first open water dive I was hooked. I knew I had to learn all there was to know about marine science. At first, I thought I wanted to study the “big” stuff: dolphins, sharks, or turtles. I had seen jellyfish on SCUBA dives before, but I always considered them pests. I never thought as I applied and enrolled at UM that I would find such passion in studying some of the smallest organisms in the ocean, and learn just how important and collectively “big” they actually are.
Basically, my journey with plankton started when I met Jessica and Adam and began helping them with their respective dissertation research. I started learning to identify zooplankton, just as you all are learning to do via Plankton Portal! I started getting comfortable with the images from ISIIS, and eventually began to develop my own interest and senior thesis project with mentorship from Jessica. I decided to begin looking more closely at Appendicularians. Very little is known about these guys and their unusual mucous housing. So I spent a long time quantifying Appendiularians by size, classification, and whether or not they were inside a mucous housing when I saw them. The goal was to be able to identify an existing relationship between depth and whether or not an Appendicularian was found in its housing. I briefly looked at other factors as well, such as frontal dynamics, size, and classification and then saw if these related to an Appendicularian being in or out of its house. Although I completed my senior thesis, the work is not over; as there is still so much more I can pull from the data! Yet overall, I learned so much about Appendicularians and their role in the oceans, and I will definitely share as much of that as I can with all of you on some later blog posts relating specifically to the Appendicularian. In the meantime, I hope to continue learning all I can about Appendicularians and other gelatinous zooplankton during my time with the help of ISIIS, Plankton Portal, and UM.
Until my next post, happy jellyfishing everyone ≡≡D
Jenna Binstein, B.S.M.A.S., is a student in the Masters of Professional Science program at the Rosenstiel School of Marine and Atmospheric Sciences (RMSAS), University of Miami. You can reach her at jbinstein [at] rsmas.miami.edu.
Hey plankton hunters! Welcome to our 3rd round of Fantastic Find Friday here at Plankton Portal. There have been so many awesome finds on the site and we picked 5 this week for you to check out. If you see something really neat on the portal than tag it with #FFF so we can check it out for use on the blog. Here we go!
Physonect Siphonophore— #Sipho #Corncob
This is a stunning capture of a physonect siphonophore who seems to be waving hello to ISIIS as she passes by. Like all siphonophores, this guy here is a colonial organism comprised of many individual animals or ‘zooids.’ Each zooid is specialized and distinct, but work together so closely that they more resemble a single organism than a colony of animals. On display here are the branching tentacles used for foraging and the swimming bells that resemble a corncob. This one is a stunner!
Lobate Ctenophore — #Lobate
This is a really neat capture of a lobate ctenophore (Ocyropsis maculata), showing off the feature that gives this guy his name. In this image you can see clearly the internal structure and the striated texture of his muscular, gelatinous body. Lobate ctenophores swim lobes forwards by beating the ciliated comb rows situated on the opposite (aboral) end. The one depicted here would be swimming towards us and to the left. I wonder if larvacean is on the menu?
Chaetognath — #Arrowworm
Looks like an arrow shot by some undersea archer, right? Arrow worms, or chaetognaths, are carnivorous marine worms belonging to the Phylum Chaetognatha. They are notoriously ferocious predators that hunt other plankton with the help of hooked ‘grasping spines’ that flank the mouth. Chaetognaths have fins for propulsion and steering—you can see all of them really well in this capture! While these fins superficially resemble those of a fish, they are not related evolutionary and are structurally very different.
Calycophoran Siphonophore — #Rocketship #Triangle
I bet NASA would get a lot more funding if they built space shuttles that looked like this! This beautiful capture of a siphonophore really looks to me like some sci-fi monster a (horrified) astronomer might see in a telescope! Don’t worry though, this guy is just a couple of cm’s long and probably couldn’t hurt you if he tried. Just like the physonect siphonophore above, this guy is a colonial organism and would therefore be more appropriately referred to as guys. The tail, or stem, on display here contains two developmental stages of siphonophore simultaneously—both the medusa and polyp stages. Unlike most cnidarians that alternate between these stages generationally, this guy chooses to have them coexist within the same colony. If you look closely you can see them bickering over who is the prettiest!
Calanoid Copepod — #Copepod
This copepod is making a heart with his antennae! Do you think he might be in love? There is some 13,000 species of copepod in the world and they are a crucial component of plankton communities and global ecology in general. It has been suggested that copepods may comprise the largest animal biomass on the planet! Many species of marine life, large and small, rely on these guys as their main food source, including whales and seabirds. Looks like this guy here is a lover not a fighter!
Looking forward to next time !
The underlying objective of this research project is centered on a small-scale front and its associated biological activity. A front is a meeting of two water masses, and oceanic fronts are generally broken up into several broad categories, depending on the physical environment and phenomenon that cause these water masses to converge. Oceanographers have been interested in fronts for a long time, because they tend to be areas of high productivity. The elevated productivity at fronts is a result of the converging water masses physically aggregating many marine organisms.
Small-scale fronts are, as the name suggests, smaller in spatial scale: they tend to occur on the order of tens of kilometers instead of hundreds to thousands of kilometers like some of the other major fronts. Small-scale fronts occur frequently, but have also been harder to describe because they are more ephemeral than large fronts.
We set out to study one particular small-scale front in the Southern California Bight (SCB, see map for study region) because it was in an area that has received long-term oceanographic investigation – it is always good to do studies where there is lots of baseline data. We were primarily interested in exploring what biota was out there and seeing if there was biological aggregation at the front. Indeed there was! We saw a large aggregation of our now favorite jellyfish, Solmaris rhodoloma, at the front and described it in a 2012 research paper. You don’t have to worry about reading it. It basically says what I just told you: we found a lot of Solmaris at this small-scale, salinity-driven front.
One of the interesting things about Solmaris is that they are part of a family of medusae that predate exclusively on other gelatinous zooplankton. They have been known to eat arrow worms and doliolids, but now, because of our images, we also think they are eating larvaceans and small siphonophores as well. So finding the large aggregation of Solmaris actually generated another research question for us: what’s going on with the rest of the gelatinous zooplankton at and around this front? What are the main processes driving their distribution? Is predation pressure from Solmaris affecting them in any way?
It turns out that the second question is much harder to answer than you would think. Not knowing exactly what Solmaris is eating, and how long they’ve been accumulating at the front makes it difficult for us to tell if they’re just happening upon a patch of prey or they have already eaten everything around them. One approach is to determine the movements and directions of the organisms, which is why we’re asking you to measure their orientation. We hope that knowing their orientation (and that of their potential prey) can help us model their movement patterns and “age” the Solmaris aggregation, so to speak. Of course, it’s possible that even with this data we will still not be able to determine how long Solmaris has been aggregating at the front. However, this kind of orientation information has never been acquired for jellyfish of this size and at this scale, so any data we gather will be new and interesting!
This is just one of many questions that Plankton Portal can help answer. The biological data contained within these images can bring us closer to a greater understanding of zooplankton ecology in general. Understanding the abundance, distribution and biomass (that’s where the size measurements come in) of this extremely understudied group of organisms – the small gelatinous zooplankton – can help us assess their broader impact in the marine food web, contribution to carbon cycling, and even help us learn how to identify hotspots of marine productivity in the future. This is how research grows and develops: it starts from a small, initial question (“hmm, I wonder if there is anything interesting at a small offshore front?”), which leads us to additional questions, and down the road, will hopefully help mankind appreciate and better protect its precious marine resources.
Thank you for your help and participation in Plankton Portal – you are contributing to a more knowledgeable future and hopefully one where we can better care for the sea around us.
We are at the end of week 2 and we pulled out some of the best finds from this past week. As a reminder, every Friday we will post a selection of Fantastic Finds. If you think you have found something really great on Plankton Portal then tag #FFF and we will check it out for use on the blog. Thanks for tagging your favorites this week!
Larval fish are actually considered part of the plankton, as fish in their early life stages will drift along in the oceanic environment. Because larval fish are relatively poor swimmers, they are under high predation pressure and more than 99% of baby fish that hatch from eggs will not make it! It’s a tough life. You might not know it from this site, but studying larval fish is a major component of our lab. Dr. Cowen has spent his career studying larval fish, their distributions, dispersal and population connectivity. In this particular study, we did not sample very many larval fish so we did not include it as one of the categories. However, we are incredibly interested whenever we see one so definitely tag the fish in the forum when you see any! #Larval #fish
Liriope tetraphylla (#Medusae #4tentacles) with Arrow worm
This is one of my favorite pictures from this week because what you see Liriope tetraphylla actually eating the arrow worm! Here one of his tentacles has brought up the arrow worm into the gastric peduncle (that’s the long thin appendage in the middle of the umbrella that looks like a handle). He appears to be holding the arrow worm in place while he eats his dinner. As far as I know, the only scientific study of what Liriope eats is from a paper by Larry Madin in 1988, published in the Bulletin of Marine Science, where he found that Liriope eats larvaceans, crustacean larvae, heteropods and juvenile fish. No one has reported that Liriope also eats arrow worms … until now.
Sphaeronectes koellikeri – #rocketship #thimble
This beautiful creature falls within the broad group of jellyfish-relatives called the Siphonophores. Here you see this animal in a stunning feeding display. Though these guys are small and relatively inconspicuous, other siphonophores can get up to hundreds of feet long, and as a group are considered the deadliest predators in the ocean. One fun fact: these rocketship siphonophores grow from the base of the stem towards the tail end. So the tail end of the stem is one of the oldest parts of the body. Sometimes you’ll even see small rocketships budding from the tail!
Radiolarian colony – #radiolarian #colony
We know that you’ve been frustrated by those small fuzzy round objects that invite classification but really aren’t supposed to be classified. Those are protists, a diverse group of eukaryotic microorganisms. One type of protist is the radiolarian, which are known for their glass-like exoskeleton, or “tests.” They are incredibly important in marine science because their tests are made of silica, which are preserved in marine sediments after they die and sink to the bottom of the ocean, and provide a record for paleo-oceanographic conditions, such as temperature, water circulation, and overall climate.
Radiolarians also form colonies. Colonial radiolarians are interesting because first, little is known about them, despite their abundance in the open ocean, and secondly, they are hosts to symbiotic algae that are modest but significant primary producers in the ocean. It has also been suggested that we are vastly underestimating the abundance of radiolarian colonies. Since primary production (photosynthesis, the conversion of sun energy into carbon) is the basis upon which all ocean life can exist, it’s incredibly important to understand who all the different primary producers are and how many of them are out there!
That’s all, folks. Thanks for reading, thanks for classifying, and remember: mark your favorites with #FFF for next week’s Fantastic Finds Friday!
In many fields of science, new technology is leading to unprecedented data production. This, in turn, requires extensive analysis with minimal sub-sampling to detect as much detail as possible. In biological oceanography, imaging systems have become more useful with increasing computer speed and storage capabilities, and image data address some of the fundamental problems with traditional sampling methods that are destructive to fragile organisms (i.e., jellyfish and marine snow). On a given tow with our system, the In Situ Ichthyoplankton Imaging System (ISIIS), we produce approximately 400,000 images in 7 hours with many different species across a range of sizes present in each image (500 μm to 13 cm). This is an incredible amount of information that would take years for one person to fully analyze. When we are out at sea, we typically sample for WEEKS and come back to land with millions of images. Computer algorithms can perform basic tasks of extracting specimens that look similar, but human brains are extremely adept at interpreting an organism in 3D and providing context in the image data that a computer cannot. The amazing abilities of people to recognize patterns that computer algorithms may see as unimportant cannot be underestimated.
Another reason we are using Citizen Science is so that you, the citizen scientist, can participate in the process of discovery. After all, most oceanographic research is funded at least in part by taxpayer money, and these novel plankton images combined with Citizen Science are a great way to engage those who fund the research. We think it is far more effective to cultivate interest in science through the discovery process itself, rather than the production of jargon-filled reports and papers only understood by other oceanographers (don’t worry, those will come later). In addition, this online format provides an opportunity for us to educate people about life in the oceans, potentially inspiring the next generation of ocean scientists. With Citizen Science, there is the potential for new discoveries arising from simply allowing many people to look at the images.
We believe our research with ISIIS is particularly applicable to Citizen Science and the process of discovery because this new imaging technology provides a huge amount of data and a unique glimpse into ocean life. I have spent the last 5 years of my graduate school career at the University of Miami examining hundreds of thousands of plankton images, and every time I flip through the images, I always have the feeling that I could see something that no human has ever seen before. I try to instill this sense of wonder and hope for discovery in all people that work with the images, because when you see something interesting, like an elaborate siphonophore or a dense patch of copepods, you are likely the first person to see that species in its natural environment. When we get enough eyes on these images and discussions facilitated through the Plankton Portal website, the sky’s the limit for the discoveries that can be made with Citizen Science!