Iceland Scallop

Time to celebrate the funding of Mrs. M.'s project, Coral Reef Flip Books, part of the Ocean Bloggers Oceans in the Classroom Initiative. Yesterday I asked for input on which card to feature, and the results are in: with 33.33% of the "vote" the Scallop of Hearts gets the next preview here. I should note that the picture on this card is likely to change before the final version, when we hopefully will get an image of a live animal without too many epibionts (organisms that live on the surface of another living organism, generally a commensal relationship) on the valves.

Classification for the Icelandic Scallop

Kingdom

Animalia

Phylum

Mollusca

Class

Bivalvia

Order

Ostreoida

Family

Pectinidae

Genus

Chlamys

Species

C. islandica

Range

It is thought that the Chlamys genus originated in the Pacific and expanded into the Atlantic. Fossil Chlamys shells have been found dating to the Miocene in California. In the Atlantic ocean fossilized shells of the Icelandic scallop (Chlamys islandica) have been found from the late Pliestocene, when it ranged as far south as Long Island in the west Atlantic and to the Mediterranean in the east. Today it is found from Hudson Bay to Cape Cod in the western Atlantic and along the coast of Norway in the eastern Atlantic. It is also found in the fjords and waters of western Greenland and Iceland.

The Iceland Scallop (C. islandica) is the northernmost occurring of the major commercial species in the Pectinidae family, occurring in sub-arctic waters of the Atlantic. Several similar species, once thought to be subspecies of C. islandica, are found in similar areas of the sub-polar Pacific. In many areas of C. islandica's range, it is, or has been, a major fishery species. In recent years however in much of its range the fisheries have collapsed.

Fisheries

In most of Norway the fishery for the Icelandic scallop suffered complete collapse in just three seasons and has only recovered in one location. In Iceland the stock is (as of 2008) only at 13% or less of its size just one decade earlier. The causes of the rapid decline in Iceland have been investigated by several researchers. They have determined that overfishing has had a strong impact on the stocks, but the effect has been magnified because of two environmental factors. A protozoan parasite is affecting large numbers of adults, causing increased adult mortality. Sea bottom water temperatures have increased more than 2°C, possibly contributing to both adult mortality and very poor juvenile recruiting years for the past four years, take a moment to think of the implications of climate change for this species. Because of all this, the fishery was recommended for closure in the 2009 and 2010 seasons.

North American stocks have not fared much better in recent years, with strong declines in stocks. The sharp stock declines worldwide coupled with the fact that they are only wild-fished using dredges, which extensively alter the hard bottom habitats where they live, have caused organizations, such as the Blue Ocean Institute, to recommend avoiding this particular species when possible.

Biology

Icelandic scallops have separate sexes (gonochoristic) from birth, whereas most scallop species are hermaphrodites. Reproduction is by broadcast spawning, which is cued by rising ocean temperatures in June and July. After 6-10 weeks of floating as planktonic life, the larvae settle to hard sand and gravel surfaces. When settling they preferentially attach to dead hydroids, live hydroids, and algae using byssus threads.

Growth rate varies seasonally, by age, and across the species range, but the scallops generally reach maturity at 5 or 6 years old and can live in excess of 23 years.
Icelandic scallops are largely sedentary, often with large and dense coatings of epibionts, such as sponges and tube worms.

One thing that interests me right now about the Icelandic scallop, mainly because I'm spending my days doing a lot of GIS work now, is that the species is extremely temperature sensitive, with both high and low temperature limits. As the sea surface and bottom temperatures change, the stock densities and distribution of the scallop change as well. Similarly, it has known constraints in salinity, current flow velocities, depth and sediment types. This makes the Iceland scallop a good choice for a GIS-based habitat suitability modeling, using the range of potential climate change parameters to predict future range contractions or expansions and areas where stock recovery efforts or aquaculture are most likely to succeed over the long term.

Of course I also love scallops for their beautiful eyes, and yes... their taste!
I think this is one of my favorite recipes. I don't recall where it comes from originally or I'd credit it. Just make sure to use farmed or wild caught Bay scallops (Argopecten irradians) or Giant scallops (Placopecten magellanicus), not Icelandic scallops.

12 scallops
Sea Salt
2-3 tbsp olive oil (virgin)
4 tbsp chopped onion
1-2 tbsp chopped garlic (we go 3, we love garlic!)
1 dry bird pepper (or use dried thai pepper)
3 tbsp parsley
3 tbsp diced prosciutto
Saffron
Sherry
Fish Broth (splash)
12 clams

Sprinkle pinch of sea salt over scallops and let sit 5 minutes. In preheated pan on medium heat, add oil, onions, garlic and thai pepper. Cook until onions are wilted. Add scallops and pinch of saffron. Continue to cook on medium 3 more minutes. Add splash of fish broth, splash of sherry, clams and prosciutto. Cook additional 30 seconds to 1 minute. Serve with rustic bread.

References

Arsenault, D., Giasson, M., & Himmelman, J. (2000). Field examination of dispersion patterns of juvenile Iceland scallops (Chlamys islandica) in the northern Gulf of St Lawrence Journal of the Marine Biological Association of the UK, 80 (3), 501-508 DOI: 10.1017/S0025315400002198

GARCIA, E. (2006). The Fishery for Iceland Scallop (Chlamys islandica) in the Northeast Atlantic Advances in Marine Biology, 51, 1-55 DOI: 10.1016/S0065-2881(06)51001-6

Jonasson, J., Thorarinsdottir, G., Eiriksson, H., Solmundsson, J., & Marteinsdottir, G. (2006). Collapse of the fishery for Iceland scallop (Chlamys islandica) in Breidafjordur, West Iceland ICES Journal of Marine Science, 64 (2), 298-308 DOI: 10.1093/icesjms/fsl028

WROBLEWSKI, J., BELL, T., COPELAND, A., EDINGER, E., FENG, C., SAXBY, J., SCHNEIDER, D., & SIMMS, J. (2009). Toward a sustainable Iceland scallop fishery in Gilbert Bay, a marine protected area in the eastern Canada coastal zone Journal of Cleaner Production, 17 (3), 424-430 DOI: 10.1016/j.jclepro.2008.08.004

Pick a Card, Any Card

Another of the Ocean Challenge in the Classroom projects has been fully funded! So...
Pick a card any card, leave your pick in a comment or as a tweet to @eclecticechoes. The card with the most choices (or in a tie a random choice among the tied) will be featured here tomorrow.

Nautilus Night - Cephalopod of Diamonds

Ok. I said for each of the Ocean in the Classroom projects fully funded I would put up a post about one invert from the deck of cards I have been working on, along with a sneak peak at a card. So, since the Making Waves, Oceans and Landforms got fully funded, and in honor of Nautilus Night I bring you the Cephalopod of Diamonds - The Chambered Nautilus.

Classification for the Chambered Nautilus

Kingdom

Animalia

Phylum

Mollusca

Class

Cephalopoda

Order

Nautilida

Family

Nautilidae

Genus

Nautilus

Species

N. belauensis

Some interesting facts about the chambered nautilus (and other extant nautiloids):

The 6-7 (there is still debate on the status of one species) extant species of nautilus come from two genera, the 4-5 smooth nautilus'(genus Nautilus) and the 2 species of hairy nautilus (genus Allonautilus - literally "other nautilus").

They are the only remaining cephalopods that retain an external shell, which they use for defense and as a buoyancy control system. The shell, with buoyancy control, was a significant weapon evolutionarily, as it afforded the early cephalopods the protection of a thick shell yet the advanced buoyancy control unchained them from the sea floor as most of the periods marine arthropods were.

Modern nautilus are generally found on steep coral reef slopes at a depth of 200-400m during the day. They rise at night to feed near or at the surface, using the adjustable buoyancy of their gas filled shells to good effect during the vertical migration.

Unlike other cephalopods, the nautilus do not have a lensed eye. The nautilus eye is more like a pinhole camera, leading to the hypothesis that it uses olfaction to find it's prey (mostly shrimp and other crustaceans along with some small fish.)

Nautiloids also have upwards of 90 tentacles (compare with 8 arms of octopods and 8 arms an two tentacles of squid and cuttlefish.)

Last bit for this post is their lifespan and reproduction. Most cephalopods are short lived with overall lifespans of even the Giant Pacific Octopus being around 2-3 years. For most studied cephalopods natural death from old age occurs after mating, (and for females egg guarding), which is only done once (called semelparity). Nautilus can live in 15-20 years and mate year after year (iteroparity).

The nautilus are the ancient lineage of the cephalopods, descendants of and most like the orthocerids and other nautiloids that were a major predator of the seas in the Ordovician period. Modern nautiloids are the only cephalopods that retain their external shell and are often considered to be "living fossils" as they are very similar in appearance to the ammonites and nautiloids that emerged half a billion years ago in the Cambrian. However recent molecular studies are casting some doubt on the appropriateness of the "living fossil" moniker. Studies published in the past couple years have revealed that the 6-7 extant species of nautilus evolved much more recently, around 2 million years ago, in the seas around New Guinea. They then


Sinclair, B., Briskey, L., Aspden, W., & Pegg, G. (2006). Genetic diversity of isolated populations of Nautilus pompilius (Mollusca, Cephalopoda) in the Great Barrier Reef and Coral Sea Reviews in Fish Biology and Fisheries, 17 (2-3), 223-235 DOI: 10.1007/s11160-006-9030-x

Ocean in the Classroom Challenge

Today's a big outreach day!

First up, an outreach project I that has been part of my life for the past year is finally coming to be. This afternoon I will finally see the professionally printed version of my deck of cards that will be used to help teach molluscan diversity. They are still prototypes so I can't show them here just yet. Hopefully soon I can highlight a few of the cards along with some discussion about the animals on them and the process of making them. I am looking forward to hearing from the COSEE particpants at Avery Point who will be getting a sneak peak at them today through Saturday.

On a much larger scale Dr. M and Kevin have gathered together many of the top ocean bloggers to support some serious K-12 education outreach: Ocean in the Classroom Challenge. I just looked through the challenge and there are seven great projects in there, including several that are aquatic invertebrate centered. Personally I love the Invertebrates in my Tank, Waders and Coral Flip Book projects because they touch close to home, so to speak.

I would take the website hostage like the DSN boys are doing, but that won't work so well here where it has been so quiet lately. However, maybe the opposite will work, for each project that gets fully funded I'll put up a post on recent research about one of animals featured in the card decks.

Channeled Whelk with Egg Cases

Channeled Whelk with Egg Cases, originally uploaded by eclectic echoes.

Family friends bought us passes for Project Oceanology's Enviro Lab cruises at an auction this summer, and finally, as the summer draws to a close, we were able to take advantage of them. Project O is an outreach center that focuses on marine science and environmental awareness especially of the Long Island Sound ecosystem. Their Enviro Lab boats are equipped with a small sample trawl, water quality samplers and sediment samplers. I had been on the Enviro Lab boats with classes from the Marine Science undergraduate program at Avery Point (Project O is located on the Avery Point Campus).

For Johann and Tammy it was a new and exciting adventure. Johann's favorite part was examining the results of the benthic sample trawl. After seeing the Mystic Whaler (Which chanteyman extraordinaire Geoff Kaufman often sails aboard) he was inspired to sing a round of "Donkey Riding" as he reeled in the line from the trawl. The fun really started when he got to get really hands on with the samples helping quickly sort the haul and get all the animals into the large wet tanks. In the haul were a dozen Scup (Stenotomus chrysops), several Sea Robin (Prionotus carolinus), some Atlantic Moonfish juveniles (Selene setapinnis), what looked like a small striped bass (I didn't get to see it but that was the description), a feisty female little skate (Leucoraja erinacea) and a spotted hake (Urophycis regia).

While there was quite a number of vertebrates in the haul, there were far more inverts brought up. Among the inverts there were in excess of a hundred spider crabs (Libinia emarginata), two lobster (Homarus americanus,)(both female), two European Green Crabs (Carcinus maenas), one Jonah Crab (Cancer borealis), several broad-clawed hermit crabs (Pagurus pollicaris) and one male Horseshoe crab (Limulus polyphemus). Molluscs were well represented as well with many mud snails (Nassarius obsoletus) and slipper shells (Crepidula fornicata)as well as a half dozen loligo squid.

The real prize though was this female channeled whelk (Busycotypus canaliculatus formerly Busycon canaliculatus). Johann spotted her and pointed out the fact she was currently "laying" and egg case string. Soon after the animals were sorted into the tanks, the guide showed the whelk and explained the egg case string to the guests, then she carefully (more or less) dropped the whelk back into the sound.

The main reproductive time for the channeled whelks is the fall. Egg strings like the one this lady is laying will consist of 40-160 or more egg cases all joined by a tough leathery string. Each case may have as many as 100 eggs inside, though the average number of eggs per case is closer to 40. Not all the eggs in each case are fertilized though and the unfertilized eggs serve as food for the young whelks which emerge from the cases as miniature adults.

There is a small fishery for whelks here in the Long Island Sound, mostly sold in Italian markets as scungili. Unfortunately the most common bait used is chopped up horseshoe crab.

Life Photo Meme

A Cool New Backyard Visitor!

One of the joys about moving, and there are but few, is discovering the new critters inhabiting your property! My wife found this Spinybacked Orbweaver hard at work in our yard yesterday.

Zoanthid Histology

I uploaded some histology of a new zoanthid for collaborators in Japan to look at. Flickr is a great tool for sharing images and now I've found a work-related use for it! I don't have anything labeled but the descriptions for each image tell you what it is. The blue globby things are forams. Zoanthids are known to incorporate sand and sediment into their body wall to make them more rigid. As you can see from some of the cross sections, the mesenteries have very weak musclature. The staining protocol I used is called Masson's trichrome. Red stains for acidic tissues, like muscle fibers, while blue stains for basic tissues, such as connective tissue.

Hoverfly Closeup

Syrphid hoverfly on cornflower #4 by Lord V @Flickr

Wear your Invert

We made our annual pilgrimage to a shopping mall the other day to visit the Apple Store (Closed for renovations!) and the tea store. On our way out Tammy spied some cool earings hanging in a small shop. What caught her eye from outside the store was the blue heron Cloisonné earrings. Once inside though she fell for the Monarch Butterflies. Today when I got home she showed me the creators website bamboojewelry.com. Tammy was psyched that they had nudibranch pins and earrings!


Actually they have a nice collection of marine and terrestrial invertebrates.


A persfect gift for your invert lover (take that however you need to!) or for yourself. Of course if you insist on having relations with a porpoise, Bamboo has you covered there too. But seriously wouldn't you rather wear a nudi?

The Deepest Cuke

A WHOI summer student fellow, holding one of the deepest sea cucumbers ever found, recovered from the Mariana Trench. Stunning to think of this little echinoderm living 9,000-11,000m down with pressures of 16,000psi or more. Image copyright WHOI.

The deep exploration buzz online lately has justifiably been about the hopefully avoidable, premature retirement of the JSL manned subs – read up on the issue at Deep Sea News, then SIGN UP to try and save them – but there is another vehicle out there right now that deserves some praise: Nereus.

Out of Woods Hole, Nereus is an ROV designed from the ground up to go to the absolute depths of the oceans. On the 31st of May, it went all the way to the bottom of the Challenger Deep, the deepest spot in the oceans at 10,902m. Nereus is now the only currently operating vehicle to explore the Mariana Trench and only the third in history to have done so: the manned Trieste in 1960 and the ROV Kaiko in 1995-1998. Read more about the technological hurdles involved in designing and building Nereus, along with it's maiden voyage to the bottom of the seas. The very bottom.