Ocean Giants: Giant Clam

You don't have to look too deep in the ocean for exotic beauty because the vast coral reefs already offer some of the most spectacular underwater sights. Coral reefs, the marine counterpart of rainforests, serve as habitat to various species ranging from invertebrates such as mollusks to mammals such as sea turtles. And among the species of mollusks is the largest known bivalve, the giant clam Tridacna gigas. It is found in the Indo-West Pacific, from the intertidal zone to depths of 35 m (Bernard et al 1993) [1]. The largest known individual measured 137 cm in length and weighed 250 kg [2]. 

Giant clam on reef, photo from www.arkive.org

Giant clams are known for their unique ability to ‘self-feed’. How do they do it? During an early stage in their life cycle, they ingest dinoflagellate algae. The algae are not digested but rather propagate in the gut. Basically, the clam is dependent on this algae and filters sea water for it to grow at such length. Giant clam meat, i.e., from its adductor muscle, is in high demand. Unregulated harvesting of wild stocks posed and continues to threaten native populations throughout the Indo-Pacific. This led to attempts to develop harvestable cultured populations [3]. Because of this, information on the biology and ecology of giant clams were rendered available in the scientific literature. You may visit SeaLifeBase to view this information.

Giant clams in spawning tank in mariculture plant, photo from www.arkive.org

If you have other information on them, which you wish to include in our information system, please e-mail us at sealifebase@fin.ph or join us as a collaborator.

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[1] Bernard FR et al (1993) Catalogue of the Living Marine Bivalve Molluscs in China. Hong Kong University Press, 121 p.
[2] McClain, C.R., et al. 2015. Sizing ocean giants: patterns of intraspecific size variation in marine megafauna. PeerJ 2:e715. Accessed from https://peerj.com/articles/715/
[3] Munro JL (1993) Chapter 13: Giant clams. FFA Report 92/75.


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Collaborator of the Week: Dennis P. Gordon

Dr. Dennis P. Gordon is based at the National Institute of Water and Atmospheric Research (NIWA) at Wellington, New Zealand, where he is Principal Scientist and Manager of the Marine Biodiversity and Biosecurity Group. He is a distinguished global authority on the biology, paleobiology, systematics and evolution of phylum Bryozoa. Aside from collaborative environmental projects done for commercial clients, he is one of the leading biodiversity figures in New Zealand, specializing in marine biodiversity.

Within the span of his research career, he has primarily focused on the biology, paleobiology, systematics and phylogeny of Cretaceous to Recent Bryozoa. His work in these areas covered vast applications to biosecurity, biotechnology, conservation, fishing impacts and evolution, among others. Along with dedicated colleagues, he has described 687 new taxa, including 431 recent bryozoan species, 105 new fossil species and 144 higher taxa of Bryozoa. His key role as a biodiversity scientist led him to work on the total Phanerozoic biodiversity of New Zealand and global classification of life for biodiversity management. This milestone brought forth a 1758-page trilogy encompassing New Zealand’s entire living (> 56,200 species) and fossil (>14,000 species) biodiversity. Even with the bulk of his commitments, his passion for conservation extended his contributions to assessing marine adventive species, biosecurity risk and human impacts in the marine environment.

Having 45 years of research experience, he has written an astounding number of peer reviewed publications, forged ties with important local and international scientific and conservation institutions (serving on committees of the Ocean Biogeographic Information System, Catalogue of Life and World Register of Marine Species), and garnered numerous awards and recognition.

He has been a collaborator of the SeaLifeBase project since 2012 and made a noteworthy contribution for the Kermadec Island work at the same time. He provided us with references and validated bryozoan species for the Kermadec Island, which helped complete our coverage for this group of species.

We are indeed thankful and looking forward to more years of collaborating.

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Ocean Giants: Giant Isopod

The deep sea is full of wonders, and many creatures are waiting to be discovered. Technology makes it possible for scientists to go down the depths of our seas to study and identify these creatures. For example, the photo below was posted by a deep-sea technician in 2010 in the social site Reddit where he wrote, "I work for a Sub-sea Survey Company, recently this beast came up attached to one of our ROVs. It measures a wee bit over 2.5 feet head to tail, and we expect it latched onto the ROV at roughly 8,500 m depth. Unfortunately, the e-mail that these pictures were attached to came from a contractor, and the ship he was operating from is unknown, so I can't tell you what part of the earth this beast was living." Readers' responses ranged from curios to horrified [1]. 

Photo from NOAA/OER.

Later on, it was identified as Bathynomus giganteus, the giant isopod. Isopods are crustaceans (not bugs, even if they look like roaches). They dwell in the deep floors of the Atlantic and Pacific Oceans, and can grow up to 50 cm in length. They often figure as bycatch in trawl fisheries [2]. Not only are they the largest isopod, they also have the largest egg (~10 mm) among pericaridans. Egg brooding is trait of the giant isopod, which may take several months, and at which time, females stop to feed. Instead, they burrow in the sediments and remain quiescent throughout the brooding period [3].

To know more about the giant isopod, visit SeaLifeBase.

If you have other information on them, which you wish to include in our information system, please e-mail us at sealifebase@fin.ph or join us as a collaborator.

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[1] Braun, D. 2010. Bathynomus giganteus: terrifying sea beast hauled up. Accessed on 13/02/2015 from http://voices.nationalgeographic.com/2010/03/31/bathynomus_giganteus_terrifying_sea_beast/
[2] McClain, C.R., et al. 2015. Sizing ocean giants: patterns of intraspecific size variation in marine megafauna. PeerJ 2:e715. Accessed from https://peerj.com/articles/715/
[3] Barradas-Ortiz, C., et al. 2003. Seasonal reproduction and feeding ecology of giant isopods Bathynomus giganteus from the continental slope of the Yucatán Peninsula. Deep-Sea Research I 50(4):495-513. Accessed from http://www.sciencedirect.com/science/article/pii/S0967063703000360


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Collaborator of the Week: Roberto Pillon

Roberto Pillon is an Italian underwater photographer and naturalist whose photos are published in several books. He has a degree in Economics and though he is not a marine biologist, he is considered a great connoisseur of marine species identification from photographs. He is very passionate of the techniques in proper identification of marine organisms and has studied major publications as well as analyzed a large amount of photos to acquire the knowledge and skills needed in this field. In his most comprehensive study entitled "Astropecten of the Mediterranean Sea", he was able to distinguish six species of sea stars including Astropecten aranciacus, A. jonstoni, A. irregularis, A. spinulosus, A. bispinosus, and A. platyacanthus using methods of photo-identification. In this unique manner of classification, he basically observed distinct features in comparison to the descriptions described by the species authors. Other than sea stars, he also applied this technique to identify fishes and other echinoderms of Mediterranean Sea.

Since 2008, he has been a collaborator of SeaLifeBase and has contributed over 400 photos of different marine organisms taken mostly from Croatia, Greece, Italy and France. He also perpetually and promptly reports errors in photo identification. Likewise, he collaborates with many admired experts and other sites like Fishbase, WoRMS, DORIS, Naturamediterraneo, Hippo-ATLAS, etc.

Ocean Giants: Nomura's jellyfish

If the longest medusozoid is the lion's mane jellyfish, the heaviest would be Nomura's jellyfish. Scientifically known as Nemopilema nomurai, it is found endemic to the East Asian Marginal Seas - Bohai Sea, Yellow Sea and East China Sea [1]. The largest recorded species measured 2 m in bell diameter and weighed 200 kg [2].

Photo by Choi, Jong-Kwan taken in Korea.

Majestic as this species can be, fishers have found them troublesome. Since the early 2000s, jellyfish bloom has threatened the fisheries of Japan; instead of fishes, nets were full of this jellyfish. Studies conducted to determine the cause of the increasing frequency of jellyfish blooms in Japan revealed global warming and overfishing as the main factors [1, 3]. 

1. Global warming: It appears that podocysts are carried out by the Tsushima Current from the Yellow Sea to the Sea of Japan. Exposure to higher temperatures triggers their development into medusa form. This explains why the bloom occurs only in Japan, not in China nor in Korea. 
2. Overfishing: Note that both fish and jellyfish prey on zooplankton. Thus, excess fishing is advantageous to jellyfish because of decreased competition. Since there are fewer fishes, they can easily dominate the area where food is readily available.

Photo by Shin-ichi Uye, Hiroshima University, posted on BBC.

To know more about the biology of Nomura's jellyfish, visit SeaLifeBase.

If you have other information on them, which you wish to include in our information system, please e-mail us at sealifebase@fin.ph or join us as a collaborator.

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[1] Uye, S (2008) Blooms of the giant jellyfish Nemopilema nomurai: a threat to the fisheries sustainability of the East Asian Marginal Seas. Plankton Benthos Res 3 (Suppl.):125-131.
[2] McClain, CR, et al (2015) Sizing ocean giants: patterns of intraspecific size variation in marine megafauna. PeerJ 2:e715. Accessed from https://peerj.com/articles/715/
[3] Kawahara, M, Ohtsu, K, Uye, S (2013) Bloom or non-bloom in the giant jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae): roles of dormant podocysts. J. Plankton Res. 35(1):213-217.

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Collaborator of the Week: Guido T. Poppe

Photo from wikipedia.org

Guido T. Poppe is known for his contribution in conchology research and an author of more than 20 books and publications that mainly focus on families Volutidae and Trochidae. At a young age, he has had a great interest in the oceans and the different forms of life living in it.  His fascination led him to develop a career as a malacologist. While in this field, and in numerous years of diving in European waters and tropical seas, he was able to compile an extensive collection of photographs of seashells and other marine organisms [1, 2].

In 2003, Guido Poppe decided to move from Belgium to the Philippines and continued his profession as a conchologist. He described over 130 of new molluscs species [2] and mostly on the Philippine malacofauna [1]. In fact, there are more than 30 species that have been named after him having the epithets poppei, “guidopoppei” or guidoi [2].

In 2010, he together with his son Philippe Poppe, became collaborators of SeaLifeBase and have contributed over 2,000 photos as well as 2 volumes of their book “Philippines Marine Mollusks”. They also have an online database of digital pictures, the POPPE-IMAGES, aiming to document the marine life in the Philippines [3]. This information system provides over 70, 000 online images [3]. Also, they created the journal, Visaya, a rapidly growing periodical specialized in the taxonomy of mollusca. [2].

TRIVIA: Guido Poppe named among the over 300 shells he already described, the topsnail Calliostoma mariae after his mother Maria Peyskens, and three other sea snails species Calliostoma philippei (Poppe, 2004), Calliotropis philippei (Poppe, Tagaro & Dekker, 2006) and Bayerotrochus philpoppei (Anseeuw, Poppe & Goto, 2006) after his son [1].

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[1] Guido Poppe. http://en.wikipedia.org/wiki/Guido_Poppe [Accessed 03/05/2015].

[2] Guido T. Poppe. http://www.poppe-images.com/?t=5 [Accessed 03/05/2015].

[3] Poppe Images About Us. http://www.poppe-images.com/?t=2 [Accessed 03/05/2015].

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Ocean Giants: Japanese Spider Crab

What crawls, has 8 legs and can be scary and creepy?

Yes, that's correct. 

A spider. 

But did you know that there are spiders at the bottom of the sea? They look like spiders but they're actually crabs.

The largest of these is the Japanese spider crab, Macrocheira kaempferi. It is endemic to southern Japan, found at depths between 50 to 400 m [1], hence the name; although its distribution has extended to eastern Taiwan [2]. The largest known specimen on display at the Scheveningen Sea Life Center in the Netherlands has a legspan of 3.7 m and weighs 13.6 kg [3].

Little is known on the biology of this species. Thus, if you have other information on them, you can e-mail us at sealifebase@fin.ph or come be a collaborator.

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[1] Okamoto K (1993) Influence of temperature on survival and growth of larvae of the giant spider crab Macrocheira kaempferi (Crustacea, Decapoda, Majidae). Nippon Suisan Gakkaishi 59(3):419-424.
[2] Huang JH, Yu H, Takeda M (1990) Occurrence of the giant spider crab, Macrocheira kaempferi (Temmink, 1836) (Crustacea, Decapoda, Majidae) in Taiwan. Bulletin of the Institute of Zoology, Academia Sinica 29(3):207-212.
[3] McClain CR, Balk MA, Benfield MC, Branch TA, Chen C, Cosgrove J, Dove ADM, Gaskins LC, Helm RR, Hochberg FG, Lee FB, Marshall A, McMurray SE, Schanche C, Stone SN, Thaler AD (2015) Sizing ocean giants: patterns of intraspecific size variation in marine megafauna. PeerJ 3:e715.


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SeaLifeBase welcomes its new members!

SeaLifeBase wholeheartedly welcomes its two (2) new members: Rachell Gallano and Rubyann Polido. Both started last November 2014. Three months have passed and we wanted to know how are they feeling so we asked them to share their experiences and expectations since they joined the team. Here's what they have to say.

Rachell Gallano

Academic Profile

I earned my Bachelor's degree in Biology from Southern Luzon State University (SLSU) in Lucban, Quezon back in 2008. In the same year, I became a College Instructor of the Natural and Biological Sciences Department in SLSU. After two years, I pursued my Masters degree in Zoology at the University of the Philippines Los Baños (UPLB). At that time, I was a full-time student and a recipient of the Department of Science and Technology-Accelerated Science and Technology Human Resource Development Program (DOST-ASTHRDP) scholarship. My research on the “Prevalence and intermediate hosts of acanthocephalan parasites in cultured Nile tilapia” during my masters received the Best Paper award during the 6^th CAS-UPLB Student and Faculty Research Conference in December 2013. My research interests have been parasitology and ecology of aquatic ecosystems. I also plan to pursue a Doctoral degree in the future. 

Venturing into marine research

From academe, I engaged myself into marine research. I entered this kind of career to develop my scientific writing and communication skills.

Experience and Expectations

I was tasked to handle the SeaLifeBase facebook and blogspot pages wherein I feature and share information and latest news about various non-fish marine organisms on a daily basis. For the past three months since day one, I have also developed my written communication skills with my continuous effort to contact SeaLifeBase collaborators from different parts of the world. I also learned to multi-task by managing my time doing both administrative-related work and searching for vernacular names of different marine species. This kind of career is not just a challenge but also a rewarding task especially when you have accomplished it well.

As of now, I am still undecided about future plans pertaining to my career but one thing is certain, I love and enjoy my job and colleagues here in SeaLifeBase. 

Rubyann Polido 

Academic Profile

I hold a Bachelor's degree in Biology major in Ecology from the University of the Philippines Los Baños (UPLB). I did a special problem on the phenotypic plasticity of an ornamental plant, Hoya albida, under the supervision of Prof. Faith S. Maranan. I presented my study last May 2014 in the Philippine Society for the Study of Nature. While still figuring out my niche in marine research, I presently have this growing interest in mangroves and sea turtles.

Venturing into marine research

While checking online courses in edX, I stumbled upon a course offered by the University of Queensland entitled Tropical Coastal Ecosystems. Fundamentals of marine biology were discussed there and I found it really interesting to the point that I dedicated months to complete the course - jotting down notes, taking short quizzes and watching videos. Taking the course was free so I maximized that opportunity.  Few months later, I found a post on a social media regarding a vacancy in SeaLifeBase. How timely! Curiosity took me away so then and there I applied. More importantly, I felt the urge that I had to be assertive of what I really want; to be a marine biologist, I hope, can be that fulfilment.

Experience and Expectations

It was said in the post that the job entails encoding of non-fish marine species, so I already expected a bonding with the computer. It was a good fit because what I needed was an introduction to marine species before I can specialize on a specific field of study. The environment? I already felt like I have a set of good friends. It was comforting to have met dedicated colleagues who have their own field of interest. That makes you want to develop your own.

First day jitters turned to weeks. Research is tough. But good things come out of patience and great training. Learning how to zero in on a specific information and encoding it is definitely a discipline. And it is really satisfying when you finally come across that information you have been looking for so long. Among others, exhausting available data online, scrutinizing details, entering a bibliography, citing a reference properly are things that I will be grateful for learning. It is also a plus to be in an environment where I can forge my path towards the field I want to specialize on in the future. 

We are grateful to the both of you because we are able to positively contribute to your growth as marine researchers. We hope that you will enjoy not only the company of its team members but also the project as it is. Remember that we are one in conservation!

Ocean Giants: Giant Tube Worm

When you think of worms (not the nasty things you normally associated with stomachs), what first comes to mind are long and slimy creatures burrowing themselves in the ground. Not all worms are like that, though. Take for example the Christmas tree worms we featured back in 2012 (see article here). At first glance,  without a background check on the species, surely you won't think that it's a worm. 

Here we feature a "not so ordinary" worm, that is, the giant tube worm, Riftia pachyptila. It is the world’s largest deep sea annelid worm (Family Siboglinidae, Order Sabellida, Class Polychaeta) found in hydrothermal vents in the East Pacific, measuring up to 2 m in length. This is a sessile worm, contrary to the picture of worms moving about. Although it lacks a digestive system, its nutrition is dependent on vent plumes through an endosymbiotic relationship with a chemoautotrophic bacteria stored in a specialized organ called trophosome [1]. The plume is a gill-like organ, made up of a complex network of blood vessels thus the red coloration (see image below) [2].

Giant tube worm plume (photo by Peter Batson, posted in www.arkive.org).

Little is known on the biology of this species (see what SeaLifeBase has on it here). Thus, if you have other information on them, you can e-mail us at sealifebase@fin.ph or come be a collaborator.

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[1] McClain CR, Balk MA, Benfield MC, Branch TA, Chen C, Cosgrove J, Dove ADM, Gaskins LC, Helm RR, Hochberg FG, Lee FB, Marshall A, McMurray SE, Schanche C, Stone SN, Thaler AD. 2015. Sizing ocean giants: patterns of intraspecific size variation in marine megafauna. PeerJ 3:e715.
[2] Van Dover, CL. 2000. The ecology of deep sea hydrothermal vents. Princeton University Press, New Jersey, 424 p.


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