26 June 2013

Surveying robots and endangered marine life

Natural history surveying has evolved over time, from from boat-, land-based, and plane/helicopter surveys to current high technology robotics [1]. 

Underwater robots called gliders performing digital acoustic monitoring (DMON) deployed in late 2012 by a team of researchers from Woods Hole Oceanographic Institution (WHOI) in the central Gulf of Maine captured baleen whale calls that were identified as those from North Atlantic right whales, an endangered species [2]. This tool overtakes the opportunistic sightings of old techniques, as it records unique whale calls and confirms their location through reconnaissance data with real-time updates.

These robots increased our capacity to discover more about the life history of difficult to observe animals to more than ten-fold and may help extend our knowledge of threatened large pelagic species like whales, dolphins, swordfishes and whalesharks.

To know more about marine endangered species visit SeaLifeBase.
[1]  Eberhardt, L.L.; Chapman, D.G.; Gilbert, J.R. (1979) A review of marine mammal census methods. Wildlife Monographs 63:3-46.

[2] Macroevolution.net (2013) Detecting endangered whales. http://www.macroevolution.net/marine-robots.html#.UagR55yP_YN [Accessed 31/05/2013].

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24 June 2013

Wind sailors of the sea

Have you ever walked along the beach and encountered a fleet of bluish mussels on the shore? They are in fact not mussels but hydrozoans, famously known as by-the-wind sailors.  

Although physically similar with the Portuguese man o' war, this is not a jellyfish. Scientifically called Velella velellait is the only known species under the genus of free-floating hydrozoans. It is found worldwide in both tropical and temperate waters. With a deep-blue rectangular float and an upright triangular sail, it looks like a miniature sailboat, on which its name was coined. 

This colonial species is made up of clustered polyps/zooids categorized into two types: gastrozooids and gonozooids. Gastrozooids function for plankton feeding using its tentacles (see photo above), while gonozooids have a reproductive function, that is, to constantly release medusa to the open waters. Having no means of locomotion, they are at the mercy of the wind to move around the seas and are thus, prone to mass-strandings on coastal beaches.

To know more about the by-the-wind sailors, visit SeaLifeBase.

If you have other information on them, you can e-mail us at sealifebase@fin.ph or come be a collaborator.

Source: Monterey Bay Aquarium (MBARI). See page link here.Photos by Christian Coudre.
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19 June 2013

The red rainbow of the deep sea

The most amazing sea creatures can be found in the deep sea. One such species whose name can be a tongue twister is the bloodybelly comb jelly, Lampocteis cruentiventer

Photo by Kevin Raskoff/MBARI (c) 1999.

It is the only known species under the genus Lampocteis, first described and identified in 2001 by Harbison, Matusmoto and Robison. It was named as such because of its blood-red stomach. Light is diffracted from its ciliated comb rows that beat continuously to propel it through the water column. This contributes to the sparkling display of colors along its comb rows.


In the deep sea, shiny objects can be perceived as prey. However, despite its radiant color, this species is invisible to its predators. And, it also masks the bioluminescent prey it swallows from other potential predators. Taking advantage of the conditions of its environment, it has developed stealth to shield itself from prying predators. Not bad, aye?

If you want to share what you know about this species (e.g. morphology, distribution, life history, etc.) you can help us by becoming a collaborator, just e-mail us at sealifebase@fin.ph.

Visit SeaLifeBase to know more about comb jellies.

Source: Monterey Bay Aquarium (MBARI). See page link here.

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18 June 2013

Examination of a rare whale species

Photo: New Zealand Government

The spade-toothed beaked whale (Mesoplodon traversii) is one of the world's rarest whale species. The only known specimen is from an incomplete skull [2]. However, recent reports indicate that it is present in New Zealand [1] and in Robinson Crusoe Island, Juan Fernandez Archipelago, Chile [2]. Even more recently, two individuals, a mother and calf, were found live-stranded on Opape Beach, New Zealand in 31 December 2010, though these eventually died. DNA analysis on the remains confirmed that these individuals were of the spade-toothed beaked whale. This is the first time that a complete morphological account of this animal was done. Thus, stressing the importance of reference collections and genetic data in species cataloguing, especially in the case of rare species such as this whale [3].

To know more about beaked whales, visit SeaLifeBase.
[1] Wilson, D.E.; Reeder, D.M. (eds.) (2005) Mammal Species of the World. A Taxonomic and Geographic Reference (3rd ed). Johns Hopkins University Press, 2, 142 pp.
[2] Rice, D.W. (1998) Marine Mammals of the World Systematics and Distribution. Special Publication number 4: The Society for Marine Mammalogy. 231p.
[3] Thompson,K.; Baker, C.S.; van Helden, A.; Patel, S.; Millar, C.; Constantine, R. (2012) The world's rarest whale. Current Biology 22(Issue21):R905-R906.

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15 June 2013

A squid's human-like pregnancy

Gonatus onyx, commonly known as the black-eyed or clawed armhook squid, is abundantly found in the Atlantic and Pacific oceans. Little has been known about its life history because they spawn at great depths, making it difficult for researchers to study them. But with the recent developments in technology and fishery, Seibel and his colleagues (2005) were able to observe its brooding behavior - a very important insight on the reproduction of this species.

Squids are believed to be non-guarders, that is, they deposit their eggs on the sea floor and let them develop on their own. This species, though, begs to differ. It uses its hooks to hold the egg mass (2,000-3,000 eggs), extending from the mouth to well beyond its arms. Because of low temperatures (this happens at X,XXX m depths) and the relatively large size of their eggs, egg development is prolonged. The female squid can, therefore, carry this egg mass for a maximum of 9 months, much like women of our species. And despite of muscle degeneration at sexual maturation, female squids are able to protect their eggs from the inevitable threat imposed by the deep sea. All mothers have this intuition, regardless of what species they are. As Barbara Kingsolver once said, "Sometimes the strength of motherhood is greater than natural laws."

To know more about the black-eyed squid, visit SeaLifeBase.

If you have other information on them, you can e-mail us at sealifebase@fin.ph or come be a collaborator.

Seibel, B.A., B.H. Robison, and S.H.D. Haddock. 2005. Post-spawning egg care by a squid. Nature (Brief Communications) vol. 438, 15 December 2005 issue, p.929. See article here.

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