The tiny whale shark caught off the Philippine coast near San Antonio on March 6 has been confirmed by WWF to be the smallest live whale shark on record ever to be captured and released in the Philippines and arguably also the smallest living whale shark ever to be scientifically recorded.

Picture by WWF PF. Support WWF

The impressive Whale shark, Rhincodon typus, is the largest fish on the planet. The biggest specimen regarded as accurately recorded was caught in Pakistani waters in 1947 and measured 12.65 metres (41.50 ft) in length, with a girth of 7 metres (23.0 ft) and a weight exceeding 21.5 tonnes (47,300 lb).

The small specimen caught near San Antonio was on the other hand no longer than 15 in (38 cm) and may be what biologists call a neonate, i.e. a newborn. This is very interesting, since we still do not know to which part or parts of the world Whale shark females migrate to give birth to their pups. The finding of this tiny pup has caused scientists to speculate that the Philippine waters might be one of the places on the planet where the biggest fish in the world is born.

So, how did this petite Whale shark end up in human hands? On the morning of March 7, word reached Tourism Officer Pedragosa that a whale shark had been caught near San Antonio the day before. Pedragosa immediately sent Butanding Interaction Officer Guadamor to inform the town’s Municipal Agricultural officer Rabulan, and at this point, Aca, WWF’s Project Leader in Donsol, the municipality in which San Antonio is located, also became involved. When a shark is caught, time is of course crucial – examining the animal is important from a scientific point of view, but you don’t want to subject the shark to more stress than necessary. Aca therefore joined the officers of tourism, agriculture, and interaction at the tourism office right away and together they hastily drew up an operational plan and headed for San Antonio. At this stage, Berango, Chief of Police of Pilar, had also been alerted and Ravanilla, Regional Director of Tourism, had informed the resorts closest to the site.

The Chief of Police met up with Aca and the ministers at the seashore, where they found not a gigantic whale but a small stick jammed into the sand with a rope leading away from it into the ocean. As they followed the rope, they saw that it was tied around the tail of the smallest whale shark they had ever encountered before.

Whale Shark – Picture GNU Licensed

The team examined the shark to make sure that it had not been hurt, gave it food, measured it and documented the unique find. Less then three hours after the report first reached the tourism officer, the shark had been safely transferred to a big, water-filled plastic bag and the team was now heading towards deeper water where the shark could be released. Releasing it close to shore was not considered safe enough since the shallows in this area contains a lot of nets.

All this action took place in Sorsogon, a Philippine province famous for hosting the largest known annual congregation of whale sharks in the world. The province has become a popular destination for vacationers interested in snorkelling with sharks and going on shark safaris, and WWF is therefore working with local residents to develop and improve sustainable eco tourism practices along the coast.

Chinese ichthyologists Yang, Chen and Yang have described three new species of snow trout in a paper[1] published in the journal Zootaxa[2]. All three species have been described from material previously identified as one single species, Schizothorax griseus. True trouts belong to the Salmoninae subfamily in the Salmonidae family, but snow trouts are members of the family Cyprinidae.

Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cypriniformes
Family: Cyprinidae
Genus: Schizothorax

New species: Schizothorax beipanensis

Schizothorax heterophysallidos

Schizothorax nudiventris

Schizothorax beipanensis

Schizothorax beipanensis is found in southern China where it inhabits the Beipan River drainage, a part of the Pearl River drainage. It has been encountered in both slow-flowing deep pools and fast-flowing rivers with clear water and over a wide range of different bottom substrate, from mud and sand to rocks, boulders and pebbles.

Schizothorax beipanensis differs from its close relatives by having well-developed upper and lower lips (the lower lip is actually tri-lobed), no horny sheath on the lower jaw, and a continuous postlabial groove with a minute median lobe.

Schizothorax heterophysallidos

Just like Schizothorax beipanensis, the snow trout Schizothorax heterophysallidos is found in the Pearl River drainage in southern China, but it lives in the river drainage of Nanpan, not Beipan. Schizothorax heterophysallidos lives in small streams where the bottom consists of sand and pebbles.

The name heterophysallidos is derived from the unusual swim bladder of this fish; physallis is the Greek word for bladder and heteros means different. In addition to the swim bladder (the posterior chamber of the air bladder is three to six times longer than the anterior chamber), Schizothorax heterophysallidos can be recognized on its well-developed and trilobed lower lip, thin upper lip, and blunt snout. It has a continuous postlabial groove with a minute median lobe and the last unbranched dorsal-fin ray has a strong lower part. In mature specimens, the abdomen lacks scales.

Schizothorax nudiventris

Schizothorax nudiventris also lives in southern China, but in the upper parts of the Mekong River drainage. The Mekong basin is one of the richest areas of biodiversity in the world. More than 1200 species of fish have been identified here and the number is believed to increase as the area becomes more thoroughly explored by science.

Schizothorax nudiventris has a well-developed and trilobed lower lip, thin upper lip, blunt snout, and continuous postlabial groove. The body is decorated with irregular black spots on the sides, and the last one-quarter of the last unbranched dorsal-fin ray is soft. In mature specimens, the abdomen has no scales, and it is this feature that has given the fish its name nudiventris. Nudus is the Latin word for naked, while venter means abdomen.

No, this fish is not animated by Pixar – it is a very real fish created by Mother Nature deep down in the ocean. Its name is Macropinna microstoma and it has puzzled ichthyologists since it was first described by Chapman in 1939.

Macropinna microstoma, also known as the Barreleye fish, has a fluid-filled dome on its head through which the lenses of its barrel shaped eyes can be clearly seen. The fish lives at a dept of 600-800 metres where it spends most of its time hanging almost completely still in the water.

Even though the Barreleye was described by science in the late 1930s, the transparent dome is a fairly new discovered since it is normally destroyed when the fish is brought up from the deep. Old drawings of the fish do not show the see-through part of the head and the species was not photographed alive until 2004.

Thanks to new technology, it is now possible for researchers to explore the deep sea much more efficiently than ever before and we are therefore learning more and more about the weird and wonderful creatures that inhabit these baffling parts of the planet. It has long been known that the tubular eyes of the Barreleye are good at collecting light; an adaptation to a life deep down in the ocean where light is scarce. The eyes were however presumed to be fixed and the fish was therefore believed to have a very narrow upwards-facing tunnel-vision. Researchers Bruce Robinson and Kim Reisenbichler from the Monterey Bay Aquarium Research Institute (MBARI) has now changed this notion completely by providing evidence suggesting that this fish can rotate its eyes within the transparent dome in order to see both upwards and straight forward. Robinson and Reisenbichler observed that when suitable prey, e.g. a jellyfish, is spotted, the fish will rotate its eyes to face forward as it turns its body from a horizontal to a vertical position to feed.

Robinson and Reisenbichler were able to get close to five living Barreleyes using Remotely Operated Vehicles (ROVs) at a depth of 600-800 meters off the coast of Central California. In addition to observing and filming the fish in its native habitat, the researchers also captured two specimens and placed them in an aquarium for a few hours in order to study them more closely.

Live specimens of Macropinna microstoma turned out to have beautifully coloured green eyes; probably in order to filter out sunlight from the surface of the ocean since this would make it easier for the fish to spot bioluminescent jellyfish. Robinson also suggests that Macropinna microstoma might be using its supreme eye sight to steal food from siphonophores[1].

If you want to know more about the intriguing Barreleye fish, check out the paper BH Robison and KR Reisenbichler (2008) – Macropinna microstoma and the paradox of its tubular eyes. Copeia[2]. 2008, No. 4, December 18, 2008.

War on clams has been declared at Lake Tahoe, a large freshwater lake in the Sierra Nevada Mountains of the United States. Scuba divers have been enrolled in a 400,000 USD project aiming to completely rid the lake of all Asian clams. The anti-clam endeavour is scheduled to begin in mid-March and is a combined effort by the governments of Nevada and California.

The Asian clam (Corbicula fluminea) is native to Asia and parts of Africa where it inhabits streams, canals and lakes. In this part of the world it is a natural part of the ecosystems and is even known as the prosperity clam or good luck clam. The Asian clam was introduced to North America in the 1920s by Asian immigrants for whom it was an appreciated source of food. It would however take until 2001 before the first specimens were encountered in Lake Tahoe. Since the first finding, the clam has been collected from numerous locations Tahoe’s southeast shore and authorities now fear that it will pave the way for even more dangerous invasive species such as the Ukrainian Quagga mussel (Dreissena rostriformis bugensis) and the Russian Zebra mussel (Dreissena polymorpha).

”We’re concerned they could create a positive settlement situation for the quagga mussels,” says Steve Chilton, aquatic invasive species coordinator for the U.S. Fish and Wildlife Service. ”We’re basically looking at all avenues through which the quagga mussel could get into the lake and eliminate that risk factor as much as possible.”

Steps so far have primarily focused on mandatory boat inspections to ensure no mussels are attached to them when they launch into the lake, but scuba divers participating in the new anti-clam project will actually be removing Asian clams from Lake Tahoe’s southeast shore. Starting in mid-March, divers will place plastic sheets, so called bottom barriers, over selected clam beds in order to deprive the clams of oxygen and nutrients. Divers will also carry out ”diver-assisted suction”, e.g. manually vacuum clams off the bottom of Tahoe.

”This needs to be done. We have to get our hands around the Asian clam problem,” Tahoe Regional Planning Agency spokesman Dennis Oliver told the Reno Gazette-Journal. ”We need to find out what works and what works best. Once we know that, we can develop a program.”

Invasive mussel species are known to form huge populations in environments where they lack natural predators and can for instance clog water intakes, attach themselves to boats and docks, and litter sandy beaches.

North America is not the only continent with an Asian mussel problem; Corbicula fluminea has begun to spread throughout Europe as well. It was found in the Rhine as early in the 1980s and then gradually found its way into the Danube through the Rhine-Maine-Danube Canal. In 1998 the first specimens were found in the Elbe and the species is now also present in the rivers of Portugal.

A new species of catfish belonging to the genus Lithogenes has been described by ichthyologists Scott Schaefer and Francisco Provenzano in a recent issue of the journal American Museum Novitates[1].

The new fish has been given the name Lithogenes wahari, after Ruá-Wahari, the Piaroapeople’s God of Creation[2]. The species is known from the Cuao River, a part of the Orinoco River drainage, where it inhabits clear and swift forest streams with exposed bedrock substratum. It was actually collected over 20 years ago by anthropologist Stanford Zent, but it would take until 2001 before the fish was found again by Scott Schaefer and Francisco Provenzano.

Lithogenes wahari is the third scientifically described member of the small genus Lithogenes and can be distinguished from its two close relatives by the absence of odontodes on the proximal portion of the ventral surface of the first pelvic-fin ray, the lack of accessory premaxillary teeth, the extensive ridges present on the thickened skin of the pelvic pad, and the intense pigment band that runs along the base of the anal fin. There is also a diffuse spot located midlength on the anal fin rays.

Interestingly enough, the new information on this Lithogenes member has led ichthyologists to suggest that the common ancestor of the Loricariidae and Astroblepidae was a fish capable of climbing rocks by grasping them with its mouth and pelvic fins.

Picture here

The hydrothermal vents that line the mid-ocean ridges are a major source of iron for the creatures living in the sea. Humans are not the only ones who suffer when iron becomes scarce; creatures such as phytoplankton are known to grow listless in waters low in iron, even if they are drifting around in an environment rich in many other types of nutrients.

Earlier, scientists assumed that the iron exuded from hydrothermal vents immediately formed mineralized particles as soon as it came in contact with the salty water – a form of iron that is hard to utilize for living creatures.

New research has however unveiled that some of the iron spewed out from these vents actually remain in a form that is easy to absorb for oceanic beings. According to researcher Brandy Toner, a surprising interaction between iron and carbon in hydrothermal vents serves to stop the corrosion.

“Iron doesn’t behave as we had expected in hydrothermal plumes. Part of the iron from the hydrothermal fluid sticks to particulate organic matter and seems to be protected from oxidation processes,” Toner explains.

The research was carried out on hydrothermal vent particles collected by the team from the Tica vent in the Eastern Pacific Rise. With the help of the Advanced Light Source synchrotron at the Lawrence Berkeley National Laboratory, Toner was able to analyze the particles using focused X-ray beams.

Iron is a key player in this newly discovered process in the ocean, but the exact mechanisms remains unknown.

“So the question becomes, what are those organic compounds? Are they organic compounds like in oils and tars or is it actually the stuff of life?”, says Chris German, co-author of the paper. “Brandy’s work doesn’t mean that these [carbon-iron] complexes are definitely alive. But, this is a possible smoking gun. This paper opens up a whole new line of research and asks a new set of questions that people didn’t know they should be worrying about until now. A bit of work on a tiny nanometer scale can force you to ask questions of global significance.

Perhaps hydrothermal venting, a process traditionally believed to be a completely inorganic process, actually is a part of the organic carbon cycle on our planet.

The paper “Preservation of iron (II) by carbon-rich matrices in a hydrothermal plume” by Brandy Toner and her colleagues[1] has been published in Nature Geoscience[2].

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Aquarium Toplist function added

Zoology Prof. Yossi Loya at the Tel Aviv University in Israel has discovered that corals changes sex to survive periods of stress, such as high water temperatures. By observing the behaviour of Japanese sea corals he discovered that stressed female mushroom coral (fungiid coral) change gender to become males, and that male corals are much better at handling stress and fare better at surviving on limited resources. Not all females go through his change but many do and most of the population is therefore male during periods of intense stress.

Yossi Loya says: “We believe, as with orchids and some trees, sex change in corals increases their overall fitness, reinforcing the important role of reproductive plasticity in determining their evolutionary success. One of the evolutionary strategies that some corals use to survive seems to be their ability to change from female to male, As males, they can pass through the bad years, then, when circumstances become more favourable, change back to overt females. Being a female takes more energy, males are less expensive to maintain. They are cheaper in terms of their gonads and the energy needed to maintain their bodies. Having the ability to change gender periodically enables a species to maximize its reproductive effort.”

Loya’s discoveries have been published in the Proceedings of the Royal Society B. The professor hopes that this new knowledge will help coral farmers by allowing them to reproduce the hardy Fungiid corals more effectively.

Loya has been studying coral reefs for more than 35 years and won the prestigious Darwin Medal for a lifetime contribution to the study of coral reefs. He is also involved in coral rehabilitation projects in the Red Sea and is a professor at the Tel Aviv University in Israel.

The oceans of the world absorb a large part of the carbon dioxide released into the atmosphere by us burning fossil fuels, burning forests to make room for fields, etc. This have helped slow down global warming, but new studies shows that it might have a devastating effects on certain fish species such as clown fish. Tests performed on clown fish larvae have shown that increased levels of carbon dioxide can make them disoriented an unable to find a suitable home and avoid predators. The pH level in the ocean has dropped 0.1 since pre-industrial times due to the absorption of carbon dioxide and researchers believe that it will fall another 0.3-0.4 before the end of this century.

This increased acidicy of the water can cause serious problems for clown fish larvae, since clownfish larvae lose the ability to sense vital odours in more acidic waters – probably owing to the damage caused to their olfactory systems. Kjell Døving (Oslo University), co-author of the rapport that was published in US journal Proceedings of the National Academy of Sciences, says “They can’t distinguish between their own parents and other fish, and they become attracted to substances they previously avoided. It means the larvae will have less opportunity to find the right habitat, which could be devastating for their populations.“

The research indicates that other species might be affected in a similar way and might have a hard time finding their way to suitable habitats if carbon dioxide levels raises in the oceans.

About the study

The study was executed in such a way that the researchers checked how well clownfish larvae could detect smells in normal sea water (pH 8.15) and how well they could detect odours in more acidic water (at levels predicted to be a reality around the year 2100 and later). The test showed that at pH 7.8 the larvae stopped following scent trails released by reefs and anemones and started following sent trails they would normally avoid; scents that are associated with environments not suitable for clown fish. The larvae also lost the ability to use smell to distinguish between their parents and other fish. At pH 7.6 the larvae were unable to follow any kind of odour in the water, and instead swam in random directions.

The yearly manatee count revealed a record number of manatees this year. The survey counted 3807 manatees which is about 500 more than the previous record from 2001.

Manatee with calf

Experts do however say that it is too early to cheer and that one shouldn’t read too much into this as this year offered ideal conditions for spotting manatees. Cold temperatures made the manatees gather in warm clear waters around nuclear power plants and natural springs making them easy to spot. The previous record year 2001 – when about 1000 more manatees were counted than the year before and the year after – also offered similar conditions. It is important to remember that the count doesn’t reflect the actual number of manatees but rather a minimum number of manatees as not all of them can be found and counted.

Wildlife managers and manatee advocates do however call the number encouraging and say that it might indicate that the manatee population is slowly recovering as the number is higher then the numbers the previous record year. They say that the count supports population models suggesting manatees are increasing in Northwest Florida, along the Atlantic Coast and on the upper St. Johns River. Pat Rose, executive director of the “Save The Manatee Club” does however add that the numbers in Southwest Florida and the Everglades, home to about 40 percent of all manatees in Florida, are believed to be in continuing decline. Data on this region is however much more scare as it is hard to keep track on the animals in the dark waters found in this area.

Considering that scientists earlier estimated the manatee population in all of Florida to be below 1500 animals it can only be concluded that the conservation process have been a success and with 3807 animals it seems clear that the situation is much better than it once were, even if there still is much work to do to protect these gentle giants.

This story might be a few days old but is still of interest and as I haven’t been able to get to it sooner I decided to post about it today.

Indonesia will allow trawling in selected areas for the first time in 30 years, maritime ministry official Bambang Sutejo announced on January 15. Trawling will be allowed off four areas of Indonesia East Kalimantan province, despite concerns about overfishing.

“There will not be overfishing this time as we’re only allowing small boats to trawl, and it’s not allowed in other parts of Indonesia,” says Sutejo, adding that legalising trawling would help fight illegal trawlers.

According to Chalid Muhammad of the independent Green Institute, trawling has a destructive impact on the marine environment and will intensify the problem with overfishing in Indonesian waters. “The total amount of fish caught is getting smaller each day while their imports are getting bigger,” says Muhammad.

Muhammad also feels a legalization of trawling will embarrass Indonesia as it prepares to host the World Ocean Conference. “If the government allows this, Indonesia will have a weak standing during the World Ocean Conference as sustainable management of marine resources will be discussed,” Muhammad said. The World Ocean Conference is an international gathering of policymakers and scientists held in May 2009.

Kalimantan is the Indonesian portion of the island Borneo, the third largest island in the world, and is divided into four provinces: East Kalimantan, West Kalimantan, South Kalimantan, and Central Kalimantan.

What is trawling?

Trawling is a fishing practise where fishing boats tow long nets behind them. These nets do not only scoop up commercially valuable fish, but all sorts of marine life. Trawling is divided into bottom trawling and midwater trawling, depending on where in the water column the trawling takes place. Bottom trawling is especially harmful to marine environments since it can cause severe incidental damage to the sea bottoms and deep water coral reefs.