LOST BEFORE FOUND: NEW SHARK SPECIES LIKELY  EXTINCT DUE TO INTENSIVE FISHING

Using three preserved specimen caught in the 1930s from Broneo, Thailand and Vietnam, researchers experts in sharks have described a new species of whaler shark from the Western Central Pacific known only from historic records. Since this shark has not been since 1934, is likely now extinct.

The historic range of the lost shark (Carcharhinus obsolerus), as is proposed to be named, is currently under intense fishing pressure and this species has not been recorded anywhere in over 80 years. It lived in coastar waters along the western Central Pacific.

The specific name “obsolerus” is Latin for Extinct, in allusion to the fact that the species has not been seen in decades.  According to the study where this species is described, with so few known records, there is a possibility it has been lost from the marine environment before any understanding could be gained of its full historic distribution, biology, ecosystem role, and importance in local fisheries.

- Illustration of lateral view of Carcharhinus obsolerus. Painting by Lindsay Marshall

Whaler sharks are one of the most economically important groups for the various shark fisheries that exist around the world. Also, they are found as  bycatch of other commercial fisheries across its range, which cointributes to dimishes its populations, which contributes to diminishes its populations.

• Imagen:  Preserved specimen of Carcharhinus obsolerus.
  
• Reference: White et al., 2019.  Lost before found: A new species of whaler shark Carcharhinus obsolerus from the Western Central Pacific known only from historic records. PlosOne
  

[Photo description: Close up of the head and a photograph of the whole shark, showing typical features found in sharks.]

todropscience:

ZINERD is a  collaborative science zine, in Spanish, available for free download, and if you feel it, you can do your own science zine and upload to www.zinerd.org.

• please, follow facebook.com/holazinerd
  
• and instagram.com/holazinerd/
  

ZINERD es un fanzine de ciencia en español,  disponibles para descarga gratuita, donde cubrimos diferentes temas, y si lo siente, puede hacer su propia publicación de ciencia y subirla a www.zinerd.org, así crearemos una biblioteca de fanzines de ciencia en español.

ZINERD is a  collaborative science zine, in Spanish, available for free download, and if you feel it, you can do your own science zine and upload to www.zinerd.org.

• please, follow facebook.com/holazinerd
  
• and instagram.com/holazinerd/
  

ZINERD es un fanzine de ciencia en español,  disponibles para descarga gratuita, donde cubrimos diferentes temas, y si lo siente, puede hacer su propia publicación de ciencia y subirla a www.zinerd.org, así crearemos una biblioteca de fanzines de ciencia en español.

todropscience:

These are ossicles, small calcareous elements embedded in the skin of the snake sea cucumber (Synapta sp).  Ossicles are embedded in the dermis of the body wall of echinoderms, such sea cucumbers, sea stars, brittle stars, and sea urchins. They form part of the endoskeleton and provide rigidity and protection. These small structures varying in shape, size, and in number, depending on the species.

• Photo: Sea-cucumber skin by Christian Gautier,  Nikon Small World Photomicrography Competition
  

These are ossicles, small calcareous elements embedded in the skin of the snake sea cucumber (Synapta sp).  Ossicles are embedded in the dermis of the body wall of echinoderms, such sea cucumbers, sea stars, brittle stars, and sea urchins. They form part of the endoskeleton and provide rigidity and protection. These small structures varying in shape, size, and in number, depending on the species.

• Photo: Sea-cucumber skin by Christian Gautier,  Nikon Small World Photomicrography Competition
  

This tiny shark is Error Seamount Catshark (Bythaelurus stewarti), a new deep-water catshark species, described based on specimens caught on the Error Seamount (Mount Error Guyot) in the northwestern Indian Ocean. The new species differs from all congeners in the restricted distribution, a higher spiral valve turn count and in the morphology of the dermal denticles.

- Adult male, 425 mm total length, in lateral, dorsal, and ventral views.

The Error Seamount Catshark is known only from the Error Seamount, in 380–420 m depth. It is apparently a microendemic species restricted to this isolated Seamount. Probably due to a speciation process, potentially driven by special environmental conditions and prey availability on the seamount. The assumption of the presence of an isolated population of Bythaelurus catsharks on the Error Seamount is supported by the fact that high levels of endemism are generally assumed for seamounts.

• Reference (Open Access): Weigmann et al., 2018. A new microendemic species of the deep-water catshark genus Bythaelurus (Carcharhiniformes, Pentanchidae) from the northwestern Indian Ocean, with investigations of its feeding ecology, generic review and identification key. PLoS ONE.
  

todropscience:

MICROPLASTIC POLLUTING THE MOST DEEPEST PART OF THE OCEAN

Millions of metric tons of plastics are produced annually and transported from land to the oceans. New evidence show microplastics is accumulating in the deepest reaches of the ocean, one liter of water from the Mariana Trench contains thousands of tiny plastic pieces, the finding are published in   Geochemical Perspectives.

The Mariana Trench is the deepest place on Earth, deeper than the height of Mount Everest above sea level. But marine debris is not new there, early this year, a study commented that in 1998, japaneses recorded a plastic bag on the sea bottom, at 10,898 m in the Mariana Trench, observed by ROV KAIKO. 

In the Mariana Trench’s most polluted regions, reseachers found as many as 2,000 pieces of microplastic in one liter. 

At the Hausgarten Observatory,  in the Arctic Greenland Sea to the west of Svalbard, researchers sampled at 5,400 m, and found as much as 3,400 pieces of microplastic in one liter.

The hadal zone also known as the hadopelagic zone, is the deepest region of the ocean lying within oceanic trenches. Microplastic abundances in hadal bottom waters range from 2 to 13  pieces per litre, several times higher than those in open ocean subsurface water. Moreover, microplastic abundances in hadal sediments of the Mariana Trench vary from 200 to 2200 pieces per litre, distinctly higher than those in most deep sea sediments. Manmade plastics have contaminated the most remote and deepest places on the planet. The hadal zone is likely one of the largest sinks for microplastic debris on Earth, with unknown but potentially damaging impacts on this fragile ecosystem. 

• Photo:  Examples of microplastics in sediment samples,  scale bar 0.2 mm. 
  
• Reference: Peng et al., 2018. Microplastics contaminate the deepest part of the world’s ocean. Geochemical Perspectives

[Imagen description: Fiber clothes, and tiny fragments of plastic found in the marine sediment. They have varied shapes and colors, all measuring around one millimeter or less.]

wtf-scientific-papers:

Chiou and Bergey (2018)

(Zoom waaaay in on their figure 1)

is this real? I zoomed but no trump in the figure 1 I CAnt believeee it!! 

Good news in conservation: A pair of Madeiran storm petrel (Oceanodroma castro) nested for the first time in Berlenga Island, off Peniche coast, Portugual, following the conservationist effort for eradicating its predator, the black rat.  

Only one of the 20 artificial nests that project LIFE Berlengas team installed for Madeiran storm petrel has one egg, it sounds not big, but it is the result of a lot of effort.. Hopefully this egg will hatch by January. Until today there were no records of this species nesting in the island, only in nearby islets.

Artificial nests are made of ceramic vases, slightly buried on the ground, with a hole for birds to come in and out.

To help attract nesting pairs, LIFE Berlengas team also installed a system that reproduced typical sounds of a Madeiran storm petrel colony. Also in each nest the team placed a cloth bag used in previous ringing campaigns of this species, since Madeiran storm petrels have a very strong and characteristic smell. 

• Photo: Madeiran storm petrel, by Pedro Geraldes.
  
• more at  wilder

[Photo description: A Madeiran storm petrel resting on a rock. These seabirds are adapted to touch land only during breeding season. So its position when resting look a little clumsy on the ground.]

MICROPLASTIC POLLUTING THE MOST DEEPEST PART OF THE OCEAN

Millions of metric tons of plastics are produced annually and transported from land to the oceans. New evidence show microplastics is accumulating in the deepest reaches of the ocean, one liter of water from the Mariana Trench contains thousands of tiny plastic pieces, the finding are published in   Geochemical Perspectives.

The Mariana Trench is the deepest place on Earth, deeper than the height of Mount Everest above sea level. But marine debris is not new there, early this year, a study commented that in 1998, japaneses recorded a plastic bag on the sea bottom, at 10,898 m in the Mariana Trench, observed by ROV KAIKO. 

In the Mariana Trench’s most polluted regions, reseachers found as many as 2,000 pieces of microplastic in one liter. 

At the Hausgarten Observatory,  in the Arctic Greenland Sea to the west of Svalbard, researchers sampled at 5,400 m, and found as much as 3,400 pieces of microplastic in one liter.

The hadal zone also known as the hadopelagic zone, is the deepest region of the ocean lying within oceanic trenches. Microplastic abundances in hadal bottom waters range from 2 to 13  pieces per litre, several times higher than those in open ocean subsurface water. Moreover, microplastic abundances in hadal sediments of the Mariana Trench vary from 200 to 2200 pieces per litre, distinctly higher than those in most deep sea sediments. Manmade plastics have contaminated the most remote and deepest places on the planet. The hadal zone is likely one of the largest sinks for microplastic debris on Earth, with unknown but potentially damaging impacts on this fragile ecosystem. 

• Photo:  Examples of microplastics in sediment samples,  scale bar 0.2 mm. 
  
• Reference: Peng et al., 2018. Microplastics contaminate the deepest part of the world’s ocean. Geochemical Perspectives

[Imagen description: Fiber clothes, and tiny fragments of plastic found in the marine sediment. They have varied shapes and colors, all measuring around one millimeter or less.]