Sharks reproduce again in Dutch waters


This 2015 video is about a school shark caught as bycatch by a Dutch shrimp fishing ship. The shark was marked for research and released.

Translated from Dutch Vroege Vogels TV:

Dutch baby sharks

Thursday, June 23, 2016

For the first time it has been established that a shark species reproduces in Dutch waters. Researchers from Wageningen IMARES and Sportvisserij Netherlands write that in the Journal of Fish Biology.

It concerns the starry smooth-hound shark. In the Oosterschelde and the Zeeland Delta in recent years countless young have been seen. It is suspected that they were born in the North Sea. ..

The researchers suspect that school sharks, a much larger species, also reproduce in our waters. …

This week also a petition was launched to enforce better protection for sharks. Sign too, and check out the action page.

Which animals kill humans?


Lethal animals

Which animals kill humans? This picture proves once the absurdity of governmental shark-killing campaigns like in Australia.

Young shark saved by seal rehabilitation workers


The young Lauwersoog shark

Translated from Blik op nieuws in the Netherlands today:

This Wednesday a beached starry smooth-hound shark was found at the Hoek van Bant, Lauwersoog by employees of the Seal Rehabilitation Centre Pieterburen. In close consultation with Mark de Boer of Rotterdam Zoo the animal was helped back to sea again.

Rehabilitation coördinator Michael Bakker Paiva of the Seal Centre Pieterburen has a very special week: last Sunday, he assisted in the rescue of a harbour porpoise and today he found a beached starry smooth-hound shark. The centre staff were reacting to a report about a dead seal and found the shark in shallow water in the Hoek van Bant, near Lauwersoog.

They had to act quickly, as low tide was starting.

Directly they discussed that with Mark de Boer of Rotterdam Zoo, because if the shark had to be cared for then it would go to Rotterdam.

Fortunately things went well for the animal and with the assistance of biologist Sander van Dijk of the Seal Centre Pieterburen the fish was helped into a bucket of water. Then the animal was freed in deep and calm water near the port of Lauwersoog.

This was a young shark, 85 centimeter. An adult may be 180 centimeter.

Bull shark in Dutch lake?


In this 31 March 2016 video, a Dutch wildlife warden talks about the Kolkven lake in the Kampina nature reserve in North Brabant province. Recently, a photo was made of a shark‘s fin protruding out of the water there. Probably, a bull shark, a species often held in aquariums, has been freed in the lake after growing too big for the aquarium.

Stay tuned, the warden says.

However, it turned out to be an April Fools’ Day joke. So, a ´bullshit´ shark.

This video says about itself:

9 March 2015

This documentary looks at the bull shark (Carcharhinus leucas), also known as the Zambezi shark or, unofficially, as Zambi in Africa and Nicaragua shark in Nicaragua. It is a requiem shark commonly found worldwide in warm, shallow waters along coasts and in rivers. The bull shark is known for its aggressive nature, predilection for warm shallow water, and presence in brackish and freshwater systems including estuaries and rivers. This is the full bull shark documentary.

Bull sharks can thrive in both saltwater and freshwater and can travel far up rivers. They have even been known to travel as far up the Mississippi River as Illinois, although there have been few recorded freshwater attacks. They are probably responsible for the majority of near-shore shark attacks, including many attacks attributed to other species.

Unlike the river sharks of the genus Glyphis, bull sharks are not true freshwater sharks, despite their ability to survive in freshwater habitats.

Sharks’ social networks, new research


Sand tiger sharks' social networks

From the American Geophysical Union in the USA:

New research reveals surprising social networks of sharks

February 22, 2016

Although historically seen as solitary animals, new research being presented here shows sharks may have a more complex social structure than previously thought. Using tracking devices to trace the movements of individual animals in the open ocean, researchers found that Sand Tiger sharks form complex social networks that are typically seen in mammals but rarely observed in fish.

“Higher-order decision-making processes are often associated with mammals, or species that we think of as really smart – dolphins, elephants, or chimpanzees,” said Danielle Haulsee, a PhD candidate in oceanography at the University of Delaware in Lewes. “Our research shows that it is important for the scientific community to not rule out these types of behaviors in non-mammalian species, as behavior can often give us insight on how species interact with their ecosystems and how resources that humans depend on are distributed around the world.”

Sand Tiger , top predators that live in coastal waters off the Eastern United States, have experienced drastic population declines over the past several decades. Sand tigers are important regulators of but have been historically understudied, according to Haulsee.

In the summer, Sand Tigers congregate together in the shallow waters of the Delaware Bay, but little is known about their movements and how they interact with one another in the during the rest of the year, Haulsee said. Understanding how these sharks move and interact could help biologists better conserve this species and determine how vulnerable they are to human activities such as fishing and dredging.

Haulsee and her research team used acoustic tags to track the movements of over 300 individual Sand Tiger sharks and record shark-shark interactions over the course of a year. Previous studies have looked at shark interactions in laboratories or species contained in pens, but this the first study to record interactions for almost a year in free-swimming sharks, Haulsee said.

Initial data from two individual sharks show they encountered nearly 200 other sand tigers throughout the year, as well as several individuals from other shark species.

These sharks exhibit fission-fusion social behavior, meaning that the number of sharks in a group and the individuals that are part of the group change by location and time of year. Haulsee and her team found that groups of Sand Tigers stay together for certain times of the year and fall apart during other times. They also found that Sand Tigers re-encounter the same sharks throughout the year.

One surprise was a sudden lack of encounters with other Sand Tigers in the late winter and early spring, Haulsee said. Up until that point, both Sand Tigers were encountering other sharks regularly, but in the late winter, both seemed to enter a dispersal phase where they encountered very few other sharks. According to Haulsee, this could be related to other aspects of the sharks’ lives, such as mating and searching for food, which suggests that they could be performing a kind of social cost-benefit analysis.

Although this type of social behavior has been suggested in sharks before, the change in the group composition on an individual basis has not been documented in this way, according to Haulsee.

“If you’re living with a group, there could be some kind of protection or information sharing that comes with being in that group,” she said. “But if there’s a lot of competition for food resources or mating resources, then it’s not beneficial anymore to be in a group, and you might swim away from your group and go off on your own.”

Haulsee will be presenting initial data from the study today at the 2016 Ocean Sciences Meeting co-sponsored by the Association for the Sciences of Limnology and Oceanography, The Oceanography Society and the American Geophysical Union.

The researchers hope to use their results to answer questions about whether Sand Tigers form family groups or whether sharks of similar size and sex form distinct groupings. They also hope that defining critical locations where sharks congregate together will help build conservation plans to better protect this species.

“If we know where and when the population is grouped, we can focus on limiting human-induced disturbances in those times and places,” Haulsee said. “For example, if we know there are certain times and places where breeding females, or even more importantly the pregnant females, are aggregated together, we can devote resources into those areas to protect those sharks.”

Save sharks and rays, new initiative


This video is called The Secret World of Sharks and Rays – Nature Documentary.

From Wildlife Extra:

New global strategy to save sharks and rays

A group of international conservation organizations launched a new strategy today to combat the decline of sharks and closely related rays, while warning that the rays are even more threatened and less protected than the higher profile sharks.

The call for greater inclusion of rays in conservation action plans is part of “Global Priorities for Conserving Sharks and Rays: A 2015-2025 Strategy,” released today in conjunction with a Convention on Migratory Species (CMS) meeting on shark conservation currently underway in San José, Costa Rica.

While calling on countries across the globe to take urgently needed actions to conserve and rebuild vulnerable populations of both sharks and rays, the 10-year strategy document emphasizes that, as a group, rays – including skates, stingrays, sawfishes, guitarfishes and devil rays – should receive as much attention and investment as their better known relatives, the sharks.

The approximately 650 species of rays include shark-like rays, such as the critically endangered smalltooth sawfish and Brazilian guitarfish.

Overfishing due to under-management is the single most important threat to sharks and rays,” said WCS Sharks and Rays Coordinator Amie Bräutigam. “Improvements in fisheries management and expansion of conservation efforts – for rays in particular – form a major part of this new strategy.”

The global strategy was produced on the basis of extensive data analysis and synthesis by experts from Shark Advocates International, Shark Trust, TRAFFIC, Wildlife Conservation Society (WCS), and WWF, with technical guidance and input from the International Union for Conservation of Nature (IUCN) Shark Specialist Group. These organizations have partnered to implement this strategy through the Global Sharks and Rays Initiative.

“We are eager to share our global shark and ray conservation strategy with governments, and to discuss concrete steps toward the many shared goals that are ripe for action,” said Sonja Fordham, President of Shark Advocates International. “Although the challenges are daunting and many questions remain, the tools and resources are already sufficient to meet CMS obligations for protecting many endangered rays and limit the catch of many heavily fished sharks.”

Along with highlighting the need for more attention to rays, the strategy emphasizes that science-based limits on shark and ray fishing and trade are urgently needed to end overfishing and ensure sustainability.

“Some shark and ray populations are capable of supporting fisheries in the long term,” said Ali Hood, the Shark Trust’s Director of Conservation. “Sustainable use is a pragmatic approach to conservation, which values the natural world, the importance of livelihoods, the cultural significance of products, and the need to minimize waste through full utilization. It also requires a genuine commitment to science-based management of populations – a key objective of this global ten-year strategy.”

Glenn Sant, TRAFFIC’s Fisheries Programme Leader, cautioned: “Shark and ray protection measures are only as good as their actual implementation. Ensuring the traceability of fisheries products along the trade chain is essential to assess the effectiveness of any regulations and ultimately in bringing about real conservation benefits for the species affected.”

For shark and ray species listed under the Convention of Migratory Species, the authors have called on member countries to ensure that several key steps are taken in line with convention obligations, including: establishing strict national protections for all five endangered sawfish species and all manta and devil rays; and adopting national and regional fishing limits for heavily-fished, highly migratory sharks, such as mako, hammerhead, and thresher sharks.

Demand for shark fin in Asia has long been considered the major driver for the overfishing of sharks, but the strategy highlights recent findings that market demand for shark and ray meat is also significant, and on the rise.

“The volumes of shark and ray meat traded internationally have doubled since the 1990s and are now considered as important as shark fin in driving overfishing of these animals,” noted Andy Cornish, Shark and Ray Initiative Leader of WWF International. “Driving major reductions in the global demand for shark and ray fins and meat, the vast majority of which are currently from unsustainable and untraceable sources, is an integral part of the strategy.”

The strategy also emphasizes that nearly half of the world’s shark and ray species have been classified by the IUCN as “Data Deficient,” meaning that information is insufficient to assess the health of their populations, which can further hinder conservation action.

“Our analyses for the IUCN Red List of Threatened Species reveal a quarter of the world’s cartilaginous fishes as at risk of extinction. A major shift in effort is needed to prevent the extinction of 70 most endangered species – sawfishes, guitarfishes, wedgefishes, freshwater sharks and rays – and to clarify the conservation status and needs of the 600 Data Deficient and newly discovered species,” said IUCN SSG co-chairs Nick Dulvy and Colin Simpfendorfer.

The Global Sharks and Rays Initiative is supported in part by the John D. and Catherine T. MacArthur Foundation and the Leonardo DiCaprio Foundation.