Shark beaches alive on Vlieland island


This video from South Africa says about itself:

Dylan Irion, Swimming Behaviour of the Common Smoothhound Based on Accelerometer Data

A thorough understanding of the behaviour and habitat use of sharks is critical for improving our understanding of the movement ecology and thus the effective conservation of these threatened species. Direct observation of sharks is often difficult to accomplish in the marine environment where access to free-swimming individuals can be restricted by numerous factors.

The miniaturisation and reduced costs of producing sensors for bio-logging has provided several solutions to overcome this obstacle. The accelerometer is a sensor that functions by recording changes in acceleration due to the dynamic motion of a body, and the static acceleration caused by gravity.

In this study I demonstrate the potential for utilising tri-axial accelerometry as a method for characterising the movement of sharks. By attaching accelerometers to captive common smoothhound sharks (Mustelus mustelus) and comparing the accelerometer record to visual observations of their behaviour, I was able to detect tail beat frequency, tail beat amplitude, and body posture.

Translated from NOS TV in the Netherlands:

Shark strands alive on Vlieland

Update: Monday 24 Feb 2014, 13:48

On Vlieland, a living shark, more than a meter in size, has beached. Never before such a large shark had washed up [alive] on the Dutch coast. It is a starry smooth-hound shark normally only found in warmer seas.

Hikers found the exhausted shark yesterday on the beach. The fish is injured on its muzzle. It was put back into the sea, but kept beaching again and again. That’s why people brought it to the aquarium in the nature center De Noordwester on Vlieland.

The starry smooth-hound shark is not dangerous to humans. It has no teeth and only eats crustaceans such as shrimps.

According to Dutch daily Algemeen Dagblad, the shark shows signs of recovery.

See also here.

Sharks beaches on Vlieland: here.

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Devonian era animals and plants


This video is called Devonian forest.

From LiveScience:

Devonian Period: Climate, Animals & Plants

By Mary Bagley, Live Science Contributor

February 22, 2014 03:46am ET

The Devonian Period occurred from 416 million to 358 million years ago. It was the fourth period of the Paleozoic Era. It was preceded by the Silurian Period and followed by the Carboniferous Period. It is often known as the “Age of Fishes,” although significant events also happened in the evolution of plants, the first insects and other animals.

Climate and geography

The supercontinent Gondwana occupied most of the Southern Hemisphere, although it began significant northerly drift during the Devonian Period. Eventually, by the later Permian Period, this drift would lead to collision with the equatorial continent known as Euramerica, forming Pangaea.

The mountain building of the Caledonian Orogeny, a collision between Euramerica and the smaller northern continent of Siberia, continued in what would later be Great Britain, the northern Appalachians and the Nordic mountains. Rapid erosion of these mountains contributed large amounts of sediment to lowlands and shallow ocean basins.  Sea levels were high with much of western North America under water. Climate of the continental interior regions was very warm during the Devonian Period and generally quite dry.

Marine life

The Devonian Period was a time of extensive reef building in the shallow water that surrounded each continent and separated Gondwana from Euramerica. Reef ecosystems contained numerous brachiopods, still numerous trilobites, tabulate and horn corals. Placoderms (the armored fishes) underwent wide diversification and became the dominant marine predators. Placoderms had simple jaws but not true teeth.  Instead, their mouths contained bony structures used to crush or shear prey. Some Placoderms were up to 33 feet (10 meters) in length. Cartilaginous fish such as sharks and rays were common by the late Devonian. Devonian strata also contain the first fossil ammonites.

By the mid-Devonian, the fossil record shows evidence that there were two new groups of fish that had true bones, teeth, swim bladders and gills. The Ray-finned fish were the ancestors of most modern fish. Like modern fish, their paired pelvic and pectoral fins were supported by several long thin bones powered by muscles largely within the trunk. The Lobe-finned fish were more common during the Devonian than the Ray fins, but largely died out. (The coelacanth and a few species of lungfish are the only Lobe-finned fishes left today.) Lobe-finned fishes had fleshy pectoral and pelvic fins articulating to the shoulder or pelvis by a single bone (humerus or femur), which was powered by muscles within the fin itself. Some species were capable of breathing air through spiracles in the skull. Lobe-finned fishes are the accepted ancestors of all tetrapods.

Plants

Plants, which had begun colonizing the land during the Silurian Period, continued to make evolutionary progress during the Devonian. Lycophytes, horsetails and ferns grew to large sizes and formed Earth’s first forests.  By the end of the Devonian, progymnosperms such as Archaeopteris were the first successful trees. Archaeopteris could grow up to 98 feet (30 meters) tall with a trunk diameter of more than 3 feet. It had a softwood trunk similar to modern conifers that grew in sequential rings. It did not have true leaves but fern-like structures connected directly to the branches (lacking the stems of true leaves). There is evidence that they were deciduous, as the most common fossils are shed branches. Reproduction was by male and female spores that are accepted as being the precursors to seed-bearing plants. By the end of the Devonian Period, the proliferation of plants increased the oxygen content of the atmosphere considerably, which was important for development of terrestrial animals. At the same time carbon dioxide (CO2), a greenhouse gas, was depleted from earlier levels. This may have contributed to the cooling climate and the extinction event at the end of the Devonian.

Animals

Arthropod fossils are concurrent with the earliest plant fossils of the Silurian. Millipedes, centipedes and arachnids continued to diversify during the Devonian Period. The earliest known insect, Rhyniella praecusor, was a flightless hexapod with antennae and a segmented body. Fossil Rhyniella are between 412 million and 391 million years old.

Early tetrapods probably evolved from lobe-finned fishes able to use their muscular fins to take advantage of the predator-free and food-rich environment of the new wetland ecosystems. The earliest known tetrapod is Tiktaalik rosae. Dated from the mid-Devonian, this fossil creature is considered to be the link between the lobe-finned fishes and early amphibians. Tiktaalik was probably mostly aquatic, “walking” on the bottom of shallow water estuaries. It had a fish-like pelvis, but its hind limbs were larger and stronger than those in front, suggesting it was able to propel itself outside of an aquatic environment.  It had a crocodile-like head, a moveable neck, and nostrils for breathing air.

Mass extinction

The close of the Devonian Period is considered to be the second of the “big five” mass extinction events of Earth’s history. Rather than a single event, it is known to have had at least two prolonged episodes of species depletion and several shorter periods. The Kellwasser Event of the late middle Devonian was largely responsible for the demise of the great coral reefs, the jawless fishes and the trilobites. The Hangeberg Event at the Devonian/Carboniferous Boundary killed the Placoderms and most of the early ammonites. Causes of the extinction are debated but may be related to cooling climate from CO2 depletion caused by the first forests. Although up to 70 percent of invertebrate species died, terrestrial plants and animals were largely unaffected by these extinction events.

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Dutch brook lamprey mating season


This video is about the Dutch brook lamprey mating season.

Because of the mild weather this winter, brook lampreys have started mating weeks earlier than usually.

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Galapagos islands tiger sharks, new research


This video is called Expedition Galápagos: Tiger Sharks.

Press release from OCEARCH:

First Tiger sharks in history of Galapagos Islands tagged

Wednesday, 19 February 2014, 10:53 am

First Tiger sharks in history of Galapagos Islands tagged, including 4-meter female named Yolanda captured in Canal de Itabaca – 66 fish, 8 species tagged in total

The Galapagos National Park Directorate, Charles Darwin Foundation (CDF), Turtle Island Restoration Network (TIRN) and the University of Massachusetts Dartmouth collaborated with OCEARCH to complete its 18th global expedition – conducted in one of the world’s treasured marine resources, the Galapagos Islands. According to OCEARCH collaborating lead scientist and Science Director of TIRN,Dr. Alex Hearn: “We brought together a multidisciplinary team of scientists and the foremost marine megafauna explorers. We made use of the world’s only oceanic research lift platform, which allowed us to handle large sharks with a minimal amount of stress. Our research, which uses methods approved by the IACUC Animal Care Committee while I was a Project Scientist at UC Davis, and by the Galapagos National Park Directorate, accomplished so much in so little time – over 66 individuals and 8 species caught, tagged and released. We have spent years working towards this study – making the leap from a shark movement study to one of the entire pelagic assemblage.”

The first Tiger sharks in the history of the Galapagos Islands were tagged and studied, including a large 4 meter female that was captured in a canal where a Navy diver had been working was concerned with its presence. The shark was named after Yolanda Kakabadse Navarro, aunt of Pablo Navarro, an employee of Caterpillar, the primary sponsor of the expedition and OCEARCH. Yolanda is the current president of the World Wide Fund for Nature International (WWF), the former Minister of Environment for the government of Ecuador and the former president of the International Union for Conservation of Nature (IUCN). She also founded the Fundación Natura in Quito and the Fundación Futuro Latinoamericano. Yolanda has dedicated her life and career to protection and awareness of the environment and environmental issues, not only in Ecuador, but worldwide.

“Tiger sharks are incredibly impressive animals, and I am excited to share my name with one. There have been serious population declines in some areas due to fishing for their fins for shark fin soup, which sadly is still seen as a delicacy in many places,” said Yolanda Kakabadse, President, WWF International. “Tiger sharks undertake incredible journeys, about which we still know remarkably little – so this tagging project will help provide crucial information for conserving these magnificent animals.”

Dr. Hearn described the discovery of the Tiger sharks after capturing tagging and releasing 27 other sharks: “Just before the end of our trip, we were approached by a concerned member of the Ecuadorian Navy to ask for help with a large tiger shark that they were frequently encountering whilst doing dive maintenance work. Thanks to this conversation, the Navy gave us permission to attempt to catch and tag the shark. We ended up catching all four of our tagged Tiger sharks at this site. From a perceived threat, these sharks became overnight conservation icons for the Galapagos community, and their movements will be followed simultaneously by the Navy divers, local schoolchildren, the National Park officials who witnessed the tagging, and the scientists involved in the study.”

“This is an important project for the management of the Galapagos Marine Reserve because of the immediate scope of migration data on individuals and aggregations of shark species,” said Arturo Izurieta, Director of the Galapagos National Park. “It’s a project that has been strengthened in recent years with contributions from conservation partners such as Charles Darwin Foundation, OCEARCH and the Ministry of Environment of Ecuador leading the process of generation of information applied to management.”

Hearn was pleased with the breadth of species: “In all 31 sharks were captured, tagged, sampled and released including 4 Tiger, 8 Hammerhead, 9 Silky and 10 Blacktip sharks. A total of 35 bony fishes were captured, tagged, sampled and released including 5 Yellowfin Tuna, 10 Wahoo, 10 Skipjack and 10 Rainbow Runners. This huge sample of open water fish from across the food chain will help us understand how marine protected areas around oceanic islands contribute to the conservation of the open water species assemblage as a whole.”

Swen Lorenz, Executive Director for the Charles Darwin Foundation attributed the success to collaboration and previously unavailable capacity: “The combination of CDF’s scientific knowledge and OCEARCH’s capacity to capture, handle and release large mature animals resulted in an extremely successful expedition where 100% of the research goals were achieved.” More detail from Swen on the expedition can be found on his blog post “Tagging a Tiger in the World’s Most Pristine Tropical Archipelago”.

Expedition Leader and Founding Chairman for OCEARCH, Chris Fischer commented: “We came here to serve the ocean, Ecuador and its people, the scientists and the Galapagos National Park. I am proud of the endurance and tenacity our team demonstrated. Furthermore, a shark that would have likely been targeted and killed as a nuisance or threat was instead tagged with multiple technologies so public safety officials, local residents and the science team can track its movements in near real time. The fear of the unknown is a powerful negative force that we hope to remove by replacing that fear with the facts.”

Dr. Pelayo Salinas de León of the Charles Darwin Foundation summed up the expedition: “Being able to work with Chris and all the OCEARCH team has been a unique experience and has allowed us to achieve all our research goals. Satellite and acoustic tagging the first adult tiger sharks and large Yellow Fin Tunas in the Galapagos Marine Reserve was a lifetime experience and it was only possible thanks to the OCEARCH unique platform. Thanks to this expedition we will be able to track the movements of these apex predators for the next 10 years to come. This research will provide very valuable information to further understanding our knowledge on the ecology of these key species and to inform the Galapagos National Park management plans. Also, we will obtain very accurate data on the regional migratory patterns of these species and this information will be very valuable to promote regional conservation actions through initiatives like the Eastern Tropical Pacific Corridor.”

David Acuña Marrero of CDF added: “OCEARCH has provided us with the best possible resources in the world to tag sharks: the most experienced and proactive team in shark’s handling and tagging, in a boat that performs perfect for this purpose. OCEARCH’s platform makes handling and tagging big sharks an ‘easy’ task, as we saw ourselves the last day of the expedition tagging a 4m beautiful tiger shark.”

Heather Marshall of UMass Dartmouth, working to collect blood samples for Dr. Greg Skomal of the MA Marine Fisheries for the study of stress physiology, said: “I was pleased to see, from initial analysis in the field, that stress indicators were not significantly exacerbated throughout the tagging process. Indeed, when the sharks were released, their stress response looked low across the board based on the initial data.”

“We envisage a series of peer reviewed publications arising from this research, including regional analyses of movement patterns of Silky and Tiger sharks using data previously collected on OCEARCH expeditions at Cocos Island, Costa Rica in 2011 and at the Revillagigedos Islands, Mexico in 2010. The science team expects to present its results at relevant international conferences, including the American Elasmobranch Society meeting in 2015”, adds Dr. Hearn.

Enabling local scientists to perform fieldwork is an important part of the OCEARCH mission. The organization is working closely with the Galapagos National Park Directorate, Charles Darwin Foundation (CDF) and Turtle Island Restoration Network (TIRN) in every step – from planning to execution and data analysis. Ecuador is a member of the Permanent Commission for the South Pacific – a regional agency tasked with developing a regional Plan of Action for Sharks that integrates national plans, with a focus on transboundary species. The research team is part of a regional network (http://www.migramar.org), which has a seat on the CPPS Shark Committee. All relevant results and ensuing recommendations will be presented at meetings of this Committee and used in the development of the regional Plan of Action.

Outreach and education were core components of the expedition. Chris Fischer and the science team spoke at 2 local schools and 2 sharks were named after the schools: Oswaldo Guayasamin and Tomas de Berlanga, so they had their own sharks to follow. Tomas de Berlanga, Bishop of Panama, is credited with discovering Galapagos Islands in 1535. Oswaldo Guayasamin, Ecuador’s most famous painter and sculptor was a voice for the poor and dispossessed in Latin America, and received the UNESCO International Jose Marti Prize after his death in 1999.

The Global Shark Tracker is a web-based near real time satellite tracking tool for sharks that will eventually be expanded to other species. …

To stay updated on the daily activities, visit www.OCEARCH.org where you can see the daily Expedition Blog, experience the Global Shark Tracker and see all social media links.

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Valentine’s Day for animals


This video is called Valentine’s Day Animals: Compilation.

From eNature blog in the USA:

Valentine’s Day In The Wild— There’s A Lot Going On Out There!

Posted on Wednesday, February 13, 2013 by eNature

Some folks love it, others dread it. But no matter what your feelings about Valentine’s Day, there’s no avoiding it.

And it’s not just humans— animals in the wild are succumbing to Cupid’s arrows as well.

Take a a walk through your backyard or a backcountry hike and you’ll likely be confronted by a courtship ritual of some sort. For the animals engaged in such displays, though, the whole month of February, not just Valentine’s Day, is meant for romance.

Despite the chill that remains in much of North America, Raccoons, Minks, river otters, Gray and Red Foxes, Coyotes, and skunks all take time off from their mid-winter hunting to prowl for partners. Groundhogs start to look around longingly soon after they emerge from their long winter’s sleep, and many of their rodent kin, from California Kangaroo Rats to Black-tailed Prairie Dogs, also consider February just the right time for rubbing noses.

Birds, too, at least a few of them, hit their romantic stride during the second month of the year. Great Horned Owls start hooting it up in December but mostly wait till now to take care of their romantic business. Male Red-winged Blackbirds return to much of the continent in February and start right in displaying and singing for prospective females, while American Woodcocks stage their delightfully bizarre courtship performances in the February twilight. And in the swamps of southern Florida, ungainly looking Wood Storks make hay in the February sunshine.

Also out under bright sunny southern skies are myriad butterflies looking for love. There are large Pipevine Swallowtails and diminutive Western Pygmy-Blues in Texas, gorgeous Zebra Heliconians and Gulf Fritillaries in Florida, Spring Azures and Long-tailed Skippers in the other Gulf States, and dainty Desert Marbles and Desert Orangetips in the Southwest. Wherever and whenever you see butterflies flying, even in February, you can rest assured that half of them are males on the lookout for lepidopteran love.

As for amphibians, their amorous inspiration comes in the form of a nice February rain. And when the rain falls, the amphibians emerge from their hibernation and march straight to breeding pools. Pond frogs, treefrogs, toads, and salamanders of all kinds take to the mating trail in February in the southern parts of the United States. The male frogs are at their vociferous best in their choruses to attract mates, while male salamanders vie for partners, too, though without the audible fanfare.

Even fish feel frisky these days, especially the Rainbow Trout in the Smokies and the Largemouth Bass in Texas. The same is true for animals in saltier waters: Humpback Whales, Northern Right Whales, Gray Seals, and Northern Elephant Seals have love on their marine-mammal minds, while far to the north in the pitch-black darkness of the Arctic winter Walruses have a gleam in their eyes.

Environmentalists’ Valentines Day Wish: Stop Selling Bee-Harming Plants: here.

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Big pro-shark demonstrations in Australia


This video is called SAVE OUR SHARKS! Massive Protest On Australian Beach After Government Calls For Shark Cull.

From AFP news agency today:

Thousands rally against shark cull in Australia

1 hour ago

Thousands of people rallied across Australia Saturday against a controversial shark culling policy designed to prevent attacks, saying killing the marine animals was the not the answer.

The controversial policy to catch and kill sharks off popular west coast beaches was given the green light last month after six fatal attacks in the past two years.

It is aimed at reducing the risks to water users and allows baited drum lines with hooks designed to capture large sharks to be set one kilometre (0.62 miles) offshore at busy Western Australian beaches for a trial period until April 30.

Any shark longer than three metres (10 feet) snagged by the lines and deemed to be a threat—including great white, bull and tiger sharks—will be destroyed, with the first casualty reported last week.

The move has angered conservationists and rallies were held at sites around the country, including at least 2,000 people at Manly Beach in Sydney and 6,000 expected at Cottesloe Beach in Perth.

Opponents claim the trial flies in the face of international obligations to protect the great white shark.

Anthony Joyce, who was attacked by a shark off a Sydney beach last October, once shared the Western Australian government’s views on culling the animals, but after doing extensive research he now disagrees.

“The amount of sharks they are going to kill is going to make no difference in the scheme of things,” he told reporters at Manly.

After speaking with shark experts and marine biologists, he now believes greater government support for marine biology programmes and shark education in schools is the way to go.

Another protestor in Manly, Katherine Cook, said she was outraged at the shark killings.

“I’m really angry and incensed that we can’t co-exist with anything,” she said.

“We are going into their (sharks) environment. Why can’t we co-exist?”

At Cottesloe, a female activist chained herself to a fisheries boat to prevent it leaving to set and monitor baited hooks off the coast, the ABC reported.

While sharks are common in Australian waters, deadly attacks are rare, with only one of the average 15 incidents a year typically proving fatal.

In first 3 weeks of West Australia shark cull, majority of sharks caught were still undersized: here.

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