Reach for the sky! Thresher sharks have been reported for their flying leaps out of the water, but that behavior is rarely captured. It’s also a treat to see the shark’s iridescence so clearly beneath the sunlight. I hope that remora enjoyed its unscheduled flight! Found via @ah360views on Instagram.
MASSIVE GREAT WHITE SHARK PALEO-NURSERY DISCOVERED IN CHILE
For the first time, researchers have discovered the first prehistoric nursery site for Great White Sharks(Carcharodon carcharias) from fossil beds in tthe arid coast of northern Chile.
Great white sharks give birth in essential habitats, where young reside and grow in a safe place, free of predators and with plenty food. According to Jaime Villafana (University of Vienna), who led the study, “our understanding about current breending ground of great white sharks is still very limited, and fossil-nurseries are completely unknown”, until now, with the first clues.
He and colleagues analyzed statistically fossil teeth, from the Pacific coast of Chile and Peru, and reconstucted the body size and distribution patterns of the great white sharks in the past, from 5 to 2 million years ago. They found a high percentage of young sharks, in northern Chile, where sexually mature animals were completely absent. According to researchers, this fossil-nursery was much warmer than today, in terms of water depth, this area is interpreted as a shallow marine environment, with abundance presence of invertebrate organism, as bigger animals as horn sharks and semiaquatic ground sloths. This old nursery area is located in what is now the port of Coquimbo, a city with nearly 500,000 inhabitants.
- Researchers used fossil teeth, the only record left by the sharks, and through a regression, they modeled the size of the sharks that inhabited the place.
The earliest-known fossils of the great white shark are about 16 million years old, and despite its importance as top predator, they are currently threatened with extinction. This discovery provides a better understanding of the evolutionary success of one of the largest top predator in today’s oceans and could contribute to the protection of current nursery areas found in areas of South Africa, California, Australia, the Mediterranean and North Atlantic.
Photo: Great white shark at Isla Guadalupe, Mexico, August 2006, photo by Terry Goss.
[Photo description: Main photo, Mature and healthy female white shark surrounded by a lot of small fishes. She is swimming below the water, but near the surface.
ENDANGERED SHARKS IN YOUR BEAUTY CARE AND PET FOOD
As apex predators, sharks play an important role in marine ecosystem by maintaining the species below them in the food chain and serving as an indicator for ocean health, however, due to human pressure, third of open ocean sharks are threatened with extinction. Now, a study recently published in Conservation Genetics shows some threatened species are used as a component in beauty care and pet food products.
Sharks are commonly traded for their fns to be used in different Asian countries as a soup delicacy. Nevertheless, shark meat trade has increased substantially in the last decade, while liver oil trade is still largely unknown.
Using molecular and genetic analysis, Diego Cardeñosa from Colombia Azul Foundation identified in most of the tested products an elasmobranch-based ingredients. Surprising, all products tested were not labeled as containing elasmobranch-based ingredients.
- Identified near threatened as endangered sharks species in this study. The Endangered shortfn mako shark, as the blue shark, scalloped hammerhead and blacktip shark are part of the list.
The researcher highlights the need for more labeling controls, since shark populations could benefit if consumers have the alternative to choose whether or not to purchase products containing threatened shark species in order to decrease the global demand.
Sadly, the study doesn’t mention any brand. All cosmetics contained squalene or squalane in the list of ingredientes, but none of them contained any label suggesting its source (i.e. plant or animal). In words of the researcher, all products tested for this study were not labeled as containing elasmobranch-based ingredients.
Same with pet food, these items were only labeled containing meat from unspecific categories such as “ocean fish” or “white fish”.
The Angelshark (Squatina squatina) typifies the fish most at risk of extinction: it grows to a large size and is cartilaginous, so it has characteristics which make it less resilient. Once common throughout Europe, it is now only found in the Canary Islands.
President Trump’s frequent trips during the winter to his Florida property, Mar-a-Lago, sparked protests from nearby residents, ethics watchdogs and some elected officials.
But here’s something that’s mostly escaped public attention: The trips are also bad for sharks.
Blacktip sharks are seen migrating along the southeast Florida coast. (Stephen M. Kajiura)
Granted, Trump has expressed his distaste for sharks more than once, so he probably wouldn’t lose sleep over disrupting research on the ocean’s top predator. On July 4, 2013, he fired off multiple tweets denigrating the ancient species, writing, “Sharks are last on my list — other than perhaps the losers and haters of the World!”
Stephen M. Kajiura, a professor of biological sciences at Florida Atlantic University, has conducted an aerial survey for the past seven years to record the abundance and migration patterns of blacktip sharks.
The aerial surveys involve a low flying plane that takes off from an airport included in the no-fly zone activated when President Trump is in Mar-a-Lago.
“He has no idea that he’s doing it, but it does mean a significant reduction,” Kajiura said, hastening to add that he’s “not complaining” but does believe it represents the first time there has been “a direct imposition on data collection by a visiting president.”
Because the president traveled to the property seven times over the course of his first 11 weeks in office, it reduced the number of surveys that the marine biologist could take during that period by one-third.
I spoke with Dr. Kajiura about these migrations after his presentation at Shark-Con, and this is definitely some interesting data. If you are interested in reading the most recently published results, you can access the paper here: Kajiura & Tellman, 2016.
Many species of catshark (family: Scyliorhinidae) lay eggs in tough egg cases known as mermaid’s purses. These cases have curly tendrils that tangle around objects to prevent them from floating away.
The gestation period of the egg can range from a few months to over a year, depending on the species and water temperature. If held against a light source, the developing embryo can easily be seem.
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