#shark behavior

[hyruleairbnb]

Exploration bites

Sidon wonders if he tastes like rock but yunobo doesn’t like

[baddawgsports]

🦈 BREAKING: Baby great whites are thriving in NYC waters! Here's why this discovery is amazing news for ocean health (and why you shouldn't be scared) 🌊 #SharkConservation #NYCWildlife

The Hidden Nursery: How Baby Great White Sharks Are Revitalizing New York's Marine Ecosystem

[wholesome-sharks]

Tassled wobbegong shark with the end of its tail curled, Raja Ampat (source)

I DIDN'T KNOW THEY COULD DO THAT!!!!!

[originaljediinjeans]

Sharks are not known for being good at running in running wheels. Or hopping from one perch to the other in a birdcage. Which is why, unlike hamsters or sparrows, sharks were never a very popular laboratory model for circadian research.

So I’m in the middle of a bad spell of insomnia, and I was rewatching a video of Jackson Galaxy helping out a cat with sleeping problems, and then I wondered, “Do sharks produce melatonin when they rest?” 

Sharks don’t actually ‘sleep’ like mammals do, but when they rest they either slow down and cruise (for RAM-obligate/pelagic/open ocean sharks), or they will sit on the ocean floor and enter a relaxed state (benthic/buccal-pumping sharks), It’s kind of confusing because they don’t close their eyes, as their nictitating membranes are for safety purposes. (LINK) This NatGeo Wild video explains it a little more clearly. 

Both classes of sharks take advantage of the current to help them breathe while in resting state. There is a cave off the coast of Mexico where Caribbean reef sharks (RAM-obligate breathers) are known to actually rest on the cave floor in a position where the current will flow through their gills. 

The Scientific American article I linked above (from 2013) reviews several studies that gathered data about circadian rhythm in sharks across a number of species. Melatonin is only mentioned explicitly for one but it is implied that it is a chemical that contributes to the resting state of sharks, as with sleep in other animals. 

Let me reiterate, I’m only an amateur shark enthusiast. If you’re from Science Tumblr and want to add any corrections or insights feel free. 

(warning: some of the shark videos I have linked above may leave you feeling a little [YAWN] drowsy)

[why-animals-do-the-thing]

Nicholas Wu on Twitter

“Great hammerhead sharks spend 90% of time swimming on their side to reduce transport costs. By @nicklpayne https://t.co/UjjT1ym0SN https://t.co/bbpJftg2O8”

Welcome to Theme Day: “Cool new animal science my journalist friend told me I should blog about” as chosen by my Patreon supporters! Next up is a bit of science that admittedly was not sent to me by this journalist friend, but I’m 99.9% sure if she’d seen it before I did it would have ended up in my inbox. 

Basically, the largest species of hammerhead sharks (great hammerheads are the ones that can get up to 20 feet long) have figured out how to use less energy by swimming while rolled over onto their side to reduce drag. This was determined by sticking accellerometers and video cameras onto a number of sharks in the Bahamas and pretty much watching the weird stuff they did... like spend all of their time tilted  50 to 75 degrees to one side. They also switched which side they were tilted towards about every ten minutes. 

I attached the link to the tweet where I first saw this study, because I think the GIF posted there is much easier to watch than the video embedded in the NewScience article announcing the discovery. This paper is open-access as well, so if you’re wanting to dig into the biomechanics of shark swimming, you can absolutely do that. 

[regularshark]

My favorite part about going to the grocery store:

[letslearnanything]

How to Dive with Sharks in South Africa

Diving with sharks in South Africa is an exhilarating experience that combines adventure, education, and conservation in a unique marine setting. This course is designed to guide you through everything from selecting reputable dive operators and preparing for your dive, to understanding how to safely and respectfully interact with sharks in their natural habitat. Whether… Read More »How to Dive with Sharks in South Africa

Ever dreamed of diving with sharks in South Africa? 🦈🌊 Dive into our latest guide on Let's Learn Anything that covers everything you need to know for a safe, respectful, and unforgettable underwater adventure! Get up-close with majestic creatures, learn about conservation efforts, and prepare yourself with essential tips. Your once-in-a-lifetime experience starts here - don't miss out on this thrilling adventure! #SharkDiving #AdventureTravel #MarineConservation

[beatriceportinari]

Went swimming despite the wind water was pretty cold but nice nonetheless #noragrets