Dr Peter Gausmann

Dear friends and colleagues 🦈🌿 Soon I will delete my X/Twitter account because I'm not convinced of it anymore (yes, you're right, I don't like Elon). You will find me here: bsky.app/profile/peterg… Thanks for all of your contributions, discussions, and likes! 🙏🙏🙏

@JeremyBRoberts Never ever! 🦈😬

Let’s play, 'Swim, Done, or None!' I'll share a picture or video of a shark species, and you tell me if you have swum with it (Done), would swim with it (Swim), or wouldn’t swim with it (None). Today, it's the great white shark (Carcharodon carcharias).

Bull sharks are beautyful....and graceful....and lovely! 😍🐃🦈💙💙💙

@JeremyBRoberts D. 🍇⬜🦈

This shark is a: A. 🍋🦈 B. 🥉🐳🦈 C. 🇬🇱🦈 D. 🍇⬜🦈 E. 🍪👑🚀🦈

Probably, there are a few "rogue" shark individuals among the majority of harmless this new study of @ericclua found out....🦈

Bega Valley Shire NSW #No #Shark #Fishing

@JeremyBRoberts This blue shark has a very full belly....🦈🍽🐋😅

I hope you’ve had a nice morning, and a lovely breakfast. :)

@JeremyBRoberts 😊😊😊😊😊

How would you rate the smile of a zebra shark (Stegostoma fasciatum)? 😀🦈 With small, ridged teeth perfect for crushing shells, these gentle sharks are built for munching on mollusks and crustaceans. Rate it 1-5 smiles!

When we first started exploring Andros, we had hopes that we would see Hammerheads during the winter months, which we did! As we continued to go back, we started to see them throughout the entire year which was something we were not expecting! Since those early days we have been SPOT tagging these Hammerheads to see where they go. Our hope is to understand how these sharks are using Andros Island. Some have shown to stay all year round while others migrated to other Bahamas islands or up to the States. We have even been able to recapture some of these sharks years later! 〰〰〰 📸: @gbrllozada #shark #sharks #sharktagging #sharkresearch #savesharks #hammerhead #hammerheadshark #lovesharks #marinebiology #saltlife #sealife #ocean

@JeremyBRoberts B. 🐃🦈😬💙

Today’s shark is the Bull Shark (Carcharhinus leucas). But can you guess which set of teeth belongs to it? Clockwise from top right, the teeth are labeled A, B, and C. Which one do you think matches the Bull Shark?

@JeremyBRoberts A. 🇯🇵👼🦈

This shark is a: A. 🇯🇵👼🦈 B. 🧵🦈 C. 🥖👃7️⃣🦈 D. 🍣🦈 E. 🌮🎩🛴🦈

#JFB: Novel pre-copulatory behavior in basking sharks observed by drone doi.org/10.1111/jfb.15… #FishSci doi.org/10.1111/jfb.15…

@JeremyBRoberts GWS 🦈😉

Question tweet: Which shark doesn’t belong? •Bull shark •Lemon shark •Blue shark •Great white shark

@JeremyBRoberts Notorhynchus cepedianus 🦈💙

This shark is a: A. 🍋🦈 B. 🌊🔵🦈 C. 🥖👃7️⃣🦈 D. 🏖️🐅🦈 E. 🧶🎩🦉

Estimated between 4.5-5 meters this is by far the largest hammerhead we have ever caught, it is also highly likely a world record! 🤯   During summer 2024 our team were conducting our usual research when one of our lines was struck so hard it started to move the weight. Our team rushed over to find this GIGANTIC great hammerhead.   On arrival, the shark was moving differently, she was foul hooked and the team were unable to direct her in order to secure her for measuring and tagging. This hammerheads age and experience likely informed her the free food wasn’t quite worth the risk and so she spat the hook soon after taking it which resulted in it catching in her side. We use circle hooks which is likely why this happened. Although J hooks catch more animals, they cause more injuries such as gut hooking. Circle hooks typically reduce catch rates, but promote animal safety and wellbeing. We STRONGLY encourage all fishers to only use circle hooks!   After 10 minutes it was clear we were not going to secure her fast enough; she was ~1500 lbs and with the team unable to control her head the shark was able to put her entire weight on them. The decision was made to cut the line and set her free rather than persevering and risking her life - hammerheads suffer post release mortality e.g. death on release after long fights. We have preached for years that animal safety will ALWAYS be our priority and so cutting the line to ensure she lived rather than fighting her to confirm a measurement was an easy decision. We know our hooks rust out over time, however given the placement we believe this will fall out far sooner.   This shark is estimated between 4.5-5 meters based on reviewing extensive imagery putting her at approximately 50 years of age. Andros continues to surprise and impress us and is home to so many incredibly rare animals including sawfish, and hammerheads of this size. We have now seen and caught multiple 4 meter hammerheads which indicates Andros is probably a mating, or even pupping ground. We must continue to conduct research here to reveal more of the islands secrets. We have lots more work to do!   Thank you to all who support our work, we couldn’t make these discoveries without you!   📸: @annieguttridge   #greathammerhead #hammerhead #savingtheblue #sharkresearch

Let’s glide on the sea floor with a bull shark.

@JeremyBRoberts Under certain circumstances (clear water with good visability, non-baited) 😉🐃🦈💙

Let’s play, ‘Swim, Done, or None!’ I’ll share a picture or video of a shark species, and you tell me if you have swum with it (Done), would swim with it (Swim), or wouldn’t swim with it (None). Today, it’s the bull shark (Carcharhinus leucas).

@JeremyBRoberts The bull shark is a carcharhinid shark and all others (shortfin mako, salmon, and great white) are lamnid sharks/mackarel sharks 🦈😉

One of these sharks doesn’t belong! 🦈 Can you guess which one and why? Let me know your pick!

Not only human beings are loving sharks! 😄😅🦈💙🐶

@FeitosaManir Dear Leonardo, I think the old descriptibe work of Garrick (1982) "Sharks of the henus Carcharhinus" could contain such information (but also again for Carcharhinid family) 🦈 FishBase provides a PCL/TL calculator I think. Hope this was helpful 🙋‍♂️

#shark peeps! Anyone know of any papers estimating fin-length to total-length relationships at least at the family level? Found 2 today but heavily biased towards Carcharhinus as usual… precaudal-length not useful (unless there’s a PCL to TL relationship too)