Have you ever thought about how old a shark can live to be? so have we... the truth is, there is so much we don’t know about sharks, and “age” is one of those grey areas. scientists have been trying to come up with a concrete methodology to determining a shark’s age for decades, but unfortunately, there has been no accurate solution to this. the problem lies in a shark’s anatomy. researchers have tried tagging, but tags have a bad habit of breaking or being shaken off. they’ve even tried taking a closer look at the calcifications in sharks’ cartilage skeletons, in hopes that “vertebral rings” could be used as age markers (stevens, 2009). these rings or “grown bands” have been used to estimate the age of younger sharks, but once a shark hits s****l maturity, the bands don’t hold as much validity due to the lack of definition in the bands, the consistency at which they form, and certain ring differences between species (stevens, 2009). unfortunately, with different results coming from radiocarbon dating (accounting for the number of carbon-14 isotopes present in a sample of shark) it is clear that the methods listed above are not always accurate (campana et al. 2011). as time goes on, the hope is that we find a fool proof way of accurately determining any given shark’s age, because knowing this simple piece of information can open the door to many new scientific breakthroughs in the research and conservation of these creatures.
post by @clairestrand
photo by @oceanramsey of #sharkidscarboard, one of the oldest females of the guadalupe white shark population.
Well i believe this is all in the bible . the fish and all living things in it will die and wash up on to the shore . the water and air will be poisoned .
but honestly besides that i feel like we need to do better as americans and be good to our oceans and our wildlife . this is why i have a career as a zoologist and a wild life preserver because all of this breaks my heart . if we could just change our ways for the better that would be great.
seeing my favorite animal which is the manatee dying and floating is just so sad .
there was a time when one of my tribes only lived off eating things out of the ocean . we are lucky that we as americans have other food sources .
Epic photo by talented underwater photographer of a curious sandbar shark! with the summer season in full swing we are missing these guys as our dives become increasingly dominated by galapagos sharks, although we have still been seeing some sandbars on our dives. we are lucky to have a stable population of this species here in hawaii, whereas their populations have declined between 84% and 97% over time periods of 13-41 years in the northwest atlantic as a result of rapid expansion of recreational and commercial fisheries in the last 20 years (iucn 2009). come out with our professionally trained team of marine biologists to learn more and meet these guys for yourself!
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although it’s one of the biggest coastal sharks in the world, sandbar sharks in new england are often shy and hard to approach. off the hawaiian islands of oahu, hawaii, and niihau, these sharks seem much bolder.
want to learn more about sharks or adoption visit our website: oneoceandiving.com & join us in the water in #hawaii on #oahu’s #northshore to #swimwithsharks and #divewithsharksinhawaii with a trained #marinebiologist / #sharksafetydiver check out our #shark and #marineresearch and our outreach program #learnaboutsharks and our non-profit conservation group and founders: and
want to join the team? become a ambassador looking to support in other ways? check out our not-for-profit marine conservation awareness apparel and gifts or at oneoceandesigns.com
mahalo and thank you for supporting #internationalsharkproject#hawaiisharkcount#sharkresearch#ocean#oneocean#savetheocean#savesharks#helpsavesharks#oceanconservation#sharkconservation .
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"the unicorn of the sea", or more commonly known as the narwhal (monodon monoceros), is a medium sized toothed whale that can be found in arctic coastal waters and rivers. they are known for their beautiful tusks, but what purpose do these tusks serve? the characteristic tusk is found mostly on males, and is actually a tooth! this ivory tusk tooth grows through the narwhal's upper lip, and grows in a spiral pattern. in rare occasions, there have been narwhals recorded that have two tusks, while others have none (drury, c., 2017). scientists are still studying the beneficial use of the narwhal's tusk(s), some believe it serves as a form of communication, while others believe that it is prominent in mating rituals. the scientists that believe it is used for communication, support this idea due to observing males rubbing their tusks together. previously, this behavior has been thought to be a display of aggressive male-to-male rivalry, but has been ruled out by many (national geographic, 2016). the tusk contains millions of nerve endings, which can help connect the outside environment directly to their brain. there was recently footage captured that showed a pod of narwhals surface feeding, where they used their tusks to stun small cod, which made them easier to catch. the tusks could serve more than one purpose, although there is not enough evidence to conclude its ultimate purpose. narwhals are threatened by human actions, as many humans capture them for their meat, or their tusks. although there is not enough data for a conclusion, they are considered to be near-threatened, and multiple sub-populations have evidence of decline. the european union has established an import ban on tusks, in hopes to revive their populations. other threats narwhals face are: oil/gas development and climate change (increased exposure to open water). increased development leads to more shipping vessels, which increase the opportunity for collisions and acoustic impacts (noise pollution) (wwf, 2017). photo by @brianskerry@natgeo
post by @skipp.bayless