So I asked leading shark ethologist and behaviourist, Professor Samuel 'doc' Gruber to elaborate. After pointing out how much pain women feel when they give birth, making the point that suffering has no effect on reproduction, he reminded me that sharks evolved their mating behaviours and the physical structures involved, separately from other animals.
Scientists with the New England Aquarium found that nurse sharks, Ginglymostoma cirratum, returned to the waters off the Dry Tortugas, 70 miles (113km) from Key West, to mate for up to 28 years. The Dry Tortugas has been known as a courtship and mating site for nurse sharks since 1895.
A 30-year (1992–2021) study documented long-term site fidelity to this area, with data from 137 adult sharks.
It certainly looks “prehistoric”—whatever that means. Cigar-shaped, blunt-snouted, with that slightly “sock-puppet-looking” smirk, the overall look of this big beastie is very much that of an ancestral shark, like some of the deep-water dogfishes, the sleeper sharks and others. Indeed, fossil remains similar to modern sevengills and sixgills are known from the Jurassic and perhaps much earlier.
Researchers from the New South Wales (NSW) Department of Primary Industries (DPI) and Deakin University fitted an adult male shark with a pop-up satellite tag and tracked it for more than five months.
After being tagged, the shark swam more than 20km out to sea, then headed north to Queensland.
It roamed between 80 and 280km offshore between Agnes Water and the southern end of the Great Barrier Reef, before heading to the cooler waters in southern NSW, Victoria and Tasmania.
The Shark Fin Sales Elimination Act represents a multiyear effort by lawmakers, under pressure from animal-rights and ecological organizations such as the Animal Welfare Institute and Oceana, to ban the trade of shark fins.
Seventeen states and three U.S. territories have banned or restricted the intrastate sale of shark fins, but instituting a federal framework is critical as fins imported and sold in the U.S. can come from endangered or threatened shark species, or from sharks that were finned.
Marine scientists have invented a small device that can reduce shark bycatch numbers by emitting short electrical pulses as a deterrent.
When clipped on the fishing line next to a baited hook, the battery-operated SharkGuard works by emitting a short localised pulse every two seconds. This causes the shark’s ampullae of Lorenzini (electrical sensors around its nose and mouth) to be overstimulated, thus prompting it to swim away.
That feeding or attracting wildlife with food to enable better viewing opportunities by ecotourists (i.e. provisioning tourism) has the potential to alter the natural behaviour and physiology of animals has long been well established.
But how the physiological state of wildlife might be related to the nature and magnitude of these effects remains poorly understood.
The186-nation Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) has voted for the first time to regulate the trade that kills millions of sharks every year.
Imagine you are riding the waters on your trusty surfboard, savouring the rush of emotions and feeling totally alive, when you glance down into the waters and you spot a shark swimming by.
Does your heart skip a beat and you immediately look for the fastest way to get back to dry land?
Or do you continue what you are doing, feeling more at one with the elements?
Well, if you are like more than 50 percent of surfers, you would simply continue surfing, according to a survey of 391 surfers, conducted by the University of South Australia.
Scientists have observed instances in which tuna rub themselves against the side of sharks. Apparently, they do this to dislodge painful parasites that cling to their head, eyes and gills.
“Shark skin is really smooth in one direction and it’s like sandpaper in the other,” said Chris Thompson, a Research Fellow at the University of Western Australia.
Thompson and his colleagues observed this behaviour after studying the footage of floating, baited underwater cameras which they had deployed in 36 regions in the Pacific, Indian and Atlantic Oceans in 2012 to 2019.
In Ireland, new regulations giving the basking shark the "protected wild animal" status under the Wildlife Act came into effect on 9 October. The order was signed by Minister of State for Heritage Malcolm Noonan, and Minister for Agriculture, Food and the Marine Charlie McConalogue. This legislation was heavily supported by the Irish Basking Shark Group (ISBG), an international network of researchers, educators, and community representatives founded in 2009.
