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.
Shark fishing was completely banned in the Maldives in 2010 so when the country announced plans to discuss legalising the practice again, it created a massive backlash from the international community.
Sharks have always been a valuable tourist attraction in the small island nation and the declining status of shark fisheries, exacerbated by unresolved conflicts with other stakeholders led to the declaration of total shark fishing ban in 2010. With the shark fishing ban in place, sharks are now caught as bycatch in the Maldivian fisheries.
Researchers conclude the northward range shift demonstrates water temperatures within their preferred temperature range of juvenile white sharks are becoming harder to find.
The animals have historically remained in warmer waters in the southern California Current; Between 1982 and 2013, the northernmost edge of the juveniles' range was located near Santa Barbara (34° N).
Sleep is ubiquitous across the animal kingdom but despite anecdotal reports of sleep-like behaviour in nurse sharks and other seafloor-dwelling species, the question of whether sharks actually sleep has been intensely debated but remains unknown. A key criterion for separating sleep from other quiescent states is an increased arousal threshold. True sleep is characterised by a lack of movement that can be rapidly reversed and a decreased awareness of surroundings.
The Lost Shark, Carcharhinus obsoletus, is already extinct, and others that are expected to follow soon include four species each of hammerhead and angel sharks, from the world’s most threatened shark families. In spite of all the press that shark conservation has received in the past two decades, no effective protection of sharks has been established, no sharks have been saved, and their decline into extinction is ever more apparent.
Knowledge of the habitat use and migration patterns of large sharks is important for assessing the effectiveness of large predator Marine Protected Areas (MPAs), vulnerability to fisheries and environmental influences, and management of shark-human interactions.
Researchers from James Cook University's ARC Center of Excellence for Coral Reef Studies examined stomach contents of reef sharks and conducted chemical analyses of shark body tissue to find out what they had been eating.
Somewhat surprisingly after pumping sharks' stomachs to identify the contents of the last meal, the most common thing to find was in fact, nothing. "These results suggest that reef sharks eat small meals infrequently and opportunistically," Lead author, Dr Ashley Frisch said.
The paper presents the reasons why large predators of great ecological importance cannot supply the rising demand for shark fins, which is driven by profits that rival the drug trade and involves the fisheries of nations around the globe. They have essentially run out of fish so are targeting sharks now that the shark fin trade has made them valuable.
Development of a vaccine against Covid-19 could come at the expense of sharks, researchers warn; A key ingredient used in vaccines to enhance immune response and increase effectiveness, squalene — an oily substance found in plants and even human skin — is particularly concentrated in shark livers.
Many divers dream of the day they find themselves swimming beside a whale shark. Its gentle demeanour and huge size presents a unique humbling experience that is second to none.
Yet, there is much we still do not know about whale sharks.
Today, one of their hidden mysteries have been unlocked–their age.
Until recently, it was hard to fix a number to their age, as they do not have bony structures (otoliths) which are traditionally used to calculate the age of fish.
What we see is that sharks are being targeted by international factory fleets around the world who trail millions upon millions of baited hooks through their realm, trawl the sea floors for rays, skates and other bottom dwellers to 4,000 metres, and slaughter them by the millions. Sharks are the only profitable prey remaining, now that ninety percent of the original (fish) fisheries are fished out.
