Lemon Shark in black and white

Sharks

Basking Shark
Basking Shark

Drones Reveal Basking Shark Mating Behaviour

The study describes how the researchers launched a drone from the beach and flew it to the site of a disturbance spotted from shore. Two basking sharks (Cetorhinus maximus) were immediately seen in close proximity—one near the bottom and one near the surface. The latter was confirmed to be a mature male due to the presence of claspers, while the shark near the bottom appeared to be a female.

Tiger shark teeth
A tiger reveals her teeth

Sharks: Loss of Diversity Through Time

Sharks first appeared in the fossil record about the same time that plants covered the land, nearly half a billion years ago. Evolution has made them so perfect that they have retained their main characteristics over all of this abyss of time. But despite their formidable lineage, modern sharks face unprecedented threats and challenges that endanger their diverse roles within ecosystems.

Cookiecutter shark preserved
Cookiecutter shark preserved

Cookiecutter Shark Bites: Moonless Nights are Risky

Steven Minaglia, a faculty member from the University of HawaiĘ»i with a passion for channel swimming has published a study that sheds light on the rare interactions between cookiecutter sharks (Isistius brasiliensis) and humans. Minaglia is an associate professor of obstetrics, gynaecology, and women’s health at the John A. Burns School of Medicine, and reveals how environmental factors can elevate the chances of being bitten. 

Nurse sharks mating
Nurse sharks preparing to mate (Harold 'Wes' Pratt / Granted by source)

Proven: Marine Protected Areas Boost Shark Populations

The study, spanning 66 marine reserves across 37 countries worldwide, sheds light on the stark contrast in shark abundance between fully protected zones and areas open to industrial fishing. Reef-dwelling species such as Caribbean reef, grey reef, whitetip reef, and nurse sharks exhibited nearly double the population density within fully protected marine reserves compared to fishing-permitted zones.

A great white shark
Great White Shark

A Closer Look at Human-Shark Encounters

A recent article by Sam Fletcher begins with the gripping account of a wildlife videographer, Scott Fairchild. Using a drone, he captures a heart-stopping moment when a great white shark repeatedly approaches a lone swimmer off the coast of San Diego. Yet suddenly the shark veers away and disappears. Fairchild states that he has seen countless such encounters between swimmers and white sharks off the Californian coast.

pregnant shark
A pregnant reef shark (Ila France Porcher)

pH Threshold Unlocks Reproductive Maturity in Sharks and Rays

For fish and other water-breathing animals like sharks and rays, reaching reproductive maturity is a crucial milestone that impacts their entire life history. The size at which they reach maturity, coupled with their subsequent growth rate, affects their longevity and reproductive capacity. Now, researchers have pinpointed a specific pH threshold, termed the "reproductive respiration threshold" (RRT), which kickstarts the hormonal processes leading to maturation.

Shark nets in New South Wales
Shark nets in New South Wales (Sam Hood, Public domain, via Wikimedia Commons)

Unintended Deaths Soar in NSW Shark Net Program

According to the findings, more than half of the 208 non-target species ensnared in the nets over the past eight months met a grim fate, with 134 animals, including critically endangered grey nurse sharks and leatherback turtles, among the casualties. The figures, made public as the nets were removed for the season, highlight the significant toll the program exacts on marine biodiversity.