Lemon Shark in black and white

Sharks

angular roughshark
Angular roughshark (Gervais et Boulart / Public domain via Wikimedia Commons)

The Angular Roughshark: A Unique Deep-Sea Predator

A Distinctive Look

The Angular roughshark (Oxynotus centrina) stands out with its unique, angular body shape that is unlike any other shark. Its body has a distinctive humped, almost pyramid-like appearance due to its high, triangular dorsal fins and compressed, thickset torso. The first dorsal fin, located just behind the head, is particularly tall and prominent, while the second is slightly smaller. These large fins give the shark its sharp-edged, almost boxy profile, which contrasts with the streamlined bodies of most other sharks.

Environmental Stress Drives Sharks from Coral Reefs

The study, led by Michael J. Williamson, analysed data from over 700,000 shark detections across the Chagos Archipelago in the Indian Ocean between 2013 and 2020. It reveals that grey reef sharks are showing signs of distress. As coral ecosystems are impacted more and more by pollution and climate change, these sharks are reducing their time on the reefs. Instead, they are expanding their ranges and spending more time away from their ranges.

A great white shark
The great white shark

Great White Sharks Separated Into Three Population Groups

The study, led by researcher Isabel Wagner, used a groundbreaking approach. They combined advanced genetic techniques (including target gene capture sequencing and whole-genome re-sequencing), to analyse the DNA of white sharks from across their global range. Eighty-nine individual sharks were examined through target gene capture sequencing, and 17 sharks were studied through whole-genome re-sequencing. 

Tiger shark off the Bahamas. Sharks occupy a wide variety of niches and are essential to ecosystem functioning.

Ecological Importance of Big Sharks

A new study has shed light on the surprising ways that the great sharks contribute to their ecosystems. They help transport nutrients across marine ecosystems, which involve a variety of marine life forms. As the climate warms and human activities continue to alter ocean conditions, their roles are shifting. Some species are expanding their ranges into cooler waters, affecting new areas and interactions.

Broadnose sevengill sharks can be found in temperate kelp forests around the world, except in the North Atlantic.

New Shark Species Showing up in Puget Sound

During ten days of fieldwork in 2022 and 2023, the researchers caught ten sharks from the broadnose sevengill and the endangered soupfin species.

The Salish Sea separates northwest Washington from British Columbia's Vancouver Island. The 6,500-square-mile body of water stretches into Washington as Puget Sound, and the sharks were caught close to Olympia near the sound's southernmost point.