Tag Archives: MARINE ECOSYSTEMS

Giraffes, parrots, oak trees, cacti among many species facing extinction

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It may be surprising to learn that even giraffes, parrots, and oak trees are included in the list of threatened species, as well as cacti and seaweed.

Seaweed is one of the planet’s great survivors, and relatives of some modern-day seaweed can be traced back some 1.6 billion years. Seaweed plays a vital role in marine ecosystems, providing habitats and food for marine lifeforms, while large varieties – such as kelp – act as underwater nurseries for fish.

However, mechanical dredging, rising sea temperatures and the building of coastal infrastructure are contributing to the decline of the species.

The world’s trees are threatened by various sources, including logging, deforestation for industry and agriculture, firewood for heating and cooking, and climate-related threats such as wildfires.

Unsplash/Shane Stagner.
Kelp, a type of seaweed, can be fed to animals and could help to reduce greenhouse gas emissions.

It has been estimated that 31 per cent of the world’s 430 types of oak are threatened with extinction, according to the International Union for Conservation of Nature (IUCN) Red List of threatened species. And 41 per cent are of “conservation concern”, mainly due to deforestation for agriculture and fuel for cooking.

Giraffes are targeted for their meat, and suffer from the degradation of their habitat due to unsustainable wood harvesting, and increased demand for agricultural land; it’s estimated there are only around 600 West African giraffes left in the wild.

Scientists take a deep dive into how ‘elasmobranchs’ use the ocean depth

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Using sophisticated electronic tags, scientists have assembled a large biologging dataset to garner comparative insights on how sharks, rays, and skates – also known as “elasmobranchs” – use the ocean depths. While some species spend their entire lives in shallow waters close to our shores on the continental shelf, others plunge hundreds of meters or more off the slope waters into the twilight zone, beyond where sunlight penetrates. This new understanding of how elasmobranchs use the ocean will enable policymakers and resource managers the opportunity to examine the threats these animals face, and guide future management and conservation plans.

A study published Aug. 19 in Science Advances, led by Stanford University and ZSL (Zoological Society of London) researchers, is the largest global investigation of where and when a diverse group of elasmobranchs move vertically. A team of 171 researchers from 135 institutions across 25 countries brought together two decades of data from satellite and archival tags that remotely tracked the movements and behaviors of 38 species in oceans across the globe.

“For the first time, we have a standardized, global database that we used to fill important knowledge gaps about the diving behaviors of sharks and rays,” said Samantha Andrzejaczek, co-lead author of the study and a postdoctoral research fellow at the Hopkins Marine Station of Stanford University. “This will enable better understanding of what fisheries interact with elasmobranchs and how to improve management of many of these long-lived animals.”