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Apr 19: What the dinos did, and more...

Apr 19: What the dinos did, and more...

CBC19-04-2025
On this week's episode of Quirks & Quarks with Bob McDonald:
There's not a more vulnerable creature in nature than a baby bird. Tiny and immobile, they're easy pickings for predators. But the chicks of the white-necked jacobin hummingbird have evolved a unique defence. They disguise themselves as poisonous caterpillars to discourage those that might eat them. Jay Falk, an NSF postdoctoral fellow at the University of Colorado and Scott Taylor, director of the Mountain Research Station and associate professor at the University of Colorado, studied these birds in Panama. Their research was published in the journal Ecology.
Seals can dive at length to tremendous depth thanks to some remarkable adaptations, like the ability to collapse their lungs, and radically lower their heart rate. Chris McKnight, a senior research fellow at the University of St Andrews Sea Mammal Research Unit in Scotland, led a study looking to see if tweaking oxygen and C02 levels changed the seals' dive times. The researchers discovered that the seals have the unique ability to measure the oxygen levels in their tissues, so they can anticipate when they need to return to the surface before they get into trouble. The research was published in the journal Science.
As the joke goes, time flies like an arrow, fruit flies like a banana. Researchers recently demonstrated that fruit flies enjoy more than just aged produce. Using a custom carousel built to fly scale, scientists found that some, but not all, of their fruit flies would play on it, enjoying an activity that had nothing to do with the necessities of life. This brings up the possibility of variability in personality for fruit flies. Wolf Hütteroth is an associate professor at Northumbria University, Newcastle and was part of the team, whose research was published in the journal Current Biology.
Krill, the small, shrimp-like creatures that swarm the world's oceans and are particularly abundant in southern oceans, play a big role in marine food webs, connecting microscopic organisms with many of the oceans' larger animal species. Researchers in Australia investigated how krill respond to predator cues, like the smell of their feces. Nicole Hellessey, from the University of Tasmania, said the mere whiff of penguin feces affects the Antarctic krills' feeding behaviour and causes them to take frantic evasive action. The study is published in the journal Frontiers in Marine Science.
Dinosaur bones can tell amazing stories about these prehistoric beasts, but how do we piece together how they behaved? A new book dives into the many lines of evidence that can shed light on the behaviour of these extinct creatures. From fossils, to tracks they left behind, to their modern day descendents, paleontologist David Hone from Queen Mary University of London explores how scientists develop robust theories about how dinosaurs lived in his new book, Uncovering Dinosaur Behavior: What They Did and How We Know.
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Surging tourism is polluting Antarctica, scientists warn
Surging tourism is polluting Antarctica, scientists warn

Toronto Sun

time8 hours ago

  • Toronto Sun

Surging tourism is polluting Antarctica, scientists warn

The number of annual tourists visiting the white continent has risen from 20,000 to 120,000 over the last two decades The white continent is melting: Researchers are sounding the alarm about the threats to Antarctica. Photo by Jose Jorquera / University of Santiago USACH/AFP Soaring numbers of tourists and expanding research projects are increasingly polluting Antarctica, scientists warned Wednesday, a fresh blow for one of Earth's most pristine environments already threatened by human-driven climate change. This advertisement has not loaded yet, but your article continues below. THIS CONTENT IS RESERVED FOR SUBSCRIBERS ONLY Subscribe now to read the latest news in your city and across Canada. Unlimited online access to articles from across Canada with one account. Get exclusive access to the Toronto Sun ePaper, an electronic replica of the print edition that you can share, download and comment on. Enjoy insights and behind-the-scenes analysis from our award-winning journalists. Support local journalists and the next generation of journalists. Daily puzzles including the New York Times Crossword. SUBSCRIBE TO UNLOCK MORE ARTICLES Subscribe now to read the latest news in your city and across Canada. Unlimited online access to articles from across Canada with one account. Get exclusive access to the Toronto Sun ePaper, an electronic replica of the print edition that you can share, download and comment on. Enjoy insights and behind-the-scenes analysis from our award-winning journalists. Support local journalists and the next generation of journalists. Daily puzzles including the New York Times Crossword. REGISTER / SIGN IN TO UNLOCK MORE ARTICLES Create an account or sign in to continue with your reading experience. Access articles from across Canada with one account. Share your thoughts and join the conversation in the comments. Enjoy additional articles per month. Get email updates from your favourite authors. THIS ARTICLE IS FREE TO READ REGISTER TO UNLOCK. Create an account or sign in to continue with your reading experience. Access articles from across Canada with one account Share your thoughts and join the conversation in the comments Enjoy additional articles per month Get email updates from your favourite authors Don't have an account? Create Account In Antarctic areas where humans have been active, the concentration of fine particles containing heavy metals is 10 times higher than it was 40 years ago, the international team of researchers said in a new study. That change has come as the number of annual tourists visiting the white continent has risen from 20,000 to 120,000 over the last two decades, according to the International Association of Antarctica Tour Operators. 'The increasing human presence in Antarctica raises concerns about pollutants from fossil fuel combustion, including those from ships, aircraft, vehicles and supporting infrastructure,' the study in the journal Nature Sustainability said. Scientists work to measure the contamination of heavy metals in the pristine snow and iceJose Jorquera/University of Santiago USACH/AFP Photo by Jose Jorquera / University of Santiago USACH/AFP Ships carrying tourists are powered by dirty fossil fuels, which are the source of fine particles containing things like nickel, copper, zinc and lead. This advertisement has not loaded yet, but your article continues below. 'Snow melts faster in Antarctica due to the presence of polluting particles in areas frequented by tourists,' study co-author Raul Cordero told AFP. 'A single tourist can contribute to accelerating the melting of around 100 tons of snow,' said the scientist at the University of Groningen in the Netherlands. The researchers — from countries including Chile and Germany — spent four years traveling 1,200 miles (2,000 kilometers) in Antarctica to measure the contamination. The presence of heavy metals has also increased due to scientific expeditions. Research projects that stay for an extended time can have up to 10 times more of an impact than a single tourist, Cordero said. Antartica and the animals that live there are increasingly under threat by climate change and other human activitiesJose Jorquera/University of Santiago USACH/AFP Photo by Jose Jorquera / University of Santiago USACH/AFP The study acknowledged there have been 'meaningful steps forward' in attempts to protect Antarctica, such as a ban on highly polluting heavy fuel oil and the tourism industry embracing electric-hybrid ships. 'Nevertheless, our results show that more remains to be done to reduce the burdens of human activities in Antarctica,' including speeding up the transition to renewable energy and slashing fossil fuel use, the study said. A different Nature study also published on Wednesday warned that potentially irreversible changes in Antarctica driven by climate change could lift global oceans by meters and lead to 'catastrophic consequences for generations.' Sunshine Girls Columnists Sunshine Girls Toronto & GTA Toronto Maple Leafs

Antarctic Whales: Insights from Decades of Research
Antarctic Whales: Insights from Decades of Research

Japan Forward

time14-08-2025

  • Japan Forward

Antarctic Whales: Insights from Decades of Research

[SPONSORED] Japan's long-term surveys of whales in the Antarctic Ocean have deepened understanding of the region's whale populations. What scientists learned. Humpback whales have seen a remarkable recovery in their populations in both the southern and northern hemispheres. (©Institute for Cetacean Research) このページを 日本語 で読む Since 1987, Japan's Institute of Cetacean Research (ICR) has carried out long-term whale surveys in the Antarctic Ocean. Over the years, these efforts have deepened our understanding of whales and whale populations and the surrounding marine environment. This article offers a reader-friendly look at what the research has revealed so far. Minke whales were once believed to be a single species found across the world's oceans. However, research from Japan's whale sampling program revealed that those in the Southern Hemisphere are genetically distinct. They are now classified as Antarctic minke whales. These whales are widely distributed across the Southern Hemisphere. In summer, they migrate south to the Antarctic Ocean, where they feed on vast amounts of Antarctic krill to store energy for the year ahead. They exist in multiple populations, each with its own breeding grounds. Japanese research identified two major populations between the Indian Ocean and western Pacific (35°E to 145°W), which intermingle in the central part of this range. Historically, Antarctic minke whales reached sexual maturity at around 14 to 15 years of age. But after commercial whaling sharply reduced blue and other large baleen whales, krill became more abundant. This abundance allowed minke whales to mature earlier — now at just seven to eight years. That shift likely contributed to a population increase from around 100,000 to 515,000 individuals. Estimated Population of Antarctic Minke Whales in Area IV. (©Suisan Keizai Daily News) Southern right whales can grow up to 18 meters long, while newborns measure between 4.5 and 6 meters. They are easy to recognize by their enormous heads — roughly a quarter of their body length — and the callosities (roughened patches) on their skin. Unlike many other whale species, they have no dorsal fin or throat grooves. Pregnancy lasts about 12 months, and females give birth roughly every three years. Calving takes place in mid- to low-latitude coastal waters, including areas off southwestern Australia, New Zealand, South Africa, and both coasts of South America. After calving, the whales migrate to higher latitudes to feed. Due to their slow swimming speed and tendency to float after death, southern right whales were among the first to be targeted by whalers. Intense hunting by European and American fleets from the 17th to 19th centuries led to a steep decline in their numbers. By 1920, their global population had fallen to an estimated 300 individuals — already considered rare when modern whaling began. The species has been protected from hunting since 1937 and has now been under international protection for 86 years (as of 2023). Their original population is estimated at 55,000 to 70,000. In the Antarctic, they are mainly found in Area IV, where a 2007–08 survey estimated the population at 1,557 individuals, with an annual growth rate of 5.9%. Estimated Population of Southern Right Whales in Area IV. (©Suisan Keizai Daily News) Fin whales are most commonly found between 40°S and 60°S, a region known for its strong westerly winds and rough seas. Some whales venture even farther south beyond 60°S, which contributes to year-to-year fluctuations in population estimates. Commercial hunting of fin whales in the Southern Hemisphere was banned in 1976. As of 2023 — 47 years later — there are encouraging signs of recovery. In the Southern Ocean south of 60°S, the Indian Ocean group (Areas III East and IV) was estimated at 3,087 individuals in 1995/96, but declined to 2,610 in 2007/08. In contrast, the South Pacific group (Areas V and western VI) grew dramatically from 1,879 to 14,981 individuals over the same period. These groups are now showing annual growth rates of 8.9% and 12%, respectively. Estimated Population of Fin Whales in the Indo-Pacific Region South of 60°S. (©Suisan Keizai Daily News) In the Southern Hemisphere, adult humpback whales can reach about 16 meters for females and 15 meters for males. Newborns typically measure between 4.5 and 5.0 meters. Their most distinctive feature is their exceptionally long pectoral fins, which can stretch to one-third of their body lasts around 12 months. Calving takes place in warmer, low-latitude coastal waters, after which mothers and calves migrate to cooler, high-latitude feeding grounds south of 50°S. From 1904 to 1963, humpbacks were heavily targeted by commercial whaling, and their numbers declined steeply. Hunting was banned in the Southern Hemisphere in the 1963/64 season and later extended worldwide in 1966. When Japan's Antarctic Research Program for Whales (JARPA) began, humpback sightings were so rare that spotting just one became a highlight of cruise logs. But beginning in the late 1990s, researchers started to witness a remarkable recovery. In the Indian Ocean sector of Antarctica (Area IV), humpbacks eventually became the dominant species by biomass south of 60°S during summer, overtaking Antarctic minke whales. Since the mid-1990s, the IWC Scientific Committee has raised questions about the reliability of JARPA's findings, prompting Japan to defend the credibility of its research. In August 2008, the International Union for Conservation of Nature (IUCN) released an update: although some regional concerns remain, the global humpback whale population — including those in the Northern Hemisphere — had surpassed 60,000 and was continuing to grow. The IUCN reclassified the species from "Vulnerable (VU)" to "Least Concern (LC)" on its Red List. Recent estimates put the population at 29,067 in Area IV and 13,894 in Area V, with both regions showing steady growth. Surveys conducted by Australia and New Zealand have also confirmed this upward trend. Estimated Population of Humpback Whales in Area IV. (©Suisan Keizai Daily News) Visual surveys conducted in the Antarctic during the 1980s estimated the blue whale population at just 700 individuals, highlighting the species' critically endangered status at the time. By the 2005/06 to 2007/08 surveys, the estimated number of blue whales south of 60°S in the Southern Ocean had increased to 1,223. The population is now believed to be growing at an annual rate of about 8.2%. Even so, the numbers remain very low — just around 2% of the species' estimated original population of 250,000. Still, more than 60 years have passed since hunting was banned in the 1963/64 season, and there are now gentle signs that the species is on a slow path to recovery. Estimated Population of Blue Whales in the Indo-Pacific Region South of 60°S. (©Suisan Keizai Daily News) This program was launched in response to the International Whaling Commission (IWC)'s 1982 decision to place a moratorium on commercial whaling. The IWC's main focus was the Antarctic minke whale. Surveys focused on population size, natural mortality, recruitment rates, and the ecological role of whales in the Antarctic Ocean. Researchers also examined how environmental changes were affecting whale populations and studied the distribution of different whale groups across the region. JARPA II expanded the scope of research to include not only Antarctic minke whales but also fin whales and humpback whales. The program aimed to explore how different whale species interact with one another, monitor the broader Antarctic ecosystem, and develop models of ecological competition among whales. In 2014, the International Court of Justice (ICJ) reviewed the program following a case brought by Australia. While the court acknowledged the scientific value of the research, it ruled that JARPA II did not fall within the scope of Article VIII, Paragraph 1 of the International Convention for the Regulation of Whaling. One of the reasons cited was the program's failure to meet its target sample size. As a result, JARPA II came to an end later that year. NEWREP-A was developed in response to the ICJ ruling. The program was launched after expert review by the IWC and discussions within its Scientific Committee. Its main goal was to improve the accuracy of biological and ecological data used to calculate catch limits for Antarctic minke whales under the Revised Management Procedure (RMP). It also aimed to deepen understanding of the Antarctic ecosystem through the development of ecosystem models. This ongoing program continues Japan's long-term efforts to study whales in the Antarctic with a focus on sustainable use of marine resources. All research is conducted through non-lethal methods. The survey looks at population size and trends among large whale species, as well as their distribution, migration patterns, and stock structure. Since the launch of JASS-A, no whales have been caught, and researchers are now working to update population estimates based on data from the 2010s and 2020s. Surveys are primarily being conducted in Areas IV and V. (©Suisan Keizai Daily News ) (Provided by the Institute of Cetacean Research) (The report is published in cooperation with the Institute of Cetacean Research in Japan. A version of it was first published in Japanese in the Suisan Keizai Daily News on February 28, 2023. Let us hear your thoughts in our comments section.) Author: Suisan Keizai Daily News このページを 日本語 で読む

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