Whale sharks, reefs and a tragic fate

Marine biologist Jorge Fontes took the winning photo in the “BMC Ecology and Evolution 2024” photo competition. Fontes works at the Okeanos-UAc, Institute of Marine Sciences. He studies the effects of fishing on the largest animals in the oceans. He photographed the largest fish in the world: the whale shark. It lives in tropical and subtropical waters and eats plankton, which it filters through its mouth. In summer, whale sharks congregate near the Azores. As these waters are not very productive then, there is hardly any plankton. Instead, the whale sharks feed on snipefish, which are herded together at the surface by schools of tuna. When the fish are gathered, the whale sharks use a strong undertow to fill their huge mouths with food. The feeding partnership between sharks and tuna is rare. To better understand the behavior and effects of tuna fishing, Jorge Fontes' team has equipped whale sharks with accelerometers, cameras and sensors to measure position, pressure and temperature.

Victor Huertas, a postdoctoral researcher at the College of Science and Engineering at James Cook University in Australia, took the winning picture in the “Protecting our planet” category.

Victor Huertas, a postdoctoral researcher at the College of Science and Engineering at James Cook University in Australia, took the winning picture in the “Protecting our planet” category. The photo shows a ranger assessing the condition of corals on Lady Musgrave Reef in the southern Great Barrier Reef. Corals bleach when they are stressed. In doing so, they expel the colorful, photosynthetic algae that live inside them and supply them with nutrients. The Great Barrier Reef Marine Park Authority now reports that the UNESCO World Heritage-listed reef system was hit by a coral bleaching event last summer - the fifth mass bleaching event in the Great Barrier Reef since 2016. Victor explains: “Equipped with a slate and data sheets, the ranger examines the coral colonies and documents their condition. Monitoring coral health is important to understand and preserve this fragile ecosystem.

Roberto García-Roa, evolutionary biologist and conservation photographer at Lund University in Sweden, won the “Protecting our planet” category with his photo.

Roberto García-Roa, evolutionary biologist and conservation photographer at Lund University in Sweden, won the “Protecting our planet” category with his photo. His picture tells the story of “Bruma”, a Bonelli's eagle that died of an electric shock caused by a high-voltage power line. Bonelli's eagles are considered endangered in the European Union. GPS transponders track the movements of the eagles and help to identify areas with high mortality rates near power lines. In the picture, Bruma, which has been tagged with a GPS transmitter, lies lifeless. The information collected by the transmitter made it possible to identify the power lines that Bruma had visited before her death. The information is crucial to prevent other animals from suffering the same fate. Such measures are important as thousands of birds die from electrocution in Europe every year.

Anusuya Chinsamy-Turan, paleontologist at the University of Cape Town, submitted the second place for “Life close-up”.

Anusuya Chinsamy-Turan, paleontologist at the University of Cape Town, submitted the second place for “Life close-up”. She demonstrates how fossilized bones provide valuable information about extinct species. “Fortunately, the microscopic structure of fossilized bones is still intact even after millions of years,” explains Chinsamy-Turan. Viewed under a microscope, this image of a thigh bone of Megapnosaurus, a predatory dinosaur from southern Africa, reveals information about the biology of this approximately 190 million-year-old animal. The large black areas contained blood vessels, nerves and other connective tissue, while the smaller black patches are the spaces where bone cells were located. After death, the organic tissue decomposes. The empty spaces are filled with sediments and minerals. The bright colors provide information about the structure of apatite, the mineral component of bone. Examining the microstructure of fossilized bones provides valuable insights into the life history of extinct vertebrates. This includes details about sex, growth rate, the presence of diseases and the effects of environmental influences.