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Current press releases

Sturgeon at fish market in Eastern Europe (photo: George Caracas/WWF)
Sturgeon at fish market in Eastern Europe (photo: George Caracas/WWF)

Wild caviar, a pricey delicacy made from sturgeon eggs, has been illegal for decades since poaching brought the fish to the brink of extinction. Today, legal, internationally tradeable caviar can only come from farmed sturgeon, and there are strict regulations in place to help protect the species. However, by conducting genetic and isotope analyses on caviar samples from Bulgaria, Romania, Serbia, and Ukraine—nations bordering the remaining wild sturgeon populations—a team of sturgeon experts found evidence that these regulations are actively being broken. Their results, published today in the journal “Current Biology”, show that half of the commercial caviar products they sampled are illegal, and some don’t even contain any trace of sturgeon.

Grey wolf (Canis lupus) in its preferred habitat (photo: Jan Zwilling/Leibniz-IZW)
Grey wolf (Canis lupus) in its preferred habitat (photo: Jan Zwilling/Leibniz-IZW)

The return of the grey wolf (Canis lupus) to Germany, which began 23 years ago in the region of Lusatia in Eastern Germany, is a process of great ecological and social significance. Therefore, a precise understanding of the recolonisation of the original habitat by the grey wolf and a reliable prediction of its future potential distribution are highly valuable. A detailed comparison of different approaches to spatial modelling using 20 years of distribution data now unravelled the complexity of the recolonisation process. A team led by scientists from the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) shows in a paper in the scientific journal “Diversity and Distributions” that grey wolf habitat selection changed from the early (when they cherry-pick the finest locations) to late phases of recolonisation (when they are much less selective) in a particular area. These results are a refinement of the team’s earlier habitat modelling from 2020, originally published by the Federal Agency for Nature Conservation.

10th oocyte collection in northern white rhino Fatu, conducted by the BioRescue Team in July 2022
10th oocyte collection in northern white rhino Fatu, conducted by the BioRescue Team in July 2022

The BioRescue project develops and pioneers advanced assisted reproduction technologies (aART) for conservation in the face of the imminent extinction of most rhino species and subspecies. In a new scientific analysis published in the journal “Reproduction”, the team evaluated 65 aART procedures comprising hormonal ovarian stimulation, ovum pick-up (OPU), in-vitro oocyte maturation and in-vitro fertilisation (IVF), embryo culture and cryopreservation conducted from 2015 to 2022. The evaluation showed that aART is safe for the donor females with no detrimental health effects, and successful in that it yielded 51 embryos. In fact, regular OPUs benefited the reproductive health of individual female rhinos by improving ovarian function, increasing follicle numbers and instigating the regression of pathological structures such as ovarian cysts.

Mosquitoes collected, identified, and tested for viruses by the scientific team (photo: Georg Eibner, Charité)
Mosquitoes collected, identified, and tested for viruses by the scientific team (photo: Georg Eibner, Charité)

How are environmental changes, loss of biodiversity, and the spread of pathogens connected? The answer is a puzzle. Scientists from Charité – Universitätsmedizin Berlin in cooperation with the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) have now described one piece of that puzzle in the journal “eLife”, showing that the destruction of tropical rainforests harms the diversity of mosquito species. At the same time, more resilient species of mosquitoes become more prevalent – which also means the viruses they carry are more abundant. If there are many individuals of a given species, those viruses can spread quickly.

A team from Colossal at a BioRescue procedure at the Ol Pejeta Conservancy in Kenya (photo: Steven Seet)
A team from Colossal at a BioRescue procedure at the Ol Pejeta Conservancy in Kenya (photo: Steven Seet)

With only two living females left, the partnership will contribute to the genetic recovery of the northern white rhino from complete extinction. Colossal developed a pioneering toolkit for the challenging task to restore genetic diversity from museal specimens for a living population of critically endangered species.  

Common noctules trapped in urban window in the Ukrain war zone (photo: A. But)
Common noctules trapped in urban window in the Ukrain war zone (photo: A. But)

Russia’s war in the Ukraine has severe consequences not only for humans, it also has detrimental effects on populations of urban and semi-urban wildlife in the attacked cities and regions. Scientists from the Ukrainian Bat Rehabilitation Center recently examined the effects of war-related damages to buildings on urban populations of one important and widespread bat species, the Common Noctule (Nyctalus noctula), in the city of Kharkiv in north-eastern Ukraine. They showed that many buildings used by bats as roosts have been destroyed and approximately 7,000 bats were killed. In addition, partially destroyed buildings have become a death trap for bats, resulting in several thousand more victims. The findings are published in the “Journal of Applied Animal Ethics Research”.

 

 

BioRescue oocyte collection in Kenya (photo: Jon A. Juarez)
BioRescue oocyte collection in Kenya (photo: Jon A. Juarez)

Four years since the start of this ambitious project to save the Northern White Rhino from extinction, the BioRescue consortium has made significant progress towards its ultimate aim. Using advanced assisted reproduction technologies, 29 northern white rhino embryos have been created and cryopreserved, ready for a future transfer to a surrogate mother. Most recently, in May 2023, 18 eggs were collected from female Fatu. This resulted in five new embryos created, the highest number of embryos from any collection to date. The sperm for fertilisation came from two different bulls, thereby improving genetic diversity. The BioRescue research project is mainly funded by the German Federal Ministry of Education and Research (BMBF).

Domestic boar (Photo: Nicolas Castez - unsplash.com)
Domestic boar (Photo: Nicolas Castez - unsplash.com)

The protein AQN-3 from boar sperm binds negatively charged phospholipids

Mammalian seminal fluid contains a variety of proteins secreted by the accessory sex glands that are important for the processes involved in fertilisation. One of these proteins, which is found in ungulates - and in particularly large quantities in boars - is the spermadhesin AQN-3. A science team from the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), the Humboldt University of Berlin (HUB) and the Leibniz Institute for Molecular Pharmacology has studied the protein and discovered unexpected properties that could help sperm remain functional until they reach the egg. The findings are published in the scientific journal “Chemistry and Physics of Lipids”.