Press releases

Reproducing efficiently in captivity is crucial for the survival of many wildlife species, yet reproductive success is often lower than in the wild. Currently, many zoo population management strategies prioritise the genetic diversity of captive populations. Scientists now argue that a broader perspective is required which also includes behaviour, life-history, husbandry and environmental considerations. This would improve breeding success in zoos and the maintenance of the diversity of traits, behaviours, and phenotypes of threatened species. In a paper published recently in the scientific “Journal of Zoo and Aquarium Research” they compare different population management approaches and conclude that prioritizing genetic factors to the exclusion of all others may have detrimental effects: For example, in small groups of unrelated adults, conflicts are likely to be more frequent than in larger groups with relatives present who had the chance to develop differentiated socialisation and learning repertoires.

Germany potentially provides many suitable areas for grey wolf territories. This means that wolves may potentially settle down in large parts of the country where they were extinct until around the year 2000. It should be expected that they will disperse through other areas not delineated as suitable as well. These are the results of a study conducted by the Federal Documentation and Consultation Centre on Wolves (DBBW), the Leibniz Institute for Zoo and Wildlife Research (IZW), the Technical University of Berlin, the Humboldt-Universität zu Berlin and the Research Institute for Wildlife Ecology (Vienna). The study was commissioned and published by the Federal Agency for Nature Conservation, Germany.

Another piece of the puzzle about the longevity of the corpus luteum in lynxes has been uncovered. Scientists at the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) and the Leibniz Institute for Molecular Pharmacology (Leibniz-FMP) discovered that selected anti-oxidative enzymes, especially the enzyme superoxide dismutase (SOD2), may play an important role to maintain the unusual longevity of the corpus luteum in lynxes. It is highly likely that SOD2 not only detoxifies the reactive oxygen radicals in the cells, but also inhibits programmed cell death. The results were recently published in the scientific journal Scientific Reports of the Nature Group.

A research team at the German Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) developed a method to isolate and cryopreserve testicular cells. This will allow the safekeeping and biobanking of gametes and other cells of the male reproductive tract of threatened or endangered feline species. The findings have been published in the scientific journal "Cryobiology".

Common noctules – one of the largest bat species native to Germany – are searching for their fellows during their hunt for insects above farmland. Scientists from the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) show in a paper published in the journal “Oikos” that bats forage on their own in insect-rich forests, but hunt collectively in groups over insect-poor farmland. They seem to zoom in on places where conspecifics emit echolocations during the capture of insects, an inadvertent clue that reveals high-yielding areas to others. However, “listening” to their hunting companions to find food only works when sufficient numbers of bats forage in the same area. If numbers continue to decline, density could fall below a critical level and joint hunting could become difficult or impossible. This could pose an additional threat to the survival of species such as the Common noctule.

Similar to humans, wild animals’ reaction to disturbance is accompanied by releasing hormones, such as cortisol. To understand the impact of various “stress” factors – for example competition for food, encounters with predators, or changing environmental conditions – on wildlife, scientists first need to determine the baseline levels of relevant hormones for each species. Researchers from the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) now uncovered possible pitfalls of the commonly used hormone analysis method that overestimate concentrations of cortisol and thus lead to overstated conclusions. They investigated whether glucocortiocoid hormones deposited in animal hair can be reliable biomarkers to indicate the impact of disturbances. The source of errors in the commonly used antibody-based enzyme immunoassays (EIA) method is described in a recently published article in the scientific journal “Conservation Physiology”.

Ageing is an inevitable part of life, yet some species are ageing very differently than others, even than very similar ones. Naked mole rats for example, an east African rodent of a size comparable to moles or mice, show a strongly delayed process of ageing and live up to 30 years. Scientists from Russia, Germany and Switzerland now confirmed a mechanism in mouse, bat and naked mole rat cells – a “mild depolarization” of the inner mitochondrial membrane – that is linked to ageing: Mild depolarization regulates the creation of mitochondrial reactive oxygen species (mROS) in cells and is therefore a mechanism of the anti-ageing program. In mice, this mechanism falls apart at the age of 1 year, while in naked mole rats this does not occur until ages of up to 20 years. This newly confirmed mechanism is described in detail in a paper published in the “Proceedings of the National Academy of Sciences of the USA”.

For wildlife, cities can present new opportunities as well as threats. Researchers from the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) and the Luxembourg National Museum of Natural History (NMNH) analysed genetic material of red foxes (Vulpes vulpes) inhabiting Berlin and its surroundings. They identified two genetically distinct, adjacent “urban” and “rural” fox populations and revealed that physical barriers such as rivers or man-made structures reduce the exchange between these populations but also differences in human activity in these landscapes play a major role. The researchers suggest that avoidance of sites of human activity may drive foxes into costly trade-offs as they prefer to disperse along potentially dangerous transportation infrastructures. The study was recently published in the scientific journal “Molecular Ecology”.

Widespread poaching in tropical biodiversity hotspots is causing unprecedented declines in wildlife populations, known as defaunation. A new study published in the journal “Diversity & Distributions”, provides evidence that large-scale systematic surveys and novel methods of data collection and analysis, are necessary to assess the extent and distribution of poaching and its impact on biodiversity in forest exposed to severe defaunation. Mapping biodiversity in this way will provide information critical to protecting rare species that may still exist in these landscapes. The research was conducted in the Annamite mountains on the border of Laos and Vietnam, an area with an exceptionally high occurrence of endemic species that is threatened by illegal poaching through the setting of wire snares. The research team, led by the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), comprised scientists, conservationists and government counterparts, including representatives from WWF-Vietnam and WWF-Laos.

Nairobi, Kenya - In August 2019 a team of scientists and conservationists broke new ground in saving the northern white rhinoceros from extinction. They harvested eggs from the two remaining females, artificially inseminated those using frozen sperm from deceased males and created two viable northern white rhino embryos. With great support from the Kenyan Government and in the presence of Hon Najib Balala, – Kenya’s Cabinet Secretary, Ministry of Tourism and Wildlife – the team repeated the procedure on December 17, 2019, and was able to create a new embryo over Christmas. This significantly increases the chances of successfully producing offspring. The procedure has proven to be safe and reproducible, and can be performed on a regular basis before the animals become too old. Preparations for the next steps of the northern white rhino rescue mission are underway.