Ursula Siebert

Ursula Siebert
University of Veterinary Medicine Hannover | TiHo · Institut für Terrestrische und Aquatische Wildtierforschung

Prof. Prof. h. c. Dr.

About

585
Publications
126,626
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11,222
Citations
Citations since 2017
269 Research Items
6673 Citations
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201720182019202020212022202302004006008001,0001,200
201720182019202020212022202302004006008001,0001,200

Publications

Publications (585)
Article
The Harbour porpoise (Phocoena phocoena) is a highly mobile cetacean species primarily occurring in coastal and shelf waters across the Northern hemisphere. It inhabits heterogeneous seascapes broadly varying in salinity and temperature. Here, we produced 74 whole genomes at intermediate coverage to study Harbour porpoise's evolutionary history and...
Article
Full-text available
Ultrastructural descriptions of the inner ear of highly sound-dependent mammalian species are lacking and needed to gain a better understanding of the hearing sense. Here, we present the first morphometric descriptions of the sensory cells of the inner ear in the harbor seal ( Phoca vitulina ), a mammal with broadly sensitive amphibious hearing. Sc...
Preprint
Full-text available
The harbour porpoise ( Phocoena phocoena ), a highly mobile cetacean species of the Northern hemisphere, inhabits basins that vary broadly in salinity, temperature, and food availability, and can drive divergent adaptation among local populations. To shed light on range-wide population structure and local adaptation, we generated ddRAD sequencing d...
Article
This is the printed version of final report to a Lower Saxonian goose research project in 2015-2019. It focusses on disturbance by hunting, air traffic, windturbines and agiculture, presents results to goose tracking in Greylags, Barnacles and Greater White-fronts, influence of geese on breeding waders, demograohy of shot Greylags in Lower Saxony,...
Article
Full-text available
The only native cetacean in German waters, the harbor porpoise (Phocoena phocoena), is impacted by numerous pathological lesions in the respiratory tract mainly caused by parasites or bacteria. Although harbor porpoises have been observed to not use their complete lung volume, it has not been studied whether this insufficiency leads to lower oxygen...
Article
This study investigates whether an exposure to two different received sound pressure levels at equal cumulative energy affects anti-predator behaviour and auditory detection thresholds of common roach (Rutilus rutilus) and sand goby (Pomatoschistus minutus) differently. This was examined in regard to a vessel slowdown as a management strategy to de...
Article
Full-text available
The assumed definitive host of the heartworm Acanthocheilonema spirocauda (Onchocerdidae; Filarioidea) is the harbour seal (Phoca vitulina). This filaroid nematode parasitizing in cardiac ventricles and blood vessel lumina of harbour seals (P. vitulina) has a low prevalence and seldom causes severe health impacts. The seal louse (Echinophthirius ho...
Chapter
Anthropogenic low-frequency continuous noise is on the rise in aquatic environments due to increased shipping, resource exploration, and infrastructure development. Tank-based studies using low-frequency continuous noise caused temporary hearing loss and behavioral alterations or masked relevant acoustic signals in some species. Various examples of...
Article
Full-text available
Abstract Across species, the skeletal system shares mutual functions, including the protection of inner organs, structural basis for locomotion, and acting as an endocrine organ, thus being of pivotal importance for survival. However, insights into skeletal characteristics of marine mammals are limited, especially in the growing skeleton. Harbor se...
Article
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The present study complements work on mixture effects measured with in vitro bioassays of passive equilibrium sampling extracts using the silicone polydimethylsiloxane (PDMS) in organs from marine mammals with chemical profiling. Blubber, liver, kidney and brain tissues of harbor porpoise (Phocoena phocoena), harbor seal (Phoca vitulina), ringed se...
Article
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Knowledge about parasite species of orcas, their prevalence, and impact on the health status is scarce. Only two records of lungworm infections in orca exist from male neonatal orcas stranded in Germany and Norway. The nematodes were identified as Halocercus sp. (Pseudaliidae), which have been described in the respiratory tract of multiple odontoce...
Article
Full-text available
Harbour seals are top predators in the North Sea and regarded as sentinels for ecosystem health. A few hundred also occur in adjacent estuaries, such as the Elbe estuary, Germany. However, only little is known about how these animals use this dynamic tidally influenced habitat, which has been under high anthropogenic pressure for decades. In this c...
Article
Full-text available
The North Sea faces intense ship traffic owing to increasing human activities at sea. As harbour seals (Phoca vitulina) are abundant top predators in the North Sea, it is hypothesised that they experience repeated, high-amplitude vessel exposures. Here, we test this hypothesis by quantifying vessel noise exposures from deployments of long-term soun...
Article
Full-text available
Arthropod ectoparasites of aquatic wildlife often have complex relationships with their host species that have developed over long evolutionary time scales. Specialist parasite occurrence might depend on these hosts’ distributions. Eurasian otter (Lutra lutra) populations are recovering in Northern German federal states, such as Schleswig-Holstein...
Article
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Longitudinal data on individual growth and seasonal changes in body mass, girth, and blubber thickness are rarely available for cetaceans, making it difficult to assess their population composition and individual nutritional condition. During different time intervals from 1997 to 2020, we collected longitudinal data on length, body mass, girth,and...
Article
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As one of the most abundant game species in Europe, European wild boar (Sus scrofa) populations prove highly adaptable to cultivated landscapes. The ongoing process of climate change and the high agricultural yields seem to further optimize the living conditions for this species. In long-term reproduction monitoring, we collected data on the body w...
Article
Echolocating toothed whales (odontocetes) capture fast-moving prey in dark marine environments, which critically depends on their ability to generate powerful, ultrasonic clicks. How their supposedly air-driven sound source can produce biosonar clicks at depths of >1000 meters, while also producing rich vocal repertoires to mediate complex social c...
Article
The southern tamandua (Tamandua tetradactyla) and the giant anteater (Myrmecophaga tridactyla) belong to the anteater family Myrmecophagidae and both species share basic morphological characteristics including the general features of reproductive organs. However, in female and male giant anteaters, persisting Wolffian and Müllerian ducts have been...
Article
Full-text available
Historically, the seals and harbour porpoises of the Baltic Sea and North Sea have been subjected to hunting, chemical pollutants and repeated mass mortalities, leading to significant population fluctuations. Despite the conservation implications and the zoonotic potential associated with viral disease outbreaks in wildlife, limited information is...
Article
We investigated elemental concentrations in muscle tissue of three species of dolphins incidentally bycaught off the KwaZulu-Natal coastline, South Africa. Thirty-six major, minor and trace elements were analysed in Indian Ocean humpback dolphin Sousa plumbea (n = 36), Indo-Pacific bottlenose dolphin Tursiops aduncus (n = 32) and the Common dolp...
Article
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The European brown hare (Lepus europaeus) is a quite adaptable species, but populations have been decreasing for several decades in different countries, including Germany. To investigate infectious diseases as possible influences on observed population decline in the German federal state Schleswig-Holstein, 118 deceased free-ranging European brown...
Article
Per- and polyfluorinated alkyl substances (PFAS) are a group of anthropogenic chemicals, which are not (fully) biodegradable and accumulate in different environmental compartments worldwide. A comprehensive, quantitative analysis - consisting of target analysis (66 different analytes, including e. g. ultrashort-chain perfluorinated carboxylic acids...
Article
Full-text available
The genus Arcanobacterium is constantly growing as novel species are identified. In particular, harbor seals have proven to be a common reservoir for bacteria of this genus. Here, we announce the complete genome sequence of another Arcanobacterium species—namely, Arcanobacterium pinnipediorum strain DSM 28752, isolated from a harbor seal.
Article
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The Svalbard white whale (Delphinapterus leucas) population is one of the smallest in the world, making it particularly vulnerable to challenges such as climate change and pathogens. In this study, serum samples from live captured (2001–2016) white whales from this region were investigated for influenza A virus (IAV) antibodies (Abs) (n = 27) and R...
Chapter
Full-text available
Man-made persistent pollutants (such as PCBs, pesticides and trace metals) reach aquatic organisms through the food chains. Pollutants are ingested and assimilated by smaller organisms, and their concentration in tissues increases from prey to predators. Being at the top of the food chains, marine mammals accumulate some of the highest environmenta...
Chapter
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There are various types of interactions between marine mammals and fisheries, and their presence in the same area inevitably leads to conflicts. Marine mammals may lose their lives as bycatch, which is the incidental catch of non-target species in fishing gear. On the other hand, some marine mammals specialise in feeding on fish caught in fishing g...
Chapter
Full-text available
In recent decades, global plastic consumption has rapidly increased. Large quantities of plastics enter the environment in various ways, often ending up in the oceans. Plastic debris is nowadays found in any aquatic ecosystems. Due to its long durability, plastics may drift around with ocean currents for decades. Nowadays, plastic debris can be fou...
Article
The giant anteater (superorder Xenarthra) is listed as Vulnerable by the International Union for Conservation of Nature (IUCN) and a low reproductive rate is considered one of the factors contributing to population decline of the species. Nevertheless, little is known on reproductive features in male giant anteaters and, in this regard, microscopic...
Article
Full-text available
Entrapment and subsequent drowning in fish fykes poses an anthropogenic mortality hazard to Eurasian otters (Lutra lutra). Different concepts on how to solve this problem have been debated in the past. To proactively prevent future fatal interactions and increase acceptance among fishers, this study tested two exit mechanisms for otters to safely e...
Article
Full-text available
Detailed post-mortem investigations including the auditory pathway are needed to advance our understanding of how underwater noise and other stressors affect hearing in cetaceans. A 12-year-old female porpoise ( Phocoena phocoena ) stranded alive in June 2021 at the German Baltic Sea coast and died some hours later. The most significant pathologica...
Preprint
The Harbour porpoise (Phocoena phocoena) is a highly mobile cetacean species which primarily occurs in coastal and shelf waters across the Northern hemisphere. It inhabits heterogeneous seascapes that vary broadly in salinity and temperature. Here we produced 74 whole genomes at intermediate coverage to study Harbour porpoise’s evolutionary history...
Preprint
The Harbour porpoise (Phocoena phocoena) is a highly mobile cetacean species which primarily occurs in coastal and shelf waters across the Northern hemisphere. It inhabits heterogeneous seascapes that vary broadly in salinity and temperature. Here we produced 74 whole genomes at intermediate coverage to study Harbour porpoise’s evolutionary history...
Article
Full-text available
Background In the last years, research on feline cardio-pulmonary parasites has considerably increased in Europe. Not only domestic cats (Felis catus), but also European wildcats (Felis silvestris) can serve as definitive hosts for these nematodes. The F. silvestris population in Germany has been growing rapidly within the last decades; therefore,...
Article
Full-text available
The Baltic and North Seas still contain large amounts of dumped munitions from both World Wars. The exposure of the munition shells to the seawater causes corrosion, which leads to the disintegration of shells and a leakage of energetic compounds, including the highly toxic 2,4,6-trinitrotoluene (TNT), and consequently threatening the marine enviro...
Article
Full-text available
The decline in the population of ring-necked pheasants (Phasianus colchicus) in northwestern Germany since 2007 raises questions about the underlying causes. We therefore studied the growth and immune status of ring-necked pheasant chicks dependent on different feed composition. Here, 490 ring-necked pheasant chicks were raised in five groups up to...
Article
Full-text available
High numbers of harbor porpoises (Phocoena phocoena) end up as bycatch in gillnets every year. Acoustic alarms (pingers) have been demonstrated to be an efficient mitigation tool to prevent bycatch of this species; however, little is known about the behavioral reactions of wild porpoises to pingers. This knowledge is important for optimizing the de...
Article
Full-text available
Apex predators are good indicators of environmental pollution since they are relatively long-lived and their high trophic position and spatiotemporal exposure to chemicals provides insights into the persistent, bioaccumulative and toxic (PBT) properties of chemicals. Although monitoring data from apex predators can considerably support chemicals’ m...
Article
The number of gray wolves (Canis lupus) in Lower Saxony, Germany, has increased since they recolonized the region in 2007, and developing appropriate management strategies requires accurate information on wolf habitat use. As research on space use and foraging ecology necessitates capture, tagging, and tracking of wolves, we evaluated the feasibili...
Article
Full-text available
Evaluating populational trends of health condition has become an important topic for marine mammal populations under the Marine Strategy Framework Directive (MSFD). In the Baltic Sea, under the recommendation of Helsinki Commission (HELCOM), efforts have been undertaken to use blubber thickness as an indicator of energy reserves in marine mammals....
Article
A polyphasic taxonomic study was performed on an unidentified previously described Arcanobacterium -like Gram-positive strain 2701 T isolated from an anal swab of a dead male harbour seal. Comparative 16S rRNA sequencing showed that the bacterium belonged to the genus Arcanobacterium in the family Arcanobacteriaceae . The genome sequence of the str...
Article
Full-text available
Native to South America, the coypu (Myocastor coypus) is an invasive alien species (IAS) of Union concern. It was introduced to Germany a hundred years ago and is considered established in all German federal states. Between January and February 2021, ground temperatures below −10° Celsius were recorded in Lower Saxony, Germany, for approximately tw...
Article
Full-text available
Detailed examinations of dolphins incidentally caught in bather protection nets along the KwaZulu‐Natal coastline, South Africa, over the past 10 years have yielded a dataset that can assist in the examination of external signs of bycatch. Investigating these external signs of fisheries interactions could aid in determining whether they could be us...
Poster
Full-text available
As mainly piscivorous top predator based at the end of the trophic chain, the Eurasian otter (Lutra lutra) is prone to bioaccumulation of environmental pollutants. Besides legacy compounds, the bulk of emerging pollutants with yet unknown impact on aquatic wildlife is a major concern for otters. Amongst them are anticoagulant rodenticides, which ar...
Article
Full-text available
Antimicrobial resistance is a global health threat that involves complex, opaque transmission processes in the environment. In particular, wildlife appears to function as a reservoir and vector for antimicrobial-resistant bacteria as well as resistance genes. In the present study, the occurrence of antimicrobial-resistant Escherichia coli was deter...
Conference Paper
Avila, I.C. & U. Siebert. 2022. Epidermal conditions by a visual assessment of humpback whales in the Colombian Pacific. Presented at the 19ª Reunión de Trabajo de Especialistas en Mamíferos Acuáticos de América del Sur y 13º Congreso de la Sociedad Latinoamericana de Mamíferos Acuáticos. Prai do Forte, Brasil. September 12-15, 2022.
Article
Full-text available
Wildlife habitats in general must provide foraging, hiding and resting places as well as sites for reproduction. Little is known about habitat selection of black grouse in the lowlands of Central Europe. We investigated habitat selection of seven radio tagged birds in an open heath and grassland area surrounded by dense pine forests in the northern...
Article
Full-text available
Analyses of sexual steroid hormones in wild boars are rarely described. Testosterone (T) and 17β-estradiol (E2) concentrations are useful to recognize sexual maturation. As threshold values for this species are unknown, additional parameters are required. A total of 127 blood samples from wild boar males were collected to measure T and E2. Age and...
Article
Full-text available
Knowledge of reproductive health in wild southern tamanduas (Tamandua tetradactyla; Mammalia: Myrmecophagidae) is fragmentary. During necropsies of roadkill xenarthran species in Brazil, a case of ovarian filariasis in an adult female southern tamandua was observed. Macroscopically, both ovaries were irregularly enlarged and had numerous smooth pro...
Article
Full-text available
The Common Eider (Somateria mollissima) inhabits the entire northern hemisphere. In northern Europe, the flyway population reaches from the southern Wadden Sea to the northern Baltic coast. The European population is classified as endangered due to declines in Common Eider numbers across Europe since 1990. In this study, we assessed 121 carcasses o...
Poster
Full-text available
Invasive Batrachochythrium dendrobatidis (Bd) has been detected in wild amphibians in central Europe in numerous cases. Ranaviruses have also been described, although less frequently. There are, however, still large gaps in our understanding of the influence of these pathogens on specific populations. The natterjack toad is an endangered species in...
Article
Full-text available
The Northern German Black Grouse metapopulation has been affected since decades by a sharply decline that has ultimately led to a reduced genetic variability. Gastrointestinal parasitoses are common among Black Grouse, but it is not clear if they have a further negative impact on the development of this already threatened metapopulation. Therefore,...
Article
Full-text available
The study of biological form is a vital goal of evolutionary biology and functional morphology. We review an emerging set of methods that allow scientists to create and study accurate 3D models of living organisms and animate those models for biomechanical and fluid dynamic analyses. The methods for creating such models include 3D photogrammetry, l...
Poster
Full-text available
As Germanys largest carnivore, gray seals seem to fill in the role as apex predator. They share the habitat with two other top predators – harbour seal (Phoca vitulina) and harbour porpoise (Phocoena phocoena). Whereas harbour seals are present in stable numbers in the German Wadden Sea and adjacent waters, the gray seal population is still recover...
Article
Full-text available
Antimicrobial-resistant bacteria pose a serious global health risk for humans and animals, while the role of wildlife in the dynamic transmission processes of antimicrobial resistance in environmental settings is still unclear. This study determines the occurrence of antimicrobial-resistant Escherichia coli in the free-living great cormorants (Phal...
Article
Full-text available
Large rivers like the Elbe or the Weser are periodically entered by harbor porpoises of the North Sea. They may even move 97 km upstream to the port of Hamburg, where their presence is highest in spring. This migration is believed to be related to important anadromous prey species travelling upstream for spawning. An acoustic flowmeter in the port...
Article
Full-text available
Long‐lived top predators shape biodiversity structure in their ecosystems and predator‐prey interactions are critical in decoding how communities function. Studies on the foraging ecology of seals and Eurasian otters in Western Europe are outdated and most studies solely performed traditional hard part analysis. Molecular metabarcoding can be used...
Chapter
The study and protection of environmental and human health is complex given the variety of anthropogenic and natural stressors threatening the well-being of exposed organisms. Researchers have turned to wild animals as sentinel species to study the critical questions relating to environmental chemical contamination and potential adverse health effe...
Article
Full-text available
Harbour porpoises are widely distributed in the North Atlantic and represent the most abundant cetacean species in the North and Baltic Seas. Spontaneous neoplasms are relatively rarely reported in cetaceans, and only little is known about neoplasia in harbour porpoises. Thus, archival material was reviewed for spontaneous neoplasms in harbour porp...
Article
Full-text available
We used in-tissue passive equilibrium sampling using the silicone polydimethylsiloxane (PDMS) to transfer chemical mixtures present in organs from marine mammals with lipid contents between 2.3-99 % into in vitro bioassays. Tissues from five harbor porpoises (Phocoena phocoena), one harbor seal (Phoca vitulina) and one orca (Orcinus orca) from the...
Article
Highly pathogenic avian influenza viruses of the H5N8 subtype have been circulating in Europe and Asia since 2016, causing huge economic losses to the poultry industry. A new wave of H5Nx infections has begun in 2020. The viruses mainly infect wild birds and waterfowl; from there they spread to poultry and cause disease. Previous studies have shown...
Technical Report
As stated by HELCOM Expert Group on Marine Mammals (EG MAMA; portal.helcom.fi, 2021), limited information is available on the occurrence, (eco)toxicity, and potential health effects of contaminants of emerging concern (CECs) in marine mammals. CECs are introduced into the environment by various anthropogenic activities andsome of these substances m...
Article
Full-text available
Primordial follicles are important for the reproduction cycle and, therefore, also for the survival of the whole population of a species. Mammals have a large pool of primordial follicles, and it is thought that this pool represents the total number of oocytes. The aim of the present study was to determine the total primordial follicle number of ju...