Hans Slabbekoorn

Leiden University | LEI · Institute of Biology Leiden

The EU-funded SATURN project contributes to improve our understanding of the effects of ship noise on aquatic animals through several studies. Assessing the effects of underwater noise on aquatic animals is complex due to the diversity of taxa involved, each with their own sound sensitivity in terms of spectral and temporal aspects, as well as beha...

Long-term impact from prenatal noise exposure in birds should raise general concern

Acoustic deterrent devices are used to guide aquatic animals from danger or toward migration paths. At sea, moderate sounds can potentially be used to deter fish to prevent injury or death due to acoustic overexposure. In sound exposure studies, acoustic features can be compared to improve deterrence efficacy. In this study, we played 200–1600 Hz p...

Marine fish inhabit an acoustic world and are often exposed to anthropogenic noise. Natural sounds play an important role in spawning aggregations, finding prey, escaping predators and guiding spatial behavior. Noise pollution at sea includes the prominent presence of sounds from vessels, but also pile driving, seismic surveys, and explosions, whic...

Many animals produce vocal signals during agonistic interactions that convey their ability and motivation to escalate the conflict. Often, such disputes follow ritualized, sequential phases with increasing aggression, favouring the assessment of individuals' chances of winning. This allows for individuals to withdraw before getting involved in a se...

Noisy human activities at sea are changing the acoustic environment, which has been shown to affect marine mammals and fishes. Invertebrates, such as bivalves, have so far received limited attention despite their important role in the marine ecosystem. Several studies have examined the impact of sound on anti-predator behavior using simulated preda...

There is a global rise in anthropogenic noise and a growing awareness of its negative effects on wildlife, but to date the consequences for wildlife diseases have received little attention. In this paper, we discuss how anthropogenic noise can affect the occurrence and severity of infectious wildlife diseases. We argue that there is potential for n...

Human activities can be noisy, especially in urban areas, and affect animals detrimentally. Traffic noise may interfere with acoustic communication through masking and may yield noise‐dependent modification of acoustic signals. Such vocal flexibility in birds has been investigated most often for songs, but rarely for calls, even though calls are ty...

Anthropogenic sound has increasingly become part of the marine soundscape and may negatively affect animals across all taxa. Invertebrates, including bivalves, received limited attention even though they make up a significant part of the marine biomass and are very important for higher trophic levels. Behavioural studies are critical to evaluate in...

Underwater noise from human activities is now widely recognised as a threat to marine life. Nevertheless, legislation which directly addresses this source of pollution is lacking. The first (and currently only) example globally is Descriptor 11 of the Marine Strategy Framework Directive (MSFD), adopted by the European Union in 2008, which requires...

Predictable behaviour (or ‘behavioural stability’) might be favoured in certain ecological contexts, for example when representing a quality signal. Costs associated with producing stable phenotypes imply selection should favour plasticity in stability when beneficial. Repeatable among‐individual differences in degree of stability are simultaneousl...

Chronic traffic noise is increasingly recognised as a potential hazard to wildlife. Several songbird species have been shown to breed poorly in traffic noise exposed habitats. However, identifying whether noise is causal in this requires experimental approaches. We tested whether experimental exposure to chronic traffic noise affected parental beha...

Anthropogenic sound has been shown to affect marine animals across taxa. However, bivalves and other invertebrates have received limited attention, and most studies across taxa have focussed on immediate, rather than long-term, effects of sound. Most bivalves adopt a sessile or sedentary lifestyle and are therefore likely to be subject to frequent...

Offshore energy acquisition through the construction of wind farms is rapidly becoming one of the major sources of green energy all over the world. The construction of offshore wind farms contributes to the ocean soundscape as steel monopile foundations are commonly hammered into the seabed to anchor wind turbines. This pile driving activity causes...

Chronic traffic noise is increasingly recognised as a potential hazard to wildlife. Various songbird species, for example, have been shown to breed poorly in traffic noise exposed habitats. However, identifying whether noise is causal in this requires experimental approaches. We here tested whether experimental exposure to chronic traffic noise aff...

Standardization and reduction of variation is key to behavioural screening of animal models in toxicological and pharmacological studies. However, individual variation in behavioural and physiological phenotypes remains in each laboratory population and can undermine the understanding of toxicological and pharmaceutical effects and their underlying...

Vocal communication is often used to signal willingness to escalate into a physical fight during territorial conflicts. In songbirds, starting to sing when an opponent already sings (song overlapping) has been suggested to signal aggressive intent (willingness to escalate). We used a multiyear data set to test whether song overlapping predicts aggr...

The aquatic world of animals is an acoustic world as sound is the most prominent sensory capacity to extract information about the environment for many aquatic species. Fish can hear particle motion, and a swim bladder potentially adds the additional capacity to sense sound pressure. Combining these capacities allows them to sense direction, distan...

Anthropogenic noise in the oceans is disturbing marine life. Among other groups, pelagic fish are likely to be affected by sound from human activities, but so far have received relatively little attention. Offshore wind farms have become numerous and will become even more abundant in the next decades. Wind farms can be interesting to pelagic fish d...

Anthropogenic noise can interfere with animal behavior through masking of acoustic communication. In response to masking, animals may change their acoustic signals as an apparent adjustment strategy, but this may have a drawback on signal quality. Songs and calls may show noise-dependent changes in frequency and duration, which may yield some maski...

Birds communicate through acoustic variation in their songs for territorial defense and mate attraction. Noisy urban conditions often induce vocal changes that can alleviate masking problems, but that may also affect signal value. We investigated this potential for a functional compromise in a neotropical songbird: the bananaquit (Coereba flaveola)...

Background The effect of individual acoustic receiver contributions to animal positioning is a crucial aspect for the correct interpretation of acoustic positional telemetry (APT). Here, we evaluated the contribution of each receiver within two APT designs to the number of tag signals detected and the position accuracy of free-ranging Atlantic cod,...

Marine ambient sound levels have risen due to noisy human activities, such as shipping, fishing, seismic surveys and piling for windfarms. Marine mammals and fishes are two prominent taxonomic groups that are exposed to this noise pollution, which may experience detrimental effects at the population level. Acoustic effects on individual behaviour s...

Geophysical exploration of the seabed is typically done through seismic surveys, using airgun arrays that produce intense, low-frequency-sound pulses¹ that can be heard over hundreds of square kilometers, 24/7.²,³ Little is known about the effects of these sounds on free-ranging fish behavior.4, 5, 6 Effects reported range from subtle individual ch...

An anthropogenic cacophony Sound travels faster and farther in water than in air. Over evolutionary time, many marine organisms have come to rely on sound production, transmission, and reception for key aspects of their lives. These important behaviors are threatened by an increasing cacophony in the marine environment as human-produced sounds have...

Anthropogenic noise underwater is increasingly recognized as a pollutant for marine ecology, as marine life often relies on sound for orientation and communication. However, noise may not only interfere with processes mediated through sound, but also have effects across sensory modalities. To understand the mechanisms of the impact of anthropogenic...

In today's marine habitats, anthropogenic noise is widespread in space and time, affecting aquatic animal communities. Short-term exposure to noise is known to affect vital behaviours, such as the ability to evade predators. However, long-term noise pollution may lead to differences in short-term responses between naïve and experienced animals. We...

Anthropogenic sounds have spread across the biosphere, with threats from individual welfare to ecosystem health. Sounds are important to animals in both terrestrial and aquatic environments and detrimental effects have been shown across a wide range of taxa. Despite the ever-growing transformation of coastal lands by human activities, pollutant eff...

Anthropogenic sound can affect fish behaviour and physiology which may affect their well-being. However, it remains a major challenge to translate such effects to consequences for fitness at an individual and population level. For this, energy budget models have been developed, but suitable data to parametrize these models are lacking. A first step...

Background: An important aspect for the correct interpretation of Acoustic Positional Telemetry (APT) data concerns the effect of individual receiver contributions to animal positioning. The present study evaluated the contribution of each receiver within two APT designs to set-up efficiency and position accuracy of free-ranging Atlantic cod, throu...

Human settlements and activities alter the natural environment acoustically and visually. Traffic noise and street lights are two of the most prominent pollutants which may affect animal activity patterns. Birds in urban areas have been reported to sing nocturnally and to have an earlier dawn chorus compared to their rural counterparts. However, fe...

All songbirds have their own species-specific song, and vocal variety among individuals of the same species is used for communication. Some aspects of vocal variety have been shown to relate to sender characteristics and thus to convey a potential message to receivers. During playback experiments, individuals show different response patterns, which...

Anthropogenic underwater noise may negatively affect marine animals. Yet, while fishes are highly sensitive to sounds, effects of acoustic disturbances on fishes have not been extensively studied at the population level. In this study, we use a size-structured model based on energy budgets to analyse potential population-level effects of anthropoge...

Understanding the influence of changes in shipping intensity on the temporal and spatial distribution of underwater sound is needed for marine spatial planning. We introduce a practical approach for the estimation of underwater shipping sound for both past and future. Shipping sound has been identified as one of the largest contributors to the Dutc...

Aquatic animals use and produce sound for critical life functions, including reproduction. Anthropogenic noise is recognized as a global source of environmental pollution and adequate conservation and management strategies are urgently needed. It becomes therefore critical to identify the reproductive traits that render a species vulnerable to acou...

Virtually all organisms have adapted to the earth's day-night cycles by the evolution of endogenous rhythms that regulate most biological processes. Recent research has highlighted the role of glucocorticoids and the Glucocorticoid receptor (GR) in coordinating clock function across various levels of biological organisation. In the present study, w...

Energy intake and expenditure data are needed to estimate population level effects of anthropogenic sound on fish. We present an experimental design of a controlled behavioral experiment that allows to collect relatively long-term data (days) on Atlantic cod (Gadus morhua) during sound exposures. Data on the time spent foraging and swimming can be...

Group-living animals must communicate to stay in contact. In long-finned pilot whales, there is a trade-off between the benefits of foraging individually at depth and the formation of tight social groups at the surface. Using theoretical modelling and empirical data of tagged pairs within a group, we examined the potential of pilot whale social cal...

Traffic noise is on the rise worldwide. Birds have been reported to decrease in number and diversity near highways. This could be indirectly caused by traffic if birds avoid overall poorer habitat quality near highways or directly if birds actively avoid noisy conditions. To test whether traffic noise directly affects birds' spatial preferences, we...

Previously, adult zebrafish with a mutation in the gene encoding the glucocorticoid receptor (Gr) were demonstrated to display anxiety- and depression-like behavior that could be reversed by treatment with antidepressant drugs, suggesting that this model system could be applied to study novel therapeutic strategies against depression. Subsequent st...

Anthropogenic sources increasingly contribute to the underwater soundscape and this may negatively impact aquatic life, including fish. Anthropogenic sound may mask relevant sound, alter behaviour, physiology, and may lead to physical injury. Behavioural effect studies are often seen as critical to evaluate individual and population-level impact. H...

Noise pollution has spread over the entire globe: from the initial rumble in the Stone age, the invention of gun powder, and a steady rise during the industrial revolution, to a global acceleration in the second half of the 20th century. Hans Slabbekoorn highlights what we know about the impact of this acoustic climate change, on humans and animals...

Urbanization results in novel ecosystems with unique challenges. These may lead to problems during song learning or development and could result in the singing of atypical songs. During studies of Mountain Chickadees (Poecile gambeli) and urbanization in British Columbia, Canada, we observed males singing atypical songs along an urbanization gradie...

The ubiquitous anthropogenic low‐frequency noise impedes communication by masking animal signals. To overcome this communication barrier, animals may increase the frequency, amplitude and delivery rate of their acoustic signals, making them more easily heard. However, a direct impact of intermittent, high‐level aircraft noise on birds’ behaviour li...

Industrial and recreational activities have increased anthropogenic noise levels in aquatic habitats. Shipping activities, pile driving, seismic surveys, pumping systems, all produce sounds with different temporal patterns and can have detrimental effects on vertebrates and invertebrates. Moreover, light conditions have also changed in aquatic habi...

Underwater sound fields can be complex, both in open water and small tank environments. Here we measured 1) spatial variation in artificially elevated sound levels in a small fish tank for both particle motion and sound pressure. We confirmed that the ratio of pressure and particle motion deviated considerably from what would be expected in theoret...

Anthropogenic noise can mask avian vocalizations, and several urban‐dwelling species adjust frequency or amplitude of vocalizations in ways that appear to compensate for increased noise levels. Playback studies have investigated whether receivers differentiate between signals produced by rural and urban males, but it is difficult to determine wheth...

Offshore activities elevate ambient sound levels at sea, which may affect marine fauna. We reviewed the literature about impact of airgun acoustic exposure on fish in terms of damage, disturbance and detection and explored the nature of impact assessment at population level. We provided a conceptual framework for how to address this interdisciplina...

Underwater sound fields can be complex, both in open water and small tank environments. Here we measured 1) spatial variation in artificially elevated sound levels in a small fish tank for both particle motion and sound pressure. We confirmed that the ratio of pressure and particle motion deviated considerably from what would be expected in theoret...

A movie of weekly averaged sound maps is provided as a supplementary information. (https://www.sciencedirect.com/science/article/pii/S0269749118344932#mmc1)

Effective measures for protecting and preserving the marine environment require an understanding of the potential impact of anthropogenic sound on marine life. A crucial component is a proper assessment of the anthropogenic soundscape: which sounds are present where, when and how strong? We provide an extensive case study modelling the spatial, tem...

Background Many physiological processes in our body are controlled by the biological clock and show circadian rhythmicity. It is generally accepted that a robust rhythm is a prerequisite for optimal functioning and that a lack of rhythmicity can contribute to the pathogenesis of various diseases. Here, we tested in a heterogeneous laboratory zebraf...

In some bird species, males and females coordinate their songs into duets. Variation in the level of coordination in these displays may reflect cooperation or conflict. In grey-breasted wood-wrens, Henicorhina leucophrys, both sexes initiate duets with equal frequency, so duets are the product of both male and female behaviour, but the level of coo...

Aquatic animals live in an acoustic world in which they often rely on sound detection and recognition for various aspects of life that may affect survival and reproduction. Human exploitation of marine resources leads to increasing amounts of anthropogenic sound underwater, which may affect marine life negatively. Marine mammals and fishes are know...

Terrestrial mammals are found in all types of natural habitat, and they are also maintained in large numbers in captivity. Much of what is known about the anatomy and physiology of the peripheral auditory system has been learned by studying a variety of laboratory mammals and a smaller collection of exotic and domesticated species. The influence of...

Vocalizing birds are ubiquitous and often prominent in areas that are reached by noisy human activities. Birds have therefore been studied for the effects of man-made sound on song production and perception, physiological stress, distribution range, breeding density, and reproductive success. There are examples of birds that sing louder, higher, an...