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Details in birdsong parameters convey information about fitness, quality and motivational state of the signaller. Perception of these song details may affect decision making of receivers in territorial defence and mate choice. Whether the message in the song is perceived or not may have major consequences for the birds’ reproductive success. Consequently, birds may suffer fitness consequences from masking by other sounds in the environment. We conducted two different playback experiments to test whether song consistency, a sexually selected performance trait expressed in the temporal and spectral parameters of song, is perceived under different noise conditions. In the first experiment, we found that blue tits, Cyanistes caeruleus, are less able to assess the performance levels of song, but still detect the song stimuli under experimentally high broadband noise levels. Blue tits also responded with more songs overall, independent of song stimulus variation to playback of song stimuli under noisy conditions. When song stimulus variants were exposed simultaneously with a narrow band of noise in the second experiment, blue tits showed reduced capacity to discriminate only when the band of noise overlapped in frequency with the song. Results from this experiment support the notion that it is indeed the masking, rather than nonauditory effects of noise that cause the change in behaviour. Overall, our results show that there are noisy conditions that do not affect detection but still affect perception of information in the detailed structure of songs. Not being able to respond appropriately to songs that differ in performance level is likely to have negative fitness consequences and contribute to a detrimental impact of anthropogenic noise on individuals and populations.

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 noise impacts at three main stages of pathogen transmission and disease development: (i) the probability of preinfection exposure, (ii) infection upon exposure, and (iii) severity of postinfection consequences. We identify potential repercussions of noise pollution effects for wildlife populations and call for intensifying research efforts. We provide an overview of knowledge gaps and outline avenues for future studies into noise impacts on wildlife diseases.

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 serious fight. Birds are well known for the variety of information encoded in their vocalizations, sometimes including specific features that signal aggression. A particular case may be so-called ‘tret calls’ produced by chiffchaffs, Phylloscopus collybita, a song affix for which the communicative role is not well understood. Here, we describe the acoustic structure and use of tret calls during simulated conflicts using playback. Our results show that tret calls are a low-amplitude vocalization and that birds increased tret calling after playback stimulation, suggesting a role as an aggressive signal similar to soft song in other species. However, we did not find that the tret call rate predicted subsequent aggressive behaviour. Our analysis of song variation in response to playback suggested that birds respond to a simulated vocal competitor in two phases: a highly aggressive phase where syllable rate goes up, which is predictive of physical attack, while simultaneously tret call rate goes down, and a low-aggression phase, in which tret call rate goes up, while syllable rate returns to baseline levels. These stereotypic fluctuations in two acoustic features may be part of an advanced communication system to moderate aggression. Finally, our results show a seasonal increase in tret calling after birds arrive at their breeding grounds, which is in line with a role in territorial aggression. We also found a nonsignificant trend for more tret calls with increasing ambient noise levels, which may be due to increased stress and aggression under noisy conditions or reflect a masking avoidance strategy.

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 predators, but studies using live predators are scarce. In the current study, we examined the separate and combined effects of boat sound playback and predator cues of shore crabs (Carcinus maenas) on the behavior of mussels (Mytilus spp.). We examined the behavior of the mussels using a valve gape monitor and scored the behavior from the crabs in one of two types of predator test conditions from video footage to control for effects from potential, sound-induced variation in crab behavior. We found that mussels closed their valve gape during boat noise and with a crab in their tank, but also that the stimulus combination did not add up to an even smaller valve gape. The sound treatment did not affect the stimulus crabs, but the behavior of the crabs did affect the valve gape of the mussels. Future research is needed to examine whether these results stand in situ and whether valve closure due to sound has fitness consequences for mussels. The effects on the well-being of individual mussels from anthropogenic noise may be relevant for population dynamics in the context of pressure from other stressors, their role as an ecosystem engineer, and in the context of aquaculture.

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 exposure to the same anthropogenic sounds. For this reason, bivalves are an especially relevant taxonomic group to study with regards to potential long-term effects of sound. In the current study, we examined whether blue mussels ( Mytilus edulis ) habituate to repeated sound exposures and whether they recover quicker from a single pulse exposure than from a pulse train. We equipped individual mussels with sensors to monitor their valve gape and exposed them to repeated sound playback. We found that mussels responded to sound by partially closing their valves. This response was consistent and repeatable, and decayed over sequential exposures to the same sound stimulus. A stimulus specificity test, meant to determine whether the decayed response could be attributed to habituation or more general sensory adaptation, yielded interesting but ambiguous results. Additionally, we found no differences in the initial response and recovery (time to return to baseline levels) between mussels that were exposed to single pulses and pulse trains. Our results therefore show that mussels reduce responsiveness over sequential exposures and that mussels mostly respond to the onset of a pulse train. Future research is needed to determine whether mussels habituate

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 individual and potentially population-level impacts of noise and can be used to compare the effects of different sounds. In the current study, we examined the effect of impulsive sounds with different pulse rates on the valve gape behaviour and phytoplankton clearance rate of blue mussels (Mytilus spp.). We monitored the mussels’ valve gape using an electromagnetic valve gape monitor and their clearance rate using spectrophotometry of phytoplankton densities in the water. We found that the mussels’ valve gape was positively correlated with their clearance rate, but the sound exposure did not significantly affect the clearance rate or reduce the valve gape of the mussels. They did close their valves upon the onset of a pulse train, but the majority of the individuals recovered to pre-exposure valve gape levels during the exposure. Individuals that were exposed to faster pulse trains returned to their baseline valve gape faster. Our results show that different sound exposures can affect animals differently, which should be taken into account for noise pollution impact assessments and mitigation measures.

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 investigated the interaction between short-term and long-term sound exposure on theantipredator response of free-ranging sand gobies, Pomatoschistus minutus. We tested the effects of short-term boat noise playback on the response to a simulated predator strike in areas across a range of low to high long-term noise disturbance levels. Exposure to boat noise did not affect the startle response, time frozen or response latency of gobies to a predator stimulus. However, individuals exposed to short-term boat noise playback were absent from the experimental area for shorter periods after the predator strike than gobies exposed to the silent control. Moreover, gobies in long-term noisy habitats also stopped avoiding the area after the predator strike under silent control conditions. These changes point to a decreased magnitude in antipredator response, as a function of interacting short- and longer-term levels of disturbance. Thus, prey species alter their antipredator behaviour in ways that can potentially lead to higher mortality for individual prey. This could ultimately have implications at the level of the food web.

Oceans have become substantially noisier since the Industrial Revolution. Shipping, resource exploration, and infrastructure development have increased the anthrophony (sounds generated by human activities), whereas the biophony (sounds of biological origin) has been reduced by hunting, fishing, and habitat degradation. Climate change is affecting geophony (abiotic, natural sounds). Existing evidence shows that anthrophony affects marine animals at multiple levels, including their behavior, physiology, and, in extreme cases, survival. This should prompt management actions to deploy existing solutions to reduce noise levels in the ocean, thereby allowing marine animals to reestablish their use of ocean sound as a central ecological trait in a healthy ocean.

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 sound to its full extent, we also need to study cross-sensory interference. To study this, we examined the effect of boat sound playbacks on olfactory-mediated food finding behaviour of shore crabs. We utilized opaque T-mazes with a consistent water flow from both ends towards the starting zone, while one end contained a dead food item. In this way, there were no visual or auditory cues and crabs could only find the food based on olfaction. We did not find an overall effect of boat sound on food finding success, foraging duration or walking distance. However, after excluding deviant data from one out of the six different boat stimuli, we found that crabs were faster to reach the food during boat sound playbacks. These results, with and without the deviant data, seem to contradict an earlier field study in which fewer crabs aggregated around a food source during elevated noise levels. We hypothesise that this difference could be explained by a difference in hunger level, with the current T-maze crabs being hungrier than the free-ranging crabs. Hunger level may affect the motivation to find food and the decision to avoid or take risks, but further research is needed to test this. In conclusion, we did not find unequivocal evidence for a negative impact of boat sound on the processing or use of olfactory cues. Nevertheless, the distinct pattern warrants follow up and calls for even larger replicate samples of acoustic stimuli for noise exposure experiments.

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 provide evidence for perception, and thus meaning, of the vocal variety. Here, we tested the impact of two types of vocal variety: syllable diversity and syllable switching in the common chiffchaff, Phylloscopus collybita, in two separate playback experiments. We found that syllable diversity was a relatively fixed trait and that variation among individuals was likely to reflect some male quality triggering responses of different intensity. Higher rates of syllable switching did not elicit different responses but songs after playback showed that it is a dynamic trait, potentially contributing to motivational signalling together with other song parameters. The resolution of analyses in our experiments revealed subtle changes in vocal features over time in unprecedented detail. This approach unveiled an intricate combination of various vocal features during the response that may complement each other during vocal interactions. We believe future studies would benefit from the same resolution, through which one can explore advanced levels in animal communication.

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. However, behavioural responsiveness likely depends on context and characteristics of sound stimuli. We pose that ambient sound levels, signal-to-noise ratio (SNR), and pulse rate interval (PRI), could affect the behavioural response of fish. To study this, we experimentally exposed groups of tagged European seabass (Dicentrarchus labrax) to different impulsive sound treatments that varied in pulse level, elevated background level, SNR, and PRI. Upon sound exposure, the seabass increased their swimming depth. The variation in the increase in swimming depth could not be attributed to pulse level, background level, SNR or PRI. It may be that the current range of sound levels or PRIs was too narrow to find such effects.

Waterschap Amstel, Gooi en Vecht heeft vrije vismigratie hoog in het vaandel staan. Onderzoek naar de passeerbaarheid vindt regelmatig en op verschillende locaties plaats. Daaruit blijkt dat de passeerbaarheid van sommige werken voor aal minder is. Geluid lijkt daarbij een rol te spelen.

Anthropogenic sound in the marine environment can have negative consequences for marine fauna. Since most sound sources are intermittent or continuous, estimating how many individuals are exposed over time remains challenging, as this depends on the animals' mobility. Here we explored how animal movement influences how many, and how often, animals are impacted by sound. In a dedicated study, we estimated how different movement strategies affect the number of individual harbour porpoises Phocoena phocoena receiving temporary or permanent hearing loss due to underwater detonations of recovered explosives (mostly WWII aerial bombs). Geo-statistical distribution models were fitted to data from 4 marine mammal aerial surveys and used to simulate the distribution and movement of porpoises. Based on derived dose-response thresholds for temporary (TTS) or permanent threshold shifts (PTS), we estimated the number of animals affected in a single year. When individuals were free-roaming, an estimated 1200 and 24 000 unique individuals would suffer PTS and TTS, respectively. This equates to respectively 0.50 and 10% of the estimated North Sea population. In contrast, when porpoises remained in a local area, fewer animals would receive PTS and TTS (1100 [0.47%] and 15 000 [6.5%], respectively), but more individuals would be subjected to repeated exposures. Because most anthropogenic sound-producing activities operate continuously or intermittently, snapshot distribution estimates alone tend to underestimate the number of individuals exposed, particularly for mobile species. Hence, an understanding of animal movement is needed to estimate the impact of underwater sound or other human disturbance. © The authors 2016.

1 januari 2015, Contains fulltext : 151971.pdf (Publisher’s version ) (Closed access), Different individuals cope with stressors in different ways. Stress coping styles are defined as a coherent set of individual behavioral and physiological differences in the response to a stressor which remain consistent across time and context. In the present study, we have investigated coping styles in larval zebrafish (Danio rerio) at 8 days post-fertilization. Larvae were separated into two groups, according to the emergence sequence from a darkened into a novel well-lit environment, early (EE) and late (LE) emergers. We used brief periods of netting as a stressor. Swimming behavior and kinematics before and after netting stress were analyzed, as were whole-body cortisol levels before and at 10, 30 and 60 min after the stress event. The results show that general swimming activity was different between EE and LE larvae, with lower baseline cumulative distance and more erratic swimming movements in EE than in LE larvae. EE larvae showed a faster recovery to baseline levels after stress than LE larvae. Cortisol baseline levels were not different between EE and LE larvae, but peak levels after stress were higher and the recovery towards basal levels was faster in EE than in LE larvae. This study shows that coping styles are manifest in zebrafish larvae, and that behavior and swimming kinematics are associated with different cortisol responses to stress. A better understanding of the expression of coping styles may be of great value for medical applications, animal welfare issues and conservation.

1.Traffic affects large areas of natural habitat worldwide. As a result, the acoustic signals used by birds and other animals are increasingly masked by traffic noise. Masking of signals important to territory defence and mate attraction may have a negative impact on reproductive success. Depending on the overlap in space, time and frequency between noise and vocalizations, such impact may ultimately exclude species from suitable breeding habitat. However a direct impact of traffic noise on reproductive success has not previously been reported. 2.We monitored traffic noise and avian vocal activity during the breeding season alongside a busy Dutch motorway. We measured variation in space, time and spectrum of noise and tested for negative effects on avian reproductive success using long-term breeding data on great tits Parus major. 3.Noise levels decreased with distance from the motorway, but we also found substantial spatial variation independent of distance. Noise also varied temporally with March being noisier than April, and the daytime being noisier than night-time. Furthermore, weekdays were clearly noisier than weekends. Importantly, traffic noise overlapped in time as well as acoustic frequency with avian vocalization behaviour over a large area. 4.Traffic noise had a negative effect on reproductive success with females laying smaller clutches in noisier areas. Variation in traffic noise in the frequency band that overlaps most with the lower frequency part of great tit song best explained the observed variation. 5.Additionally, noise levels recorded in April had a negative effect on the number of fledglings, independent of clutch size, and explained the observed variation better than noise levels recorded in March. 6.Synthesis and applications. We found that breeding under noisy conditions can carry a cost, even for species common in urban areas. Such costs should be taken into account when protecting threatened species, and we argue that knowledge of the sp, 1.Traffic affects large areas of natural habitat worldwide. As a result, the acoustic signals used by birds and other animals are increasingly masked by traffic noise. Masking of signals important to territory defence and mate attraction may have a negative impact on reproductive success. Depending on the overlap in space, time and frequency between noise and vocalizations, such impact may ultimately exclude species from suitable breeding habitat. However a direct impact of traffic noise on reproductive success has not previously been reported. 2.We monitored traffic noise and avian vocal activity during the breeding season alongside a busy Dutch motorway. We measured variation in space, time and spectrum of noise and tested for negative effects on avian reproductive success using long-term breeding data on great tits Parus major. 3.Noise levels decreased with distance from the motorway, but we also found substantial spatial variation independent of distance. Noise also varied temporally with March being noisier than April, and the daytime being noisier than night-time. Furthermore, weekdays were clearly noisier than weekends. Importantly, traffic noise overlapped in time as well as acoustic frequency with avian vocalization behaviour over a large area. 4.Traffic noise had a negative effect on reproductive success with females laying smaller clutches in noisier areas. Variation in traffic noise in the frequency band that overlaps most with the lower frequency part of great tit song best explained the observed variation. 5.Additionally, noise levels recorded in April had a negative effect on the number of fledglings, independent of clutch size, and explained the observed variation better than noise levels recorded in March. 6.Synthesis and applications. We found that breeding under noisy conditions can carry a cost, even for species common in urban areas. Such costs should be taken into account when protecting threatened species, and we argue that knowledge of the sp

In dit document zijn de maatregelen duurzame gewasbescherming per gewas beschreven. Dit verslag beschrijft het werk van 2007 waarin de complete set aan maatregelen is opgesteld die bij kan dragen aan het verlagen van milieubelasting en de stimulering van geïntegreerde gewasbescherming. De maatregelen zijn ingedeeld in Good Practices, Best Practices, Kennisontwikkeling en Beperkt toepasbare maatregelen. De vollegrondsgroenten in deze rapportage betreffen asperge, aardbei, bladgewassen, peen, prei en spruitkool

Bijna iedere sportvisser zal het weten: als je te luidruchtig bent aan de waterkant gaat de vis ervandoor. Ondanks deze visserswijsheid zullen velen zich niet realiseren hoe belangrijk geluid voor vissen is. De menselijke activiteit op en rond de oppervlaktewateren van Nederland neemt sterk toe. Als gevolg hiervan zal ook de geluidsbelasting onder water navenant zijn toegenomen. Er is maar weinig bekend over de effecten van omgevingsgeluid op vissen. Reden voor de Universiteit van Leiden hier een uitgebreid literatuuronderzoek aan te wijden