Fishes use a variety of sensory systems to learn about their environments and to communicate. Of the various senses, hearing plays a particularly important role for fishes in providing information, ...often from great distances, from all around these animals. This information is in all three spatial dimensions, often overcoming the limitations of other senses such as vision, touch, taste and smell. Sound is used for communication between fishes, mating behaviour, the detection of prey and predators, orientation and migration and habitat selection. Thus, anything that interferes with the ability of a fish to detect and respond to biologically relevant sounds can decrease survival and fitness of individuals and populations.
Since the onset of the Industrial Revolution, there has been a growing increase in the noise that humans put into the water. These anthropogenic sounds are from a wide range of sources that include shipping, sonars, construction activities (e.g., wind farms, harbours), trawling, dredging and exploration for oil and gas. Anthropogenic sounds may be sufficiently intense to result in death or mortal injury. However, anthropogenic sounds at lower levels may result in temporary hearing impairment, physiological changes including stress effects, changes in behaviour or the masking of biologically important sounds.
The intent of this paper is to review the potential effects of anthropogenic sounds upon fishes, the potential consequences for populations and ecosystems and the need to develop sound exposure criteria and relevant regulations. However, assuming that many readers may not have a background in fish bioacoustics, the paper first provides information on underwater acoustics, with a focus on introducing the very important concept of particle motion, the primary acoustic stimulus for all fishes, including elasmobranchs. The paper then provides background material on fish hearing, sound production and acoustic behaviour. This is followed by an overview of what is known about effects of anthropogenic sounds on fishes and considers the current guidelines and criteria being used world‐wide to assess potential effects on fishes.
Most importantly, the paper provides the most complete summary of the effects of anthropogenic noise on fishes to date. It is also made clear that there are currently so many information gaps that it is almost impossible to reach clear conclusions on the nature and levels of anthropogenic sounds that have potential to cause changes in animal behaviour, or even result in physical harm. Further research is required on the responses of a range of fish species to different sound sources, under different conditions. There is a need both to examine the immediate effects of sound exposure and the longer‐term effects, in terms of fitness and likely impacts upon populations.
Anthropogenic (man-made) sound has the potential to harm marine biota. Increasing concerns about these effects have led to regulation and mitigation, despite there being few data on which to base ...environmental management, especially for fishes and invertebrates. We argue that regulation and mitigation should always be developed by looking at potential effects from the perspectives of the animals and ecosystems exposed to the sounds. We contend that there is currently a need for far more data on which to base regulation and mitigation, as well as for deciding on future research priorities. This will require a process whereby regulators and researchers come together to identify and implement a strategy that links key scientific and regulatory questions.
Much of the current regulation and mitigation of the effects of anthropogenic sound is based on a very limited dataset.Future regulation and mitigation must be approached from the perspective of the animals. Which sounds affect the animals adversely, and what is the nature of these effects?Considerable data (and funding to get that data) is needed, particularly for fishes and invertebrates, before regulation and mitigation can be properly applied.Regulators and investigators should work together to develop a plan of action that focuses on the most important questions, to inform ways to protect animals and develop appropriate mitigation and regulation, and to inform the most effective way(s) to answer those questions.Future work should focus on a limited number of species, key research questions, and experimental approaches that allow easy comparison of data across studies, species, and sound sources.
The underwater environment is filled with biotic and abiotic sounds, many of which can be important for the survival and reproduction of fish. Over the last century, human activities in and near the ...water have increasingly added artificial sounds to this environment. Very loud sounds of relatively short exposure, such as those produced during pile driving, can harm nearby fish. However, more moderate underwater noises of longer duration, such as those produced by vessels, could potentially impact much larger areas, and involve much larger numbers of fish. Here we call attention to the urgent need to study the role of sound in the lives of fish and to develop a better understanding of the ecological impact of anthropogenic noise.
In this paper we reconsider the designation of fishes as being either “hearing specialists” or “hearing generalists,” and recommend dropping the terms. We argue that this classification is only ...vaguely and variously defined in the literature, and that these terms often have unclear and different meaning to different investigators. Furthermore, we make the argument that the ancestral, and most common, mode of hearing in fishes involves sensitivity to acoustic particle motion via direct inertial stimulation of the otolith organ(s). Moreover, any possible pressure sensitivity is the result of the presence of an air bubble (e.g., the swim bladder), and that hearing sensitivity may be enhanced by the fish having a specific connection between the inner ear to a bubble of air. There are data showing that some fish species have a sensitivity to both pressure and motion that is frequency dependent. Thus such species could not possibly be termed as either hearing “generalists” or specialists,” and many more species probably could be classified in this way as well. Furthermore, we propose that the term “specialization” be reserved for cases in which a species has some kind of morphological connection or close continuity between the inner ear and an air bubble that affects behavioral sensitivity to sound pressure (i.e., an otophysic connection).
The expansion of shipping and aquatic industrial activities in recent years has led to growing concern about the effects of man-made sounds on aquatic life. Sources include (but are not limited to) ...pleasure boating, fishing, the shipping of goods, offshore exploration for oil and gas, dredging, construction of bridges, harbors, oil and gas platforms, wind farms and other renewable energy devices, and the use of sonar by commercial and military vessels. There are very substantial gaps in our understanding of the effects of these sounds, especially for fishes and invertebrates. Currently, it is almost impossible to come to clear conclusions on the nature and levels of man-made sound that have potential to cause effects upon these animals. In order to develop a better understanding of effects of man-made sound, this paper identifies the most critical information needs and data gaps on the effects of various sounds on fishes, fisheries, and invertebrates resulting from the use of sound-generating devices. It highlights the major issues and discusses the information currently available on each of the information needs and data gaps. The paper then identifies the critical questions concerning the effects of man-made sounds on aquatic life for which answers are not readily available and articulates the types of information needed to fulfill each of these drivers for information—the key information gaps. Finally, a list of priorities for research and development is presented.
There are substantial interspecific differences in the morphology of the ears of the more than 34 000 living fish species. However, almost nothing is known about the functional significance of these ...differences. One reason is that most comparative studies have been conducted on shallow-water species with far less focus on the numerous species that inhabit the depths of the oceans. Thus, to get a better sense of ear diversity in fishes and its potential role in hearing, this study focuses on the saccule and lagena, the primary auditory end organs, in six species of the family Macrouridae (rattails), a large group of fishes that typically inhabit depths from 1000 to 4000 m. The inner ears and, particularly, the saccules and lagenae in these species are large with the saccule resembling that of other Gadiformes. The lagenae of all macrourids studied here have serrated edge otoliths and highly diverse hair cell ciliary bundle shapes. The differences found in the inner ear anatomy of macrourids likely reflect the sensory advantages in different habitats that are related to the benefits and constraints at different depths, the fish's particular lifestyle, and the trade-off among different sensory systems.
For over 50 years, Richard R. (Dick) Fay made major contributions to our understanding of vertebrate hearing. Much of Dick's work focused on hearing in fishes and, particularly, goldfish, as well as ...a few other species, in a substantial body of work on sound localization mechanisms. However, Dick's focus was always on using his studies to try and understand bigger issues of vertebrate hearing and its evolution. This article is slightly adapted from an article that Dick wrote in 2010 on the closure of the Parmly Hearing Institute at Loyola University Chicago. Except for small modifications and minor updates, the words and ideas herein are those of Dick.
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