@article {58197, title = {Acoustically advertising male harbour seals in southeast Alaska do not make biologically relevant acoustic adjustments in the presence of vessel noise}, year = {2020}, abstract = {

Aquatically breeding harbour seal (Phoca vitulina) males use underwater vocalizations during the breeding season to establish underwater territories, defend territories against intruder males, and possibly to attract females. Vessel noise overlaps in frequency with these vocalizations and could negatively impact breeding success by limiting communication space. In this study, we investigated whether harbour seals employed anti-masking strategies to maintain communication in the presence of vessel noise in Glacier Bay National Park and Preserve, Alaska. Harbour seals in this location did not sufficiently adjust source levels or acoustic parameters of vocalizations to compensate for acoustic masking. Instead, for every 1 dB increase in ambient noise, signal excess decreased by 0.84 dB, indicating a reduction in communication space when vessels passed. We suggest that harbour seals may already be acoustically advertising at or near a biologically maximal sound level and therefore lack the ability to increase call amplitude to adjust to changes in their acoustic environment. This may have significant implications for this aquatically breeding pinniped, particularly for populations in high noise regions.

}, keywords = {acoustic communication, harbour seals, marine mammals, Noise, vocalizations}, doi = {10.1098/rsbl.2019.0795}, url = {https://royalsocietypublishing.org/doi/10.1098/rsbl.2019.0795}, author = {Matthews, Leanna P. and Fournet, Michelle E. H. and Gabriele, Christine and Klinck, Holger and Parks, Susan E.} } @article {57571, title = {Acoustic crypsis in communication by North Atlantic right whale mother{\textendash}calf pairs on the calving grounds}, year = {2019}, abstract = {

Mammals with dependent young often rely on cryptic behaviour to avoid detection by potential predators. In the mysticetes, large baleen whales, young calves are known to be vulnerable to direct predation from both shark and orca predators; therefore, it is possible that mother\–calf pairs may show cryptic behaviours to avoid the attention of predators. Baleen whales primarily communicate through low-frequency acoustic signals, which can travel over long ranges. In this study, we explore the potential for acoustic crypsis, a form of cryptic behaviour to avoid predator detection, in North Atlantic right whale mother\–calf pairs. We predicted that mother\– calf pairs would either show reduced calling rates, reduced call amplitude or a combination of these behavioural modifications when compared with other demographic groups in the same habitat. Our results show that right whale mother\–calf pairs have a strong shift in repertoire usage, significantly reducing the number of higher amplitude, long-distance communication signals they produced when compared with juvenile and pregnant whales in the same habitat. These observations show that right whale mother\–calf pairs rely upon acoustic crypsis, potentially to minimize the risk of acoustic eavesdropping by predators.

}, keywords = {acoustic crypsis, baleen whale, eavesdropping, predator avoidance, right whale}, doi = {10.1098/rsbl.2019.0485}, url = {https://royalsocietypublishing.org/doi/10.1098/rsbl.2019.0485}, author = {Parks, Susan E. and Cusano, Dana A. and Sofie M. Van Parijs and Nowacek, Douglas P.} } @article {53360, title = {Frogs adapt to physiologically costly anthropogenic noise}, journal = {Proceedings of the Royal Society B: Biological Sciences}, volume = {285}, year = {2018}, month = {Sep-15-20182197}, pages = {20182194}, abstract = {

Human activities impose novel pressures on amphibians, which are experiencing unprecedented global declines, yet population-level responses are poorly understood. A growing body of literature has revealed that noise is an anthropogenic stressor that impacts ecological processes spanning sub-cellular to ecosystem levels. These consequences can impose novel selective pressures on populations, yet whether populations can adapt to noise is unknown. We tested for adaptation to traffic noise, a widespread sensory \“pollutant\”. We collected eggs of wood frogs (Rana sylvatica) from populations from different traffic noise regimes, reared hatchlings under the same conditions, and tested frogs for differences in sublethal fitness-relevant effects of noise. We show that prolonged noise impaired production of antimicrobial peptides associated with defence against disease. Additionally, noise and origin site interacted to impact immune and stress responses. Noise exposure altered leukocyte production and increased baseline levels of the stress-relevant glucocorticoid, corticosterone, in frogs from quiet sites, but noise-legacy populations were unaffected. These results suggest noise-legacy populations have adapted to avoid fitness-relevant physiological costs of traffic noise. These findings advance our understanding of the consequences of novel soundscapes, and reveal a pathway by which anthropogenic disturbance can enable adaptation to novel environments.

}, issn = {0962-8452}, doi = {10.1098/rspb.2018.2194}, url = {http://rspb.royalsocietypublishing.org/lookup/doi/10.1098/rspb.2018.2194https://syndication.highwire.org/content/doi/10.1098/rspb.2018.2194}, author = {Tennessen, Jennifer B. and Parks, Susan E. and Swierk, Lindsey and Reinert, Laura K. and Holden, Whitney M. and Rollins-Smith, Louise A. and Walsh, Koranda A. and Langkilde, Tracy} } @article {47324, title = {Upcall production by southern right whale ( Eubalaena australis) mother-calf pairs may be independent of diel period in a nursery area}, journal = {Marine Mammal Science}, year = {2017}, month = {Jan-02-2017}, doi = {10.1111/mms.12382}, url = {http://doi.wiley.com/10.1111/mms.12382}, author = {Dombroski, Julia R. G. and Parks, Susan E. and Groch, Karina R. and Flores, Paulo A. C. and Sousa-lima, Renata S.} }