02178nas a2200217 4500008004100000022001400041245009300055210006900148260001600217520146300233100001601696700002101712700002401733700002701757700001601784700002601800700002601826700002001852700002601872856006201898 2019 eng d a0824-046900aSeasonal variation in Arctic marine mammal acoustic detection in the northern Bering Sea0 aSeasonal variation in Arctic marine mammal acoustic detection in cDec-12-20203 a

Declines in Arctic sea ice cover are influencing the distribution of protected endemic marine mammals, many of which are important for local Indigenous Peoples, and increasing the presence of potentially disruptive industrial activities. Due to increasing conservation concerns, we conducted the first year‐round acoustic monitoring of waters off Gambell and Savoonga (St. Lawrence Island, Alaska), and in the Bering Strait to quantify vocalizing presence of bowhead whales, belugas, walruses, bearded seals, and ribbon seals. Bottom‐mounted archival acoustic recorders collected data for up to 10 months per deployment between 2012 and 2016. Spectrograms were analyzed for species‐typical vocalizations, and daily detection rates and presence/absence were calculated. Generalized additive models were used to model call presence as a function of time‐of‐year, sea surface temperature, and sea ice concentration. We identified seasonality in call presence for all species, corroborating previous acoustic and distribution studies, and identified finer‐scale spatiotemporal distribution via occurrence of call presence between different monitoring sites. Time‐of‐year was the strongest significant effect on call presence for all species. These data provide important information on Arctic endemic species' spatiotemporal distributions in biologically and culturally important areas within a rapidly changing Arctic region.

1 aChou, Emily1 aAntunes, Ricardo1 aSardelis, Stephanie1 aStafford, Kathleen, M.1 aWest, Leigh1 aSpagnoli, Christopher1 aSouthall, Brandon, L.1 aRobards, Martin1 aRosenbaum, Howard, C. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/mms.1265801782nas a2200181 4500008004100000022001400041245008200055210006900137260001600206300001600222490000800238520122000246100002001466700002001486700002101506700002201527856005101549 2018 eng d a0001-496600aDifferential hearing sensitivity in the adaptive background in a beluga whale0 aDifferential hearing sensitivity in the adaptive background in a cJan-09-2018 a1979 - 19790 v1443 a

The ability of the auditory system to maintain high differential sensitivity in the adaptive background was investigated in a beluga whale (Delphinapterus leucas). Adaptive background was a train of tone pips following one another at a rate of 1 kHz. Each pip consisted of eight carrier cycles of 64 kHz. Every 128 ms, the train of pips was interrupted for 16 ms and replaced with a test signal (16-ms series of the same tone pips as in the adaptive background, but of another level). The level of the test signals varied from -15 to + 20 dB relative the level of adaptive background. Evoked potentials (the rate following response, RFR) produced by the test signals were recorded. Increasing of adaptive level led to RFR thresholds growth. The 10-dB rising of adaptive signals intensity level led to 7.8 dB rising of test signal threshold. The response amplitude dependence on the test stimulus level was almost independent of the level of the adaptive background. Thus, the beluga’s auditory system displayed high sensitivity to the change in acoustic signal level in the high-level background. [This study was supported by the Russian Foundation for Basic Research (Grant No. 18-04-00088).]

1 aPopov, Vladimir1 aNechaev, Dmitry1 aSupin, Alexander1 aSysueva, Evgeniya uhttp://asa.scitation.org/doi/10.1121/1.506864301910nas a2200169 4500008004100000022001400041245010800055210006900163260001600232300001600248490000800264520133900272100002701611700002001638700003101658856005101689 2018 eng d a0001-496600aBurst-pulses in East Greenland narwhals: Further evidence for unique, individual-specific vocalizations0 aBurstpulses in East Greenland narwhals Further evidence for uniq cJan-09-2018 a1952 - 19520 v1443 a

In August 2013–2017, narwhals from Scoresby Sound, East Greenland, were instrumented with satellite-linked transmitters and acoustic sound and movement tags (AcousondeTM) over periods of up to 8 days. The records obtained provided continuous information on the whales’ acoustic behavior during foraging and social interactions. Burst-pulses were the most easily recognizable non-feeding vocalization. They tended to occur near the surface and were more common in records that displayed higher rates of clicks from other individuals, i.e., records that presumably would include more social interactions with other narwhals. Over 100 burst pulses detected in eight subjects were analyzed in terms of their overall length and their pattern of successive inter-click intervals (ICIs). While overall length could be somewhat variable, the succession of ICIs was unique for each whale and could therefore have an identity-carrying function, as the signature whistle does in bottlenose dolphins and other odontocetes. The occurrence of these individual-specific burst-pulses in time and space will be examined in relation to other factors provided by the tags, such as the time of day, whale depth, presence of conspecifics, and behavioral state. [Work sponsored in part by the Greenland Institute of Natural Resources.]

1 aBlackwell, Susanna, B.1 aTervo, Outi, M.1 aHeide-Jørgensen, Mads, P. uhttp://asa.scitation.org/doi/10.1121/1.506853501725nas a2200181 4500008004100000022001400041245010400055210006900159260001600228300001600244490000800260520114100268100002201409700002001431700002101451700002001472856005101492 2018 eng d a0001-496600aResponses of the auditory system of odontocetes to level changes of long lasting acoustical stimuli0 aResponses of the auditory system of odontocetes to level changes cJan-09-2018 a1741 - 17410 v1443 a

The effects of level changes of long lasting sound stimuli (tone pip trains) on evoked potentials (the rate following response, RFR) were investigated in a beluga whale (Delphinapterus leucas). The stimuli were of 64 kHz carrier frequency at levels from 80 to 140 dB re 1 μPa. During stimulation, the stimulus level either was kept constant (the steady-state stimulation) or was changed up/down by 20 or 40 dB every 1000 ms. After transition from a lower to upper stimulus level (increase), the response amplitude increased quickly and then decayed slowly. After transition from an upper to lower stimulus level (decrease), the response amplitude fell quickly and later recovered slowly. In the both cases, during the 1000 ms stimulus, the response amplitude almost reached that of the steady-state stimulus of the same level. The auditory system of the beluga (and, hypothetically, other odontocetes) may be characterized as quickly flexible and capable of quick adjustment of its responses to the current auditory scene. [This study was supported the Russian Science Foundation (Project No. 17-74-20107) awarded to E.V.S.]

1 aSysueva, Evgeniya1 aNechaev, Dmitry1 aSupin, Alexander1 aPopov, Vladimir uhttp://asa.scitation.org/doi/10.1121/1.506771900584nas a2200157 4500008004100000245014500041210006900186260001600255300001400271490000700285100001800292700002300310700001900333700002100352856005300373 2017 eng d00aVocalizations of captive beluga whales, Delphinapterus leucas: Additional evidence for contact signature “mixed” calls in belugas0 aVocalizations of captive beluga whales iDelphinapterus leucasi A cJan-07-2017 a889 - 9030 v331 aPanova, Elena1 aAgafonov, Alexandr1 aBelikov, Roman1 aMelnikova, Faina uhttp://doi.wiley.com/10.1111/mms.2017.33.issue-300536nas a2200145 4500008004100000245012100041210006900162260001600231300001400247490000700261100002900268700002200297700001800319856005300337 2017 eng d00aSpatial and temporal patterns in the calling behavior of beluga whales, Delphinapterus leucas, in Cook Inlet, Alaska0 aSpatial and temporal patterns in the calling behavior of beluga  cJan-01-2017 a112 - 1330 v331 aBlevins-Manhard, Rachael1 aAtkinson, Shannon1 aLammers, Marc uhttp://doi.wiley.com/10.1111/mms.2017.33.issue-1