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Background: Animal-borne telemetry instruments (tags) have greatly advanced our understanding of species that are challenging to observe. Recently, non-recoverable instruments attached to cetaceans have increased in use, but these devices have limitations in data transmission bandwidth. We analyze trade-offs in the longevity, resolution, and continuity of data records from non-recoverable satellite-linked tags on deep-diving Ziphius cavirostris in the context of a behavioral response study of acute noise exposure. We present one data collection programming scheme that balances resolution and continuity against longevity to address specific questions about the behavioral responses of animals to noise exposure in experimental contexts. We compare outputs between two programming regimes on a commercially available satellite-linked tag: (1) dive behavior summary defined by conductivity thresholds and (2) depth time-series at various temporal resolutions. Results: We found that time-series data vary from the more precisely defined dives from a dive summary record data stream by an acceptable error range for our application. We determined a 5-min time-series data stream collected for 14 days balanced resolution with longevity, achieving complete or nearly complete diving records in 6 out of 8 deployments. We increased our data message reception rate several fold by employing a boat based data capture system. Finally, a tag deployed in a group concurrently with a high-resolution depth recorder showed high depth concordance. Conclusions: We present the conceptual framework and iterative process for matching telemetry tag programming to research questions that we used and which should be applicable to a wide range of studies. Although designing new hardware for our specific questions was not feasible at the time, we were able to optimize the sampling regime of a commercially available instrument to meet the needs of our research questions and proposed analyses. Nevertheless, for other study species or designs, the complicated intersection between animal behavior and bandwidth of telemetry systems can often create a severe mismatch among research questions, data collection, and analysis tools. More flexible programming and purpose-built instruments will increase the efficacy of these studies and increase the scientific yield relative to the inherently higher risk of invasive studies. [ABSTRACT FROM AUTHOR]

The long‐term viability of the Florida manatee is threatened in part by mortality from boat collisions. This study investigated manatee behavior during boat approaches to better understand factors that lead to manatee–boat collisions. Digital acoustic recording tags (DTAGs) and Argos‐linked GPS tags were deployed on 18 manatees in southwest Florida, and boat traffic around them was mapped. Suites of manatee behavioral, environmental, and boat‐related factors were recorded during opportunistic boat passes. We built generalized linear mixed models to determine which factors accounted for variation in occurrence, number, and timing of manatee behavioral changes during boat passes. Manatees responded to boats, changing their orientation, depth, and fluking behavior most often when a boat approached closely (<10 m). Manatees were also more likely to change their depth when not on a seagrass bed and when actively fluking before a boat pass. Boat speed did not affect the occurrence or intensity of manatee response. Compared to fast approaches, however, slower passes allowed the manatee more time to respond, and behavioral change occurred earlier relative to the time of the boat's closest point of approach. We conclude that faster boats likely pose a greater risk of collision with manatees than do slower boats. [ABSTRACT FROM AUTHOR]

For many marine organisms, especially large whales that cannot be studied in laboratory settings, our ability to obtain basic behavioral and physiological data is limited, because these organisms occupy offshore habitats and spend a majority of their time underwater. A class of multisensor, suction-cup-attached archival tags has revolutionized the study of large baleen whales, particularly with respect to the predatory strategies used by these gigantic bulk filter feeders to exploit abundant oceanic resources. By integrating these data with those from other disciplines, researchers have uncovered a diverse and extraordinary set of underwater behaviors, ranging from acrobatic diving maneuvers to extreme feeding events during which whales engulf volumes of prey-laden water that are much larger than their own body. This research framework not only improves our knowledge of the individual performance and behavior of these keystone predators but also informs our ability to understand the dynamics of complex marine ecosystems. [ABSTRACT FROM AUTHOR]

Detailed analyses of dolphin foraging behaviour have typically been difficult due to researchers' inability to observe entire foraging sequences. Using a new observational tool I was able to observe sequences of behaviours leading to successful prey captures, including behaviours not previously described in Sarasota Bay dolphins. I defined a set of specific foraging behaviours and demonstrated their position in successful sequences by analyzing the conditional probability of their occurrence based the occurrence of a capture. The sequences of behaviours dolphins used were not deterministic, and individual dolphins displayed different behavioural repertoires. Foraging behaviours occurred at rates of up to 0.5 per minute during general activity categories commonly used in odontocete research, and the current results could assist in the interpretation of these activities. [ABSTRACT FROM AUTHOR]

The article describe one of the most dramatic behavioral responses individuals have witnessed in several playback trials with natural and anthropogenic sounds to dozens of marine mammal species. Topics include examines three stimuli were presented several min apart and observers on the RHIB were blind to the playback sequence and identity of the calls used in each trial.

The trajectory of development and refinement of communication signals closely map physical and social development in many vertebrate species. Although marine mammals exhibit highly complex and diverse communication signals, asking similar questions about signal development can be challenging when dealing with long-lived species that roam widely at sea. North Atlantic right whales, a large baleen whale species, are intensely studied due to their endangered status. We examine whether right whale acoustic signals vary with the physical and social development of individuals from birth to adulthood using a latitudinal analysis. Data included 986 high-quality calls recorded from 49 individuals of known age spanning from 1 month to 37 years, with two individuals measured at different ages. Calls produced by calves younger than 1 year were easily distinguished by their short duration, a high degree of frequency modulation and a high percentage of nonlinear phenomena. Nonlinear phenomena within calls shifted from disorder (deterministic chaos) to increased control (biphonation and subharmonics) with increasing age. The overall percentage of calls containing nonlinear phenomena decreased with increasing age. Duration of the calls and calling bouts increased in direct correlation with age. Notably there was no clear indication of fixation in any of the measured parameters with age, with directional changes continuing over the entire age range studied. This study presents the first evidence that acoustic maturation does not stop at sexual maturity (∼9 years) in right whales and that refinement of calls continues through adulthood. Clear age-related voice cues have been documented in a range of terrestrial species with increases in call duration often reflecting increased stamina or condition in older adults. This study shows a similar trend in right whale sound production, with changes detectable across three-decade age range of available data. [ABSTRACT FROM AUTHOR]

Abstract: Whale entanglement in fishing gear is a global problem, and underwater ropes associated with this gear are often the cause of injuries that can lead to fatalities. Minke whales (Balaenoptera acutorostrata) are especially at risk because they are relatively small, widely distributed, and often occur in coastal habitats where many types of fishing gear are deployed. It is unknown whether minke whales can detect and avoid ropes associated with fishing gear. To address this question we conducted a series of field experiments to measure behavioral responses of nearshore minke whales to underwater ropes simulating crab and whelk fishing gear. We also investigated correlations between whale behaviors and specific environmental variables. Our methods involved both visual and acoustic monitoring of whale behaviors near experimental ropes and buoys of different colors. A remote sensing system was also used to simultaneously monitor oceanographic conditions, record underwater sounds, and capture underwater video of whales swimming near ropes. Minke whales (N=42) decreased their swimming velocity and altered their bearing when passing near experimental ropes, especially during trials with white and black ropes. Some minkes (N=7) also altered their underwater swimming trajectories when passing near ropes, and often appeared to produce low-frequency vocalizations. Collectively this information provides strong evidence that minke whales detect and react behaviorally to the presence of underwater ropes that simulate fishing gear in nearshore areas. We hypothesize that visual and perhaps passive acoustic sensory abilities may be the mechanisms behind these rope avoidance behaviors. We recommend that high contrast ropes (white and black) be used with fishing gear in coastal areas to help minimize entanglements of minke and perhaps other whale species. [Copyright &y& Elsevier]