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In coastal waters, anthropogenic activity and its associated sound have been shown to negatively impact aquatic taxa that rely on sound signaling and reception for navigation, prey location, and intraspecific communication. The oyster toadfish Opsanus tau depends on acoustic communication for reproductive success, as males produce ‘boatwhistle’ calls to attract females to their nesting sites. However, it is unknown if in situ vessel sound impacts intraspecific communication in this species. Passive acoustic monitoring using a 4-hydrophone linear array was conducted in Eel Pond, a small harbor in Woods Hole, MA, USA, to monitor the calling behavior of male toadfish. The number of calls pre- and post-exposure to vessel sound was compared. Individual toadfish were localized, and their approximate sound level exposure was predicted using sound mapping. Following exposure to vessel sound, the number of calls significantly decreased compared to the number of calls pre-exposure, with vessel sound overlapping the frequency range of male toadfish boatwhistles. This study provides support that anthropogenic sound can negatively affect intraspecific communication and suggests that in situ vessel sound has the ability to mask boatwhistles and change the calling behavior of male toadfish. Masking could lead to a reduction in intraspecific communication and lower reproductive efficiency within the Eel Pond toadfish population. 

The ability to exert self-control varies within and across taxa. Some species can exert self-control for several seconds whereas others, such as large-brained vertebrates, can tolerate delays of up to several minutes. Advanced self-control has been linked to better performance in cognitive tasks and has been hypothesized to evolve in response to specific socio-ecological pressures. These pressures are difficult to uncouple because previously studied species face similar socio-ecological challenges. Here, we investigate self-control and learning performance in cuttlefish, an invertebrate that is thought to have evolved under partially different pressures to previously studied vertebrates. To test self-control, cuttlefish were presented with a delay maintenance task, which measures an individual's ability to forgo immediate gratification and sustain a delay for a better but delayed reward. Cuttlefish maintained delay durations for up to 50–130 s. To test learning performance, we used a reversal-learning task, whereby cuttlefish were required to learn to associate the reward with one of two stimuli and then subsequently learn to associate the reward with the alternative stimulus. Cuttlefish that delayed gratification for longer had better learning performance. Our results demonstrate that cuttlefish can tolerate delays to obtain food of higher quality comparable to that of some large-brained vertebrates.