Understanding the implications of environmental disturbance is of growing importance as climate change and extreme weather events increasingly threaten estuaries and other coastal ecosystems. Among species at risk in estuarine habitats, sport fishes are of particular interest to conservation and management agencies, because of their ecological and economic value. Here, we evaluate the effects of Hurricane Harvey on the abundance, diet, and body condition of age-0 red drum (Sciaenops ocellatus) and spotted seatrout (Cynoscion nebulosus) in Powderhorn Lake, a nearshore estuary in Texas, USA. Catch data from seines indicated that the abundances of age-0 red drum and spotted seatrout were not affected by the hurricane in the study system, but stomach contents and morphometric data show that diet and body condition changed after the event. Both species exhibited declines in body condition based on weight-length ratios, and diets included a greater proportion of invertebrates (i.e., shrimp, crab) postdisturbance, which may have been attributed to changes in fish assemblage structure within the estuary. Trophic niche overlap between age-0 red drum and spotted seatrout also decreased by up to 50% after the event, potentially serving as a mechanism to reduce competition in response to decreased prey availability. Thus, while more easily measured indicators of resistance/ resilience (i.e., abundance) did not indicate effects of Hurricane Harvey on sport fishes in Powderhorn Lake, body condition and diet suggest impacts were observed among age-0 fish. Declines in body condition and greater reliance on crustacean prey could have implications for survival, fitness, and harvestability, particularly if more energy is allocated to maintenance during recovery, rather than growth.

Historically, birdsong research has been biased towards song of male birds at dawn and during the day, even though some diurnal birds sing at night. To address this gap, we studied how song in the willie wagtail, Rhipidura leucophrys—a diurnal species with prolific male‐specific nocturnal song during the breeding season—varies with time of day, breeding status and simulated intrusions. We recorded male nocturnal and dawn song over three breeding seasons and examined how this related to fertile and non‐fertile breeding stages of females. To test whether song functions for territory defence, we simulated territorial intrusion experimentally in both sexes with daytime and nighttime playback of male and female song. To test whether nocturnal song could function for mate guarding or post‐pairing mate attraction, we describe the mating system of willie wagtails using molecular genetic methods. We showed that both nocturnal and day song of male willie wagtails has roles in mate attraction and territory defence, while day song by females functioned primarily for territorial defence. Males increased song behaviour during fertile periods of resident females, suggesting possible roles in mate stimulation and mate guarding. Males and females responded similarly to simulated daytime intrusions and no differences were seen in male responses dependent on the time of day. We found 10%–14% of offspring were fathered by extra‐pair males, suggesting song may also function for mate guarding and post‐pairing mate attraction. In a species with small repertoires and simple songs like the willie wagtail, differences between males in overall song output achieved through nocturnal singing may be important in mate attraction and territory defence.