Reproductive resilience of an estuarine fish in the eye of a hurricane.

Spatial and temporal patterns of spawning activity are important measures of resilience in fishes that directly link environmental disturbances with reproductive success. We acoustically monitored spawning in spotted seatrout (Cynoscion nebulosus) from April through September 2017 at 15 sites near Port Aransas, Texas, which coincided with the landfall of a category 4 hurricane (Harvey) on 25 August. Spawning sounds were recorded every day of the study across all sites and were also confirmed during the hurricane at two sites located within the eye of the storm. Daily spawning continued after the hurricane, but the onset of spawning shifted 2.12 h earlier for 5 days, after which it returned to the pre-storm schedule. These results illustrate the resilience of seatrout to intense, episodic disturbances and offer insights on the phenotypic plasticity of estuarine fishes to cope with projected increases in environmental variability.

The importance of spawning behavior in understanding the vulnerability of exploited marine fishes in the U.S. Gulf of Mexico.

The vulnerability of a fish stock to becoming overfished is dependent upon biological traits that influence productivity and external factors that determine susceptibility or exposure to fishing effort. While a suite of life history traits are traditionally incorporated into management efforts due to their direct association with vulnerability to overfishing, spawning behavioral traits are seldom considered. We synthesized the existing biological and fisheries information of 28 fish stocks in the U.S. Gulf of Mexico to investigate relationships between life history traits, spawning behavioral traits, management regulations, and vulnerability to fishing during the spawning season. Our results showed that spawning behavioral traits were not correlated with life history traits but improved identification of species that have been historically overfished. Species varied widely in their intrinsic vulnerability to fishing during spawning in association with a broad range of behavioral strategies. Extrinsic vulnerability was high for nearly all species due to exposure to fishing during the spawning season and few management measures in place to protect spawning fish. Similarly, several species with the highest vulnerability scores were historically overfished in association with spawning aggregations. The most vulnerable species included several stocks that have not been assessed and should be prioritized for further research and monitoring. Collectively, the results of this study illustrate that spawning behavior is a distinct aspect of fish ecology that is important to consider for predictions of vulnerability and resilience to fisheries exploitation.