Resilience of a tropical sport fish population to a severe cold event varies across five estuaries in southern Florida

Abstract

Abstract. For species that are closely managed, understanding population resilience to environmental and anthropogenic disturbances (i.e., recovery trajectories across broad spatial areas) can guide which suite of management actions are available to mitigate any impacts. During January 2010, an extreme cold event in south Florida caused widespread mortality of common snook, Centropomus undecimalis, a popular sport fish. Interpretation of trends using fishery-independent monitoring data in five south Florida estuaries showed that changes in catch rates of adult snook (>500 mm standard length) varied between no effects postevent to large effects and 4-yr recoveries. The reasons for the variation across estuaries are unknown, but are likely related to differences in estuary geomorphology and habitat availability (e.g., extent of deep rivers and canals) and differences in the proportions of behavior contingents (i.e., segments of the population that use divergent movement tactics) that place snook in different areas of the estuary during winter. Emerging awareness of the presence of behavior contingents, identification of overwintering sites, and improvements of abundance indices in remote nursery habitats should provide a better understanding of population resilience to disturbance events for snook. Given that changes in the frequency of short-lived, severe cold events are currently unknown, the findings and management actions described here for a tropical species living at the edge of its distribution should be useful to scientists forecasting the effects of climate change.

Seagrass Habitats as Nurseries for Reef-Associated Fish: Evidence from Fish Assemblages in and Adjacent to a Recently Established No-Take Marine Reserve in Dry Tortugas National Park, Florida, USA

“…Without a long-term data set using Z-traps, it is difficult to say if the greater abundances of H. bivittatum, H. aurolineatum, and the smaller size classes of O. chrysurus and H. plumierii during fall 2009 were unusual. Differences in fish community structure between fall 2009 and spring 2010 could have been related to an extreme cold event during the winter of 2010 that caused massive mortality of patch reefs in the Florida Keys and subtropical fish species in various regions of Florida (Colella et al 2012, Stevens et al 2016). An additional possibility is that 2009 was an exceptionally good recruitment year, especially for the summer-spawning O.…”

Investigating Sub-tropical Community Resistance and Resilience to Climate Disturbance

“…Rehage et al (2016) attribute this spatial variation in resilience to differences in distance to warm water source populations. Likewise, Stevens et al (2016) found that following the 2010 cold spell in Florida, resistance of a tropical estuarine piscivore were similar across three of four estuaries but resilience varied, possibly an effect related to inter-estuary differences in geophysical structuring that may influence reproduction, recruitment, and juvenile survival. Thus, landscape features are an important consideration since they can influence both resistance and resilience.…”

“…In both Florida and China, mortality of tropical species was observed from latitudes 19°N, and 29°N, to latitudes of 24°N and 28°N, respectively (Chen et al 2016;Stevens et al, 2016, Kemp et al 2016. Despite the large footprint of the area affected by extreme cold spells, tropical species and sub-tropical community resistance and resilience vary across space.…”

“…For instance, Stevens et al (2016) Like resistance, sub-tropical community resilience can vary across spatial scales.…”

“…In South Florida, both cold spells and droughts drive substantial ecological change, ranging from almost complete population losses of tropical species from extreme cold spells, to drought-induced fires that can completely re-arrange landscapes (Beckage et al 2003;Stevens et al 2016). In 2010, an extreme cold spell affected South Florida, and one year later, a once-in-10-year drought desiccated the region.…”