Effects of Multiple Karenia brevis Red Tide Blooms on a Common Bottlenose Dolphin (Tursiops truncatus) Prey Fish Assemblage: Patterns of Resistance and Resilience in Sarasota Bay, Florida

Red tide blooms caused by the toxic dinoflagellate Karenia brevis are natural disturbance events that occur regularly along Florida’s west coast, often resulting in massive fish kills and marine mammal, seabird, and sea turtle mortalities. Limited prior work on the ecological effects of red tides suggests they play an important role in structuring ecosystem dynamics and regulating communities, however specific effects on prey populations and potential alterations to predator-prey interactions are unknown. We surveyed the prey fish assemblage of a top marine predator, the common bottlenose dolphin (Tursiops truncatus), in shallow seagrass habitat in Sarasota Bay, Florida, during 2004–2019, collecting data on prey density, species composition, K. brevis cell densities, and environmental variables. Across eight distinct red tide bloom events, resistance, resilience, and the ecological effects on the prey assemblage varied depending on bloom intensity, season, and frequency. Prey assemblage structure showed significant and distinct short-term shifts during blooms independent of the normal seasonal shifts in prey structure seen during non-bloom conditions. Canonical correspondence analysis indicated a strong influence of K. brevis density on assemblage structure. Blooms occurring primarily in the summer were associated with less initial prey resistance and higher than average annual catch per unit effort (CPUE) 1–3 years following bloom cessation, with bloom frequency prolonging the time needed to reach higher than average annual CPUE. Regardless of season, recovery to pre-bloom prey abundances occurred within 1 year. Sample-based rarefaction and extrapolation indicated significant differences in prey diversity among summer bloom events. This study is a first step in identifying differences in resistance, resilience, and the ecological effects of multiple red tide bloom events of various temporal scales and intensity on a dolphin prey assemblage. Improved understanding of the influence of red tides on estuarine structural dynamics and function can better inform management, and potentially guide mitigation efforts post-bloom.

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Severe Karenia brevis red tides influence juvenile bottlenose dolphin (Tursiops truncatus) behavior in Sarasota Bay, Florida

Marine Mammal Science ◽

10.1111/j.1748-7692.2010.00428.x ◽

2010 ◽

Vol 27 (3) ◽

pp. 622-643 ◽

Cited By ~ 27

Author(s):

Katherine A. McHugh ◽

Jason B. Allen ◽

Aaron A. Barleycorn ◽

Randall S. Wells

Keyword(s):

Bottlenose Dolphin ◽

Tursiops Truncatus ◽

Karenia Brevis ◽

Red Tides ◽

Sarasota Bay

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Persistent Effects of Begging on Common Bottlenose Dolphin (Tursiops truncatus) Behavior in an Estuarine Population

Aquatic Mammals ◽

10.1578/am.42.4.2016.531 ◽

2016 ◽

Vol 42 (4) ◽

pp. 531-541 ◽

Cited By ~ 3

Author(s):

Rebeccah A. Hazelkorn ◽

Bruce A. Schulte ◽

Tara M. Cox

Keyword(s):

Bottlenose Dolphin ◽

Tursiops Truncatus ◽

Common Bottlenose Dolphin

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Long-term monitoring for the surveillance of the conservation status of Tursiops truncatus in an EU Natura2000 site in the Mediterranean Sea. A pilot study in the Tuscan Archipelago

Mediterranean Marine Science ◽

10.12681/mms.24562 ◽

2021 ◽

Author(s):

ANTONELLA ARCANGELI ◽

ROBERTO CROSTI ◽

ILARIA CAMPANA ◽

LARA CAROSSO ◽

MARTINA GREGORIETTI ◽

...

Keyword(s):

Pilot Study ◽

Mediterranean Sea ◽

Bottlenose Dolphin ◽

Tursiops Truncatus ◽

Conservation Status ◽

Natura 2000 ◽

Research Network ◽

Habitats Directive ◽

Common Bottlenose Dolphin ◽

The Mediterranean

A pilot study, using the dataset from the research network ‘FLT Med Net’, which regularly monitors transborder regions in the Mediterranean Sea using ferries as platform for systematic surveys, was undertaken to assess common bottlenose dolphin range and population trends within the Natura 2000 EU marine site “Tutela del Tursiops truncatus”. The site was recently designated by the Tuscany Region (Italy) within the requirement of the EU Habitats Directive. In order to evaluate the conservation status of bottlenose dolphin according to the surveillance scheme of the Directive, two six-year periods (2007-2012; 2013-2018) were compared to assess trends in distribution-occurrence (range); Sightings Per Unit of Effort and Density (population). In total, 18146 NM were surveyed along two fixed transects, recording 90 sightings of Tursiops truncatus and a total of 268 specimens. Between the two periods, slight but not statistically significant differences were assessed, with decreasing trend in range and population of the species; no variation was detected in mean group sizes. Travelling was the most common behaviour, and juveniles were present in 20% of the sightings, concentrated during spring and summer. The consistent FLT Med Net dataset was found to be appropriate to evaluate important parameters for the assessment of trends in the conservation status of Tursiops truncatus at the Natura2000 site scale.

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Common bottlenose dolphin (Tursiops truncatus) problem solving strategies in response to a novel interactive apparatus

Behavioural Processes ◽

10.1016/j.beproc.2019.103990 ◽

2019 ◽

Vol 169 ◽

pp. 103990

Author(s):

L.K. Lauderdale ◽

L.J. Miller

Keyword(s):

Problem Solving ◽

Bottlenose Dolphin ◽

Tursiops Truncatus ◽

Common Bottlenose Dolphin ◽

Problem Solving Strategies

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Development and Validation of Monoclonal and Polyclonal Antibodies for the Detection of Immunoglobulin G of Bottlenose Dolphins (Tursiops Truncatus)

Journal of Veterinary Diagnostic Investigation ◽

10.1177/104063870701900502 ◽

2007 ◽

Vol 19 (5) ◽

pp. 465-470 ◽

Cited By ~ 12

Author(s):

Hendrik H. Nollens ◽

Linda G. Green ◽

Diane Duke ◽

Michael T. Walsh ◽

Beth Chittick ◽

...

Keyword(s):

Monoclonal Antibodies ◽

Polyclonal Antibody ◽

Immunoglobulin G ◽

Bottlenose Dolphin ◽

Tursiops Truncatus ◽

Bottlenose Dolphins ◽

Enzyme Linked Immunosorbent Assay ◽

Common Bottlenose Dolphin ◽

Circulating Antibodies ◽

The Common

Antibodies directed against species-specific immunoglobulin G (IgG) have a broad range of applications in serologic and immunologic research and in the development of clinical assays. Validated anti-IgG antibodies for marine mammal species are in short supply. The objective of this study was to produce and validate antibodies with specificity for IgG of the common bottlenose dolphin ( Tursiops truncatus). Bottlenose dolphin IgG was purified using protein G. Two mouse monoclonal antibodies and a rabbit polyclonal antibody were developed from mice and rabbits immunized with bottlenose dolphin IgG. The specificity of the monoclonal antibodies and the polyclonal antibody for bottlenose dolphin IgG was first verified by Western blot analysis and enzyme-linked immunosorbent assay (ELISA). For further validation, both monoclonal antibodies and the polyclonal antibody were incorporated in an indirect ELISA for the detection of the immune response of bottlenose dolphins to a vaccine antigen. Three bottlenose dolphins were immunized with a commercial Erysipelothrix rhusiopathiae vaccine, and serial blood samples were collected from all dolphins for measurement of levels of circulating antibodies. Seroconversion was observed in all 3 dolphins by use of both monoclonal antibodies and the polyclonal antibody. Circulating antibodies were detectable as early as 6 days after immunization in 1 dolphin. Peak antibody levels were detected 14 days after the immunization. The ability to detect seroconversion in all 3 immunized bottlenose dolphins firmly establishes the specificity of the monoclonal antibodies and the polyclonal antibody for IgG of the common bottlenose dolphin.

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