UNF Digital Commons UNF Graduate Theses and Dissertations Student Scholarship 2013 The pS acial and Temporal Community Structure of Ichthyoplankton in a Northeast Florida Estuary : A Study of Ingress at a Faunal Boundary Breanna Korsman University of North Florida Suggested Citation Korsman, Breanna, "The pS acial and Temporal Community Structure of Ichthyoplankton in a Northeast Florida Estuary : A Study of Ingress at a Faunal Boundary" (2013). UNF Graduate Theses and Dissertations. 452. https://digitalcommons.unf.edu/etd/452 This Master's Thesis is brought to you for free and open access by the Student Scholarship at UNF Digital Commons. It has been accepted for inclusion in UNF Graduate Theses and Dissertations by an authorized administrator of UNF Digital Commons. For more information, please contact Digital Projects. © 2013 All Rights Reserved T H E SPA T I A L A ND T E MPO R A L C O M M UNI T Y ST RU C T UR E O F I C H T H Y OPL A N K T O N IN A N O R T H E AST F L O RID A EST U A R Y: A ST UD Y O F IN G R ESS A T A F A UN A L B O UND A R Y Breanna Marie Korsman A thesis submitted to the Department of Biology in partial fulfillment of the requirements for the degree of Master of Science in Biology University of North Florida August 2013 C E R T I F I C A T E O F APPR O V A L The Spatial and Temporal Community Structure of Ichthyoplankton in a Northeast Florida Estuary: A Study of Ingress at a Faunal Boundary By Breanna Marie Korsman Approved by the thesis committee: Date _____________________________________ ____________________ Dr. Matthew E. Kimball, Committee Chair _____________________________________ ____________________ Dr. Courtney T. Hackney _____________________________________ ____________________ Dr. Eric G. Johnson _____________________________________ ____________________ Dr. Frank J. Hernandez Accepted for the Department of Biology: ______________________________________ ____________________ Dr. Daniel C. Moon, Chair Accepted for the College of A rts and Sciences: _______________________________________ ____________________ Dr. Barbara A. Hetrick, Dean Accepted for the University: __________________________________________ ____________________ Dr. Len Roberson, Dean of the Graduate School ii A C K N O W L E D G E M E N TS Foremost, I would like to thank my advisor Dr. Matt Kimball for providing guidance in designing and carrying out the project that would become my M.S. thesis. Your motivation and high expectations are qualities that I hope to carry with me through the rest of my career. Additional thanks go out to my committee members: Dr. Courtney Hackney, Dr. Eric Johnson and Dr. Frank Hernandez. Thanks for listening to theories and ideas, and for providing great advice on data analysis. Frank ± your lab at DISL provided an excellent environment for someone just beginning to learn how to identify larval fish. Thanks to all of you! Thanks to everyone who helped make my field work possible. Wendy Eash- Loucks, Tom Harding, and the rest of the research staff at the Guana-Tolomato-Matanzas NERR were instrumental in the process. Kurt Foote, Andrew Rich, and Sam Adukiewicz ± thanks so much for working with me in establishing and gaining access to my field sites. Your support is appreciated! To my regulars in the field: Blake Thomas, Cora Johnston and Jessica Landkrohn ± thank you so much! You all put in more than your fair share of early mornings, and helped make the work fun. Thanks as well to all of the rest of my volunteers. Many hours of sleep were given up in order to help me complete this project. iii T A B L E O F C O N T E N TS List of Tables «««««««««««««««««««««««« v List of Figures ««««««««««««««««««««««««. vii Abstract «««««««««««««««««««««««««« x Introduction ««««««««««««««««««««««««« 1 ObjecWLYHV««««««««««««««««««««««« 5 Methods ««««««««««««««««««««««««««« 6 Study Area ««««««««««««««««««««««« 6 General Field Sampling Methodology «««««««««««« 8 7ULDO6DPSOLQJ0HWKRGRORJ\«««««««««««««««« 9 Data Analysis «««««««««««««««««««««« 11 Results ««««««««««««««««««««««««««« 12 (QYLURQPHQWDO9DULDEOHV««««««««««««««««« 12 7ULDO6DPSOLQJ««««««««««««««««««««« 13 Standard Sampling «««««««««««««««««««« 14 Discussion «««««««««««««««««««««««««« 19 Tables and Figures «««««««««««««««««««««« 32 Literature Cited ««««««««««««««««««««««« 50 Curriculum Vitae ««««««««««««««««««««««« 57 iv List of Tables: Table 1. Summary of results from paired t-tests on species richness and larval density values from diel, depth, duration, and location sampling protocols. Mean values of density (number of fish / 100 m3) and species richness (taxa / sample) are presented (± 1 SE). Diel, depth, and duration sampling took place at both inlets and data were combined. Location sampling occurred only at St. Augustine inlet. Table 2. Average monthly densities as number of larvae per 100 m3 of all taxa collected with a 1 mm mesh plankton net ingressing into the GTM estuary through the St. Augustine inlet between March 2012 and February 2013. Abundance rankings were calculated for the St. Augustine inlet and the Matanzas inlet (SA Rank, M Rank) for all taxa represented by > 5 individuals. Rare taxa (in rankings = R) were those represented E\LQGLYLGXDOV7D[DFROOHFWHGRQO\DWWKH0DWDQ]DVLQOHW RUWKH6W$XJXVWLQH inlet (^) are identified (in rankings, NC = no catch). Selected mixed taxa were exempted (E) from abundance rankings. Monthly larval densities represent sums of mean densities and were not used in statistical analyses. Table 3. Average monthly densities as number of larvae per 100 m3 of all taxa collected with a 1 mm mesh plankton net ingressing into the GTM estuary through the Matanzas inlet between March 2012 and February 2013. Abundance rankings were calculated for the St. Augustine inlet and the Matanzas inlet (SA Rank, M Rank) for all taxa represented by > 5 individuals. Rare taxa (in rankings = R) were tKRVHUHSUHVHQWHGE\ v individuals. Taxa collected only at the Matanzas inlet (*) or the St. Augustine inlet (^) are identified (in rankings, NC = no catch). Selected mixed taxa were exempted (E) from abundance rankings. Monthly larval densities represent sums of mean densities and were not used in statistical analyses. Table 4. Summary (expressed as a percentage of the total catch along with rank in parentheses) of the dominant families of ichthyoplankton collected ingressing into the Guana-Tolomato-Matanzas estuary during the March 2012 ± February 2013 study period, along with summaries of the dominant families from other similar surveys elsewhere in the South Atlantic Bight presented geographically from north to south. Family groups representing a negligible portion of the overall catch (*) or not caught (--) are indicated. Percent shared taxa refers to the proportion of total taxa shared with the present study. vi List of Figures: Figure 1. The St. Augustine and Matanzas inlets of the Guana-Tolomato-Matanzas estuary along the US Atlantic coast in northeast Florida. Primary ichthyoplankton sampling locations for each inlet are marked with stars. Figure 2. Mean (± 1 SE) temperature, salinity and dissolved oxygen (D.O.) for the GTM estuary March 2012 through February 2013. Data for the inlets were pooled, as no major differences existed between them during any sampling event (Kruskal-Wallis, temp: p = 0.954, salinity: p = .193, dissolved oxygen: p = .273). Figure 3. Monthly average species richness (taxa sample-1) and monthly average density (number of fish / 100 m3; ± 1 SE), for the Matanzas inlet (filled bars) and St. Augustine inlet (open bars) between March 2012 and February 2013. Note that the y-axis scales differ. Figure 4. Spatial differences demonstrated by non-metric multidimensional scaling in ichthyoplankton community structure at each of the two inlets that open to the Guana- Tolomato-Matanzas estuary, FL. Collections were taken between March 2012 and February 2013 with a 1 mm mesh plankton net. Each data point represents the density and diversity of the larval fish assemblage by month for each inlet. Ovals classify monthly assemblages into seasonal groups based on degree of similarity. Data were fourth root transformed prior to analyses. Similarity: 45, 2-D stress: 0.1 vii Figure 5. Temporal species associations for collections made at the inlets connecting the Atlantic Ocean with the Guana-Tolomato-Matanzas estuary, FL between March 2012 and February 2013, as demonstrated by non-metric multidimensional scaling. Collections were taken with a 1 mm mesh plankton net. Each data point represents the density of a single species by month for the two inlets combined. Species clustered together were often collected together. Data were fourth root transformed prior to analyses. Similarity: 50, 2-D stress: 0.1. Figure 6. Winter-recruiting taxa mean larval concentrations (number of fish / 100 m3; ± 1 SE). Total numbers of scaled individuals and mean standard length (SL) given for abundant winter-recruiting taxa entering the GTM estuary between March 2012 and February 2013. Mean length is reported as standard length (mm). Note that the y-axis scales vary. Figure 7. Summer-recruiting taxa mean larval concentrations (number of fish / 100 m3; ± 1 SE). Total numbers of scaled individuals and mean standard length (SL) given for abundant summer-recruiting taxa entering the GTM estuary between March 2012 and February 2013. Mean length is reported as standard length (mm). Note that the y-axis scales vary. Figure 8. Year-round-, spring-, and fall-recruiting mean larval concentrations (number of fish / 100 m3; ± 1 SE). Total numbers of scaled individuals