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ASSESSING THE IMPACT OF OYSTER REEF AND LIVING SHORELINE RESTORATION ON MACROINVERTEBRATE COMMUNITY ASSEMBLAGES IN MOSQUITO LAGOON, FLORIDA
Title
ASSESSING THE IMPACT OF OYSTER REEF AND LIVING SHORELINE RESTORATION ON MACROINVERTEBRATE COMMUNITY ASSEMBLAGES IN MOSQUITO LAGOON, FLORIDA.
Creator
Searles, Adam, Cook, Geoffrey, University of Central Florida
Abstract / Description
As the world continues to experience substantial rates of habitat loss, habitat restoration has become of prime interest to ecologists worldwide. Restoration has shown to be successful in recovering targeted components of certain ecosystems but it is important to achieve a holistic understanding of the resulting ecological impacts it has on communities. To address this, four oyster reefs and three living shorelines were restored during the summer of 2017. These sites, along with four dead...
Show moreAs the world continues to experience substantial rates of habitat loss, habitat restoration has become of prime interest to ecologists worldwide. Restoration has shown to be successful in recovering targeted components of certain ecosystems but it is important to achieve a holistic understanding of the resulting ecological impacts it has on communities. To address this, four oyster reefs and three living shorelines were restored during the summer of 2017. These sites, along with four dead oyster reefs, four living oyster reefs, and three undisturbed (control) living shorelines, were sampled before restoration and regularly post-restoration for one year using lift nets. Macroinvertebrates were collected and enumerated in the lab. Diversity indices, community composition, and similarity percentages were then calculated and compared across treatments, time, and treatment-by-time. Live reefs displayed significantly higher species richness and Shannon diversity than restored and dead reefs. Simpson diversity did not differ between live and restored oyster reefs but both were significantly higher than dead reefs. Though not statistically detectable, species richness and Shannon diversity on restored reefs were relatively similar to dead reefs before restoration but became increasingly similar to live reefs over the course of the study. Additionally, analyses revealed significantly different community compositions between live reefs and restored reefs, as well as between live and dead reefs. Living shorelines showed no significant differences in diversity indices but did experience similar seasonal fluctuations in diversity across treatments. Just as with oyster reefs, restored and control living shorelines harbored significantly different communities across time. The findings of this study emphasize the need for dedication to thorough monitoring and multi-metric evaluation of success in restoration efforts. This study and future research will equip resource managers with ways to quantify the effects of restoration that will consider several important ecosystem components.
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Date Issued
2019
Identifier
CFH2000545, ucf:45646
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH2000545
Business in the Estuary, Party in the Sea: Migration Patterns of Striped Mullet (Mugil cephalus) Within the Indian River Lagoon Complex
Title
Business in the Estuary, Party in the Sea: Migration Patterns of Striped Mullet (Mugil cephalus) Within the Indian River Lagoon Complex.
Creator
Myers, Olivia, Cook, Geoffrey, Mansfield, Kate, Reyier, Eric, University of Central Florida
Abstract / Description
Commercial and recreational environmental enterprises in the Indian River Lagoon (IRL), Florida supply nearly 10,000 jobs and produce $1.6 billion dollars a year in revenue. These waters contain iconic species of sportfish, including red drum, snook, and sea trout, as well as their lower trophic level prey such as snapper and mullet. Striped mullet (Mugil cephalus) are both commercially valuable as well as an indicator species for overall ecosystem health. From September to December, mullet...
Show moreCommercial and recreational environmental enterprises in the Indian River Lagoon (IRL), Florida supply nearly 10,000 jobs and produce $1.6 billion dollars a year in revenue. These waters contain iconic species of sportfish, including red drum, snook, and sea trout, as well as their lower trophic level prey such as snapper and mullet. Striped mullet (Mugil cephalus) are both commercially valuable as well as an indicator species for overall ecosystem health. From September to December, mullet in the IRL undergo an annual migration from their inshore foraging habitats to oceanic spawning sites. However, their actual migratory pathways remain unknown. To address this knowledge gap, I utilized passive acoustic telemetry to assess the migration patterns of M. cephalus within the IRL complex, particularly focusing on movement pathways from inshore aggregation sites to oceanic inlets to spawn. Coupling environmental metrics with movement data, I evaluated catalysts for migration as well as travel routes through the estuary. Network analyses identified potential conservation areas of interest and sites needing management intervention. Impoundments around the Merritt Island National Wildlife Refuge appear to serve as an important refuge area for striped mullet while the Banana and Indian Rivers act as corridors during their inshore migratory movements. The environmental metrics of depth, temperature, dissolved oxygen, pH, barometric pressure, and photoperiod were the best predictors for the number of detections and residency time produced by two case studies of striped mullet activity. An emphasis on spatial fisheries management along with vigilant environmental monitoring will ensure the status of this species, to the benefit of both natural and human systems in the Indian River Lagoon. The knowledge generated as a result of this project may also provide a framework for sustainably managing other migratory baitfish.
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Date Issued
2019
Identifier
CFE0007895, ucf:52768
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007895
Exploring multi-scale variation of fish community diversity in a dynamic coastal estuary
Title
Exploring multi-scale variation of fish community diversity in a dynamic coastal estuary.
Creator
Troast, Brittany, Cook, Geoffrey, Walters, Linda, Paperno, Richard, University of Central Florida
Abstract / Description
Examining diversity over multiple spatial and temporal scales affords the opportunity to develop a mechanistic understanding of the factors influencing community diversity dynamics, and how these may shift in a changing world. This thesis first examines multi-decadal fish community diversity metrics across a coastal biogeographic transition zone to quantify changes in species assemblages, assess relationships between fish community diversity and the abiotic environment, and capture potential...
Show moreExamining diversity over multiple spatial and temporal scales affords the opportunity to develop a mechanistic understanding of the factors influencing community diversity dynamics, and how these may shift in a changing world. This thesis first examines multi-decadal fish community diversity metrics across a coastal biogeographic transition zone to quantify changes in species assemblages, assess relationships between fish community diversity and the abiotic environment, and capture potential shifts in the location of a putative biogeographic break. Results of this chapter indicate not only a change in fish community composition, but also a shift in the location of the biogeographic transition zone. If these trends continue, a potential 16-62km shift northward by the year 2100 could occur. Understanding the novel species assemblages these shifts could result in is necessary for the future management of this area. Next this thesis examines diversity on a local scale, assessing the response of the fish community to restoration of oyster reefs and coastal wetlands which act as essential fish habitat. Results support the idea that fish community composition at restored oyster reefs is more similar to those of live reefs than dead reefs, however, results of abundance and diversity analyses were equivocal. Living shoreline analyses produced no differences between control and restored sites before or after restoration. Possible explanations for lack of clear trends in the fish community could be explained by the presence of other essential fish habitats in the area, scale of restoration, and length of monitoring. This thesis explores diversity on a multitude of spatial and temporal scales to better understand how fish communities respond to change and generates fundamental knowledge that can improve our ability to conserve and manage coastal communities and better inform the development of ecosystem-based management strategies.
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Date Issued
2019
Identifier
CFE0007905, ucf:52753
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007905
Environmental correlates of sensory sampling rate in the electrosensory system of Neotropical electric fishes
Title
Environmental correlates of sensory sampling rate in the electrosensory system of Neotropical electric fishes.
Creator
Correa Roldan, Ericka, Crampton, William, Cook, Geoffrey, Correa, Sandra, University of Central Florida
Abstract / Description
The nocturnally-active freshwater Neotropical gymnotiform electric fish generate weak electric organ discharges (EODs) that are detected by electroreceptors to facilitate active electroreception (object detection and communication - including species recognition). The EOD rate of 'pulse-type' species varies among individuals as a function of activity rate and during sexual or agonistic interactions. The extent to which EOD rate varies between and within species in natural conditions, and the...
Show moreThe nocturnally-active freshwater Neotropical gymnotiform electric fish generate weak electric organ discharges (EODs) that are detected by electroreceptors to facilitate active electroreception (object detection and communication - including species recognition). The EOD rate of 'pulse-type' species varies among individuals as a function of activity rate and during sexual or agonistic interactions. The extent to which EOD rate varies between and within species in natural conditions, and the ecological and evolutionary factors that influence such variation are poorly known. EOD rate is presumed to represent a measure of sensory sampling rate, and therefore we hypothesized that water flow velocity may correlate positively to EOD rate variation (both between and within species). To test this hypothesis, we made nocturnal EOD-rate recordings of 862 non-breeding individuals of nine common species in rainforest streams of the upper Amazon. These recordings were accompanied by measurements of additional parameters hypothesized to influence intraspecific (but not interspecific) variation in pulse rate by influencing activity rate. These parameters included conductivity and turbidity (proxies for recent rainfall), temperature and dissolved oxygen (a possible metabolic constraint on signaling), body size (representing ontogeny), and moonlight intensity (a metric of predation risk). Using multiple regression in the form of linear mixed effect models, and model selection, we determined that none of these variables explain interspecific variation in EOD rate (-) suggesting that other factors such as species recognition or non-adaptive drift represent more important ultimate drivers of interspecific variation in pulse rate. However, at the intraspecific level, we reported a substantial reduction in mean pulse rate on nights with strong moonlight in two species, Brachyhypopomus sullivani and Gymnorhamphichthys rondoni. In two other species, Brachyhypopomus beebei and Brachyhypopomus verdii, we reported elevated pulse rate during periods of increased conductivity and/or turbidity that followed rainfall and consequent flooding of ephemeral swamps adjacent to terra-firme streams.
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Date Issued
2019
Identifier
CFE0007618, ucf:52525
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007618
Go with the flow: patterns of connectivity in low dispersal coral reef gobies (Coryphopterus spp.) throughout the western Atlantic
Title
Go with the flow: patterns of connectivity in low dispersal coral reef gobies (Coryphopterus spp.) throughout the western Atlantic.
Creator
Volk, Daniel, Hoffman, Eric, Ferreira, Carlos, Cook, Geoffrey, University of Central Florida
Abstract / Description
Gene flow is an integral biological process that can mediate speciation. While many consider the ocean to be an open environment, there are many barriers that limit gene flow, particularly in the western Atlantic. I analyzed data from two widespread, coral reef fishes, the bridled goby (Coryphopterus glaucofraenum) and sand-canyon goby (C. venezuelae), throughout their range in the western Atlantic. Using two genetic datasets, mitochondrial DNA (mtDNA) and genomic SNPs, I investigated the...
Show moreGene flow is an integral biological process that can mediate speciation. While many consider the ocean to be an open environment, there are many barriers that limit gene flow, particularly in the western Atlantic. I analyzed data from two widespread, coral reef fishes, the bridled goby (Coryphopterus glaucofraenum) and sand-canyon goby (C. venezuelae), throughout their range in the western Atlantic. Using two genetic datasets, mitochondrial DNA (mtDNA) and genomic SNPs, I investigated the evolutionary history of these species and inferred the location and strength of putative barriers. My results suggest that several unique lineages have genetically diverged from one another in the presence of two major barriers. First, the Amazon River has isolated Brazil from the Caribbean and second, a unique lineage was found at an isolated oceanic island, Atol das Rocas, off the northeast coast of Brazil. Furthermore, minor barriers have caused slight genetic differentiation in each of the Caribbean species off the coast of Venezuela, while on the Brazilian coast, there are up to two barriers that separate three genetically unique areas. The stronger of the two barriers is located at Cabo Frio near an upwelling system and the weaker barrier coincides with the outflow of the S(&)#227;o Francisco River. Overall, this research highlights how barriers impact speciation and genetic structure within these gobies in the western Atlantic and more broadly, deepens our understanding about the role of oceanographic features in the speciation process.
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Date Issued
2017
Identifier
CFE0006924, ucf:51690
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006924