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Differences in Secondary Consumer Behavioral Responses to Predators on Natural and Artificial Reefs in South Florida
No full textOn coral reefs, intensifying local stressors and climate change reconfigure reef ecosystems, with largely unknown implications for critical ecosystem functions (i.e., predation and secondary consumers). The study investigated differences in fish assemblages on natural and artificial reefs and how predator presence affected secondary consumer (i.e. invertivorous fish) abundance and foraging behaviors on natural versus artificial reefs. The specific objectives of this study were: (i) determine whether secondary consumer abundances differ between artificial and natural reefs and (ii) assess how predator identity influences the foraging behavior of secondary consumers. The study was conducted on shallow natural and artificial reefs in Broward County. Point count surveys measured species abundance and species communities. Standardized assays using dried squid, (i.e., “squidpops) in conjunction with predator treatments, measured fear effects through underwater video surveillance. Secondary consumer responses were quantified to threat treatments: a black grouper (Mycteroperca bonaci) model, a great barracuda (Sphyraena barracuda) model, an object control, and a control. We found significantly greater fish abundances and differing species communities on natural reefs than on artificial reefs. Fish reduced foraging differences between natural and artificial reefs, potentially due to encounter rates; however, the exact mechanism driving this pattern remains unknown. Fish perceive a difference between predator treatments, with more perceived risk to the grouper model, suggesting predator identity impacts secondary consumer foraging. In conservation, enhancing structural complexity in artificial reefs can support diverse fish communities and natural predator-prey interactions. Future research should explore habitat features that optimize foraging and defense, boosting fish resilience and the marine ecosystem
Keynote: Master of the House? Emerging Insights on the Cell Biology and Ecology of Coral-Dinoflagellate Mutualisms
No full textCertain kinds of invertebrates engage with unicellular dinoflagellates to form complex, highly integrated, mutualisms. While eukaryotes as symbionts are extremely rare among notable Intracellular mutualisms, this special union is exceptionally widespread and their productivity results in the creation of a major tropical marine ecosystem. Sensitivity to thermal stress and the demise of coral reef ecosystems globally has stirred considerable interest in the cell biology, physiology, and ecology of this partnership. The recent critical advances in resolving the symbiont’s identity have changed our understanding of these mutualisms in fundamental ways. The testing of various species concepts and establishment of a formal systematics and taxonomy has shifted perceptions about symbiont diversity, distribution, host specificity, and evolution. These basic innovations, made possible with the use of genetics, have lead to exciting discoveries and created new areas of inquiry. Sampling diverse host species living across geographic and depth gradients and the same host individual over time, combined with experimental manipulations of host colonies have provided additional insights about the ecological habits and evolutionary dynamics of the dinoflagellate partner. This and related research reveals much about the give and take of these mutualisms and which partner has greater control over the relationship
Answers in a Drop of Water: eDNA and its Application in Marine and Freshwater Conservation
No full textEnvironmental DNA (eDNA) analyses have become a widely used technique allowing rapid biodiversity screening and monitoring. DNA from every organism is released from body fluids or the skin into its environment and remains there for a limited time. This talk will present a summary of different eDNA applications to investigate research questions related to biological community composition and its change over time, as well as to detect specific species to further understand their distribution patterns and conservation needs. We will present results for a variety of ecosystems, from freshwater habitats in the Amazon, Orinoco and Magdalena rivers as well as cave ecosystems in Colombia, to tropical marine ecosystems in the Colombian Pacific, as well as research in the Western Antarctic Peninsula. The talk will also focus on how to involve members from local communities and tourist in eDNA sample collection and the use of results in education and recovery of ancestral knowledge
Experimental Core Healing in Orbicella faveolata as an Indicator of Colony Health
No full textNatural and anthropogenic coral wounding has been shown to detract from a common resource pool, increasing disease susceptibility and impairing coral growth and reproductive activity. Regeneration not only varies between species, but also between conspecifics in the same location. A colony’s capacity to regenerate tissue can be an indicator of a colony’s condition and resilience. Understanding the physiological and environmental factors that affect tissue regeneration alongside the ultimate impact of sampling (disease and predation correlations) are needed for this to be a useful indicator. This research analyzed the tissue regenerative rates of core lesions on eighty-seven colonies (45 in SE FL and 42 in the lower FL Keys) of the reef-building species Orbicella faveolata sampled over three time periods corresponding to different environmental conditions and stages of the metabolically taxing state of gametogenesis (1,717 cores total). Monthly standardized pictures of each core site were measured to calculate tissue regeneration rates for each colony and to assess the long-term effect of core sampling. Results found that regeneration rate differed by region and between colonies, with highest rates seen in the Kristin Jacobs Coral Ecosystem Conservation Area compared to Keys sites with increasing growth rates with latitude. Disease history before and throughout the study, genetic lineage, and predation were not found to be significant in predicting regeneration rate. Predation was most prevalent in the early summer sample period, likely because cores were left unfilled with ablative clay. Predation and disease outcomes were low throughout the study despite high endemic SCTLD levels and parrotfish populations. Lastly, most colonies were in a state of repair with 25% of biopsied tissue regrown by the end of the study. This study adds a valuable metric in the diagnosis and tracking of Orbicella faveolata condition over temporal and spatial scales uncommon in this field
Genomic Assessment of Ancestry and Natural History in a Captive Tiger Living in New York City Projects
No full textThe world’s free-ranging tiger population, found exclusively in Asia, has dwindled from over 100,000 individuals at the beginning of the 19th century to around 4000 living in the wild today. However the popularity of the species has spawned a sizable captive population of over 12,000 tigers of uncertain ancestry and natural history.
Whole genome sequence-WGS of wild tigers revealed a substantive distinctiveness among six living tiger subspecies allowing for reliable molecular recognition of subspecies. A forensic case involving a pet tiger, named Ming, illegally kept in a housing project in Harlem is reviewed here. Subspecies ancestry of Ming was determined by comparing his WGS (derived from trace DNA from plucked whiskers) to SNP annotation from thee WGS of 35 voucher (pure subspecies) tiger specimens from six living subspecies. Genome-wide structure analyses based on 3,422,109 SNPs and a subset of 6,724 Ancestry-Informative Markers (AIMS) showed that Ming his sister Cheeky had an admixed genetic background from five subspecies: Indochinese tiger (Panthera tigris corbetti 35 ~ 40%), Bengal tiger (P. t. tigris 17 ~ 23%), Sumatran tiger (P. t. sumatrae 12 ~ 14%), Amur tiger (P. t. altaica ~ 10%), and Malayan tiger (P. t. jacksoni 1 ~ 10%).
The tale of Ming and Cheeky (published inn Journal of Heredity Jan 28, 2025 - https://doi.org/10.1093/jhered/esaf003) is a chronicle around a critically endangered species that has suffered from illegal trafficking in a lucrative pet trade at a cost of individual animal cruelty
Octocoral Microbiome: Towards an Understanding of Octocoral-Bacteria Interactions on Florida’s Coral Reefs
No full textBacterial communities in coral holobionts play essential roles in supporting host health and resilience. While scleractinian coral populations on Florida reefs have been devastated by marine heatwaves, disease, and other stressors, octocorals have demonstrated notable resilience and now dominate many sites. Despite this ecological significance, the octocoral microbiome remains largely understudied, with most insights extrapolated from scleractinian research. This gap limits our understanding of how bacterial assemblages contribute to octocoral resilience. This study investigates the composition and community structure of octocoral-associated bacteria across four species: Briareum asbestinum, Eunicea flexuosa, Erythropodium caribaeorum, and Muricea muricata. Samples were collected from southeast Florida during the summers of 2023 and 2024 and analyzed using 16S rRNA amplicon profiling. Our initial results reveal significant species-specific diversity, contributing to substantial differences among species. In addition, we show that growth form greatly influences differences between octocoral bacterial assemblages. Additionally, to better understand the response of the octocoral microbiome to stress conditions, colonies of Briareum asbestinum were experimentally exposed to local strain of Vibrio spp., and their microbiomes were compared with a control group. Taken together, this approach aims to catalog dominant and rare bacterial taxa associated with octocorals across varying conditions and examine microbial responses to stress. The study results can establish a baseline of bacterial communities in healthy octocoral colonies and species, shedding light on microbial contributions to the resilience of these corals in rapidly changing environments
Various -omics Tools Reveal the Versatility of Cyanobacterial Bloom Formers in the Lake Okeechobee Watershed
No full textOur laboratory has studied cyanobacterial harmful algal blooms (cyanoHABs) in nearby Lake Okeechobee (LO) watershed. Because of multiple negative environmental and human health impacts, we have now characterized potential bloom drivers and successional stages. Our research has applied an integrative approach to: (a) assess biodiversity and phylogeny of cyanobacteria and associated microorganisms (i.e. cyanobacteria-microbiota) in various phases of bloom events, and (b) investigate the genetic basis and functional roles of cyanobacteria-heterotrophic microbial diversity along a spatiotemporal gradient. Using monthly Lake O sampling for 3 years and a variety of “-omics” methods such as 16S rRNA amplicon sequencing, metagenomics and metatranscriptomic methods, we have developed a better understanding of microbial community dynamics. During one bloom season (2019-2020), over 70 metagenomically assembled genomes (MAGs) helped corroborate Lake O biogeographical zones with distinct microbial community composition and functions. Identification of novel cyanoHABs and changes in relative abundances of taxa within multiple bacteria tracked bloom severities. Functional pathways that correlated with increasing bloom severity encoded organic nitrogen and phosphorus utilization, storage of nutrients, exchange of genetic material, phage defense, and protection against oxidative stress, suggesting that microbial interactions may promote cyanoHABs resilience. Cyanobacterial communities appeared highly diverse, with ubiquitous picocyanobacteria. Genomic comparisons indicated a functionally diverse cyanobacterial community with varying capabilities to store nitrogen via cyanophycin and phage defenses with CRISPR and restriction modification systems. In situ mesocosm experiments on the Caloosahatchee River (Southwest Florida, USA), tested the effects of artificial loading of nutrients (phosphorus, nitrate, ammonia and urea) on pelagic microbiomes. Metatranscriptomes characterized the community response associated with upon treatment with ammonium and urea for 72 hours, primarily inducing photosynthesis and both phosphate and carbon transport and metabolism. Urea addition also induced upregulation of carbon storage, amino acid metabolism, microcystin biosynthesis, and other processes associated with cell growth and appeared to intensify a concomitant Microcystis bloom in 2021
Caribbean Gorgonian Coral-Zooxanthellae Network: Establishing Critical Symbiotic Relationships in an Uncertain Climate
No full textRising oceanic temperatures have placed Caribbean organisms under immense heat stress and restructured its reefs such that gorgonians (along with sponges) are now predominant organisms. Caribbean gorgonians are partially heterotrophic but also depend on their symbiotic photosynthetic zooxanthellae to survive. Gorgonian species and their associated algae provide habitat for reef fish and invertebrates and aid in nutrient cycling throughout the water column. Our understanding of the robustness of their symbiotic relationships relies primarily on assessments of individuals within a few species, rather than species and systems level knowledge. For this reason, we set out to create a symbiosis network of Caribbean gorgonians and the Symbiodiniaceae that inhabit them. This included compiling Caribbean gorgonian species and genetic identification of symbiont ITS2 phylotypes to establish host-symbiont specificity for 23 out of 63 known species of Caribbean gorgonian. It revealed that the overwhelming majority of species host Symbiodiniaceae of the genus Breviolum. Connectivity metrics demonstrate low connectivity between host species, but the network is not complete enough to draw reputable conclusions. These symbiosis networks highlight multiple avenues of future research to better understand the systems biology of Caribbean gorgonians
Geriatrics in a Multicultural Society
No full texthttps://nsuworks.nova.edu/gwep_modules/1002/thumbnail.jp