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Margaret Hunter, Ph.D.
Ph.D., Veterinary Medical Sciences, University of Florida
B.S., Microbiology and Cell Sciences (Minor: Chemistry, Plant Molecular and Cellular Biology), University of Florida
Margaret Hunter attended the University of Florida where she received a B.Sc. in Microbiology and Cellular Sciences and minored in Chemistry and Plant Molecular and Cellular Biology. Following her bachelor degree, she received a PhD in Veterinary Medical Sciences researching Sirenia (manatee and dugong) cytogenetics and conservation genetics. Affiliations: USGS Sirenia Project USGS Genetics and Genomics Research Courtesy Assistant Professor, University of Florida, College of Veterinary Medicine, Department of Large Animal Clinical Sciences Affiliated faculty member, University of Florida Aquatic Animal Health Program Affiliated faculty member, University of Florida Genetics Institute.
Science and Products
Nuclear microsatellite markers have been developed and implemented on ~2,000 West Indian manatees. These markers provide individual genetic fingerprints for mark-recapture studies, population structure information for the conservation of unique or isolated populations, and pedigree and relatedness information for addressing inbreeding and breeding structure patterns.
Statistical Models for the Design and Analysis of Environmental DNA (eDNA) Surveys of Invasive and Imperiled Species
Detecting invasive species at low densities or prior to population establishment is critical for successful control and eradication. For example, Burmese pythons occupy thousands of square kilometers of mostly inaccessible habitats.
To control or possibly eliminate non-native species without harm to native fauna, a genetic technique using sex-reversed females with two Y chromosomes (Trojan Y) is being developed to reduce the breeding success of the species, ultimately resulting in population decline or loss.
The Asian tiger shrimp began appearing in commercial shrimp catches in 2006. They grow larger than native shrimp and are known to be fierce predators - so shrimpers and managers are concerned about the potential effects this species might have.
Developing Detection Probabilities and Quantifying the Effects of Flowing Water to Improve Asian Carp Environmental DNA (eDNA) Surveys
Invasive Asian carp are problematic for native species, and managers are implementing control measures without well-quantified detection limits or a means to assess the accuracy and precision of existing or future survey data for the fish. Environmental DNA - eDNA - is already used to detect the presence of invasive species, and can be used to identify locations to focus carp control efforts...
Efficacy of eDNA as an Early Detection and Rapid Response Indicator for Burmese Pythons in the Northern Greater Everglades Ecosystem
Traditional approaches to locating Burmese pythons - including visual searches and trapping - have resulted in low detection. Environmental DNA - or eDNA - is increasingly being used to detect the presence of non-native species, particularly when traditional methods may not be adequate.
Genetic Analysis of the Invasive Burmese Python to Aid Management and Population-Control Decision-Making
Invasive Burmese pythons threaten the success of Everglades restoration efforts. To assist with management and population control decision making, USGS scientists are implementing genetic studies to identify potential new entry pathways and to help quantify the size of the breeding population.
Black carp have likely been present in the Mississippi River since the 1990s, but their current distribution and spread is not well understood. Genetics is helping to shed light on this species, including its diversity, the relatedness of wild and captive fish, and its introduction history.
Using Environmental DNA for Burmese Python Detection Probabilities and Range-Delimitation in Southern Florida
Current tools for detection of Burmese pythons in South Florida have resulted in low detection rates. Environmental DNA - eDNA - has shown to be effective at detecting these invasive snakes, and can help to determine range limits for the species, information that is critical for management and control efforts.
Genetic composition and connectivity of the Antillean manatee (Trichechus manatus manatus) in Panama
Genetic diversity and haplotype composition of the West Indian manatee (Trichechus manatus) population from the San San Pond Sak wetland in Bocas del Toro, Panama was studied using a segment of mitochondrial DNA (D’loop). No genetic information has been published to date for Panamanian populations. Due to the secretive behavior and small...Díaz-Ferguson, Edgardo; Hunter, Margaret; Guzmán, Héctor M.
Detection limits of quantitative and digital PCR assays and their influence in presence-absence surveys of environmental DNA
A set of universal guidelines is needed to determine the limit of detection (LOD) in PCR-based analyses of low concentration DNA. In particular, environmental DNA (eDNA) studies require sensitive and reliable methods to detect rare and cryptic species through shed genetic material in environmental samples. Current strategies for assessing...Hunter, Margaret; Dorazio, Robert M.; Butterfield, John S.; Meigs-Friend, Gaia; Nico, Leo; Ferrante, Jason A.
Statistical models for the analysis and design of digital polymerase chain (dPCR) experiments
Statistical methods for the analysis and design of experiments using digital PCR (dPCR) have received only limited attention and have been misused in many instances. To address this issue and to provide a more general approach to the analysis of dPCR data, we describe a class of statistical models for the analysis and design of experiments that...Dorazio, Robert; Hunter, Margaret
Habitat use patterns of the invasive red lionfish Pterois volitans: a comparison between mangrove and reef systems in San Salvador, Bahamas
The Indo-Pacific red lionfish Pterois volitans is widespread both in its native and its non-native habitats. The rapid invasion of this top predator has had a marked negative effect on fish populations in the Western Atlantic and the Caribbean. It is now well documented that lionfish are invading many tropical and sub-tropical habitats....Pimiento, Catalina; Nifong, James C.; Hunter, Margaret E.; Monaco, Eric; Silliman, Brian R.
Environmental DNA (eDNA) sampling improves occurrence and detection estimates of invasive Burmese pythons
Environmental DNA (eDNA) methods are used to detect DNA that is shed into the aquatic environment by cryptic or low density species. Applied in eDNA studies, occupancy models can be used to estimate occurrence and detection probabilities and thereby account for imperfect detection. However, occupancy terminology has been applied inconsistently in...Hunter, Margaret E.; Oyler-McCance, Sara J.; Dorazio, Robert M.; Fike, Jennifer A.; Smith, Brian J.; Hunter, Charles T.; Reed, Robert N.; Hart, Kristen M.
Marsh rabbit mortalities tie pythons to the precipitous decline of mammals in the Everglades
To address the ongoing debate over the impact of invasive species on native terrestrial wildlife, we conducted a large-scale experiment to test the hypothesis that invasive Burmese pythons (Python molurus bivittatus) were a cause of the precipitous decline of mammals in Everglades National Park (ENP). Evidence linking pythons to mammal declines...McCleery, Robert A.; Sovie, Adia; Reed, Robert N.; Cunningham, Mark W.; Hunter, Margaret E.; Hart, Kristen M.
Wide-ranging phylogeographic structure of invasive red lionfish in the Western Atlantic and Greater Caribbean
The red lionfish (Pterois volitans) is an invasive predatory marine fish that has rapidly expanded its presence in the Western Hemisphere. We collected 214 invasive red lionfish samples from nine countries and territories, including seven unpublished locations. To more comprehensively evaluate connectivity, we compiled our d-loop sequence ...Butterfield, John S.; Díaz-Ferguson, Edgardo; Silliman, Brian R.; Saunders, Jonathan W.; Buddo, Dayne; Mignucci-Giannoni, Antonio A.; Searle, Linda; Allen, Aarin Conrad; Hunter, Margaret E.
Convergent evolution of the genomes of marine mammals
Marine mammals from different mammalian orders share several phenotypic traits adapted to the aquatic environment and therefore represent a classic example of convergent evolution. To investigate convergent evolution at the genomic level, we sequenced and performed de novo assembly of the genomes of three species of marine mammals (the killer...Foote, Andrew D.; Liu, Yue; Thomas, Gregg W.C.; Vinař, Tomáš; Alföldi, Jessica; Deng, Jixin; Dugan, Shannon; van Elk, Cornelis E.; Hunter, Margaret; Joshi, Vandita; Khan, Ziad; Kovar, Christie; Lee, Sandra L.; Lindblad-Toh, Kerstin; Mancia, Annalaura; Nielsen, Rasmus; Qin, Xiang; Qu, Jiaxin; Raney, Brian J.; Vijay, Nagarjun; Wolf, Jochen B. W.; Hahn, Matthew W.; Muzny, Donna M.; Worley, Kim C.; Gilbert, M. Thomas P.; Gibbs, Richard A.
Genetic analysis of invasive Asian Black Carp (Mylopharyngodon piceus) in the Mississippi River Basin: evidence for multiple introductions
Invasive Asian Black Carp (Mylopharyngodon piceus) have been present in USA aquaculture facilities since the 1980s and wild Black Carp have been found in the Mississippi River Basin since the early 1990s. This study characterizes the genetic diversity and relatedness of the Basin’s Black Carp and clarifies the introduction history. Analyses...Hunter, Margaret E.; Nico, Leo G.
Regional differentiation among populations of the Diamondback terrapin (Malaclemys terrapin)
The Diamondback terrapin (Malaclemys terrapin) is a brackish-water turtle species whose populations have been fragmented due to anthropogenic activity such as development of coastal habitat and entrapment in commercial blue crab (Callinectes sapidus) fishing gear. Genetic analyses can improve conservation efforts for the long-term protection of...Hart, Kristen M.; Hunter, Margaret E.; King, Tim L.
Invasion of Asian tiger shrimp, Penaeus monodon Fabricius, 1798, in the western north Atlantic and Gulf of Mexico
After going unreported in the northwestern Atlantic Ocean for 18 years (1988 to 2006), the Asian tiger shrimp, Penaeus monodon, has recently reappeared in the South Atlantic Bight and, for the first time ever, in the Gulf of Mexico. Potential vectors and sources of this recent invader include: 1) discharged ballast water from its native range in...Fuller, Pam L.; Knott, David M.; Kingsley-Smith, Peter R.; Morris, James A.; Buckel, Christine A.; Hunter, Margaret E.; Hartman, Leslie D.
Role of a polymorphism in a Hox/Pax-responsive enhancer in the evolution of the vertebrate spine
Patterning of the vertebrate skeleton requires the coordinated activity of Hox genes. In particular, Hox10 proteins are essential to set the transition from thoracic to lumbar vertebrae because of their rib-repressing activity. In snakes, however, the thoracic region extends well into Hox10-expressing areas of the embryo, suggesting that these...Guerreiro, Isabel; Nunes, Andreia; Woltering, Joost M.; Casaca, Ana; Nóvoa, Ana; Vinagre, Tânia; Hunter, Margaret E.; Duboule, Denis; Mallo, Moisés
Environmental DNA picks up traces of the elusive mammals’ saliva, skin, waste, or exhaled breaths.
It may be hard to believe the legend that sailors long-at-sea once believed manatees to be mermaids. The manatee nickname the “Sea Cow” – named so for their affinity for grazing on vegetation and their slow, ambling way – just makes more sense. But a new U.S. Geological Survey video reveals that while they may be cow-like, they also have more than a bit of magical mermaid to them.