Pamela J Schofield, Ph.D.
Science and Products
Fish Chat and Slam November 2019
Fifty fish biologists from 15 organizations participated in a three-day Fish Chat and Slam event in South Florida on November 5-7, 2019.
Treasure Coast and Central Florida Fish Slams- 2019
In March and June 2019, USGS researchers joined partners in Treasure Coast and Central Florida where they sampled freshwater bodies for non-native fishes. The bi-annual Fish Slam event helps monitor new introductions and document range expansion of known non-native fishes.
Fish Slam November 2018
In November 2018, USGS researchers joined partners in South Florida where they sampled freshwater bodies for non-native fishes. The bi-annual Fish Slam event helps monitor new introductions and document range expansion of known non-native fishes.
Effects of Native and Non-native Fishes on Native Apple Snail Population Dynamics
The Florida apple snail is a critical component of the state's wetland food webs. USGS scientists assess the effects of native and non-native fishes on the native snail populations.
Development of a Quantitative Risk Assessment Tool to Predict Invasiveness of Non-native Freshwater Fishes in Everglades National Park
The introduction of non-native fishes is a problem across the United States, particularly in Florida. USGS scientists are developing a decision support tool to help natural resourece managers prioritize which species to focus prevention, detection, rapid response, and control efforts.
Fish Slam - November 2017
The Hunt For The Southernmost Snakehead. Thirty-one fishery biologists from eleven agencies participated in a two-day Fish Slam event. Thirty-five sites in Broward and Miami-Dade counties were sampled for non-native fishes.
Spring Fish Slam 2017 – Big Cypress
22-23 March 2017 - Ten teams of fishery biologists sampled 28 sites amid unexpected wildfires in the Big Cypress National Preserve over the two day period. On the second day a reporter from the Miami Herald accompanied a ground crew team.
Florida Non-Native Fish Action Alliance
The Florida Non-Native Fish Action Alliance brings together federal and state agencies, academic institutions, and non-governmental organizations to address the need for documenting and managing the non-native fishes introduced to the state's waters.
Fish Slam - Fall 2016
November 1 - 2, 2016 – Eight teams of fishery biologists from the US Geological Survey (USGS), US Fish and Wildlife Service - Peninsular Florida Fisheries Office and Welaka National Fish Hatchery (USFWS), the National Park Service (NPS), Florida Fish and Wildlife Conservation Commission (FWC), Florida International University (FIU), and Zoo Miami sampled 20 sites for non-native fishes in Palm...
Fish Slam - Spring 2016
May 23, 2016 – Five teams of fishery biologists from the U.S. Geological Survey (USGS), Florida Fish and Wildlife Conservation Commission (FWC), the National Park Service (NPS), Florida Museum of Natural History (FLMNH), University of Florida (UF), and Florida International University (FIU) sampled 12 sites for non-native fishes in Broward and Miami-Dade counties in southeastern Florida.
Detection, tracking, and removal of non-native marine fishes in Florida
Thirty-four species of non-native marine fishes have been documented in Florida, and their distributions are currently being tracked via the US Geological Survey’s Nonindigenous Aquatic Species (USGS-NAS) database.
Lionfish Distribution, Geographic Spread, Biology, and Ecology
Many aspects of lionfish biology are studied at the USGS Wetland and Aquatic Research Center. As part of the U.S. Geological Survey Nonindigenous Aquatic Species database, the distribution of lionfish is tracked over time.
Expert bioblitzes facilitate non-native fish tracking and interagency partnerships
Documenting the distribution and composition of non-native species populations can be challenging, especially when species cross jurisdictional boundaries that require interagency coordination. Herein I report the development of three tools that have been used in Florida over the past seven years to assist with tracking of non-native fishes: 1) an...
Schofield, Pamela J.A comparison of the Trojan Y Chromosome strategy to harvesting models for eradication of nonnative species
The Trojan Y Chromosome strategy (TYC) is a promising eradication method for biological control of nonnative species. The strategy works by manipulating the sex ratio of a population through the introduction of supermales that guarantee male offspring. In the current study, we compare the TYC method with a pure harvesting strategy. We...
Lyu, Jingjing; Schofield, Pamela J.; Reaver, Kristen; Beauregard, Matthew; Parshad, Rana D.Genetic Characterization of Non-Native African Jewelfish, Hemichromis letourneuxi Sauvage 1880, in Florida
The African Jewelfish, Hemichromis letourneuxi, is an invasive, predatory cichlid fish introduced at least once to Florida. Its native range is in northern Africa. First encountered in Miami in the 1960s, it has since been found west and north within the State of Florida. It thrives in a wide range of aquatic habitats, including shallow,...
Belfiore, Natalia M.; Schofield, Pamela J.Environmental DNA (eDNA) detection of nonnative bullseye snakehead in southern Florida
Bullseye Snakehead Channa marulius (Hamilton 1822) was first detected in the southern Florida town of Tamarac in 2000 and has been expanding its geographic range since. Environmental DNA (eDNA) analysis is a newly-developed technique used to noninvasively detect cryptic or low-density species or those that are logistically difficult-to-study....
Hunter, Margaret; Schofield, Pam; Meigs-Friend, Gaia; Brown, Mary; Ferrante, JasonNon-native marine fishes in Florida: Updated checklist, population status and early detection/rapid response
It has been ten years since the last comprehensive assessment of non-native marine fishes in Florida. Herein, we report sightings of 41 species from Florida coastal waters since the earliest reported sighting in 1984. Information is provided on the population status of each species (e.g., established, eradicated, unknown), and our early detection/...
Schofield, Pamela J.; Akins, LadEradication of two non-native cichlid fishes in Miami, Florida (USA)
The proliferation of non-native fishes in Florida is a serious problem, and new species continue to be introduced to the state. Fishes in the Family Cichlidae have been especially successful colonizers of south Florida freshwater habitats. Herein we report a multi-agency effort to eradicate two non-native cichlid fishes in Miami, Florida (Bay...
Schofield, Pamela J.; Jelks, Howard L.; Gestring, Kelly B.Introduction and dispersal of non-native bullseye snakehead Channa marulius (Hamilton, 1822) in the canal system of southeastern Florida, USA
An established population of bullseye snakehead (Channa marulius), a large predatory fish from southeastern Asia, was identified for the first time in North America from waters in southeastern Florida, USA, in the year 2000. Since then, it has dispersed throughout the extensive canal system in the area from West Palm Beach south to Miramar....
Benson, Amy J.; Schofield, Pamela J.; Gestring, Kelly B.Salinity tolerance among three freshwater mussels (Bivalvia: Unionidae) from Gulf Coastal Plain drainages
An important physiological constraint influencing distributions of coastal freshwater organisms is their tolerance for saline conditions. We experimentally evaluated salinity tolerance for three freshwater mussel species (Utterbackia imbecillis, Elliptio jayensis, and Glebula rotundata). Mussels were transferred abruptly from well water to one of...
Johnson, Nathan A.; Schofield, Pamela J.; Williams, James D.; Austin, James D.Lower lethal temperatures for nonnative freshwater fishes in Everglades National Park, Florida
Temperature is an important factor that shapes biogeography and species composition. In southern Florida, the tolerance of nonnative freshwater fishes to low temperatures is a critical factor in delineating their geographic spread. In this study, we provide empirical information on experimentally derived low-temperature tolerance limits of Banded...
Schofield, Pamela J.; Kline, Jeffrey L.Non-native fishes of the central Indian River Lagoon
We provide a comprehensive review of the status of non-native fishes in the central Indian River Lagoon (from Cape Canaveral to Grant-Valkaria, east of I-95) through literature review and field surveys. Historical records exist for 17 taxa (15 species, one hybrid, one species complex). We found historical records for one additional species, and...
Schofield, Pamela J.; Loftus, William F.; Reaver, Kristen M.Salinity tolerance of non-native suckermouth armoured catfish (Loricariidae: Pterygoplichthys sp.) from Kerala, India
Loricariid catfishes of the genus Pterygoplichthys are native to South America and have been introduced in many localities around the world. They are freshwater fishes, but may also use low-salinity habitats such as estuaries for feeding or dispersal. Here we report results of a field survey and salinity-tolerance experiments for a population of...
Kumar, A. Biju; Schofield, Pamela J.; Raj, Smrithy; Satheesh, SimaOsmoregulation and muscle water control in vitro facing salinity stress of the Amazon fish Oscar Astronotus ocellatus (Cichlidae)
Specimens of Oscar Astronotus ocellatus from a fish farm were abruptly submitted to salt stress of 14 ppt and 20 ppt, for 3 and 8 h to determine their plasma osmolality. Muscle wet body mass change in vitro was analyzed from control freshwater animals. Fish in 14 ppt presented no osmolality distress even after 8 h. In...
Gutierre, Silvia M. M.; Schulte, Jessica M.; Schofield, Pamela J.; Prodocimo, VivianePre-USGS Publications
USGS and Partners Team Up to Track Down Nonnative and Invasive Fishes in South Florida
The Fish Slam event discovered two nonnative fish species never seen before in Big Cypress National Preserve.
Blotched Foxface Fish Found in Florida Waters
Fish Marks 36th Non-Native Marine Fish Species Found in State
Taming the Lion(fish)
Genetics and tracking helps USGS researchers learn where the invasive fish are now – and where they may go next.