Morphological Identification of Bighead Carp, Silver Carp, and Grass Carp Eggs Using Random Forests Machine Learning Classification

In this study, we share an approach to locate and map forest management units with high accuracy and with relatively rapid turnaround. Our study area consists of private, state, and federal land holdings that cover four counties in North-Central Washington, USA (Kittitas, Okanogan, Chelan and Douglas). This area has a rich history of landscape change caused by frequent wildfires, insect attacks, disease outbreaks, and forest management practices, which is only partially documented across ownerships in an inconsistent fashion. To consistently quantify forest management activities for the entire study area, we leveraged Sentinel-2 satellite imagery, LANDFIRE existing vegetation types and disturbances, monitoring trends in burn severity fire perimeters, and Landsat 8 Burned Area products. Within our methodology, Sentinel-2 images were collected and transformed to orthogonal land cover change difference and ratio metrics using principal component analyses. In addition, the Normalized Difference Vegetation Index and the Relativized Burn Ratio index were estimated. These variables were used as predictors in Random Forests machine learning classification models. Known locations of forest treatment units were used to create samples to train the Random Forests models to estimate where changes in forest structure occurred between the years of 2016 and 2019. We visually inspected each derived polygon to manually assign one treatment class, either clearcut or thinning. Landsat 8 Burned Area products were used to derive prescribed fire units for the same period. The bulk of analyses were performed using the RMRS Raster Utility toolbar that facilitated spatial, statistical, and machine learning tools, while significantly reducing the required processing time and storage space associated with analyzing these large datasets. The results were combined with existing LANDFIRE vegetation disturbance and forest treatment data to create a 21-year dataset (1999–2019) for the study area.

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Invasive Asian Carps in North America

Invasive Asian Carps in North America ◽

10.47886/9781934874233.ch17 ◽

2011 ◽

Keyword(s):

Grass Carp ◽

Juvenile Fish ◽

Silver Carp ◽

Reproductive Potential ◽

Asian Carp ◽

Bighead Carp ◽

Ctenopharyngodon Idella ◽

Market Demand ◽

Black Carp ◽

Asian Carps

Abstract.—In the 1970s, commercial fishers reported sightings of grass carp Ctenopharyngodon idella in large rivers and associated backwaters of Louisiana; the first specimen in Louisiana Department of Wildlife and Fisheries’ fishery independent sampling was recorded in 1976. Beginning in the early 1980s, commercial fishers noted increasing populations of bighead carp Hypophthalmichthys nobilis and silver carp H. molitrix (together, the bigheaded carps). Populations of bigheaded carps appear to be increasing at a much slower rate than in the Midwest¸ possibly due to limited suitability of and access to backwater habitat for juvenile fish. In 2002, harvester reports of sporadic captures of “different-looking” grass carp indicated the possible presence of black carp Mylopharyngodon piceus. Because both normal diploid and triploid (in which triploidy has been induced to cause sterility) black carp have been stocked in the Mississippi basin, determination of the ploidy (number of chromosome sets) of these fishes is important. Since 2002, postmortem ploidy determinations using cells from eyeballs removed from six wild black carp captured in Louisiana showed each to be a normal diploid, indicative of breeding capability and potential reproducing populations. Although reported commercial landings of grass and bigheaded carps have been as high as 34,830 kg/year, limited market demand in past years resulted in many captures being discarded. A protocol for obtaining samples for easily determining ploidy is reported here. Accurate data on Asian carp distributions and their reproductive potential provides information to fisheries researchers that will be constructive in documenting the spread of these invasive species and in the assessment of risk to habitats.

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Invasive Asian Carps in North America

Invasive Asian Carps in North America ◽

10.47886/9781934874233.ch11 ◽

2011 ◽

Keyword(s):

North America ◽

Grass Carp ◽

Silver Carp ◽

Federal Agencies ◽

Bighead Carp ◽

Commercial Fish ◽

Fish And Wildlife Service ◽

In The Wild ◽

Asian Carps ◽

The U.S

Abstract.—Numerous natural resource agency and media reports have alleged that Asian carps were introduced into the wild through escapes from commercial fish farms. This chapter traces the chronology associated with importations of Asian carps to North America and discusses the likeliest pathways of their introduction to the wild. The U.S. Fish and Wildlife Service first imported an Asian carp species, grass carp Ctenopharyngodon idella, in 1963. Since then, state and federal agencies, universities, and private fish farmers have interacted to import Asian carps, to develop production technologies, and to promote their use in both public and private sectors in a number of different states. These importations and stocking, whether in confinement or, in the case of the grass carp, sometimes in open waters, were purposeful and legal. Asian carps were introduced to take advantage of their unique food preferences (planktivory by silver carp Hypophthalmichthys molitrix and bighead carp H. nobilis, herbivory by grass carp, and molluscivory by black carp Mylopharyngodon piceus). The first known accidental release of diploid grass carp was in 1966 by the U.S. Fish and Wildlife Service in Stuttgart, Arkansas. Other early reports of grass carp in the wild were from waters in Alabama, Georgia, and Florida. Grass carp were reported from the wild in 1970, 2 years before the first private hatchery received grass carp. By 1972, grass carp had been stocked in open water systems in 16 different states. Silver carp and bighead carp were first imported purposely by a commercial fish producer in Arkansas in 1973. All silver and bighead carps were transferred to the Arkansas Game and Fish Commission by March 1974 where they first successfully spawned silver carp and bighead carp later that year. The first report of silver carp in the wild was in Arizona in 1972, although strong evidence suggests that this may have been a misidentification, followed by reports in Arkansas in the wild in 1975. The Arkansas report occurred 2 years before bighead carp and silver carp were returned to private hatcheries for commercial production. By 1977, silver carp and bighead carp had been introduced to Alabama, Arizona, Arkansas, Illinois, and Tennessee. Research and stockings of silver carp and bighead carp were conducted by at least six state and federal agencies and three universities in seven states in the 1970s and 1980s. Public-sector agencies, which were successful in encouraging development and use of Asian carps that today are in commercial trade, are the likeliest pathways for the earliest escapes of grass carp, silver carp, and bighead carp.

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Genetic variability of natural populations of silver carp, bighead carp and grass carp in the Yangtze River

Aquaculture ◽

10.1016/0044-8486(93)90112-c ◽

1993 ◽

Vol 111 (1-4) ◽

pp. 327

Author(s):

Wu Lizhao ◽

Wang Zuxiong ◽

Cao Yongchang

Keyword(s):

Genetic Variability ◽

Grass Carp ◽

Yangtze River ◽

Silver Carp ◽

Natural Populations ◽

Bighead Carp ◽

The Yangtze River

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Mitochondrial DNA diversity, population structure, and conservation genetics of four native carps within the Yangtze River, China

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f96-266 ◽

1997 ◽

Vol 54 (1) ◽

pp. 47-58 ◽

Cited By ~ 20

Author(s):

G Lu ◽

S Li ◽

L Bernatchez

Keyword(s):

Mitochondrial Dna ◽

Population Structure ◽

Grass Carp ◽

Yangtze River ◽

Juvenile Fish ◽

Silver Carp ◽

Bighead Carp ◽

The Yangtze River ◽

Black Carp ◽

Dna Diversity

Silver carp (Hypophthalmichthys molitrix), grass carp (Ctenopharyngodon piceus), bighead carp (Aristichthys nobilis), and black carp(Mylopharyngodon piceus) rank first, second, fourth, and seventh in world fish production. In China, the Yangtze River harbours the most important natural populations of these species. We performed a polymerase chain reaction - restriction fragment length poymorphism analysis on 365 juvenile fish representing three nursery grounds to provide a first assessment of the mitochondrial DNA diversity in these species and test the hypothesis that they are composed of more than one genetic stock. The mitochondrial DNA diversity was high in silver, bighead, and black carp, and much less in grass carp. Analysis of heterogeneity of genotype frequency, fixation indices, intersite molecular variance, and localization indices indicated that juvenile silver, bighead, and black carp from different nursery areas belong to genetically distinct populations. These results suggest that their population structure may be determined by the number of environmental settings that permit closure of their life cycle. They also imply that carp from the Yangtze River cannot be managed as a single unit and that human disturbance through exploitation and habitat modifications, in particular the construction of the Three Gorges Dam, will have differential impacts on fish abundance for different parts of the river.

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Features of the parasitic system formation in herbivorous fish in the aquaculture of the North-Eastern and Eastern regions of Ukraine

Journal for Veterinary Medicine, Biotechnology and Biosafety ◽

10.36016/jvmbbs-2020-6-1-4 ◽

2020 ◽

Vol 6 (1) ◽

pp. 18-24

Author(s):

A. V. Yevtushenko

Keyword(s):

Grass Carp ◽

Silver Carp ◽

Bighead Carp ◽

Herbivorous Fish ◽

The North ◽

North Eastern ◽

Parasitic System ◽

Bothriocephalus Acheilognathi ◽

High Level ◽

Lernaea Cyprinacea

The research aimed to determine the peculiarities of the formation of the parasitic system in herbivorous fish in the aquaculture of the North-Eastern and Eastern regions of Ukraine. In fish farms of the North-Eastern and Eastern regions of Ukraine, 26 species of parasites were found in herbivorous fish: 19 species in the silver carp (11 — protozoa, 1 — monogeneans, 4 — trematodes, 3 — parasitic crustaceans); 18 species in the grass carp (6 — protozoa, 1 — monogeneans, 4 — trematodes, 4 — cestodes, 3 — parasitic crustaceans); and 20 species in the bighead carp (10 — protozoa, 1 — monogeneans, 4 — trematodes, 2 — cestodes, 3 — parasitic crustaceans). 11 species (42.3%) of registered parasites were invasive; 18 species (69.2%) of the detected herbivorous fish’s parasites develop directly and 8 (30.8%) — with the participation of definitive and intermediate hosts; the fish is an additional (second intermediate) host in the life cycle of 6 species (23.1%) of parasites. Outbreaks of diseases caused by parasitic protozoa from the genera Myxobolus, Cryptobia, Chilodonella, and Ichthyophthirius have been reported in both fingerlings and two-year-olds. The protozoa from the genera Ichthyobodo, Trichodina, and Trichodinella were registered en masse only in fingerlings. Pathogens from the genus Dactylogyrus were more often registered among three-year-old silver and bighead carps. Metacercariae of Ichthyocotylurus variegatus were found en masse in fingerlings of the grass carp. Posthodiplostomum cuticola larvae in unfavorable farms were found with a high level of prevalence in fish of different age groups. Thong plerocercoids were more commonly recorded in two-year-old silver and bighead carps and fingerlings of the grass carp. The highest level of cestode infection with Bothriocephalus acheilognathi was recorded in fingerlings of the grass carp. Parasitic crustaceans Sinergasilus lieni with a high level of prevalence were registered in two-year-old and three-year-old fish. Crustaceans Lernaea cyprinacea massively affected two-year-old and three-year-old fish. Pathogens from the genera Trichodina, Cryptobia, and Chilodonella, and Dactylogyrus hypophthalmichthys, Posthodiplostomum cuticola, and Sinergasilus lieni were of the greatest epizootic significance for the silver carp; for the bighead carp — from the genus Myxobolus, (especially M. pavlovskii), Chilodonella piscicola, Ichthyophthirius multifiliis, Dactylogyrus aristichthys, Posthodiplostomum cuticola, Diplostomum spathaceum, Digramma interrupta, and Sinergasilus lieni; for the grass carp — Bothriocephalus acheilognathi, Ichthyocotylurus variegatus, Ligula intestinalis, Sinergasilus major, Lernaea cyprinacea, Ichthyobodo necator, and Ichthyophthirius multifiliis

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