Abstract
Bighead Carp (Hypophthalmichthys nobilis) are an invasive species expanding throughout the Mississippi River Basin. Understanding population characteristics of Bighead Carp (i.e., sex composition) within their invaded range can help agencies better manage those systems. Previous research has shown that external differences such as rough patches on the pectoral fins of Silver Carp (H. molitrix) can quickly and accurately determine gender. Since Bighead Carp are closely related to Silver Carp, they may also exhibit this pectoral fin sexual dimorphism. However, this gender determination technique has not been validated for Bighead Carp. Consequently, the objective of this study was to assess the utility of using the presence of a rough patch to identify Bighead Carp gender. Bighead Carp were collected from the upper Illinois River during 2017 by contracted commercial fisherman using gill and trammel nets. Gender was first identified by the presence or absence of a pectoral fin rough patch and then verified by gonadal investigation. Bighead Carp total lengths varied between 526 mm and 1200 mm with a mean total length of 821.5 (SE = 6.92 mm). Preliminary analysis of 460 Bighead carp shows an overall classification success rate of 77.7% with greater success occurring classifying females (87.2%) than males (69.4%). A chi square test revealed a significant difference between the actual gender and gender determined via the pectoral fin (p value
Original language | English (US) |
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State | Published - 2018 |
Event | 2018 Midwest Fish and Wildlife Conference - Milwaukee, United States Duration: Jan 28 2018 → Jan 31 2018 Conference number: 78 |
Conference
Conference | 2018 Midwest Fish and Wildlife Conference |
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Country/Territory | United States |
City | Milwaukee |
Period | 1/28/18 → 1/31/18 |
Keywords
- INHS