Asian Carp (Big Head and Silver) in the Missouri River near Columbia, Missouri and their Feeding Habits
Russell G. Rhodes, Department of Biology
Missouri State University
This website is for educational purposes only. Permission to use any illustrations must be obtained from the author
A Comparison of Phytoplankton in an Integrated Water Column and in Foregut Analyses of BHC1 and SVC1 from L3, Missouri River near Columbia, Missouri from Samples Collected on March 4, 2004
Russell G. Rhodes, Department of Biology, Missouri State University
An initial analyses of phytoplankton found and counted in an integrated water column in the area of L3 on the Missouri River, Columbia, Missouri includes 21 taxa of algae. The most dominant in terms of units (single cells in this case) was a small species of Cyclotella, a diatom. Two taxa of green algae, Ankistrodesmus and Golenkinia were next in frequency (Fig 1).
In the foregut of BHC1 the algal content was similar with respect to the dominance of the small species of Cyclotella. However, there were other taxa present that were not a part or only a small part of the flora in the integrated water column (Fig. 2). These taxa included Navicula, Nitzschia, Suriella, and a large species of Synedra. Absent in the flora was Ankistrodesmus.
In the foregut of SVC1 were algae in proportions very similar to that contained in the integrated water column including a dominance of the small celled Cyclotella and a notable reduction of Suriella and an absence of the large celled Synedra and Nitzschia.
In comparing the foregut content of the two species of Asian carp, SVC1 appears from this initial comparison to feed more in the water column at a higher level. BHC1 seems to be grazing, in part, in the water column, but also along the bottom where the large celled species of Suriella, Navicula, and Nitzschia might be present. It was also noted that the foregut content of BHC1 contained much more vascular plant material as evidenced by vascular tissue of plants in the tissue and robust remains of zooplankton.
These are some algae that where collected in an integrated, 5m water sample by Duane Chapman, USGS, Columbia, Missouri.
Table 1. Selected Algae preserved in Lugol's Iodine and found in an integrated water column near the bridge at I 70 over the Missouri River, at Columbia, Missouri. Unless otherwise noted the magnification of the photos is 40X and each photo is a thumbnail, a larger image of which is to be obtained by clicking on the thumbnail.
|Asterionella||Chlamydomonas||Cyclotella (girdle view showing undulate valve)||Cyclotella (valve view)|
|Cymatopleura (valve view)||Cymatopleura (girdle view)||Dictyosphaerium
|Nitzschia||Peridinium||Suriella (girdle view)||Suriella (valve view)|
Table 2. Algae taken from the foregut of a silver carp (SVC1) collected on 19 March, 2004. The algae were preserved in Lugol's iodine.
|Melosira||Oscillatoria||Scenedesmus sp. a||Scenedesmus sp. b|
Table 3. Algae taken from the foregut of a bighead carp (BHC2) collected on 22 March, 2004 and BHC1 collected on 22 January 2004. The algae were preserved in Lugol's iodine.