Little Calumet River Rapid Response Fish Identification and Enumeration Branch Summary Report

Transcription

1 Little Calumet River Rapid Response Fish Identification and Enumeration Branch Summary Report Introduction A rotenone rapid response was completed on a 2.6-mile section of the Little Calumet River immediately downstream of the T. J. O Brien Lock and Control Works during May 19-28, The treatment zone measured 173 surface acres and it included the river main stem from O Brien Lock and Dam to the Beaubien Woods Forest Preserve boat launches, the mouth of the Grand Calumet River, and the Marine Services Corporation Marina. The primary purpose of the response was to determine the abundance of bighead and silver carp (Asian carp) in this portion of the Chicago Area Waterway System (CAWS) that had previously produced multiple positive detections for Asian carp environmental DNA. The Fish Identification and Enumeration Branch processed all fish recovered during the operation. Specifically, branch workers examined all recovered fish for the presence of Asian carp and identified to species, counted and measured lengths and weights from a subsample of these fish. Data from recovered fish were then used to estimate numeric and biomass standing stocks for all species in the treatment zone. Methods Fish recovery for the rotenone application zone lasted for 6 days and it continued for an additional 3 days in the area below the downstream block net. All recovered fish were netted from boats and transported in 55-gallon drums to the fish identification station at T. J. O Brien Lock and Control Works where they were processed and loaded into plastic lined roll off dumpsters for transport to a landfill. The weight of each dumpster load was determined at the landfill and load weights were combined to provide a measure of the total weight of recovered fish. Fish processing protocol varied over the 9-day recovery period. On days 1-3 after rotenone application (May 20-23, 2010), recovered fish barrels were lifted from boats with an excavator and dumped in a 60-foot x 120-foot portable containment berm where they were sorted by species and counted. Subsamples of identified fish were measured to the nearest mm total length and weighed to the nearest gram on the first two days of recovery. In addition, abundance of unidentified small-bodied minnows was estimated during the first two days by dividing the bottom of the containment berm into square-foot sections, counting all minnows within a subsample of sections, and multiplying the average number of fish per section by the total area of the berm that contained small fish. A subsample of small fish from the berm floor (N = 1,784) was collected and preserved in jugs with formalin for later identification to species in the laboratory. Unidentified minnows were assigned to species categories based on percent composition of identified minnows in the preserved subsample. Decomposition precluded minnow counts and measurement of lengths and weights after the second day of recovery. On days 4-9 after rotenone application, barrels of recovered fish were dumped into a bobcat bucket and examined for the presence of Asian carp before being loaded into roll off dumpsters. Barrels of fish recovered from outside the rotenone application zone were tagged with brightly colored ribbon so that they could be examined for Asian carp and weighed separately from fish recovered within the application zone. No attempt was made to identify other species or count fish from outside the application zone, but a total weight was determined for these fish at the landfill. Estimates of number and weight of each species of fish recovered in the application zone were determined with data from counts of identified fish, estimates of average fish weight, and the combined mass of fish weighed at the landfill. We estimated total weights of individual fish species for the entire recovery period by calculating a weighted mean of fish weight for each species (average weight x number counted), determining the percent composition of the weighted means (weighted mean for each species divided by the sum of weighted means), and then multiplying these percentages by the total weight of recovered fish. Estimates of total numbers recovered were determined for each species by dividing species specific total weight estimates by average weights. Weights were not determined for small-bodied minnows so their numbers were not extrapolated over the entire recovery period. Estimates of minnow abundance during the first three days of recovery were considered representative of the entire recovery period because few small-bodied fishes were observed in the later days of recovery. Losses of small fish to decomposition and predation by an abundant resident gull population may explain this trend in small fish recovery.

2 Results The Little Calumet River near T. J. O Brien Lock and Control Works supported an abundant fish community that had high species richness. We recovered an estimated 67, 224 fish from 38 species and two hybrid groups (Table 1). These fish had a combined weight of 97,720 pounds. An additional 36,100 pounds of fish were recovered from the area outside of the treatment zone. No bighead or silver carp were recovered or observed during the operation. However, a number of other non-native taxa were sampled, including grass carp, round goby, white perch, goldfish, common carp, and alewife. In contrast, the sample included some interesting native species, such as a grass pickerel, four brown bullhead, four flathead catfish, and numerous ghost shiners. Reasonable habitat variability, decent water quality, and direct hydrologic connections with Lake Michigan may explain the observed variety of species inhabiting this reach of the river. Despite high species richness, the fish community was dominated by common carp and gizzard shad both numerically and in terms of biomass. Gizzard shad made up 33% of the number of fish sampled (rank = 1) and 20% of the weight sampled (rank = 2), whereas common carp made up 15% of the number sampled (rank = 2) and 63% of the weight sampled (rank = 1; Table 1). Other numerically abundant fish in the sample included ghost shiner (10%), emerald shiner (6%), alewife (5%), freshwater drum (5%), bluntnose minnow (4%), goldfish (3%), round goby (3%), channel catfish (3%), rock bass (2%), pumpkinseed (2%), and white perch (2%). Species with relatively high estimates of total weight included freshwater drum, channel catfish, black buffalo, goldfish, and grass carp. These species combined to make up 14% of the total weight of recovered fish. We estimated that the sampled reach of the Little Calumet River had a density of 389 fish/acre and a standing stock biomass of 565 pounds per acre. This biomass estimate is similar to farm ponds in Illinois, which typically contain fish/acre, but well below the 1,000-2,000 pounds/acre reported for some Mississippi River backwaters. Standing stock estimates ranged from <1 fish/acre and 0.01 pounds/acre for several species to 129 fish/acre for gizzard shad and 387 pounds/acre for common carp (Table 1). Standing stock of sport fish generally was low. Estimates were highest for freshwater drum (18 fish/acre and 44 pounds/acre) and channel catfish (11 fish/acre and 14 pounds/acre), but low for largemouth bass, smallmouth bass, flathead catfish, white bass, yellow perch, white and black crappie, and other sunfish species (all <8 fish/acre and <2.5 pounds/acre). A total of 38,143 fish were counted (including estimates of minnow abundance) during the three days that fish were enumerated (Table 2). The total weight of counted fish was 47,080 pounds or 48% of the total weight of all fish recovered from the application zone. Numbers of recovered fish were lowest on the day rotenone was applied and highest on day 2 after application. There was a substantial decline in the number of fish recovered by day 3. The percent composition of each day s sample remained fairly consistent through time (Table 2), although common carp and gizzard shad were more prevalent and small-bodied fishes less prevalent on the third day of recovery. We measured total lengths of 1,469 fish and weighed 1,383 of them (Table 3). Grass carp had the largest average length and weight (34.1 inches pounds) and this species produced the largest individual fish (43.0 inches and 39.6 pounds). Other large individuals sampled were a common carp that weighed pounds, a flathead catfish (16.02 pounds), black buffalo (13.20 pounds), smallmouth buffalo (9.16 pounds), freshwater drum (6.13 pounds), channel catfish (5.53 pounds), gizzard shad (2.73 pounds), smallmouth bass (2.40 pounds), and largemouth bass (2.24 pounds). Populations of most sampled species also contained smaller juvenile fish (see minimum lengths, Table 3). The occurrence of juveniles suggests that successful reproduction may occur in this portion of the river or that habitat, water quality, and food resources are suitable for juvenile fish survival and growth.

3 Table 1. Estimated total number and percentage, total weight and percentage, and standing stock for 38 species of fish and two hybrid groups recovered from the Little Calumet River near T. J. O'Brien Lock and Dam during six days of recovery after rotenone application on May 20, Weight was not measured for most minnow and darter species. Estimated Estimated Estimated Standing Stock Total Total Number Pounds Species Number Percent Weight Percent per acre per acre Alewife 3, Black buffalo , Black bullhead Black crappie Bluegill Bluntnose minnow 2, Brown bullhead <0.1 Channel catfish 1, , Common carp 9, , Emerald shiner 4, Fathead minnow Flathead catfish 8 < Freshwater drum 3, , Ghost shiner 6, Gizzard shad 22, , Golden shiner Goldfish 2, , Goldfish x Common carp hybrid Grass carp Grass pickerel 2 <0.1 < <0.1 Green sunfish <0.1 Hybrid sunfish 2 <0.1 < <0.1 Johnny darter 1 < Largemouth bass Orangespotted sunfish <0.1 Pumpkinseed 1, Rock bass 1, Round goby 2, <0.1 Smallmouth bass Smallmouth buffalo 12 < Spotfin shiner Spottail shiner Warmouth 18 < <0.1 White bass White crappie White perch 1, White sucker Yellow bass 10 < <0.1 Yellow bullhead , Yellow perch All species 67,224 97,

4 Table 2. Number and percentages of fish recovered and counted from the Little Calumet River near T. J. O'Brien Lock and Dam during the first three days after rotenone application on May 20, Number Percent Species Day 1 Day 2 Day 3 Total Day 1 Day 2 Day 3 Alewife 505 1, , Black buffalo <0.1 <0.1 Black bullhead Black crappie Bluegill Bluntnose minnow 170 2, , Brown bullhead < Channel catfish Common carp 2,088 1,215 1,498 4, Emerald shiner 186 1, , Fathead minnow Flathead catfish Freshwater drum 381 1, , Ghost shiner 54 6, , Gizzard shad 2,861 2,667 5,374 10, Golden shiner Goldfish , Goldfish x Common carp hybrid <0.1 Grass carp Grass pickerel < Green sunfish Hybrid sunfish < Johnny darter <0.1 <0.1 Largemouth bass Orangespotted sunfish Pumpkinseed Rock bass Round goby , Smallmouth bass <0.1 <0.1 Smallmouth buffalo <0.1 <0.1 <0.1 Spotfin shiner Spottail shiner < Warmouth <0.1 White bass < White crappie White perch White sucker Yellow bass Yellow bullhead Yellow perch All species 7,528 21,567 9,048 38,143

5 Table 3. Mean, minimum, and maximum total lengths and weights for a subsample of fish recovered from the Little Calumet River near T. J. O'Brien Lock and Dam during the first two days after rotenone application on May 20, Mean Minimum Maximum total total total Mean Minimum Maximum Number length length length Number weight weight weight Species measured (inches) (inches) (inches) weighed (pounds) (pounds) (pounds) Alewife Black buffalo Black bullhead Black crappie Bluegill Bluntnose minnow Brown bullhead Channel catfish Common carp Emerald shiner Fathead minnow Flathead catfish Freshwater drum Ghost shiner Gizzard shad Golden shiner Goldfish Goldfish x Common carp hybrid Grass carp Grass pickerel Green sunfish Hybrid sunfish Johnny darter Largemouth bass Orangespotted sunfish Pumpkinseed Rock bass Round goby Smallmouth bass Smallmouth buffalo Spotfin shiner Spottail shiner Warmouth White bass White crappie White perch White sucker Yellow bass Yellow bullhead Yellow perch Grand Total 1,469 1,383

6 Participating Organizations The Illinois Department of Natural Resources (IDNR, with support from the Monitoring and Rapid Response (MRR) workgroup of the Regional Coordinating Committee (RCC), implemented the Asian Carp Rapid Response Plan (RRP) to take the necessary actions along the Little Calumet River. In addition, local organizations, federal and state agencies, non governmental agencies (NGO), and industry stakeholders were on hand to assist (IDNR) in order to ensure a successful operation. LOCAL Cook County Forest Preserve District (CCFPD) OTHER Commercial Fishermen STATE Illinois Emergency Management Agency (IEMA) Indiana Department of Natural Resources (IN DNR) Tetra Tech EM Inc. SET Environmental Carus, Inc. Illinois Department of Natural Resources (IDNR) Illinois Environmental Protection Agency (IEPA) FEDERAL U.S. Army Corps of Engineers (USACE) U.S. Coast Guard (USCG) U.S. Department of Transportation (USDOT) U.S. Environmental Protection Agency (USEPA) U.S. Fish and Wildlife Service (USFWS) U.S. Geological Survey (USGS) U.S. Department of Agriculture (USDA) NON-GOVERNMENT American Red Cross of Greater Chicago (ARCGC) Great Lakes Fishery Commission (GLFC) Metropolitan Water Reclamation District of Greater Chicago (MWRD) Illinois Natural History Survey (INHS)

7 Response Participants No. of Personnel Responding field personnel 310 Command and ICP Staff Agency observers/visitors onsite Information from: OPERATION PELICAN: ASIAN CARP RAPID RESPONSE May 20 through May 27, 2010 Prepared for U.S. Environmental Protection Agency Great Lakes National Program Office, Illinois Department of Natural Resources, Submitted by Tetra Tech EM Inc. 1 South Wacker Drive, 37th Floor Chicago, IL September