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Joe J. Warren

Publications and source records attributed to Joe J. Warren.

2 recordsLinked to original sources
USGS2023

Monitoring native nonsalmonids for the incidence of gas bubble trauma downstream of Snake and Columbia River dams during the spring spill season, 2022

In 2020, a new spill program was implemented to aid the downstream passage of juvenile salmonids at mainstem dams on the Snake and Columbia rivers. Under this program, the total dissolved gas (TDG) cap was increased to 125% and monitoring of native nonsalmonids for gas bubble trauma (GBT) became a requirement. The primary objective of this work was to measure the incidence and severity of GBT in native nonsalmonids resulting from increased juvenile fish passage spill and associated levels of TDG during the spring spill period. Native nonsalmonids were collected downstream from Bonneville, McNary, Ice Harbor, and Lower Granite dams and examined for the incidence and severity of GBT in 2022. Fish were collected at each location weekly (4 April to 13 June) during the spring spill period by backpack electrofishing and beach seining. Washington and Oregon state water quality agencies established minimum and target sample sizes for monitoring, but the minimum sample size of 50 fish and target sample size of 100 fish were not met in all weeks at individual projects due to high water flows and resulting low fish collections. Collected fish were examined for GBT according to the criteria and protocol established for the regional smolt monitoring program (SMP). Overall, GBT incidence and severity rankings were low and did not exceed the thresholds that would have triggered changes to the spill program. Using SMP criteria, maximum weekly GBT incidences were 1.9% downstream from Bonneville Dam, 8.6% downstream from McNary Dam, 7.7% downstream from Ice Harbor Dam, and 3.4% downstream from Lower Granite Dam. In contrast to 2021, several species showed signs of GBT in 2022, and GBT was commonly observed in fins and body locations other than the unpaired fins and eyes (i.e., SMP criteria). In general, the observed signs of GBT according to SMP criteria were not severe (i.e., ranks 1 and 2). Although TDG reached the gas cap, particularly late in the spring spill season, GBT incidence rates were not high probably due to factors such as habitat-related variability in TDG, species composition and varying tolerance to high TDG, low power to detect GBT incidence at small sample sizes, and unknown exposure history.

Oregon, Washington↗
USGS2021

Monitoring native, resident nonsalmonids for the incidence of gas bubble trauma downstream of Snake and Columbia River Dams, 2021

In 2020, a new spill program was implemented to aid the downstream passage of juvenile salmonids at mainstem dams on the Snake and Columbia rivers. Under this program, the total dissolved gas (TDG) cap was increased to 125% and monitoring of native, resident nonsalmonid (NRN) fishes for gas bubble trauma (GBT) became a requirement. The primary objective of this work was to measure the incidence and severity of GBT in NRN fishes resulting from increased juvenile fish passage spill and associated levels of TDG during the spring spill period. A secondary objective was to measure the incidence of GBT in incidentally collected juvenile salmonids when NRN sample size targets were met. NRN fishes were collected downstream from Bonneville, McNary, and Ice Harbor dams and examined for the incidence and severity of GBT in 2021. Fish were collected at each location weekly (6 April to 17 June) during the spring spill period by backpack electrofishing and beach seining. Washington and Oregon state water quality agencies established minimum and target sample sizes for monitoring, and in all weeks the minimum sample size of 50 fish was met and in most weeks the target sample size of 100 fish was met. Collected fish were examined for GBT according to the criteria and protocol established for the regional smolt monitoring program (SMP). Overall, GBT incidence and severity rankings were low and did not exceed the thresholds that would have triggered changes to the spill program. Using SMP criteria, weekly GBT incidences ranged from 0 to 1.0% downstream from Bonneville Dam, 0 to 6.2% downstream from McNary Dam, and 0 to 1.9% downstream from Ice Harbor Dam. Except for one three-spined stickleback (Gasterosteus aculeatus) collected downstream of Bonneville Dam, the only NRN species that showed signs of GBT was sculpin spp. GBT was observed in sculpin in body locations other than the unpaired fins and eyes (i.e., SMP criteria). If GBT incidence in all areas on the fish (i.e., paired fins, unpaired fins, eyes, body) are combined, then weekly GBT incidence rates increase and range from 0 to 4.3% downstream from Bonneville Dam, 0 to 15.4% downstream from McNary Dam, and 0 to 4.7% downstream from Ice Harbor Dam. This illustrates the effect of using different criteria to determine the incidence of GBT in NRN fishes. It also shows how the proportion of a species in a sample that is more prone to show GBT can influence GBT incidence rate. On a number of occasions, incidental catch of subyearling fall Chinook salmon were examined for GBT downstream of Bonneville Dam but none showed any signs. The DG was generally below 120% and never reached the 125% gas cap during the spring spill season, which may be why GBT incidence rates were so low as past research has shown that GBT signs in NRN fishes are relatively low below this TDG level.

Oregon, Washington↗