BPA Fish and Wildlife FY 1997 Proposal

Section 1. Administrative
Section 2. Narrative
Section 3. Budget

see CBFWA and BPA funding recommendations

Section 1. Administrative

Title of project
Optical Detection of Gas Bubbles in Fish

BPA project number   5500400

Business name of agency, institution or organization requesting funding
U. S. Department of Energy

Sponsor type   TN-Federal Agency

Proposal contact person or principal investigator
 NameDr. S. Marshall Adams
 Mailing addressOak Ridge National Laboratory
P. O. Box 2008, MS 6036
Oak Ridge, TN 37831-6036

BPA technical contact   Bill Maslon, EWI 503/239-5549

Biological opinion ID   Number 16

NWPPC Program number   

Short description
This project will investigate the feasibility of using light ransmission or reflectance to remotely monitor bubbles or bubble-caused trauma in juvenile salmonids with minimal handling and without killing the fish.

Project start year   1997    End year   1998

Start of operation and/or maintenance   0

Project development phase   Implementation

Section 2. Narrative

Related projects
This project is related to ongoing work on acoustic methods for
monitoring gas bubble trauma (Battelle- Pacific Northwest National
Laboratory) , another method with similar objectives. Acoustic methods
have not yet been shown satisfactory.

Project history

Biological results achieved

Annual reports and technical papers

Management implications

Specific measureable objectives
The specific measurable objective is to have an evaluation of the
feasibility of using optical (transmission or reflectance) techniques to
remotely (without handling fish out of water) monitor the presence and
severity of gas bubble trauma in juvenile salmonids as based on theoretical
analyses, laboratory tests, and proposed monitoring situations.

Testable hypothesis
The testable hypothesis is that there will be a quantitative
relationship between the presence and severity (number, size) of gas
bubbles associated with gas bubble trauma in a fish and the properties of
light received after light beams are transmitted through or reflected from
fish tissues in a living fish constrained underwater in a small container.

Underlying assumptions or critical constraints
The underlying assumption of this work is that light beams passing
through or reflected from juvenile salmonids will have their properties
altered in a quantifiable way with the presence of bubbles in tissues such
as fins, lateral line, and gills (bubble presence is believed indicative of
pathological symptoms of total gas supersaturation that can lead to
mortality). Several forms and wavelengths of the light source and several
receptor features such as total absorbance and wavelength selectivity are
candidates for study. It is assumed (and will be tested) that a light beam
can be directed through susceptible tissues and received at the other side
in such a way as to detect these changes. It is also assumed (and will be
tested) that a holding container can be devised that will immobilize a
single fish without removing it from the water so that the optical
measurements can be made with little stresss and no mortality. It should
be possible to develop a monitoring protocol combining successful
optical-measurement and fish-holding techniques. These experiments will
require a source of fish (most likely hatchery-raised rainbow trout) that
have been exposed experimentally to varying degrees of water
supersaturation. Alternative measures of bubble presence and quantity will
be needed, such as visual (microscopic) observation of the same tissues
after optical testing.

Fish (most likely hatchery-raised juvenile rainbow trout) will be
exposed to supersaturated total dissolved gases in an experimental tank to
yield different levels of signs of gas bubble trauma (obtainable from
different lengths of exposure and different levels of supersaturation). An
optically transparent holding container will be designed that will allow
fish to be immobilized in a light beam without killihg the fish either
during testing or in transfer in and out of the container. Numerous
combinations of light source and receptor will be tried to see if bubble
presence can be identified and quantified. Quantitative comparisons will
be made between these methods and established techniques of microscopic
counts of bubbles (using sufficient fish and standard statistical tests for
establishing differences). If the method is rapidly determined to be
successful, it may be possible to design an experiment to distinguish
between the etiology of long-term exposures to low levels of total gas
supersatureation and short exposures to high gas saturations, which appear
to show a different chronology of bubble formation in relation to deaths.
Such a distinction could be useful for estimating the types of exposure
received by fish monitored at fixed sites. The studies will be evaluated
for the efficacy of the optical technique for routine monitoring downstream
migrating salmonids. If feasible, initial adaptations to a monitoring
environemnt will be made, including fish handling, use and maintenance of
optical equipment, and data analysis.

Brief schedule of activities
October 1996-April 1997: Exploratory testing of various
fish-holding and optical devices.
May-July 1997: Quantitative testing of relationships between optical
transmission/reflectance and microscopic methods.
August -September 1997: Preparation of initial evaluation in a progress
October 1997-July 1998: Further testing and quantification, as
appropriate. If feasible, test the difference in etiology between slowly
developing gas bubble trauma from low gas supersaturation values and
rapidly lethal symptoms from high gas saturations. If feasible, develop a
monitoring procedure of use at routine monitoring stations, including fish
handling, use and maintenance of optical equipment, and automated data
August-September 1998: Preparation of final report and assistance to the
=46ish Passage Center in installing test monitors in the field (if

Biological need
The underlying need is for a non-lethal method for monitoring signs
of gas bubble disease in migrating juvenile salmonids. Spill of water at
dams on the Columbia and Snake rivers causes supersaturation of atmospheric
gases in tailwaters that can be cumulative as water moves downriver through
several dams. There can be both uncontrolled spill (from river flow that
exceeds turbine capacity) and controlled spill (used as a managment tool to
divert juvenile outmigrants from the turbines where high mortality can
occur). Controlled spill attempts to balance the fish-survival gains from
avoiding turbines with the added risks of mortalities caused directly or
indirectly from gas supersaturation. Both physical (% saturation) and
biological (indexes of bubble signs in fish) criteria are used for fish
protection and are evaluated through monitoring. The quantitative
relevance of both physical and biological data for protecting fish have
been questioned. Biological monitoring has been criticized for killing
fish (for assays such as gill bubbles) and being ineffective using only
non-lethal visual methods. All biological methods and signs used to date
are difficult to relate to mortality. Thus, a simple, non-lethal method
for quantifying gas bubble incidence in fish in relation to exposure to
supersaturated gases is needed. The Gas Bubble Trauma Working Group,
convened by the Natiojal Marine Fisheries Service in 1994, recommended
research on this topic.

Critical uncertainties
The critical uncertainty that the research addresses is the
validity of currently used non-lethal, microscopic signs of bubbles in fish
tissues for estimating the risk of fish populations to mortality from gas
bubble trauma. The critical uncertainty for the proposed work is whether
optical methods of transmittance or reflectance could do any better.

Summary of expected outcome
The expected outcome (if the research is successful) is a method
for monitoring juvenile salmonids with minimal handling and no removal from
water that will yield (1) a quantitatively useful index of the
manifestation of gas bubble trauma and (2) a monitoring protocol that can
be used at monitoring stations on the Columbia and Snake rivers and

Dependencies/opportunities for cooperation
The experimental work will require the interactive participation of
biologists and optical engineers, both of which are available at Oak Ridge
National Laboratory. Availability of young fish will be critical, and
these can be made available commercially or by Tennessee state hatcheries.
In the second year of study (assuming success in the first year), the
transfer of laboratory-scale studies to design of a field monitoring system
will be aided by consultation with the Fish Passage Center and the National
Biological Service, which oversee the Smolt Monitoring Program on the
Columbia and Snake Rivers. Actual monitoring implementation, if any, will
require subsequent verification with juvenile salmon (perhaps by NBS) and
development of field monitoring equipment.

There are no known risks to either fish populations of the
Columbia-Snake basin or to human investigators from this work. Any use of
lasers as optical devices will be guided by stringent controls in place at
ORNL to ensure investigator safety.

Monitoring activity
The project's outcomes will be monitored by annual progress
reports, a final report, and draft paper(s) for open-literature
publication. Results will be made known to interested colleagues and
agencies as soon as is reasonable by informal contacts, meetings, and
presentations at conferences.

Section 3. Budget

Data shown are the total of expense and capital obligations by fiscal year. Obligations for any given year may not equal actual expenditures or accruals within the year, due to carryover, pre-funding, capitalization and difference between operating year and BPA fiscal year.

Historic costsFY 1996 budget data*Current and future funding needs
(none) New project - no FY96 data available 1997: 150,000
1998: 150,000

* For most projects, Authorized is the amount recommended by CBFWA and the Council. Planned is amount currently allocated. Contracted is the amount obligated to date of printout.

Funding recommendations

CBFWA funding review group   Mainstem

Recommendation    Tier 3 - do not fund