U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2016–3057

August 2016

Prepared in cooperation with the Missouri River Recovery Program

The Missouri River Scaphirhynchus albus (Pallid Sturgeon) 

Effects Analysis

What is an Effects Analysis?

The Missouri River Pallid Sturgeon Effects Analysis (EA) 

was designed to assess how Missouri River management has 

affected—and may affect—the endangered Scaphirhynchus 

albus (pallid sturgeon) population. The idea of an EA is practical 

and conceptually simple. An EA integrates three components to 

achieve a better understanding of a listed species and what can 

be done to improve its status (Murphy and Weiland, 2011):

• Collection of reliable scientific information,

• Critical assessment and synthesis of available data and 

analyses, and 

• Analysis of the effects of management actions on listed 

species and their habitats. 

The Missouri River Pallid Sturgeon EA emerged from the 

recognition that the direction and focus of the Missouri River 

Recovery Program would benefit from an updated, thorough 

evaluation of what is known, what is not known, and what needs 

to be known for effective actions (Doyle and others, 2011). 

The Missouri River Pallid Sturgeon EA core team consists 

of sturgeon and river experts from the U.S. Geological Survey, 

U.S. Army Corps of Engineers, U.S. Fish and Wildlife Service, 

and Mississippi State University. The EA core team has also benefited from extensive collaboration and reviews by experts from 

State agencies and universities. 

The EA deliberations and results have been documented 

in an integrative report (Jacobson and others, 2016a), which is 

envisioned as the initial report in an ongoing series of updates 

that will support adaptive management of the Missouri River. 

The integrative report is a synthesis of the three parts of an 

effects analysis, with an emphasis on development of lines of 

evidence for how future management actions are likely to affect 

the pallid sturgeon population. The integrative report received 

thorough technical peer review by seven experts and the Independent Science Advisory Panel (ISAP) of the Missouri River 

Recovery Implementation Committee.

Three additional reports have been published by the EA 

core team to serve as the foundation for the integrative report 

(fig. 1). The first report (Jacobson and others, 2015a) is a compilation and assessment of available information and quantitative models that can be used to understand historical and future 

changes of pallid sturgeon populations. The second report 

(Jacobson and others, 2015b) describes conceptual ecological 

models (CEMs) developed to document and illustrate a global 

set of ecological relations for Missouri River pallid sturgeon. 

The third report (Jacobson and others, 2016b) documents the 

process of filtering the global set of hundreds of hypotheses that 

emerged from the CEMs. The EA used expert-opinion surveys and existing evidence to formulate and filter hypotheses, 

converging on an initial 21 working management hypotheses. 

The EA integrative report assesses these 21 working management hypotheses to document existing knowledge and explore 

potential actions (table 1).

Figure 1. Published reports from the Missouri River Pallid Sturgeon Effects Analysis.
Table 1. Summary table of working action hypotheses, findings, and routings (modified from Jacobson and others, 2016a).

Number Working management 

hypothesis Findings Potential routing

Upper Missouri River

Alter flow regime at Fort Peck Dam

1 Naturalized flows, food and energetic 

demands

Theoretical support but inadequate data to model and forecast 

population response

Research on bioenergetics, hydrodynamic models, comparative 

field experiments

2 Spring flow pulses, aggregation and 

spawning cues

Theoretical support, inference from other sturgeon species, but 

inadequate data to model and forecast population response

Research, monitor responses to events, possible pulsed flow 

experiment

3 Decreased spring flows and velocities, reduced driftPotential effective action, subject to contingent information Research to resolve anoxia, use of Yellowstone, interstitial hiding, 

retarded drift

Temperature control at Fort Peck Dam

4 Increased temperature, increased 

productivity

Theoretical support but inadequate data to model and forecast 

population response

Research on bioenergetics, hydrodynamic models, comparative 

field experiment

5 Increased temperature, increased 

growth, decreased drift

Potential effective action, subject to contingent information Research to resolve anoxia, use of Yellowstone, interstitial hiding, 

retarded drift

Sediment augmentation at Fort Peck Dam

6 Increased turbidity, decreased 

predation

Theoretical support, but laboratory data equivocal; no specific 

models for population response

Research on predation egg, embryos, free embryos

Yellowstone River

Passage at Intake Diversion Dam

7 Increased potential dispersal distance Potential effective action, subject to contingent information Implementation likely. Complement with research, robust monitoring and evaluation

Upper Missouri and Yellowstone Rivers

Propagation in the upper basin

8 Improved stocking strategy, size 

classes

Potential effective action, subject to hatchery capacities Implemented, validate with monitoring, assessment. Research on 

optimization

9 Improved stocking strategy, genetic 

diversity and population viability

Theoretical support, no specific data, models to forecast population responseImplemented, validate with monitoring, assessment. Research on 

linking parentage and population viability

Lake Sakakawea

Drawdown at Lake Sakakawea

10 Increased potential drift distance Potential effective action, subject to contingent information. Research to resolve anoxia, use of Yellowstone, interstitial hiding, 

retarded drift

Lower Missouri River

Alter flow regime at Gavins Point Dam

11 Spring flow pulses, aggregation and 

spawning cues

Theoretical support, inference from other sturgeon species, but 

inadequate data to model and forecast population response

Research, monitor responses to events, possible pulsed flow 

experiment

12 Naturalized flows, increased 

productivity

Theoretical support, inference from hydrodynamic models, but 

data inadequate to model, forecast population response

Research on bioenergetics, comparative field experiments, 

possible pulse flow experiment.

13 Naturalized flows, decreased 

energetic demands

Theoretical support, inference from hydrodynamic models, but 

data inadequate to model, forecast population response

Research on bioenergetics, comparative field experiments, 

possible pulse flow experiment.

14 Decreased spring flows and 

velocities, reduced dispersal

Theoretical support, inference from hydrodynamic models, but 

data are equivocal as limiting factor and population response

Research into drift dynamics

Temperature management at Gavins Point Dam

15 Naturalized temperatures, increased 

aggregation and spawning cues

Theoretical support, inference from other sturgeon species, data 

equivocal about magnitude of change, population response

Research, monitor responses to events

Channel reconfiguration

16 Reconfigure channel for spawning 

habitats

Theoretical support, support from sturgeon species, hydrodynamic models, but data are equivocal as limiting factor and 

population response

Research in spawning dynamics, comparative field experiment

17 Reconfigure channel for food-producing habitatsTheoretical support, inference from hydrodynamic models, but 

data are equivocal as limiting factor and population response

Implemented in part, comparative field experiment, validate with 

monitoring, assessment

18 Reconfigure channel for foraging 

habitats

Theoretical support, inference from hydrodynamic models, but 

data are equivocal as limiting factor and population response

Implemented in part, comparative field experiment, validate with 

monitoring, assessment

19 Reconfigure channel for interception 

habitats

Theoretical support, inference from hydrodynamic models, but 

data are equivocal as limiting factor and population response

Possibly implemented in part, validate with monitoring, assessment, comparative field experiments

Propagation in the lower basin

20 Improved stocking strategy, size 

classes

Potential effective action, subject to hatchery capacities. Implemented, validate with monitoring, assessment. Research on 

optimization

21 Improved stocking strategy, parentage and fitnessTheoretical support, no specific data, models to forecast population responseImplemented, validate with monitoring, assessment. Research on 

linking parentage and population viability
The geographic scope of the EA is the Upper Missouri 

River main stem from Fort Peck Dam in Montana to the headwaters of Lake Sakakawea, the Yellowstone River upstream from 

the confluence with the Upper Missouri River, and the Lower 

Missouri River main stem from Gavins Point Dam to the confluence with the Mississippi River at St. Louis, Missouri. The scope 

also includes an unspecified distance downstream in the Mississippi River and various tributaries to these river segments that 

might be occupied by pallid sturgeon (fig. 2).

FORT PECK

 DAM

GARRISON

 DAM

INTAKE 

 DAM CANYON FERRY 

DAM

OAHE DAM

BIG BEND DAM

FORT RANDALL DAM

GAVINS POINT DAM

Sioux City, 

Iowa

Omaha,

Nebraska

Kansas City, 

Missouri

St. Louis, 

Missouri

Effects analysis river segments

Possible extensions of effects analysis

CARTERSVILLE

DAM

35°

40°

45°

110° 100° 90°

Base data from U.S. Geological Survey digital data, 1999

USA Contiguous Lambert Conformal Conic Projection

COLORADO

WYOMING

MONTANA

NORTH DAKOTA

SOUTH 

DAKOTA

MINNESOTA

NEBRASKA

IOWA

MISSOURI

KANSAS

MILES

KILOMETERS

Missouri River

EXPLANATION

Upper Missouri River

Yellowstone River

Platte River

0

0

100

100

200

200

300

300

400 MILES

400 KILOMETERS

RIVER

Mississippi River

Figure 2. Geographic scope of the Missouri River Pallid Sturgeon Effects Analysis (Jacobson and others, 2016b).

Information Gaps—A Key Finding

A key finding of the EA has been the extent of uncertainties 

in pallid sturgeon biology. Fundamental information gaps limit 

the ability to quantify how management actions will propagate 

to changes in the pallid sturgeon population. This does not mean 

that scientists have not made progress in understanding pallid 

sturgeon. In fact, the EA reports document that a substantial 

body of pallid sturgeon science has been developed during the 

past 20 years. The challenge to the science has been to understand critical population processes of a very rare fish that lives in 

a deep, fast, and muddy river where direct observation is nearly 

impossible.

Hypotheses, Lines of Evidence, and Models

Despite these gaps, a specific charge to the EA team was 

to develop a framework of the best models available to guide 

decision making and evaluate costs and benefits of management 

actions. Even in the presence of substantial predictive uncertainties, a modeling framework is useful for structuring hypotheses, 

exploring sensitivities of populations to management actions, 

prioritizing science needs, and synthesizing information from 

monitoring data. The EA integrative report presents the best-available quantitative models 

and other lines of evidence

to predict how future

management may affect 

pallid sturgeon population 

responses.

For some of the 

21 working management hypotheses, lines 

of evidence are limited 

to theoretical deduction, inference from rare 

empirical datasets, or 

expert opinion. Useful 

simulation models have 

been developed to predict 

the effects of management actions on survival 

of drifting free embryos 

in the Upper Missouri and 

Lower Yellowstone Rivers, and to assess effects 

of flow and channel 

reconfigurations on habitat 

availability in the Lower 

Missouri River (fig. 3). 

We have also developed 

a population dynamics 

model that can be used to 

assess sensitivity of the 

population to survival of 

specific life stages, evaluate hypotheses related to 

stocking decisions, and 

explore other management 

scenarios.

Consideration of lines of evidence for each of the 21 working management hypotheses includes a discussion of how the 

degree of uncertainty and risk associated with each hypothesis 

may guide science and implementation strategies. Strategies 

may be full implementation in the field, limited implementations 

as field-scale experiments, or further research (in the case of 

greatest uncertainty). The EA emphasizes that scientific progress 

in understanding the reproductive ecology of pallid sturgeon 

will require coordinated efforts in laboratory and field research. 

Although field-based research results will be most compelling, 

some important parts of the pallid sturgeon life cycle cannot be 

observed in the field, so results will need to be extrapolated from 

laboratory studies and model-based inferences.
Effects Analysis and Adaptive 

Management

The considerable uncertainties documented 

in the pallid sturgeon EA integrative report 

point to an adaptive-management approach for 

this rare fish and its ecosystem. Under adaptive 

management, hypotheses guide implementations 

of actions that are designed as learning experiments, and new information is used to improve 

management decisions. Importantly, hypotheses 

filtered early in the EA process can be resurrected and addressed as needed to explain new 

observations. Under adaptive management, a 

persistent EA process can be envisioned as a 

means to continually assess and assimilate science information and ensure the information is 

relevant and actionable for decision making.

References Cited

Doyle, Martin; Murphy, Dennis; Bartell, 

Steven; Farmer, Adrian; Guy, C.S.; Palmer, 

Margaret; and Turner, Robert, 2011, Missouri River Recovery Program Independent 

Science Advisory Panel—Final report on 

spring pulses and adaptive management: U.S. 

Institute for Environmental Conflict Resolution, Missouri River Recovery Implementation Committee, 11–STRI–1482, 58 p.

Jacobson, R.B., Annis, M.L., Colvin, M.E., 

James, D.A., Welker, T.L., and Parsley, M.J., 

2016a, Missouri River Scaphirhynchus albus

(pallid sturgeon) effects analysis—Integrative 

report 2016: U.S. Geological Survey Scientific Investigations Report 2016–5064, 154 p. 

[Also available at http://dx.doi.org/10.3133/

sir20165064.]

Jacobson, R.B., Annis, M.L., Parsley, M.J., James, 

D.A., Colvin, M.E., and Welker, T.L., 2015a, 

Science information to support Missouri River 

Scaphirhychus albus (pallid sturgeon) effects analysis: U.S. 

Geological Survey Open-File Report 2015–1226, 78 p. [Also 

available at http://dx.doi.org/10.3133/ofr20151226.]

Jacobson, R.B., Parsley, M.J., Annis, M.L., Colvin, M.E., Welker, 

T.L., and James, D.A., 2015b, Development of conceptual ecological models linking management of the Missouri River to 

pallid sturgeon population dynamics: U.S. Geological Survey 

Open-File Report 2015–1038, 47 p. [Also available at http://

dx.doi.org/10.3133/ofr20151038.]

Jacobson, R.B., Parsley, M.J., Annis, M.L., Colvin, M.E., 

Welker, T.L., and James, D.A., 2016b, Development of 

working hypotheses linking management of the Missouri 

River to population dynamics of Scaphirhynchus albus

(pallid sturgeon): U.S. Geological Survey Open-file Report 

2015–1236, 33 p. [Also available at http://dx.doi.org/10.3133/

ofr20151236.]

Murphy, D.D., and Weiland, P.S., 2011, The route to best science 

in implementation of the Endangered Species Act’s consultation mandate—The benefits of structured effects analysis: 

Environmental Management, v. 47, no. 2, p. 161–172. [Also 

available at http://dx.doi.org/10.1007/s00267-010-9597-9.]

0 0.5 1 2 MILES

0 0.5 1 2 KILOMETERS

92°58'

39°08'

39°06'

39°04'

92°56' 92°54'

EXPLANATION

212

167

Elevation, in meters 

above the North 

American Vertical 

Datum of 1988

Base data from U.S. Geological Survey digital data, 1999

Universal Transverse Mercator projection

Figure 3. Example of a 2-dimensional hydrodynamic modeling reach used in the 

Missouri River Pallid Sturgeon Effects Analysis (Jacobson and others, 2016a).

For additional information, contact:

Director, USGS, Columbia Environmental Research Center

4200 New Haven Road, Columbia, Missouri 65201

573-875-5399

Or visit the CERC Web site at: http://www.cerc.usgs.gov/

ISSN 2327-6932 (online)

http://dx.doi.org/10.3133/fs20163057