FY07-09 proposal 200703200

Jump to Reviews and Recommendations

Section 1. Administrative

Proposal titlePotential effects of the invasive New Zealand mudsnail in tributaries of Bonneville Reservoir and the Deschutes River, (Potamopyrgus antipodarum).
Proposal ID200703200
OrganizationUS Geological Survey (USGS) - Cook
Short descriptionEvaluate the potential effects of the New Zealand mudsnail on important salmonid rearing habitats in the Columbia Gorge Subbasin
Information transferAll work will be disseminated via technical reports, peer reviewed publications, and presentations
Proposal contact person or principal investigator
Form submitter
Tim Counihan USGS tim_counihan@usgs.gov
All assigned contacts

Section 2. Locations

Province / subbasin: None Selected / None Selected

Hood River
Klickitat River
Wind River

Section 3. Focal species

primary: Anadromous Fish
secondary: Bull Trout
secondary: Rainbow Trout

Section 4. Past accomplishments


Section 5. Relationships to other projects

Funding sourceRelated IDRelated titleRelationship

Section 6. Biological objectives

Biological objectivesFull descriptionAssociated subbasin planStrategy
[BO Title left blank] New zealand mudsnails will effect important rearing habitats for juvenile salmon Columbia Gorge limit efffects of invasive species on native biota.

Section 7. Work elements (coming back to this)

Work element nameWork element titleDescriptionStart dateEnd dateEst budget
Other Work Element 1. Develop standardized survey techniques that can be used to assess the distribution of NZMS in the Deschutes River in a variety of habitats. Task 1.1. Conduct an experimental evaluation of the efficacy of different sampling techniques to survey for NZMS in representative habitats in the Deschutes River. We will sample areas with known infestations using both disturbance-based sampling equipment (i.e., Hess sampler) and passive sampling techniques (collection and examination of substrate) that examine quadrats of varying sizes. Survey design will be derived based on protocols developed by the Environmental Monitoring and Assessment Program (EMAP) of the Environmental Protection Agency (EPA). Protocols for sampling aquatic macroinvertebrate communities will be derived from methods developed under the National Water-Quality and Assessment (NAWQA) Program developed by the USGS. We will begin by deploying these sampling techniques in areas known to be colonized (i.e., Heritage Landing, Deschutes River State Park, Deschutes River; Wapinita Access Point, Deschutes River, Maupin). Our intent is to over sample areas with known infestations so that we will be able to estimate the statistical properties of the resultant frequency distributions (see below). We will use the power curves provided in, Green and Young (1993), as a guideline for the initial sampling effort required. New Zealand mudsnails will be narcotized before fixing. After collection we will hold the NZMS in a clean container supplied with river water. Menthol crystals will then be added to the container. When the animals do not respond to touching, most of the water will be carefully removed and replaced with 10% buffered formalin or Kahle's or Bouin's fluid. DNA samples will also be collected. DNA samples will be obtained by placing a few snails directly into 90-100% ethanol. Task 1.2. Provide an evaluation that will assess the level of sampling intensity necessary to detect varying densities of NZMS in a variety of habitat types in the Deschutes River. After the samples are collected and processed, modeling and statistical simulation techniques will be used to determine the best plot size and level of sampling effort to characterize populations of different densities, including densities that will facilitate early detection of this invasive snail. For each habitat and substrate type sampled, we will estimate densities of NZMS, characterize the frequency distribution, estimate the sample variance and mean, estimate the negative binomial parameter k and a chi-square test of the equality of the variance and mean by gear type (Ho: Poisson distribution; Elliot 1977). An analysis of covariance will be conducted with 1/k (an index of patchiness) as the dependent variable. Habitat type and gear will be predictor variables; the covariate will be the rank of mean density, m (as per Green and Young. 1993). We will estimate the distribution of the ratio of m/k and provide an assessment of the applicability of the power curves provided in Green and Young (1993) to the sampling of NZMS in the Deschutes River. 1/1/2007 12/31/2007 $216,670
Biological objectives
Other Work Element 2. Apply survey techniques developed in Work Element 1 to assess the presence or absence of the NZMS at popular access points and in important rearing and migratory areas in the Deschutes, Klickitat, Hood, and Wind rivers. Task 2.1. Determine site selection in areas upstream and downstream of popular access points and important rearing and migratory areas in the Deschutes, Klickitat, Hood, and Wind rivers. We will consult with local entities to identify popular access points to be sampled. Similarly, we will consult with pertinent fish biologists for the ODFW, Yakama Nation, Fish and Wildlife Service, The Confederated Tribes of Warm Springs and the USGS to develop a list of candidate important rearing habitats to be sampled. Task 2.2. Implement the detection-monitoring program. After we have completed the statistical analysis of samples collected in habitats adjacent to Heritage Landing, and Wapinita Access Point on the Deschutes River, we will implement the survey design at popular access points on the Deschutes, Klickitat, Hood, and Wind rivers. Sample site selection procedures at the access points will be conducted using EMAP protocols. 1/1/2008 12/31/2008 $126,788
Biological objectives
Other Work element 3. Determine isotopic signatures of representative trophic levels in the Deschutes, Klickitat, Hood, and Wind rivers in sampling areas with and without NZMS to assess the effects of the NZMS to food webs. Given the potential for the NZMS to dominate invertebrate communities after introduction, it seems reasonable to assume that a concomitant restructuring of the energetic pathways that culminate in food for anadromous and resident salmonids will occur (Hall et al. 2003 and 2006). Understanding the nature of the alterations to the structure of the food web in areas with known infestations and understanding the potential effects of the introduction of the NZMS in areas yet to be colonized will allow fish managers to assess how and where to direct their efforts at prevention. For instance, if the analyses conducted in this study indicate that certain streams are not likely to be significantly colonized or that the energetic pathways affected will not result in a significant loss in prey items for target fisheries, efforts at prevention can then be directed to areas that are most likely to be affected. Task 3.1. Sample processing for isotopes Detrital, macroinvertebrate and periphyton samples will be collected and analyzed for stable isotopes. Primary, and secondary production will also be assessed as well as insect gut contents to further examine and corroborate what aquatic invertebrates are consuming (e.g detritus, filamentous algae, diatoms). We also propose to collect juvenile anadromous salmonids and/or resident trout using electrofishing, traps, hook-and-line sampling, trap netting, or other methods. We will coordinate intensively with other projects currently collecting fish in the target streams to obtain tissue samples for analysis. Dorsal muscle samples from fish larger than 67 mm total length will be collected. For smaller fish (less than 67 mm), whole fish will be collected to assure a large enough sample (Saito et al. 2001). Stomach samples may also be taken to corroborate what fish are eating. Task 3.2. Establish food web linkages. Simple mixing models are limited by the number of sources and tracers used therefore they do not adequately describe complex food webs having multiple contributing sources and pathways (Lubetkin and Simenstad 2004). We propose to use a similar approach as that of Lubetkin and Simenstad (2004) that use companion models SOURCE and STEP that overcome these limitations and can model complex food webs in aquatic ecosystems. Task 3.3. Determine direct links between consumers and their diets The STEP model is used to determine links between consumers and their diets. This model estimates the isotopic signature for each consumer as a composite of its diet modified by one metabolic fractionation. Task 3.4. Validate food web model. Model validation will be done in a similar manner to Lubetkin and Simenstad (2004) where simulations will be run on data assumed to be perfect (no variability) and data assumed to be more representative of multiple samples (introduced variability). By performing these simulations we can evaluate how the model performs under ideal conditions, focusing on the mathematical validity of the model and how natural variability in the data would affect the model’s performances. Results may also be compared to other simple mixing models. 1/1/2008 12/31/2008 $220,959
Biological objectives
Other Work Element 4. Bioenergetics modeling on juvenile salmonids assessing impacts to growth due to NZMS colonization The colonization of a salmon rearing or migratory area with NZMS has the ability to alter feeding patterns by juvenile salmonids through shifts in invertebrate community dynamics. Kerans et al. (2005) observed that high densities of NZMS were associated with low colonization of other macroinvertebrates, and could have the potential to influence large-scale distribution of macroinvertebrates. Furthermore, NZMS were observed to be responsible for 65-92% of total invertebrate production in three Yellowstone rivers, this strongly indicates altered invertebrate assemblages and/or ecosystem function (Hall et al. 2003). We will use a bioenergetics model to estimate growth rate potential for juvenile salmonids in rearing and migratory areas to assess potential impact to growth rate given a community shift in primary and secondary production from an invasion of NZMS. The Fish Bioenergetics model 3.0 (Hanson et al. 1997) is a dynamic fish energy budget that follows the principle that energy input (consumption) and outputs (respiration, waste, and growth) must balance. This equation is typically expanded to the generalized form proposed by Warren and Davis (1967): C = (Mr + Ma + SDA) + (F + U) + (Gs + Gr) (metabolism) (waste) (growth) C = rate of energy consumption, Mr = standard metabolic rate, Ma = metabolic rate increase (above the standard rate) due to activity, SDA = metabolic rate increase due to specific dynamic action, F + U = waste losses due to egestion (feces) and excretion (urine) rates, Gs = somatic growth rate due to protein synthesis and lipid deposition, and Gr = growth rate due to gonad (reproductive) synthesis. We can use the model to predict growth over time, accounting for temperature, fish size, and diet quality. Bioenergetics models have been widely used and many of the parameters for individual species can be obtained from the literature (Hanson et al. 1997, Beauchamp et al. 1995, Beauchamp et al. 1989). Juvenile salmonid growth and recruitment success is likely influenced by the availability and quality of prey items. If existing rearing areas are dominated by NZMS, shifting the macroinvertebrate prey availability, juvenile salmon will likely be forced to find other suitable habitat areas. Task 4.1. Determine the energy density of NZMS and other macroinvertebrates as prey items for salmonids Literature stated values for NZMS were determined to be 6000 J g super(-1) (McCarter 1986). However, unless the shell is broken NZMS can pass through the gut alive and add little to no nutritional value. Many other prey energy densities have been determined throughout the literature (Hanson et al. 1997). When possible we will collect dominant prey items (sampling described in work element 2) to determine their energy content within the geographic area of interest to be used in our model. Task 4.2. Use juvenile salmon diet information and the bioenergetics model to examine growth rate/potential in rearing, overwintering and migratory habitats Diet information will be obtained through literature review and isotope and gut analysis from samples obtained in the field. A small number of lethal fish samples (collection described in task 3.1) will be taken to corroborate diet information. Non-lethal fish samples for length and weight will also be obtained periodically throughout the study period to obtain growth estimates. Task 4.3. Use the bioenergetics model to estimate the growth rate/potential given a shift in the macroinvertebrate community dominated by NZMS in rearing, overwintering, and migratory habitats. We hypothesize a shift in the invertebrate community due to dominance of NZMS consuming the majority of available primary production and displacing native secondary producers. We will perform a series of model simulations manipulating the proportion of diet of native and non-native invertebrates (NZMS) consumed by juvenile salmonids. Our model simulations will be based on different density estimates of proportions of native/non-native invertebrates available for consumption. 1/1/2009 12/31/2009 $184,925
Biological objectives

Section 8. Budgets

Itemized estimated budget
Supplies [blank] $5,000 $15,000 $0
Other Lab Processing Fee (Isotopes) $13,320 $39,960 $0
Travel [blank] $5,100 $5,100 $3,600
Personnel [blank] $151,210 $164,036 $127,038
Overhead [blank] $72,566 $93,125 $54,287
Totals $247,195 $317,221 $184,924
Total estimated FY 2007-2009 budgets
Total itemized budget: $749,340
Total work element budget: $749,342
Cost sharing
Funding source/orgItem or service providedFY 07 est value ($)FY 08 est value ($)FY 09 est value ($)Cash or in-kind?Status
Totals $0 $0 $0

Section 9. Project future

FY 2010 estimated budget: $0
FY 2011 estimated budget: $0

Future O&M costs:

Termination date:
Comments: project will be completed in the three year period.

Final deliverables: technical report, publications and presnetations

Section 10. Narrative and other documents

200703200_revised_7_14_2006 Jul 2006
Response to comments on proposal 200703200 Jul 2006

Reviews and recommendations

FY07 budget FY08 budget FY09 budget Total budget Type Category Recommendation
NPCC FINAL FUNDING RECOMMENDATIONS (Oct 23, 2006) [full Council recs]
$23,333 $23,333 $23,333 $69,999 Expense ProvinceExpense Fund
NPCC DRAFT FUNDING RECOMMENDATIONS (Sep 15, 2006) [full Council recs]
$23,333 $23,333 $23,333 $0 ProvinceExpense
Comments: BPA preliminary in lieu determination


Recommendation: Response requested

NPCC comments: This proposal gives an adequate review of why this invasive snail (New Zealand Mud Snail) should be investigated in the subbasin but the program proposed is more suitable for basic research. The work could be important for characterizing the distribution and abundance of the invasive snail, examining its impact on primary production, and determining habitat parameters affecting its spread. However, the ISRP requests that project sponsors respond to the following issues: 1. The proponents have underestimated the task of determining the effect of the mud snail on the ecosystem supporting juvenile salmonids in the Columbia Gorge Subbasin. Even if the snail does consume a major proportion of primary production, if its abundance is negatively correlated with fish food abundance, or if it is found to be fish food species, the significance of these findings for survival of juvenile salmonids is not clear. The proposal would be improved by an explanation of how these data would help determine ecological effects of the mud snail at the secondary and tertiary (fish) trophic level. What would the form of the "logistic" model proposed be? 2. It would be helpful if the proponents described the potential management actions if the mud snail was found to be affecting salmon production.

ISRP FINAL REVIEW (Aug 31, 2006)

Recommendation: Fundable

NPCC comments: The sponsors have adequately responded to the ISRP's concerns about potential ecosystem effects and management options, and the project is now fundable. The ecosystem effects seen elsewhere warrant the tasks to determine distribution in the Columbia Gorge tributaries. The added tasks will quantitatively place the colonization of these tributaries by the New Zealand Mud Snail in an ecosystem context (both taxonomically and energetically). Much background information was presented on the species, and many useful data will be gathered during this study. The sponsors addressed ISRP’s concern about management actions although halting the spread of the New Zealand Mud Snail will be a major challenge even when better information is available. The data to be collected and the analyses seem to fit together quite well. The monitoring and surveillance proposed will assist control and mitigation planning for this invasive species. The bioenergetic model proposed to evaluate the response by juvenile salmonids to high densities of the snail is a useful tool. However, the sponsors will need to consider the possibility that salmonids may not eat snails; they might shift to a diet dominated by other invertebrates. It will be important to directly observe what the fish are eating. Stable isotope analyses may not be sufficient. There are very few records in the literature of juvenile salmonids eating shelled gastropods. The sponsors should make sure their project will not inadvertently lead to further spread of the mud snails in the Columbia River Basin via contaminated equipment, boats, etc.