Economic
Value of
Potentially
Affected
Fisheries
Geographic
Distribution (USA):
New Zealand
Mudsnail,
(Potamopyrgus
antipodarum)
PSMFC
Funded
Projects,
Reports
Publications Links
(USGS
Fact
Sheet)
Species: New Zealand Mudsnail (Potamopyrgus antipodarum)
Photo Credit: Amy Benson, USGS
Status
Washington Administrative Code 220-12-090 classifies the New Zealand mudsnail
(NZMS) as “prohibited.” Oregon: NZMS’s are not specifically classified as
“prohibited”, “controlled”, or “non-controlled” under Oregon Administrative Rule 635056. As a result, live snails are prohibited from being possessed; imported; purchased;
sold; exchanged; or offered for sale, purchase or exchange without a state permit until
they are classified. California: Title 14, Section 671 (c) (9) of the California Code of
Regulations classifies NZMS’s as “restricted.” Therefore, it is unlawful to import,
transport, or possess live NZMS’s in the state except under permit issued by the
California Department of Fish and Game. Idaho: NZMS’s are not specifically regulated
by the state of Idaho. However, under Idaho Administrative Code 13.01.10.100, “no
person shall import, export, transport into or cause to be transported within, release or sell
Educatio
Materials
within the state of Idaho any living wildlife including wildlife eggs” without first
obtaining a permit from the Idaho Department of Fish and Game. In Montana, NZMS’s
are listed in Priority Class 2, species that are present and established in Montana and have
the potential to spread in Montana and there are limited or no know management
strategies for these species. These species can be managed through actions that involve
mitigation of impact, control of population size, and prevention of dispersal to other
water bodies (Proctor, Tina. 2004).
Synopsis
(****how much was taken from proctor********)
The NZMS is native to freshwater streams and lakes of New Zealand and adjacent small
islands; it is naturalized in Australia and Europe. Populations are wide spread in the
Western United States, as well as Lake Ontario and Superior.
Not much attention was cast on the tiny mudsnail (¼ inch in length) at the time of its
discovery in 1987 in the middle-Snake River in south-central Idaho (near Hagerman). It
was introduced into the U.S, some think, in a batch of rainbow trout eggs brought from
New Zealand or Australia. Since then it has spread into 10 states and Canada.
Unfortunately, the snail has spread to some blue ribbon trout streams across the west in
California, Montana, Colorado and Wyoming.
The North American population is only self-cloning females (triploid parthenogenetic
females); meaning a single individual can start a new population. The NZMS can form
dense colonies carpeting of the bottom. In the Madison River drainage, including
Yellowstone National Park, researchers at Montana State University reported over
750,000 mudsnails per square meter (Hall 2001) and 800,000 individuals m2 (Lucas,
1959 in Dorgelo, 1987). Research has shown mudsnails demonstrated a negative effect
on mayfly (Baetis spp.) survivorship (Cada 2004). Mudsnails have been found to deplete
the standing crop of aquatic algae and periphyton (Cada 2001; Hall 2001; Hall et al.
2003). Fish in North America, sometimes ingest mudsnails. These species include
mountain whitefish (Prosopium williamsoni), sculpin (Cottus sp.) and brown trout (Salmo
trutta) (C. Cada and B. L. Kerans, unpublished data in Proctor, 2004). These fish gain
little energy however, because studies have shown that the snails are capable of passing
through the digestive canal of trout alive and intact (Bondesen and Kaiser 1949, Haynes
et al. 1985).
New Zealand Mudsnails hitchhike the country by lodging in fishermen’s waders and
other fishing gear, closing their operculum (the trap door used to seal off their shell), and
then traveling as far as the unknowing fishermen will take them. The seriousness of this
hitchhiking problem became apparent as mudsnails began showing up in popular trout
streams hundreds of miles from the nearest mudsnail infestation. In 2001, for example,
the Owens River, a popular trout stream in the California’s Eastern Sierra, became
infested; likely caused by a fisherman’s contaminated gear. In 2004, Boulder Creek, a
trout stream near Boulder, Colorado became infested and the impact to anglers was
significant. Shortly after the infestation, the Colorado Wildlife Commission closed a
two-and-one-half mile stretch of Boulder Creek to fishing to reduce the risk of fishermen
accidentally moving exotic New Zealand mudsnails to other streams and lakes. The
NZMS was also recently found in Oregon’s Deschutes River, another popular fishing
destination.
New Zealand mudsnails are difficult to eradicate once in a stream. Research on potential
biological control methods includes the use of trematode, which shows some promise
(Emblidge and Dybdahl 2004).
Studies linking mudsnails to significant disruption to the aquatic ecosystem and
concomitant impacts to fish have yet to be documented. This may explain why funding
for mudsnail management activities is minimal when compared to other invasive species
issues such as zebra mussel prevention and ballast water management and research.
Economic Value of Fisheries Resources That Potentially Could
Be Affected by the New Zealand Mudsnail
Trout Fishing, Economic Value, Colorado (estimate): $53 value per angler
day x 7,637,000 angler days trout fishing = $404,761,000 (Figures taken from
USFWS, 2003a, USFWS, 2003b)
Chinook Salmon, State of Idaho: During the 2001 salmon season, recreational
fishing for salmon was responsible for $89,880,015 in expenditures in Idaho
(Reading 2001).
*******find another….chinook not that greaqt***********
Geographic
Distribution
(Potamopyrgus antipodarum)
(USA):
New
Zealand
Mudsnail
Source: Department of Ecology, Montana State University, Bozeman
PSMFC Funded Projects
None
Publications
Cada, Chelsea. 2004. Competitive interactions between the invasive Potamopyrgus
antipodarum and baetid mayflies: temporal variation and community-level consequences
An Annual Report to the Montana Water Center, US Geological Survey. Montana State
University—Bozeman, Bozeman, MT. 14pp c/webpage/New Zealnd MS cada 2004
imteractions.pdf] [--- button]
Hosea, Robert C. and Brian Finlayson. 2005. Controlling the spread of the New Zealand
mudsnail on wading gear. *********get correct citation*******The Resources Agency
Department Of Fish and Game Office of Spill Prevention and Response Administrative
Report 2005. New Zealand mudsnail control wading gear 2005.pdf State of California
[--- button] ***find this file*******
Links
Montana State University http://www.esg.montana.edu/aim/mollusca/nzms/index.html.
********fed gov website…nzms plan*********
Educational Materials
********New Zealand mudsnail card picture here and information on how to
order*********
References
Bondesen, P. and E. W. Kaiser. 1949. Hydrobia (Potamopyrgus) jenkinsi (Smith) in
Denmark illustrated by its ecology. Oikos 1:252-281.
Cada, Chelsea. 2001. Effects of New Zealand mudsnails on native invertebrates in
Darlington Ditch, Montana. Minutes of the First Annual Conference on New Zealand
Mudsnails in the Western USA, July 9-10, 2001. Bozeman, Montana.
Cada, Chelsea. 2004. Competitive interactions between the invasive Potamopyrgus
antipodarum and baetid mayflies: temporal variation and community-level
consequences An Annual Report to the Montana Water Center, US Geological Survey.
Montana State University—Bozeman, Bozeman, MT. 14pp
Dorgelo, J. 1987. Density fluctuations in populations (1982-1986) and biological
observations of Potamopyrgus jenkinsi in two trophically differing lakes.
Hydrobiological Bulletin 21:95-110.
Emblidge Alison and Mark Dybdahl. 2004. Third Annual Potamopyrgus antipodarum
Conference,215 Cheever Hall, Montana State University, Bozeman, MT.
Hall, R.O., J.L. Tank, and M.F. Dybdahl. 2003. Exotic snails dominate nitrogen and
carbon cycling in a highly productive stream. Frontiers in Ecology and the Environment
1:407-411.
Hall, R.O. 2001. Estimating New Zealand mudsnail impact based on consumption rates
of algae in 2 rivers in Yellowstone National Park. Montana. Minutes of the First Annual
Conference on New Zealand Mudsnails in the Western USA. Bozeman, Montana.
Haynes, Alison, B. J. R. Taylor, and M. E. Varley. 1985. The influence of the mobility
of Potamopyrgus jenkinsi (Smith, E. A.) (Prosobranchia: Hydrobiidae) on its spread.
Archives of Hydrobiologie 103:497-508.
Lucas, A. 1959. Les Hydrobia (Bythnellidae) de l’Ouest de la France. Journal of
Conchology 99:3-14.
Proctor, Tina. 2004. Management and Control Plan for the New Zealand Mudsnail
(Potamopyrgus antipodarum) DRAFT Prepared by the New Zealand Mudsnail
Management and Control Plan Workgroup August 2004. USFWS, Denver Co. 57 pp.
Reading, Don. 2001. The Economic Impact of the 2001 Salmon Season in Idaho. Ben
Johnson Associates. 6070 Hill Road Boise, Idaho 83703.
USFWS. 2003a. Net Economic Values for Wildlife Related Recreation in 2001,
Addendum to the 2001 National Survey of Fishing, Hunting and Wildlife-Associated
Recreation Report 2001-3 September 2003. 28 pp.
USFWS 2003b. 2001 National Survey of Fishing, Hunting, and Wildlife-Associated
Recreation Colorado. FHW/01-CO-Rev. 86 pp