Database Update Archive

  1. The database was updated on 2007 Mar 05. Val Brenneis added 8 records from 2006 that extend the range in some known positive areas (Deschutes River, Umpqua River, Putah Creek and the Wallooskee River), and provided some density data in the comments. The on-line database now contains 1478 collection records.
  2. The database was updated on 2007 Jan 21. Dan Gustafson added added a sample from the Lower Swan River in Montana. A single snail was collected by MT DEQ in August 2003, but not recognized until sent to Dan Gustafson in Jan 2007. It represents the first record in Montana west of the continental divide. This introduction appeared to have failed and the collection was removed from the database on Sept 18, 2007.
  3. The database was last updated on 2006 NOV 06. Nick Nisson added samples from Segunda Descheca Creek and Trabuco Creek in the Aliso-San Onofre HUC. These represent a southward expansion in coastal California, not so far from Mexico.
  4. The database was updated on 2006 JUNE 15. Robyn Draheim added a new sample farther upstream in the Deschutes River of Oregon. Cindy Meyers added a sample from Hanson Slough (coastal Oregon).
  5. The database was updated on 2006 JUNE 15. Mark Abramson added 5 records from the Santa Monica Bay area of California. This is the first report in this HUC, but the 5 dispersed sites indicate the snail has been in the area for some time.
  6. The database was updated on 2006 JUNE 04. Dan Gustafson collected a moderate number of nzms from the Ruby River (Montana) below the Reservoir. There are also reports of this snail above the reservoir, but below Warm Springs Creek, but high water prevented confirmation there. This is the first report in this HUC, but both sites have long been predicted by Dan Gustafson as high risk, based on the community similarity to other positive nzms sites.
  7. The database was updated on 2006 MAR 02. Robyn Draheim added 2 collections from the lower Coos drainage in Oregon. This is the first report in this coastal HUC. The coastal area seems to be an area of active range expansion. The on-line database now contains 1459 collection records.
  8. The database was updated on 2006 FEB 6. Dawne Becker added a recent collection by Colleen Martin from Piru Creek below Pyramid Dam. This is the first record from the Santa Clara HUC and the first for the entire Southern California coastal subregion!
  9. The database was updated on 2006 JAN 24. Michael Chi-Chang Liu entered the first record from Coffenbury Lake in the alreadly positive Lower Lower Columbia, Oregon.
  10. The database was updated on 2005 DEC 28. Dan Gustafson entered 1 new collection from the lower Bruneau River in Idaho. This is the first record in this HUC even though it joins the long positive reach of the Snake River. The very small number of mostly dead snails were not noticed until a large sample was processed in the lab.
  11. The database was updated on 2005 NOV 24. Dan Gustafson entered 12 new collections from Idaho. There were no significant new locations even though many new areas were sampled. For what it is worth, 7.2% of all his samples from June, July and August 2005 contained mudsnails.
  12. The database was updated on 2005 OCT 25. Robyn Draheim added yet another collection in the middle Snake River in Idaho.
  13. The database was updated on 2005 OCT 07. Robyn Draheim added 2 locations in the lower Deschutes River in Oregon. These are first records from this important recreational river. The mudsnail populations are not high, but they already occupy a considerable length of the river. See the Statesman Journal press release form more information.
  14. The database was updated on 2005 AUG 29. Eileen Ryce added 2 more sites on the Bighorn River in Montana. The snails are spreading downstream, but they are not reaching high density here. Chi-Chang Liu added the first record from the Umpqua River in Oregon. The snails were very abundant, but did not extend too far upstream or downstream.
  15. The database was updated on 2005 AUG 12. Eileen Ryce added 1 site above and 2 sites below the known site on the Missouri River at Wolf Creek Bridge (Montana). Several other sites in the area remain negative and population sizes remain low. Note: Dan Gustafson miscoded one of the Wolf Creek Bridge collections as having abundant snails where they were only very sparse. This was corrected today also.
  16. The database was updated on 2005 AUG 09. Dawne Becker added a collection by Debra Hawk from Rush Creek California. This is the first record in the Mono Lake HUC. Robyn Draheim added 5 more records from coastal Oregon.
  17. The database was updated on 2005 JULY 26. Robyn Draheim added 2 early collections from the lower Rogue River in Oregon. Note- the oldest collection records are important to get a better picture of the spread. Dan Gustafson also added 11 samples from the Snake River drainage, but nothing new.
  18. The database was updated on 2005 JULY 12. Robyn Draheim added a site on the lower Rogue River in Oregon. This adds yet another HUC to the snails range. Snail dispersal between rivers along the Pacific coast seems to be indicated.
  19. The database was updated on 2005 JUNE 09. Eileen Ryce added 4 more sites on the Madison River, Montana.
  20. The database was updated on 2005 MAY 20. Eileen Ryce added another site in the lower Madison River, Montana. The invading snail has remained at only "sparse" levels in this area of the river for at least 3 years.
  21. The database was updated on 2005 APR 06. Pat Clancey reports O'Dell Creek in the Madison River, Montana has abundant mudsnails present. This is the first report in mid-river area of the drainage. The snail has been in the upper river and the lower river areas for some time now.
  22. The database was updated on 2005 APR 06. Lawrence Gray added 2 more Utah collections.
  23. The database was updated on 2005 Feb 12. Robin Knox provided a real collection record from the Boulder Creek population in Colorado, so the the dubbed record for this site was removed (the dubbed location was very close!) Jessica DelMonte added 2 locations in the Portneuf River drainage of Idaho.
  24. The database was last updated on 2005 JAN 25. Robyn Draheim reported a collection from lower Bully Creek of the Malheur River in Oregon. The snails were collected (30 - 40) in a water sample in a bucket lowered from a bridge! The snails are likely quite abundant as this is normally not a great way to collect benthic organisms!
  25. The database was last updated on 2004 MAY 07. Mark Vinson added the Jordan River in Utah and Sweetwater Creek in northern Idaho. Sweetwater Creek is a tributary to the lower Clearwater River and this is the first record in that drainage. The on-line database now contains 1390 collection records.
  26. The database was updated on 2004 JAN 29. James Navicky added the Lower Calaveras R. & Morman Slough. This is the third record in the Central Valley of California.
  27. The database was updated on 2004 JAN 29. Michelle Workman added Lower Mokelumne River. This is the second record in the Central Valley of California.
  28. The database was updated on 2003 DEC 22. Mark Vinson added Kays Creek Pond in Utah and Dan Gustafson added a repeat sample on the Owyhee River The on-line database now contains 1388 collection records.
  29. The database was updated on 2003 NOV 22. Susan Ellis added a location on Califoria's Putah Creek. This represents a major range jump in California. See www.wildlifefiles.com/Putah.html for more information.
  30. The database was updated on 2003 OCT 31. Mark Vinson added 9 records filling the range in the upper Green River and the Great Salt Lake drainage.
  31. The database was updated on 2003 OCT 13 (20 records were added since 2003 April 19). New sites include Silver Creek in Idaho, Big Sheep Creek in Montana, the Bighorn River below Boysen Reservoir in Wyoming and several tailwater rivers in Utah.
  32. 2002 SEP 14. Dan Gustafson discovered moderate numbers of mudsnails in the Bighorn River right below the Yellowtail afterbay Dam, a very popular tailwater trout fishery. This represents another substantial jump from other known populations. The snails do not appear to extend far downstream at this time.
  33. 2002 JULY 16. Dick Oswald finds abundant mudsnails in the Beaverhead River below Clark Canyon Dam. This is a significant jump from other Montana or Idaho populations. The introduction must have been some time earlier based on the number of snails.
  34. 2002 JUNE 15. The Blue Ribbon Missouri River is occupied. Dan Gustafson found small numbers of the snails at the Wolf Creek Bridge Fishing access site. This represents a big jump downstream from other known sites in the Madison River Drainage. This is likely an early detection.
  35. 2002 MAR 26. Mark Anderson reports that the Glen Canyon tailwater area on the Colorado River already has abundant mudsnails. In April, Sorensen & Nelson found mudsnails distributed over 225 miles downstream of Glen Canyon, including the Grand Canyon area. The introduction date here is likely several years earlier.
  36. 2002 MAR 18. Dave Richards verified that the lower Madison River near Norris Bridge has small numbers of mudsnails present.
  37. 2001 SEP 18. Mark Vinson reports low numbers in the Green River downstream of Flaming Gorge Reservoir. This represent a giant jump from either the Snake or lower Colorado Rivers.
  38. 2001 AUG 26. Dan Gustafson verified that DePuys Spring Creek on the Yellowstone River has abundant mudsnails present. While this might seem like a jump downstream from the Gardner River, the new presence of Vorticifex indicates a transfer from the Snake River.
  39. 2001 APR 28. Dawne Becker reports the Owens River in California is occupied. This represents a giant jump from either the Snake or Colorado Rivers.
  40. 2001 APR 27. Dan Gustafson discovers a single nzms in Kalispell Creek, a tributary of Priest Lake. A population here needs to be confirmed, but if present, this represents major jump to the north.
  41. 2000 SEP 1. Dan Gustafson discovers a sparce population in the Buffalo River at the US-20 Bridge. This is the first sighting in the Henrys Fork drainage, which has had mudsnails nearby for many years. This is likely an early detection.
  42. 2000 APR 30. Dan Gustafson discovers a large population present in the lower Pahsimeroi River. This population seems to be associated with the hatchery and represents a sizeable jump from the Snake River.
2002 JUNE 18, updated on 2007 JAN 21