Dr. Rob Dillon, Coordinator

Monday, November 18, 2002

FMCS Meeting 3/03

The 2003 symposium of the Freshwater Mollusk Conservation Society is scheduled for March 16 - 19 at the Sheraton Imperial Hotel in Research Triangle Park, Durham, NC. The theme will be "Connections . . . A Focus on Habitat Conservation." John Alderman will be our host (aldermjm@mindspring.com).

If this third biennial symposium of the FMCS is anything like its predecessors in Chattanooga and Pittsburgh, registrants are sure to enjoy excellent papers, super social events, and great fellowship with comrades on the front line of mollusk conservation. There will be a meeting of the Gastropod Committee, probably on the 19th. Registration forms, details regarding accommodations, and a call for papers can be found at [link removed].

Note the following deadlines:
  • November 30 - Submission of abstracts.
  • December 6 - Applications for student travel awards.
  • December 15 - Early Registration.
  • February 28 - Hotel reservations.
Hope to see you all there!

Wednesday, September 11, 2002

Report from Charleston

I'm pleased to report that freshwater gastropodswere the marquee attraction at the 68th meeting of the American Malacological Society in Charleston last month. The scientific sessions commenced Sunday morning August 4 with a pair of plenary addresses on our favorite animals: Amy Wethington reminding us what marvelous models freshwater snails may be to address scientific questions of great generality, and Ken Brown & Paul Johnson highlighting their presently imperiled status.

These talks segued smoothly into the featured symposium of AMS 2002: "The Biology and Conservation of Freshwater Gastropods," a program of 15 talks ranging broadly across the ecology, evolution, and genetics of snails from Alberta to Zambia. Speakers included John Alderman, Art Bogan, Rob Guralnick, Matthias Glaubrecht, Steve Johnson, Eileen Jokinen, Chuck Lydeard, Bob McMahon, Doug Shelton, Jon Todd, Tim Stewart, Brian Watson, and others. The symposium was designed to build toward a meeting of the Freshwater Gastropods of North America project Sunday evening.

Minutes of that eventful gathering are appended below. If those of you who were present notice any additions or corrections to these minutes, please let me know. The bottom line from the Sunday evening meeting can be summed up in one word, however - decentralization.

The celebration of freshwater gastropods continued through AMS conference. There were seven contributed talks and ten poster presentations on freshwater snails Monday afternoon. And Tuesday August 6 featured a special session, organized by Amy Wethington, entitled "Pulmonates in the Laboratory." The eight invited presentations primarily involved Physa and Biomphalaria and focused on behavioral, morphological, and genetic questions.

A good time was had by all. For more details, the Program and Abstracts of all presentations at the Charleston meeting should be available soon as a PDF file from the AMS website:

Plans are currently in the works for a special issue of the American Malacological Bulletin featuring the freshwater gastropod talks given at AMS 2002. So keep in touch, everybody!

----[Minutes of the FWGNA Meeting 4Aug02]-----
Lightsey Conference Center, College of Charleston

Attending: Brian Watson, John Alderman, Jacquie Lee, William S. Rabert, Matthew Campbell, David Campbell, Lyle Campbell, Sarah Campbell, Kevin Cummings, Tom Watters, Scott Martin, Gary Rosenburg, Tom McCarthy, Beth Davis, Susan Bandoni Muench, Thomas Smith, Joseph Hartman, Eugene P. Keferl, Kathryn “Ellie” Sukkestad, Ken Brown, Andy Turner, Tim Stewart, Jay Cordeiro, Bob McMahon, Chuck Lydeard, Amy Wethington (Secretary).

Meeting convened at 7:00 pm by R. T. Dillon, chair.

The meeting opened with a presentation by Jay Cordeiro of NatureServe. NatureServe employs ecologists and contract specialists to identify, preserve, and protect biodiversity. All 50 states of the U.S., 10 Canadian provinces, and 12 LAC countries have agreed to share data. It maintains the “heritage status” (rarity and richness data) for an extensive list of organisms from the United States and Canada, with which it identifies potentially imperiled species and biodiversity “hot spots.” Its web site (www.natureserve.org ) features a database “Explorer” which is a rapid and easy tool for retrieving conservation information.

Discussion followed regarding the method by which heritage ranks may be revised or updated. There are a variety of different systems to convey conservation status. Heritage ranks are controlled by the states and can be different from global ranks if states disagree. NatureServe may list two rankings if there is a difference between a Heritage Rank and a Global Rank. The best way bring about a revision would be to contact states through their relevant offices directly.

There were questions regarding the reliability of the database upon which heritage ranks rest. The NatureServe data are based on published reports and museum records, which admittedly may be old and incomplete. NatureServe updates its information three times a year from each State’s Heritage data. But without question, new data on all species are welcome at any time. There is a mechanism on the website for the public to submit information directly to NatureServe. Regarding nomenclatural standards, usually a standardized source is used, such as Turgeon et al.

The chair thanked Jay for his contribution and moved to a slide presentation reviewing the history of the FWGNA project. Landmark dates have included the 7/98 establishment of the project at the World Congress of Malacology in Washington, the 11/98 formation of a gastropod committee within the Freshwater Mollusk Conservation Society, the 3/99 second meeting in Chattanooga, and the 3/01 third meeting in Pittsburgh. Some detail was offered regarding the NSF proposals of 11/99 and 11/00, which involved a large number of collaborators, and which ultimately were less than successful.

The large, centralized effort has proven difficult to jumpstart. Meanwhile, the symposium just completed has featured reports regarding successful local freshwater gastropod surveys ongoing in Virginia, North Carolina, South Carolina, and Mississippi.

These considerations led the chair to offer a New Model for the FWGNA project. The talking points were as follows. (1) The effort should be decentralized. (2) Politically boundaries do matter. (3) Modern data are critical. (4) Local funding sources are important. (5) Central coordination should be at the database level.

The chair suggested that regionally-based individuals and small teams might be best positioned to conduct our inventory of the North American freshwater gastropods. Regional efforts might involve reviews of previously published reports, museum records, and state agency data, as well as the design of new surveys. State and regional funding should be sought, voucher specimens (in ethanol) deposited locally, and reports designed primarily to suit the needs of the resource agencies focused on particular watersheds and political boundaries. But in conjunction with these decentralized efforts, workers might send their databases in some standard format to a central office. And the central office might both coordinate with NatureServe, and (ultimately) compile a guidebook to the freshwater gastropods at the continental level.

Regarding identification problems, each worker should simply do his best with the references currently available. As long as voucher specimens are deposited in publicly available collections, any errors can ultimately be remedied.

The projected guidebook to the freshwater snails of North America should have nice illustrations and be easy to use. Since this work would not be intended as a scientific monograph, distribution maps might be offered at the continental scale and show only low resolution. The work would be multiauthored, including anyone with a significant contribution of data, with proceeds from the sale going to the FMCS.

A lively discussion followed the chair’s presentation. There was debate regarding whether the projected guidebook should feature broad ranges or more precise dots. Although dot-maps are certainly more helpful for management, concern was expressed that endangered species might become vulnerable to overcollection. Perhaps our mapping units should be HUCs, or counties, or dots 20 miles wide. It was suggested that detailed data might be reserved for the agencies, which could then regulate its dissemination. Amateur collectors are not the enemy, however.

There was also discussion regarding funding sources. In the last couple years, federal and state support for biotic surveys has become more difficult to obtain. One option is to design surveys that involve specialists in all freshwater taxa, not simply the gastropods. J. Alderman suggested a “King’s Challenge” mechanism, where large private benefactors might be interested in biodiversity surveys.

Noting the lateness of the hour (8:30 pm) the Chair turned the floor over to Gary Rosenberg (AMS Systematics Committee), for a review and discussion of database standards in systematic collections. As he did so, he made this final plea:

Any worker willing to survey his local freshwater gastropod fauna is encouraged to email Rob Dillon. Then do it! Don’t make me come over there.

Thursday, July 11, 2002

Physa progress

F. C. Baker called Physa heterostropha “the most misunderstood mollusk in America.” Without question, the entire family Physidae has been a source of considerable frustration to me personally, since I collected my first batch as a child 30-40 years ago. The doggone things are everywhere, and all 40+ nominal species of American Physa pretty much look identical.

Now I’m happy to report that progress is being made. In the most recent issue of Invertebrate Biology, Amy Wethington, two undergraduates and I report that the most common species of Physa in North America is Physa acuta. Here’s the reference:

Dillon, R.T. Jr., A.R. Wethington, J.M. Rhett & T.P. Smith (2002) Populations of the European freshwater pulmonate Physa acuta are not reproductively isolated from American Physa heterostropha or Physa integra. Invert. Biol. 121:226-234. [PDF]

Yes, it appears that the most misunderstood mollusk in America, together with its more northern cognate, is not different from a Physa discovered in southern France in 1805 - a Physa which has since spread throughout the Old World, down to South Africa and out to Japan. Although it seems fairly clear that Physa acuta is a North American native, it was apparently first described in Europe. I think P. acuta may be the most common freshwater mollusk in the world.

This is the but the first salvo in an all-out frontal assault on the bastion of the Physidae. This spring Chuck Lydeard, Ellen Strong and I have been awarded a $400k three-year grant from the NSF to review the systematics of the entire family. Chuck and Amy will focus on a big sequencing effort, Ellen will work on the anatomy, and I’ll keep cranking out the breeding studies.

We’ve already collected almost a year of data on crosses involving the other major group of physids, those that Burch puts in the subgenus Physella. (Physa acuta, integra, and heterostropha are in the subgenus Costatella.) We’ve got good results from Physa gyrina gyrina, Physa gyrina aurea, Physa microstriata, Physa utahensis, and a population from Zion National Park. We’ve also piddled with Physa parkeri and Physa ancillaria in the past year. Just this spring we’ve begun new experiments with the Costatella group, including Physa virgata and P. hendersoni. You’ll hear more about all this research in Charleston next month.

So what’s the bottom line? The number of biological species of physids has probably been overestimated by an order-of-magnitude. The critters show tremendous phenotypic plasticity, in shell, life history, and any other respect you could name. The Charleston meeting will feature several talks focusing on phenotypic plasticity in pulmonate snails as well. We’ll keep you posted as this research progresses.

P.S. - You will notice that we do not use “Physella” as a genus. Jack Burch (1992) has moved Physella back down to subgenus rank, and we agree. See Burch & Jung’s “Freshwater Snails of the University of Michigan Biological Station Area” (Walkerana 6:85) for more.

Friday, June 21, 2002

Freshwater Gastropod Pests, Continued...

My 5/23 message on the subject of pest snails brought an interesting response from David Richards, research ecologist with EcoAnalysts Inc and Ph.D. student at Montana State. He called my attention to a really impressive Potamopyrgus web site being developed at MSU - Bozeman. The site is "70% ready for public use" according to David (as of late May), but many of the resources are already spectacular. Check out the "Mudsnail Maps" at: http://www.esg.montana.edu/aim/mollusca/nzms/

Potamopyrgus antipodarium is not, alas, on the draft list of pest gastropods currently being circulated by Rob Cowie, the AMS Conservation chair. You may recall the allusion I made last month to a collaboration between the USDA and the AMS aimed at identifying "America's Least Wanted Mollusks." Not only is it difficult to document an economic impact for Potamopyrgus, it's also probably too late to do much about it.

But there are certainly many other pest gastropods whose introduction to North America may yet be prevented, including a couple freshwater groups. The message from Rob Cowie appended below is self-explanatory. Please consider responding to him. Or meet him, and the rest of the Pest Mollusk Committee, and David Richards, here at AMS 2002 in August!

--------- [Begin message from cowie@hawaii.edu] ---------

To all Researchers interested in the impacts of alien species:

I am sending this message out in the hope of getting feedback from people not only in the USA, but also from throughout the world.

The United States Department of Agriculture (USDA) has asked me (through the American Malacological Society) to create a list of 15 non-marine molluscan taxa that the USA should consider of paramount quarantine importance. That is, these are taxa either not yet in the USA or if they are in the USA they are confined, as yet, to only a few localities where it may be possible to eradicate them or at least to prevent them from spreading further afield. The list will eventually be accompanied by "factsheets" on each taxon in an American Malacological Society report to the USDA*.

The first step is to create the list. Working together, David Robinson, Rob Dillon and I (with Jim Smith of USDA providing guidance) have come up with the following list. We decided it was not possible to come up with just 15 species (the initial USDA request), so we have come up with groups of species belonging to 15 families. These taxa were selected based on 13 criteria that in general are thought to correlate with potential invasiveness. These criteria include biological features of the taxa (e.g., reproductive rate, body size) as well as features reflecting their interaction with humans (e.g., pest status elsewhere, frequency of interception by quarantine officials). Our method of scoring each taxon against the criteria is as yet very rudimentary.

I would very much welcome comments about this list, especially regarding any glaring omissions of taxa that you know to be serious invasive pests elsewhere in the world? [But remember, there are many pest species that are not on this list because they are already widespread in the USA.] Here's the list, with the most important taxa first:
  • Veronicellidae - especially Sarasinula plebeia and Veronicella cubensis, but also Laevicaulis alte and Diplosolenoides occidentalis. Agricultural pests.
  • Ampullariidae - especially Pomacea species (except Pomacea bridgesii), but also Pila species and Marisa species. Rice (and other aquatic plant) pests, and likely environmental pests damaging native aquatic vegetation.
  • Helicidae - especially Theba pisana and Eobania vermiculata, but also Cantareus apertus, Otala punctata, and perhaps Helix species (remember Helix aspersa - or whatever genus you consider it to be in now - is already widespread in the USA). Agricultural and garden pests.
  • Achatinidae - especially Achatina fulica, but also Archachatina marginata, and perhaps Achatina achatina. Agricultural and garden pests and general nuisances; also, as with many snail species on this list, can vector serious human parasites.
  • Hygromiidae - especially Cernuella species, Cochlicella species, and Xerolenta obvia. Agricultural pests.
  • Planorbidae - especially Indoplanorbis exustus, and to a lesser extent Biomphalaria species. Vectors of animal schistosomes not yet in the USA.
  • Milacidae - Tandonia budapestensis and Tandonia sowerbyi, and to a lesser extent, T. rustica. Crop pests.
  • Enidae - various species. Vectors of livestock diseases.
  • Succineidae - Succinea tenella/horticola, possibly also non-US Calcisuccinea species. Agricultural/horticultural pests. Contaminants of horticultural products.
  • Pleurodontidae - Zachrysia provisoria. Agricultural pest.
  • Helicarionidae - Ovachlamys fulgens and Parmarion martensi. Pest potential not fully appreciated, but contaminants of horticultural products and spreading very rapidly around the world.
  • Arionidae - Arion lusitanicus. Agricultural pest, general nuisance.
  • Urocyclidae - Elisolimax flavescens.
  • Bradybaenidae - Acusta touranensis.
  • Spiraxidae - Euglandina species (except E. rosea, which is native to the south-east USA). Predators of native snails.
Many thanks for any input you care to offer. Your help will be duly acknowledged in the final product.

Robert Cowie
Center for Conservation Research and Training
University of Hawaii
3050 Maile Way,
Gilmore 408
Honolulu, Hawaii 96822 USA

*Historical Note:
The paper for which this survey was compiled in 2002 was ultimately published in 2009:

Cowie, R. H., R. T. Dillon, D. G. Robinson and J. W. Smith (2009) Alien non-marine snails and slugs of priority quarantine importance in the United States: A preliminary risk assessment. American Malacological Bulletin. 27: 113-132. [PDF]

Thursday, May 23, 2002

Freshwater Gastropod Pests

As this year's president of the AMS, I've become involved with a USDA initiative to identify mollusks (of all sorts) that have the potential to become pests*. Although most of the critters falling into this category are land snails and slugs, occasionally freshwater gastropods receive some attention.

The following news item was called to my attention by Jim Smith, a scientist at in the USDA's Animal and Plant Health Inspection Service whom I've recently had the pleasure to work with. It comes from a web site that's new to me - NAPPO, the North American Plant Protection Organization. http://www.pestalert.org/pestnews.cfm
Subject: Mollusk from New Zealand expands range in US
Date posted: 04/23/02
Source: US Geological Survey
The New Zealand mudsnail, Potamopyrgus antipodarum, first recorded from North America in Idaho's Snake River watershed in 1987, has added Arizona to its US distribution. Through the 1990's, the mudsnail spread to the waters of Montana, Wyoming, and California, including public lands such as Yellowstone National Park. In the eastern US, P. antipodarum is found in Lake Ontario, where a population was discovered in 1991. While widely distributed through Australia, Asia, and Europe, this species, as it name suggests, is native to freshwater lakes and streams of New Zealand. The snail is capable of rapid population growth, reproducing parthenogenically,and in Yellowstone, localized infestations can reach a density of 28,000 individuals per square foot. In the United Kingdom, P. antipodarum is reported to eat watercress; however, the main concern in the US is that the mudsnail will out compete algae-feeding aquatic insects, the main food source of trout.
The NAPPO web site also has a nice write-up on Pomacea canaliculata in the "Pest Alert" section, with a 14-page data sheet. Go to their website and submit "Mollusks" on the Pest Alert page, if you're curious.

We're anticipating several talks on the subject of molluscan pests at the Charleston meeting this August, including contributions by Jim Smith and by Rob Cowie, the chair of the AMS Committee spearheading this effort. Registration for that meeting will continue until June 30.

*Historical Note:
This paper was ultimately published in 2009:
Cowie, R. H., R. T. Dillon, D. G. Robinson and J. W. Smith (2009) Alien non-marine snails and slugs of priority quarantine importance in the United States: A preliminary risk assessment. American Malacological Bulletin. 27: 113-132. [PDF]

Friday, April 26, 2002

Charleston Symposium

To the FWGNA group,

The Charleston meeting is shaping up very nicely. Here's the current list of participants in our featured symposium, "The Biology and Conservation of Freshwater Gastropods." Their titles are, in many cases, tentative:
  • John Alderman - Evolution of aquatic habitat conservation in North Carolina.
  • Art Bogan and M. Raley - The conservation status of the Magnificent Ramshorn (Planorbella magnifica).
  • Ken Brown - A general review of the conservation status of North American freshwater gastropods.
  • Matthias Glaubrecht - Leopold von Buch's legacy: Treating species as dynamic natural entities, or Why geography matters.
  • Rob Guralnick - Tying together bioinformatics and molecular approaches to discover conservation units.
  • Paul Johnson - TBA.
  • Steve Johnson - Spatial patterns of genetic structure, armature and coloration in Mexipyrgus churinceanus.
  • Eileen Jokinen - TBA.
  • Chuck Lydeard - The Phylogenetic Species Concept and its application in the conservation of freshwater mollusks.
  • Bob McMahon - TBA.
  • Elizabeth Milhalcik & Fred Thompson - The "Elimia" curvicostata species complex.
  • Doug Shelton - The Freshwater Gastropods of Mississippi: Pioneer Survey Efforts in the 21st Century.
  • Tim Stewart - Distribution and status of the freshwater gastropods of Virginia.
  • Jon Todd - Species diversity assessment, sediment impact and point endemism: Problems in conservation assessment for highly speciose rift-lake endemics.
  • Amy Wethington - Conservation issues in the Physa gyrina group.
And as if this weren't enough, that hard-working Amy Wethington has organized a special session entitled "Pulmonate Gastropods In The Laboratory" promising to provide a lot of additional insight into the biology of our favorite group!
  • Susan Bandoni - TBA.
  • Ken Brown - What can radio-isotope methods tell us about grazing in Physa?
  • Thom DeWitt and Brian Langerhans - I. Overgeneralized cues induce maladaptive phenotypic plasticity in a pulmonate snail. Also II. Multivariate selection and emergent impacts of multiple predators in a freshwater snail-fish-crayfish system.
  • Vasiliki Flari - Reproductive endocrinology of terrestrial pulmonates, mainly Deroceras reticulatum, Arion subfuscus, & Helix aspersa.
  • Tom McCarthy - TBA
  • Tom Smith & Rob Dillon - "Social facilitation" accelerates self-fertilization in Physa.
  • Andy Turner - Nonlethal effects of predators on behavior and growth of Physa integra: comparing mesocosm and field experiments.
  • Amy Wethington - Divergence and reproductive isolation in physids among populations of the gyrina group.
Many additional talks and posters dealing with diverse aspects of freshwater snail biology will be contributed. You won't want to miss this meeting! The deadline for early registration (and paper/poster submission) is May 15. Go to the website: http://dillonr.people.cofc.edu/AMS2002.htm

See you here!