To Only Know Invasives in My General Vicinity ...

Editor’s Note – This essay was subsequently published as: Dillon, R.T., Jr. (2019d) To Only Know Invasives in My General Vicinity.  Pp 73 - 79 in The Freshwater Gastropods of North America Volume 4, Essays on Ecology and Biogeography.  FWGNA Press, Charleston.

A couple years ago I received a cordial email from a young lady working with a natural resources agency in a big Midwestern state.  She was looking for help developing a key to identify invasive freshwater gastropods in her general vicinity – not the native species, just the important ones.  Here’s what I suggested:

1a) Operculum present . . . (2)

1b) Operculum absent . . . never mind.

2a) Really big! . . Potentially devastating economic impact.

2b) Little . . . (3)

3a) Only a few of ‘em . . . screw it.

3b) Bazillions of ‘em! . . . Potentially devastating economic impact.

So last month we reviewed the USGS Nonindigenous Aquatic Species database [1], an open and earnest federal effort to monitor the distribution and spread of invasive species in the nation’s lakes and rivers, including (at this writing) 42 freshwater gastropods.  This month we’ll broaden our field of view, but sharpen our focus, looking toward state-level invasive species monitoring programs.

State interest in invasive species is typically directed rather narrowly toward perceived threats to agriculture or commerce or human health.  At the very least, the doggone thing from China or wherever it says it came from has got to make itself a nuisance.  So for example, my home state of South Carolina doesn’t really care about the huge populations of invasive viviparids in our reservoirs, unless (I suppose) there’s a significant die-off, and somebody complains about the stink [2].  Which sounds like a problem solving itself.  The South Carolina DNR does, on the other hand, care about our invasive populations of Pomacea, primarily because of its potential to host the rat lungworm [3].  More about that in a future post.

The states of California, Oregon and Washington all care about the current range and future spread of Potamopyrgus antipodarium, the “New Zealand Mud Snail” because, to quote the Oregon Department of Fish & Wildlife’s modest web page [4], “there is concern [about] devastating effects to recreational fishing.”  So for more information, Oregon directs its citizens to the New Zealand Mud Snail page at the USDA National Invasive Species Information Center, from whence they might surf over to the USGS-NAS database and report their observation. 

California has developed a larger page on Potamopyrgus, featuring the snail on one nice, colorful poster and one blunt, scary poster (left), both available for download [5].  In addition to mentioning the USGS-NAS database, citizens of California who have observed Potamopyrgus are asked to call or email their Department of Fish & Wildlife directly.

Like California, the State of Washington also has a nice web page devoted to Potamopyrgus, with a downloadable fact sheet, although no keen posters [6].  There is, however, a “Report online” link from the Washington Potamopyrgus page where a citizen might open a (vanilla) online reporting form to send a potential sighting to the Washington DNR.  Or one might elect to download a “WA Invasives” app for one’s smartphone.  Impressive.

The point I’m making here, however, is that none of these three states apparently gives a rip about the populations of European Lymnaea (Radix ) auricularia which have spread all over the American West in the last 100 years, but apparently have not risen to the level of a threat, or a pest, or even a “nuisance.”  You’re just a fat little brown snail.  No smartphone app for you.

There are exceptions to this general rule.  Back in 2011 we featured a “Citizen’s Watch” initiative in the state of Wisconsin [7], broadly charged with monitoring invasive species of all sorts, as well as general aspects of the physical environment, water quality, and so forth, for specific lakes.  The Maine Volunteer Lake Monitoring Program [8] also features an invasive species component which, although focused on aquatic weeds, includes a mechanism to report “suspicious” aquatic organisms of all phyla.  Click the header below for the entire form:

The high end of invasive species monitoring programs seems to be occupied by a set of nine states (and one Canadian Province) who have adopted a NatureServe system called “ImapInvasives.”  This is an online system that rivals (and in many respects, surpasses) the USGS-NAS database in its scope and versatility.  Open the link below in a new window and check it out, if you’re not already familiar with the program.

iMapInvasives [html]

If you click the “Login/Maps” button at the top of the iMapInvasives home page you will find a list of the ten states and provinces currently subscribing, from whence you might be tempted to follow links to try the system out.  ImapInvasives is designed as a monitoring system for exotic biota of all sorts – weeds, bugs, slugs, stoats, goats, giraffes, Giselles, and especially rabbits.  Only four states list freshwater gastropods on their public maps at present: Maine (Bellamya), Pennsylvania (Bellamya, Potamopyrgus), Oregon (Bellamya, Potamopyrgus [9], Melanoides), and Arizona (Bellamya, Melanoides, L. auricularia).

The “public maps” viewable from the several states listed above are disappointingly low in their resolution – returning just county or watershed (8-digit HUC) of record, not the precise locality.  They also show only a subset of the species actually tracked, in some cases.  To see a detailed map, or access locality data, or contribute fresh data to these systems, one must be a registered user.

Over the last couple years I have developed a cordial relationship with Ms. Amy Jewitt, the invasive species information assistant working for the Pennsylvania Natural Heritage Program.  She offered to register me for the Pennsylvania site, and I can report that it is as easy to use and informative on the inside as the USGS-NAS system is on the outside. 

Bellamya chinensis on iMapInvasives

Pennsylvania actually tracks the entire rogue’s gallery of invasive freshwater gastropods in its iMapInvasives system as implemented for registered users, including Bithynia and Viviparus as well as Bellamya and Potamopyrgus.  The Bellamya are sorted correctly (I have reason to think) into 33 records of chinensis and 18 records of japonica, with just one single record of “species uncertain.”  The reason I have reason to think the Pennsylvania identifications are correct is that most of their records are ones I forwarded to Ms. Jewitt from the FWGNA database back in 2013.  And she continues to send me jpegs for identification, as new sightings are reported.

So how well-coordinated are the state and federal efforts?  One of my prompts to launch the present series on invasive species came in late September when I happened to receive emails from both Ms. Jewitt and Mr. Matt Cannister, a contractor working with the USGS office in Gainesville, both with attached Bellamya jpegs.  Mr. Cannister’s response to my question was quite positive: “there is usually a high level of information sharing between state and federal biologists and ourselves here at NAS.”  Ms Jewitt was more guarded, albeit hopeful:

“As of right now, we do not have any of the USGS data in PA iMap and we have not sent any of our data to them, though we hope to change this in the very near future.  There is one big task that needs to happen on our end first before we can begin data sharing with them; however, once that happens, the PA iMap database will certainly have much more useful information to provide.”

I should conclude this month’s essay by re-assuring everybody that I thumbs-up-like online governmental programs to monitor invasive species.  They are a mixed blessing for the FWGNA project, which is, after all, an effort to survey of an entire fauna, and subject to the phenomenon I identified last month as invasion-biased oversampling.  But nothing I have written in my last couple posts is intended to reflect negatively on the hardworking public servants at any level, state or federal, who are doing their best to deal with the rising tide of exotic species inundating our shores.

Budgets are small and personnel are few, and I certainly understand why natural resource agencies must pick (at most!) a couple invasive freshwater gastropods that seem the most intimidating, and (on the flip side) a couple nominally “endangered” freshwater gastropods that seem the most pathetic, and let the other 95% of our North American freshwater gastropod fauna fend for itself.  They’re just little brown snails.

Notes

[1] To Only Know Invasives [16Oct15]

[2] Just Before the Bust [5Aug14]

[3] Pomacea Spreads to South Carolina [15May08]

     Two Dispatches from the Pomacea Front [14Aug08]

     Pomacea News [25July13]

[4] Oregon Department of Fish & Wildlife [New ZealandMud Snails]

[5] California Dept of Fish & Wildlife [New Zealand Mud Snails]

[6] Washington Invasive Species Council [New Zealand MudSnails]

[7] Dispatches from the Viviparid Front [12Sept11]

[8] Maine Volunteer Lake Monitoring Program [html]

[9] Alert readers will notice that I just reviewed the Oregon Potamopyrgus page about six paragraphs earlier in this essay, and said nothing about iMapInvasives.  Yep, strange but true.  I cannot find a link from any agency of the State of Oregon to iMapInvasives.  Maybe this is just an oversight?  But it is consistent (I am afraid) with the general inhospitality of the iMapInvasives system.