13 September 2010
Canada: Nova Scotia: Annapolis County: 1821 Highway 201, Round Hill, 8.5 km ENE Annapolis Royal. 21A/14, 44.77300N 65.40511W TIME: 1821-1917. AIR TEMP: 16C, cloudy, Beaufort light air. HABITAT: brushy/treed homesite with rough lawn above rocky brook. OBSERVER: Frederick W. Schueler, Aleta Karstad Schueler, Bev Wigney. 2010/286/g, visit. natural history. Rock-flipping Day survey of Bev's place.
Looking around the yard and surrounding brushy areas, I confirm my previous impression that this site has a serious deficiency of real rocks: the primordial stoniness of Nova Scotia seems to have been gathered up and incorporated into the foundations of the buildings by the earlier occupants of the site. I'll, accordingly, mostly be turning bits of artifactual cover rather than real stones.
Under a brick by the front steps, there's only one Sowbug, and nothing under a stack of dinner plates left embedded in the grass by the previous owner. Earlier in the day, I'd found one dying cf Succinea putris "Amber Snail" here, a species which Bev had found to be so abundant earlier in the summer that she assured us that we'd find them "everywhere," but which have evidently matured, laid their eggs and died.
There's many adult Sowbugs, with one juvenile and several adult Deroceras reticulatum "Grey Field Slugs" under bricks and old cabinet doors behind the house, and a collapsed cardboard box under a Lilac sheltered 3 Cochlicopa "Pillar" snails, 7 flat wide-coil Oxychilus snails, a few small Deroceras reticulatum, 3 baby Arion slugs (Aleta says "maybeArion sylvaticus" - we'll have to raise them to maturity to be sure), and a multitude of Sowbugs, including little fast-running ones, and a Millipede that escaped capture.
Seeing a metre-high pile of real, if small, rocks (and small chunks of concrete) among Rubus idaea (Red Raspberry) and Solidago (Goldenrod) beside a ruined shed, I push through the bushes and young Ash trees towards it; Bev reminds me to proceed carefully, because the slope below here is rich in broken glass and other old rubbish. There's a couple of minute snails and a few more little Arion under some rotten boards, but when I burrow into the pile of stones there's nothing but a few Sowbugs, one Millipede, and a couple of small Earthworms. So far, the only creature I've recognized that might be a native species is the Cochlicopa snails, but it's suspected that the "synanthropic" linages of these, which live human-disturbed habitats, in fact may be introduced from Europe, rather than natives.
That pretty well exhausts the available cover. There's plenty of bits of cover under the bushes and thickets, where undercover species may live, but they're not accessible to me. Aleta saw one "Wooly Bear" Pyrrharctia isabella (Isabella Moth) caterpillar out and active, looking for some cover to winter under. In the front yard there's a pile of new "treated" boards embedded in a tangle of Aegopodium podagraria (Goutweed), but these sheltered only a couple of Sowbugs and a juvenile Deroceras reticulatum, while a couple ofDeroceras reticulatum was all that could be found under pottery bowls in the grassy flower garden in the front yard.
Sowbugs, Succinea putris, Deroceras reticulatum, Oxychilus, Arion, and Earthworms are all believed to be introductions from Europe, and their dominance here illustrates how little we can comprehend what we'd have found if we'd been able to flip rocks before European colonization of North America.
Those who are interested learning more about the introduced and native species of snails and slugs can order. . .
Grimm, F. Wayne, Robert G. Forsyth, Frederick W. Schueler, & Aleta Karstad. 2009 . Identifying Land Snails and Slugs in Canada: Introduced Species and Native Genera. Canadian Food Inspection Agency, Ottawa. iv+168 pp. http://www.inspection.gc.ca/
. . . or
Grimm, F. Wayne, Robert G. Forsyth, Frederick W. Schueler, & Aleta Karstad. 2009 . Identification des escargots et des limaces terrestres au Canada: Espèces introduites et genres indigènes. Agence canadienne d'inspection des alimentes. Ottawa. iv+168 pp. (translation of Identifying Land Snails and Slugs in Canada, edited by Isabelle Picard). http://www.inspection.gc.ca/
. . . from the Canadian Food Inspection Agency, at no cost, by calling 1-800-442-2342, and requesting a copy during business hours, eastern time. This is the first work to treat the entire Canadian fauna of terrestrial Gastropods, and we hope that its free availability will lead to an increase of interest in the life history, ecological roles, and systematics of Canadian land snails and slugs.
Nature notes and photos from BC, Canada, mostly in the Lower Fraser Valley, Bella Coola, and Vancouver Island.
Monday, September 13, 2010
Copy of Fred Schueler's report for IRFD
Dave tells me that Fred Schueler's Google doc returns a 404, probably because he sent it as an e-mail attachment. So I've copied it here instead.
I'm having to moderate all comments because Blogger seems to have a problem notifying me. Sorry about that. I will review them several times daily, though, until this issue is fixed.
Also, I have word verification on, because I found out that not only do I get spam without it, but it gets passed on to anyone commenting in that thread. Not cool!
Subscribe to: Post Comments (Atom)
Thanks for this. Very interesting snapshot of introduced versus native rock-dwellers.ReplyDelete