Some time ago I reported on a mysterious Bulimulus having been found in and near Jacksonville, Florida (see my posts dd. 17-08-2009 and 05-07-2010 on my old blog at www.ashbreure.nl).
Thanks to the unresting efforts of Bill Frank, the story continues…
Made a little in town snail trip today. The conditions were great after the rain we’ve had the past couple of days.
The first stop was behind the Duval Container Company on Hanover Street. During my last visit the place was like a desert (nothing but dry vegetation) but today it was all grown up with fresh vegetation everywhere. It really didn’t look like the same place. The Bulimulus species were all over the place and there was no shortage of Praticolella mexicana and Bradybaena similaris either. It actually looked like the Bulimulus and Praticolella were expanding their limited range. I was truly surprised to find so many snails considering how few I had seen during my most recent visits.
Early this morning I drove down to Main Street near the railroad tracks just south of the Trout River Bridge (AKA Marble Masters, 7621 North Main Street) to check on the Bulimulus population there discovered by my brother and sister in-law on 11/5/2011. I hadn’t visited the location since late December of 2011. At that time I found a good number of juvenile specimens, not many adults, but plenty of empty shells.
Today the species was everywhere (both adults and juveniles) but especially on the sides of buildings in the area along Main Street. I messed around near the railroad tracks for a while and discovered that the species was also on a building across the tracks a considerable distance from the ?main population? near Marble Masters. The species must be quite widespread in that area. I had checked the other side of the tracks back in December of last year and didn’t find any specimens there. All the rain we have been having has obviously been good for the snails.
This morning I headed out to the Bulimulus species site on US-301 just south of Callahan in Nassau County. I hadn’t been there in a long while and during my last trip I reported that the county had graded the roadside swale where the species is found and I was unable to find any living specimens although empty shells were still present. Enroute I stopped at the creek at the Duval/Nassau County line on Lem Turner Road and confirmed my earlier observations that there just aren’t any snails there – not even Polygyra.
As I was driving south on US-301 toward the Bulimulus site I noted with dismay that there is some serious road construction going on. Both sides of 301 have been cleared and graded probably in preparation to making the road four lanes. Fortunately the clearing stopped a scant 25 feet north of the Bulimulus site/habitat. I was worried that I had driven all that way for nothing. However, I think that there is little doubt that all of the habitat (and the snails) will soon be destroyed so I was liberal in my collecting.
To say that there are a lot of Bulimulus would be the understatement of the year as they are just everywhere on the west side of the road for about 100 meters — both adults and tiny juveniles. However, like all my previous trips there the snails are found only under one type of vegetation/weed. Only God knows why but it sure makes them easy to find. The Bulimulus are the only species of snail that I found there – not even a Polygyra. The east side of the road doesn’t have that type of vegetation/weed and there are no Bulimulus there but a modest number of Polygyra.
I went down town today to get a better handle on the exotic Bulimulus species on Main Street near the marble place. There are a whole lot more of them and they are more widely dispersed than I had imagined. Their habitat runs for at least four blocks and includes both the east and west sides of the railroad line. They are obviously doing well in light of the very large number of juveniles. As I had noticed the other day during my Bulimulus trip to Nassau County south of Callahan, the Bulimulus have a special attraction to one particular weed. I found the same weed and attraction in regards to the Main Street population. You would find a patch of this weed out in the middle of a mowed field/lawn and if you looked under it you found live Bulimulus. I tested it with at least 20 patches of the weed and I was 100 percent successful.
Because of the snail/weed attraction I drove across the Trout River Bridge to see what I could find along the railroad tracks up there. Yes, the same weed was found up there too and yes there were Bulimulus underneath it. The finding of the Bulimulus along the railroad tracks on the other side of the river leaves no doubt in my mind that the method of dispersal of these snails is by rail. The two other locations where this snail has been found are also located next to a railroad line. The snails sure didn’t swim or crawl across the Trout River!
A lot more work needs to be done in regards to surveying these guys. I think that there are probably many populations out there just waiting to be discovered. I wouldn’t be a bit surprised if these guys aren’t the next Bradybaena similaris although the Bulimulus appear to prefer a drier habitat then the Bradybaena.
Here is a map showing the Bulimulus sites on Main Street (US-17). I couldn’t find any up by the brewery on Busch Drive. It was so hot out there today that I was soaking wet before I even made it up north of Trout River.
I returned to the Main Street corridor this afternoon to check the CSX Transportation railroad line further north than my trip yesterday to see if the Bulimulus (Praticolella) might be present. A lot of the area doesn’t look good the further north you get. It’s such poor habitat that there aren’t even any Polygyra present – but Succinea are well represented in the wet areas. I did find one more large Bulimulus population just south of Eastport Road today although there too looked like poor habitat for snails. Today’s find extends the Bulimulus another 1.5 miles north with it being 3.5 miles north of the Trout River Site. Cumlulatively counting south of the river on the railroad line (Marble Masters), this brings the total distance where the snails have been found to 4.5 miles – although of course it isn’t continuous but a population here and there along the tracks.
The Eastport Site wasn’t very good habitat for the Bulimulus. They were so desperate for shelter that they were beneath the washed out bank in the ditch hiding in the dirt. When good shelter was present (vegetation) there were a shit-load of live specimens beneath it. The specimens from this site are much lighter in coloration than those from all the other known sites. It was a miracle I found them. I had initially found a single tiny live juvenile a little further north and it took me about a half hour before I hit the mother lode.
Today when I was collecting the Bulimulus sp. at Eastport Road from the dirt bank I noticed that one of them was partially buried in the dirt in a position that might indicate that it was despositing eggs (such as http://www.jaxshells.org/dest2.htm andhttp://www.jaxshells.org/2981j.htm).
Today I drove out North Main Street all the way to Pecan Park Road and snailed my way back towards town. Most of the habitat didn’t look nearly as good in person as it did on the computer using Google Maps. Between that and the fact that overall there really aren’t many snails out there along Main Street, I didn’t find much of anything. Finally at Duval Road/Airport Road I found a single live Praticolella mexicana in the roadside swale. I tore that place apart and finally found a few more empty Praticolella shells and one live subulinid but couldn’t find any Bulimulus or any additional live Praticolella. Overall I made about six stations. On the way home I stopped at Eastport Road again and surveyed it a little more. There are a lot more Bulimulus there than I found yesterday — of which at least half of them are almost pure white in coloration.
Since it is obvious that this Bulimulus likes traveling ‘on the edge’ (see below), there might be further localities to be found once the surveying continues.
Many thanks Bill for your excellent field work!