With all of the other fossil trips and gig outings, I haven't spent much time in my home range for collecting and this will not do. After a few months of trying, I finally managed to get the stars to align and get out collecting with my buddy Bob. We have access to a bit of a special site (no, I'm sorry, I cannot give access or directions, it's a strict arrangement that is tenuous at best) that has been essentially untouched by development or the activities of other collectors. Sadly, the Arkona area is quickly becoming a problem as it's one of the very last places to find nice fossils in Ontario. The extra pressure on the site is upsetting the locals and noise is building in the area for more restrictions. Not good since interest in fossil collecting has steadily grown while sites continue to disappear. For anyone interested in fossil collecting there, The CCFMS hosts regular, legal field trips that are usually family friendly in both the South and North pits and lead by local experts. Brampton Brick, the company/owner of the two quarries have been incredibly supportive of these trips despite not benefiting in any direct way from the granting of access. I hope that the good relationship between the clubs and BB continues on despite the pressure on the site from new collectors and occasional trespassers. Rock Glen Conservation Area is another spot to visit during the summer. Although the park has limits on the number of fossils you can take, there's a nice little museum hosted by the Lions Club that features many fine fossils from the area. The waterway from the Rock Glen waterfall that feeds into the Ausable river is also nice walk where you can find some really cool stuff on the way in the stream bed or weathering out from the walls of this natural ravine.
In addition to a huge faunal diversity in the rocks themselves, Arkona is an ecologically rich area with healthy populations of many endangered/threatened reptiles and amphibians. The critically endangered Queen snake (Regina septemvittata) is quite common here. This specialized snake tends to eat mostly freshly moulted crayfish though they will resort to fish when prey items are scarce. Also found here are the ring-necked snakes, Green snakes, Milk snake and Dekay's snake. Occasionally, if you can get to the waters edge quietly, you can catch a glimpse of one of the many endangered Map turtles that sun themselves on the rocks along the river. Populations of amphibians are also large and healthy including several frog species, the Eastern newt, Yellow and Blue spotted salamanders and of course, the Redback salamander. It's said that redback salamander biomass exceeds any other animal in their range making them crucial to the food chain. Nearly every log overturned contains several. I have it on good authority that five-lined skinks, Ontario's only lizard, has been spotted here as well.
Insect diversity in this part of Ontario is also quite incredible. Arachnophobes must take note, Arkona belongs to the spider. You will see so much variety in this group of arachnids that I often wonder how there are any prey items left! Every time I go out, I manage to see a new kind of spider (new to me anyways).
Enough with the discovery channel, you are here for fossils.
The three main 'layers' or formations in the area are as follows: A thick, crumbly, claylike and blue-ish grey formation called the Arkona shale. This underlies most of the strata and can be quite thick in places. Exposures are often along the river and are as slippery as ice. When the North pit was active, extraordinary lenses of crinoids, trilobites and starfish could be found. These layers are now under about 20ft of water as quarry activities have ceased and the drainage is blocked by muck. the best days of collecting this spot are far behind us though great work was done by a couple collectors from Michigan in days not-too-long past. Exposures can occasionally cough up tiny goniatites, meraspid Phacops rollers and other shelly creatures which are often pyritized. The odd lens of Arthroacantha sometimes make an appearance as well but the crumbly, wet and unpredictable shale usually has other ideas when you try and dig something out. One more word on this, I've heard that folks who used to dig this layer in the "good old days" would 'cure' their finds before prep for up to two years to avoid them falling apart. There's such a high water content in this shale that you can end up with a box of dusty pieces if you don't dry them slowly. After preparing a bunch of Arthroacantha crinoids from this shale, I can confirm that this is the case.
Next up is the Hungry Hollow, a high-energy reef system deposit that is so tightly packed with fossils, it's incredible. Prepare to get muddy if you tackle this. This layer is usually 3-5 ft thick and is hard to mistake for anything else. Large nodules, corals, brachiopods, bivalves, echinoderm pieces and the occasional trilobite are all present here and visible in the wall. Complete trilobites are very rare to find these days from the layer. Fragile and hard to see in the muck, pieces are much more common. Basidechenella, Crassiproetus, Eldredgeops, Phacops iowensis, Harpidella, Dipluera, Bellacartwrightia and Greenops are some of the trilobites that I, or close friends and/or colleagues have found here, usually in pieces.
Finally there is the Widder formation. The Widder is up to 20ft thick in places where it hasn't been scraped off by glaciers or erosion. This is where I spend most of my time. Although the faunal diversity/occurance from this layer is very low, the best preservation is here. Greenops widderensis trilobites are by far, the dominant fossil in these rocks. They preserve a beautiful chocolate-brown color and often have fully inflated shizochroal eyes. Eldredgeops rana is a distant second though painfully uncommon, especially when compared to the USA side of the Hamilton group.
We had perfect weather yesterday despite high humidity and a mosquito density that bordered on ridiculous. Starting out in the Hungry Hollow layers, I managed to find a little Eldredgeops roller on a concretion. There's a good chance that the tail is either 'punched' or absent but prep will reveal soon enough.
Eldredgeops rana roller in situ.
Moving up into the Widder formation, things were very muddy along the exposure. We've had massive amount of rain this summer which has been great for the farmers and mosquitos, not that great for collecting or for dry socks. After a bit of moving around and checking exposures, both Bob and myself found what we were looking for- Greenops trilobites!
It's hard to get a sense of scale from this photo but my find (on the right) is the largest example of the species I have ever found or seen from the area. Bob's find on the left is the typical size (in the 2.5-2.8cm range). Jugger-nops, as he was dubbed onsite, has a cephalon that's as wide as the typical size. I expect prep to reveal extensive predation on this big boy as it's almost always present on any bugs from this site that exceed 3cm. Both are beautiful specimens and perfect splits, a rare occurrence in this wet, sloppy kind of dig.
Several hours later I found, what I hope to be, a complete Phyllocarid. Phyllocarids are a shrimp-like creature with a long tail ending in three spines. Even pieces of these elusive beasts are uncommon, particularly the telson (tail).
Just about as buried as it can be, there's not much to see feature-wise on this piece. Prep will be the great equalizer as usual.
Phyllocarids also have mandibles, these are usually detached from the body and look rather like an assemblage of human molars. I happened to spot one weathering out in a quiet corner of the stream and rescued it from impending erosion. Features on this specimen differ slightly from ones I've collected in the past, however -once again, the lab will provide the details. I'll attach a photo of a previous find of mine that I prepared, for comparison.
Phyllocarid mandible
A prepared Phyllocarid mandible. Paleozoic dentures.
Keeping us company during the dig were a few species of millipede. The American Giant millipede (Narceus americanus) is the most common to see since they're so huge, sometimes topping 10cm long! A few of them came by investigate.
A millipede I have not-yet been able to identify also made an appearance. If you recognize it, feel free to leave a comment!
A few more finds and it was time to hike out of the ravine. Tired, wet, muddy and victorious!
Stay tuned on the Stormbed instagram and Facebook pages for pictures and videos of these specimens prepared! Thanks for reading, I'm off to another gig but perhaps- a little prep first...
Mike M - August 23rd, 2023 - Owner Stormbed Paleontological - All content is original
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