Shoreline Outing Summary: Williams Beach, High Tide, November 28th, 2018

We had a good turnout on a mild and bright Wednesday morning at Williams Beach for the second highest tide of the year. While confined to a narrow strip of shore between the gentle waves and the slippery, imbricate logs, we managed to see quite a lot. The following are some notes and observations related to the outing.

(1) Shoreline Erosion and Sea Level Change
Around these very high tides, particularly in wet and stormy weather, is when you can see the ocean eating away at the shore. With rising seas, shoreline erosion with increase. In our region, changes in sea level have both global and regional underpinning. On the global level, the melting of glaciers and ice sheets is taking a volume of water previously sequestered on land and returning it to the oceans. Increased ocean temperatures also also lead to some thermal expansion of the volume of the oceans. The IPCC 2017 assessment and modeling of sea level rise attributes about 20 cm of sea level rise over the last 100 years to this flux from ice to ocean. Furthermore, it predicts anywhere from another 20 to 100 cm rise by 2100.

Locally, sea level change is complicated by two other factors– land level changes associated with tectonic activity (earthquakes and crustal flexure driven by the accumulation of strain near the subduction zone) and the slow rebound of the Earth’s crust in our area after it was buried under 1-2km of ice at the peak of the ice age. Locally, a recent paper by Fedje et al. provided evidence for sea levels being almost 200m higher. The map below is from the linked paper and shows the location of paleoshorelines in the Quadra Island area circa 14,000 years ago. We saw a much more recently exhumed shoreline just above the present beach.

(2) The Midden
We saw the dense concentration of clam shells in the bank from which Betty pulled a stone pestle some years ago. There was some discussion about how to distinguish human deposits of shell material from the “lags” of shells that typically accumulate by wave, tidal and current sorting. Some criteria: the biological composition of the shell material, vertical and lateral extent of the deposit and the prevalence of interstitial cobbles and sand. The troughs in which shells naturally accumulate tend to follow depositional bedforms  that are either laminated or swooping and typically on the scale of ~1m or less in lateral extent and typically around  cm-scale vertically.

(3) Stuff thrown up by the ocean.
We found a potpourri of seaweeds. Below from left to right are some of the common ones- Saccharina sp. (Sugar Kelp), Nerocystis sp. (Bull kelp), Sargassum sp. (Japanese Gum Weed), Ulva sp. (Sea Lettuce), Constantia sp. (Cup & Saucer), Chondracanthus sp. (Turkish Towel)  and Gracilaria sp. (Red Spaghetti).

Gary discussed how their colours and depths are controlled to some extend by the types of chlorophyll present in the species. Some of the more drmatic coloration at this time of year has more to do with the breakdown and loss of chlorophyll and pigments.

We saw some interesting animals, most notably a pacific sand lance (presumably hanging out in the abundant sands just below the high-tide line at Williams Beach) and a large sponge kicked up by the surf from the subtidal flats.

The identification of sponges is challenging as keys focus on spicule characters. The spicules are structural elements, typically rods of mineral material that are encased in organic compounds. I prepped out some spicules using standard household bleach and found these lovely ~100 micron spicules (“Tylostyles”) of SiO2. Turns out this thing is called “Dead Man’s Fingers”, Homaxinella amphispicula. It is a demosponge, which is to say a mixture of organic structural elements and mineralized ones. It is a subtidal species, so likely kicked up during a very strong storm around the wave base.

There are upcoming late night low tides. The plan is to head to miracle beach at night with headlamps to see what is stirring. I’ll send around a date later this week.
Thanks everyone for coming out and contributing.
See you soon,
Randal

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Botany Outing Report: Fungi and Soup, Nov 19th, 2018

Botany Group Report  : November  19th Outing Tsolum River Road

The range of fungi for later November was still large.  Of note we identified many large Russula brevipes – short- footed russula- that heaves up moss, turf, branches etc. ( see photo + slug). We also found one Russula xerampelina  – shrimp russula  (specimens of which were in the soup).  We saw lots of Inocybe species, and the Hypholoma fasciculare – sulfur tuft – in its various stages from young button to degraded soggy  brown “mush”.  Curiosities included the Pseudohydnum gelatinosum  – cat’s tongue (see photo)  and Nidula candida -bird’s nest fungus.  I failed to find a specimen of Xylaria hypoxylon – carbon antlers, so see attached photo taken on the Tuesday.  Also, another intriguing late fall fungus that eluded me on Monday (Jocie not being with us!)  was the Auriscalpium vulgare   “earpick fungus” .   It falls into the tooth/spine morphological group and is another example of a fungus with very specific environment – Douglas fir cones – see attached photos.


Cat’s Tongue                                                                   Carbon Antlers

  

Lactarius w orange latex                                        Russula brevipes

The Lactarius that we found near the end of the walk turns out to be Lactarius aestivus,   not in Truedell and Amirati (where it would still be subsumed under Lactarius deliciosus var. deliciosus.)  It was larger than the Lactarius subflammeus, of which we saw hundreds, and much more robust, with orange (not white) latex (see photo).

Here is the general entry on L. aestivus  from Matchmaker ( no photo however) :

Features of Lactarius aestivus include 1) viscid, orange, zonate cap, 2) subdecurrent to decurrent, crowded, orange gills, 3) orange and whitish stem that may be scrobiculate, 4) scanty bright orange milk, 5) grayish green staining of some parts (but not extensive and conspicuous), 6) fruiting under true fir and hemlock.   (scrobiculate means pitted with indentations , in other words it is not a smooth straight -sided stalk).  All these macro characteristics fit.   See photo  attached.

It is well illustrated and described in Siegel and Schwarz “Mushrooms of the Redwood Coast”  and they note that in their opinion it is the best tasting of the “deliciosus” group.  It is less grainy and firmer, which is my experience.  I did pick and cook up more caps (the stipe is too tough).

Next Gathering : Christmas Potluck lunch  Monday Dec. 10th, 12.30 pm

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Guest Speaker: Terry Thormin, Sun. Nov. 18, 2018

CVN invites the public to learn about Nature Photography

Comox Valley Nature is pleased to host a public lecture. Join Terry Thormin for an illustrated talk entitled: “Nature Photography in the Comox Valley” The lecture is on Sunday Nov. 18, 2018 and will start after introductions at 7pm in the Rotary Room of the Filberg Seniors Centre 411 Anderton Ave, Courtenay.

The Comox Valley has a diversity of ecosystems ranging from marine intertidal estuaries, rivers, marshes, forest and subalpine mountain habitats. These habitats are home to an abundance of organisms. Nature photography is critical for documenting habitat and species diversity in the area. These images can also serve as a record of biodiversity and can generate an increased interest in nature by the general public.

Terry Thormin is a very accomplished photographer with an impressive collection of images that include landscapes, plants, fungi and a variety of animals such as insects, spiders, fish, reptiles, birds and mammals. Terry has worked for a private ecological consulting company based in Edmonton, Alberta, doing mostly bird work, and much of it in the Canadian Arctic. He also freelanced for a couple of years before joining the staff of the then Provincial Museum of Alberta (now the Royal Alberta Museum) as a foreground artist working on dioramas. He then switched to the newly formed Invertebrate Zoology Program where he stayed until he retired in 2006. He now lives in Comox on Vancouver Island, B.C.

This is an excellent opportunity for the public to learn more about nature in the Comox Valley and nature photography.

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Botany Outing Report: Paradise Meadows, Oct 15th, 2018

Report on October 15th walk 

For those who missed the report at our last general CVN meeting, for the October 15th gathering we had a glorious day to meander around the Paradise Meadows loops, collecting the SWI plant signs to store for the winter. In fact it was Frank N. who collected most of them while the rest of us enjoyed the fall colours of the vaccinia  etc. and investigated a number of interesting fungi.  There were still lots of berries on the bog and dwarf blueberries, and so it was not surprising to learn that one of our group who went up earlier saw wet imprints of bear paws on the boardwalk.  By the time we walked around the Boardwalk was dry. Among the fungi, Ruth identified a new bracket polypore for the Paradise Meadows list, namely Porodaedalea pini, on the trunk of a still living abies species. It is one of the species that causes white-rot in heartwood. We found a number of different species of Cortinarius – the one in the photo taken by Sharon is  Cortinarius phoenicius var. occidentalis, commonly called western red dye since the rich burgundy of both cap and gills is much prized by those who use fungi for dyeing.

Then we shared lunch with the Canada jays on the picnic table outside the Wilderness Centre.

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