Wednesday, July 24, 2013

Testing the Waters With Evelyn


If not for my friend Evelyn Greene's invitation, I would never have been able to paddle the beautiful Adirondack Lake (which shall remain nameless) we visited together this past Monday.  Although surrounded by state land, the lake can only be accessed by auto through a private homeowner's association, which had applied to the Adirondack Lake Assessment Program (ALAP) to have the lake's water tested for quality.  As a member of the environmental advocacy group Protect the Adirondacks (a major sponsor of ALAP), Evelyn had volunteered to collect water samples to later be analyzed for acidity, alkalinity, mineral content, and a number of other factors.  She invited me along to help balance her canoe as she conducted several tests.  And I'm glad she did.  I always have fun with Evelyn.

Here Evelyn demonstrates the use of a Secchi disk, a weighted black-and-white disk that is used to determine water clarity.  After paddling out into deep water, Evelyn lowered the disk on a measured cord until she could no longer see it, then made note of the depth, determined by measuring the length of cord used.




Here she is using a long hollow tube to collect water from the depths of the lake, water that she then poured into collection bottles that would be sent to a laboratory for further analysis.




Her testing tasks accomplished and the collection bottles stored in a cooler, Evelyn then led me across the lake to where it entered an outlet flowing into a small shallow pond.  Since the outlet stream was too shallow for paddling, we pulled our canoes a short distance through the woods to launch again on the pond.





The pond was very shallow, and it was almost completely filled with the underwater structures of Purple Bladderwort  (Utricularia purpurea),  the brown frothy stuff in this photo.  (In all the pond, we found but a single bloom of the bladderwort  protruding above the water.)  Emergent plants included Water Lobelia, Water Bulrush, and most unusual, the flowering stalks of Slender Milfoil (Myriophyllum tenellum), one of our native milfoils that is only rarely found in bloom, although its tiny pinkish flowers were very much in evidence on this little pond. 




Plants that floated on the surface of the pond included Fragrant Water Lilies, Yellow Pond Lilies, and the super-abundant Water Shield (Brasenia schreberi), its spiky pink flowers protruding above its oval pads.


 Slithering around beneath all this vegetation were myriad leeches, big greenish-brown ones at least four inches long that would quickly approach my hand whenever I reached into the water to examine a plant.  Yikes!  I soon discovered I could attract them just by dangling my fingers in the water.  I wonder how they detect the availability of fresh blood to suck:  by motion, odor, or temperature?  I didn't let them suck any of mine.




The vegetation along the shoreline of this pond consisted mostly of Leatherleaf shrubs gone to seed,  but here and there we found a few flowers in bloom, including this patch of bright-yellow Horned Bladderwort (Utricularia cornuta) sharing its sphagnumy spot with Marsh St. Johnswort (Hypericum virginicum) and White Beak Sedge (Schoenoplectus subterminalis).  I think there were a few cranberries in there, too.



Here's a closer view of that White Beak Sedge, a familiar sight in northern marshes and bogs.





Evelyn had studied the maps and hoped to find a navigable outlet to this pond, but when we found it, we discovered its access was impeded by a beaver dam, and the water beyond was much too shallow for paddling.   There were huge heaps of beaver sticks on either end of this shallow dam, indicating that there might have been a much higher dam at this site in the past.




We decided this was a nice shady spot to perch on rocks and eat our lunches, so we got out of our boats and explored the shore.  Masses of Creeping Snowberry (Gaultheria hispidula) carpeted the area, but in all those leaves I could find but a single tiny white waxy berry.




The bright red fruits of Bunchberry (Cornus canadensis) presented a lovely complement to the snowy blooms of Dalibarda (Dalibarda repens).  There were bushes laden with blueberries, too, which provided us with a sweet snack.





What a pretty still life, the vivid yellow of the mushroom set off by the little green hearts of the Wood Sorrel leaf.




Oh dear, yet ANOTHER creature snared by a spider's web!  That seems to be my calling of late, releasing trapped damselflies and dragonflies from sticky webs.   I didn't know if I could completely remove all the filaments from this Ebony Jewelwing, but I freed enough of it anyway, that it promptly flew away with its distinctive fluttery flight.




Leeches are really hard to love.  But I try.  All God's Creatures, and all that.  When I saw one resting on a rock just under the water from where I was eating my corned beef sandwich, I even tossed it a morsel of the salty pink meat, which landed an inch away from its front end.  Oh my, you should have seen it lunge for it and take it into its suckers with seeming great eagerness.  And then the most awful thing happened.




With the glob of meat stuck in its "mouth," the leech began to writhe and twist, writhe and twist, as if in agony, but it never dislodged the piece of meat.  Could the salt in the corned beef be causing it terrible indigestion?  Why couldn't it spit it out?




Well, it seems it was worse than indigestion.  The creature eventually stopped writhing and went completely limp.  I picked it up on a stick and it just drooped without any tension.  I do believe it had died.  How awful!  I confess I do hate the thought of a leech attached to me, but I never meant to harm it.  Could the salt in the meat have killed it?  But our blood is rather salty, too.  Who would have thought?  Gosh, I'm sorry, leech.




Paddling back across the lake, I saw many Water Shield pads just covered with the spiky skins of Water Striders.  At least I knew that these creatures had not died, but rather had shed their skins as they transitioned to another instar.  (Thanks, BugGuide.net, for this information.) I wonder if the insects climb aboard these pads to perform the molt, or do the shed skins just happen to collect on the slimy surface of the pads?  Another mystery to ponder.


7 comments:

catharus said...

Very interesting story about the leach...
Yes I recall using those same instruments and collection vessels for a student research project (as well as collecting sediment for surveying invertebrates) many moons ago...

The Furry Gnome said...

What an interesting exploration! I particularly like the photo of the bunchberry; good composition.

Virginia said...

Your first lines caught my attention with the water testing since we are so involved with that in Sierra Club, but, now, I am totally taken with the leach story and all those water striders on the lily pad. You see so much with your intimate view. Beautiful photos and fascinating narrative.

Woodswalker said...

Thanks for your kind comments, catharus, Furry, and Virginia. I really love knowing you come along with me on my adventures.

Ron Gamble said...

So many great stories and photos on your blog lately! Besides botany, your water quality work sounded so interesting...

Leeches: We swam with the big green ones in Minnesota, they didn't attach (don't know if the same is true for yours), but the little black ones are a different story. Attachment spots would "spot-bleed" for 3 hours after removal... (Just use band-aids).

Spiders have to eat too :-) .

Speaking of eating, your prior post of food looked fantastic! I SO wanted to consume... :-)

Woodswalker said...

Thanks, Ron Gamble, for your kind comment. I remember very well those small black leeches (and how we would bleed) from my childhood growing up on a Michigan Lake. I didn't keep my hand in the water long enough to see if the big green ones would try to attach. Maybe next time. Or maybe NOT! You're right, Ron, that spiders have to eat, and now I feel guilty for releasing the damselfly. Except that the damselfly's struggles had pretty much destroyed the web already.

Ellen Rathbone said...

Bummer about the leech! Reminds me of putting ants in anchovy sauce way back many many years ago...they didn't like it, either.

On the other hand, REALLY cool shot of all those water strider cases!!! I've never seen that. Sure answers the question I had this summer about whether they molt or not!