Wednesday, September 14, 2011

Day 40: Crop circles and killi-clemency

Upon arrival I found the marsh plagued by unexplained phenomena. What you see below was one of several circular formations, each stretching about thirty feet in diameter. There could only be one rational explanation.


Then I recalled reading about these circles. During late summer, large patches of salt hay (spartina patens) lay down in matted, swirling patterns aptly named cowlicks. The dying grass, usually out of the tides' reach, stays in place and does not effect the succeeding generation's growth. In fact, it stabilizes the substrate.


I started the day trying to operate the seine by myself. This ranks high among those two-person tasks whose doubtless failure as a solo endeavor only goads one into attempting success. Fortunately, Moshe was available. When operated correctly seine nets are very effective at skimming the nano debris, especially particulate plastic, from the marsh surface.


The problem is they're also very effective at skimming the organisms that swim in the marsh. After unraveling the net we found the debris jerking with dozens of frantic killifish. Some might say you can't make an omelet without breaking a few eggs. And killifish are legion, yes. But they're also the most voracious predators of my sworn enemy, the salt marsh mosquito. How many blood-sucking insects would live for each killifish that perished? I didn't want to find out, and so began the exacting work of picking the killis, one by one, from the net. 


And liberating them.


Those that could not be saved, I reassured myself, would make good treats for whatever lurks around the debris piles.

We attempted to scare fish away during subsequent skims by walking in front of the net. This tactic significantly reduced bycatch, and would work much better with a third person, a dedicated fish herder, leading the net draggers. In the end, the seine was worth the sacrifice.


and


I finished the day in the shop preparing for Saturday's cleanup event. Hope to see you there.

References:

The Effect of a Seasonal Change in Canopy Structure on the Photosynthetic Efficiency of a Salt Marsh.
S. N. Turitzin and B. G. Drake. Oecologia. Vol. 48, No. 1 (1981), pp. 79-84

The Behavior of Fundulus heteroclitus on the Salt Marshes of New Jersey. F. E. Chidester. The American Naturalist.
Vol. 54, No. 635 (Nov. - Dec., 1920), pp. 551-557

High of 82, max humidity 90%, average wind SSW @ 10 MPH, 5.7 high tide @ 9:36 AM. Moon 98% visible.
Water level recorded at 10 inch mark.
Birds seen in marsh: belted kingfisher, green heron, osprey, great egret
Birds seen in bay: great egret

3 comments:

  1. LOL on your first explanation. Thanks for the laugh. Growing up next door in Rockaway Point we called what you did "dragnetting", to scoop up the fish for bait,the opposite of what you did yesterday.
    I'll see you on Saturday, I plan to kayak over weather permitting. Cindy will be there too. Keep up the great work,
    Andrea

    Thanks

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  2. Saw this blog on the Awl, totally love it. I'm going to go back to Day 1 and read it all. I grew up in Breezy but never went over to that area, which we called "The Cove". In the 70's, the older kids tried to grow marijuana back there. It was (and still is) no-man's land.

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  3. Jakubowski, that is amazing. Any chance you have photos of The Cove from back then? What was it like? Sorry I'm responding so late

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