Saturday, July 31, 2010
The Pine Grove covered bridge is immediately downstream from the Chester County water plant and sets the tone for this place where old and new seem to meet and blend. But even part of the old is a facade. The covered bridge was rebuilt atop steel beams. I slid into the water at the downstream end of a large pool just around the first bend downstream from the bridge.
Corixids, which are flying insects with the ability to swim, feed off the bacterial algal ooze that accumulates on the bottom of the slow moving backwater. I have never seen these animals in the wild, only in swimming pools, and their mottled tan wing covers are much more attractive here.
The rocks in the main flow are all covered in sponges infused with sand and sediment so they aren’t so obvious until they are touched. I was transfixed by the concept of freshwater sponges since I studied streams in high school. My teachers told me about a patch of them in a local stream, but I was never able to locate them. When I think of sponges I think of marine systems, and this was part of my amazement. Now, 30 years later, I finally find some freshwater sponges, but they are nothing like the animal I had pictured: upright typical sponge form. Instead, they are encrusting and dirty with silt and sand. Ancient organisms covered by the new problems of sedimentation and increased scouring flows.
A young eel hunted between rocks on the bottom unaware of my presence and a small northern water snake swam over my left shoulder and under my right arm as I tried to snap a picture of the eel.
A Chinese mystery snail lay upside down and was encrusted into the bottom by sponges. These invasive snails have the ability to filter feed, and I wonder if that is what this one was doing. It found a safe place in the stream bed, was protected by encrusting sponge and filter fed for food. New biology, in the form of a recent addition to our aquatic systems, the Chinese mystery snail, and old biology in the form of freshwater sponge meet and become intimately associated here, like the covered bridge and water treatment plant.
Friday, July 23, 2010
Three Mile Island scared the crap out of me when I was 12. It came close to melting down and I remember being very concerned for my aunt, who lived in a nearby town that would have been eliminated had the ultimate disaster happened. I went to see the movie the China Syndrome not long after and that cemented my hate for nuclear power that lasted through young adulthood. I have mellowed a bit with age, and now recognize that the culprits in all energy related calamities are us. We are the ones that create the demand, and demand cheap energy. Not the oil, coal or nuclear power companies. I have learned that when I’m wagging my finger at someone else, three are pointing back at me.
So today I slid into the water upstream of the Three Mile Island nuclear power plant at the canal lock recreation area. The lock haven dam is just down stream from that, and backs up the Susquehanna to supply cooling water to Three Mile Island, and potential energy to the York Haven dam and powerhouse. Just about anywhere I have snorkeled on this river is affected by energy production in some way, and the water from the lower river is used by hydro, nuclear and coal fired plants to give us the energy we need to maintain our lifestyles.
The river here is typical Susquehanna, big expansive shallow water, with numerous rock outcrops. An assortment of invasive shells, an invasive jambalaya of sorts; mystery snails, corbicula, and rusty crayfish carapaces, were piled in a dry eddy.
I slipped into the water and 5 crayfish rocketed in different directions. They are everywhere, and I can’t make any move without causing one to shoot off out of sight. I am fairly certain these are the invasive rusty crayfish, with large claws and rust colored patches on the sides of their carapaces. They are so abundant, they must surely have an affect on the ecology here, especially on the benthos, but benthic fish, like tessellated darters, don’t seem to be affected as they appear to be almost as abundant. Virginia river snails are also common and they leave grazed patches and trails where they have eaten the slick biofilm on the smoothed slabs of bedrock, but they may be affected. Maybe Virginia river snails are less abundant here than other places like the mouth of the Octoraro because of the crayfish. There are lots of dead shells of another invasive, Chinese mystery snail, but where are the live animals? Are they hunkered down in the substrate?
This is used water, used by power companies and industry, farmers, city dwellers and suburbanites. But then any river in North America is heavily used. Invasives, like many of these crayfish, Chinese mystery snails, and now for the Susquehanna, zebra mussels, are one of the leading causes of globally declining freshwater biodiversity. And I wonder what the biggest danger is, or will all these threats work in synergy to finally destroy whatever is left of our freshwater ecosystems? I’m sure that the system I observed in a few feet of water today little resembles the ecosystem that was here pre European settlement. So while it may not be pristine, it is still amazing.
Sunday, July 11, 2010
I used to avoid the larger eddies, those areas of sluggish water behind rocks and shoreline aberrations. The slower moving water created by the upstream obstruction allows the finest silt particles to settle to the bottom and expanses of barren mud-covered flats extend downstream. I always thought of muddy eddies as lifeless, and I usually created chocolate milk water conditions by accidentally stirring the fine bottom before I could really see who was living in these areas.
I skimmed over one of these eddies on my way to what I thought was the more interesting habitat of a cobbly riffle when I came upon a line in the mud that led 5 feet or so to a Virginia river snail slowly but surely making its way upstream. In the moment I paused to admire the snail, other life became apparent. Tiny squiggles of new fish schooled in a small hazy cloud. Black smudges of other kinds of fry swam towards me to investigate. Comma mark toad poles squiggled along the bottom. The importance of this perceived lifeless barren became apparent: this is a nursery for the stream, and suddenly, this barren wasn’t so barren.
Sedimentation results in the loss of habitat and is one of the leading causes of stream degradation. The inputs of soil we send to our streams through ground disturbing activities like farming and construction, and scouring runoff that comes from hard surfaces like driveways and roads needs to be controlled. But small amounts of erosion and resulting sedimentation are natural processes, and the fine muds that form the bottom of these eddies are important in the continuum of stream habitats, from quiet muddy eddies, to violent bouldery rapids. Life has evolved and developed to nestle in a particular spot on the spectrum, and all habitats are essential. Even the muddy ones.
Tuesday, June 29, 2010
The water just upstream from the Shuresville road bridge over Deer Creek sporadically boiled as the early evening darkened. Must be shad I thought, and after a few minutes of looking, confirmed my suspicion: the shad had arrived to spawn, and their tails rapidly beat the shallow riffle into a boil. I needed to get into the water to witness this eons old rite from the perspective of these fish. Shad are in the herring family and are anadramous. Like salmon, they spend their lives at sea and endure an arduous spring journey as they swim inland to spawn in smaller creeks. Many shad are declining in number and some are endangered. Dams, which sever migration routes, and sediments, which cover gravel spawning beds, are the two current reasons for the ongoing lack of recovery.
The negative affect dams had on migratory shad was recognized early. The state of Pennsylvania has required fish passages on dams since the 1800s. Unfortunately, the passages installed were poorly designed and did little to restore fish migration routes. Even today, many passages are only marginally effective. A steady increase in the number of shad traveling through the Conowingo dam was celebrated in the years following the installation of a second fish lift, a kind of elevator that carries fish 100 feet up where they swim under route 1 into the water behind the dam. I thought shad were going to be the second fisheries success story of the Chesapeake Bay, behind rockfish. But then the numbers of shad passing through Conowingo significantly declined and demonstrated how interconnected all things are. Menhaden are an oily fish that are taken in huge numbers from the Chesapeake in what is effectively an unregulated fishery. They are turned into fertilizers and cosmetics and are a staple part of the rockfish diet. It has been theorized that as menhaden numbers decline, rockfish are eating more shad, which results in a decline in the number of shad making their way back up the Susquehanna.
Historically, ridiculously huge quantities were fished from our rivers. There are stories and pictures of a net strung across the entire mouth of the Susquehanna that captured a large part of the migration, back when we called these fish resources and thought they were inexhaustible. There aren’t any dams between this stretch of Deer Creek and the Atlantic, so shad can make the 175 mile journey from the ocean to this riffle unimpeded by concrete walls. These fish returned, driven by the primal urge to ensure their immortality by passing their genes on to the next generation. I want to witness this incredible act.
I slip into the water downstream of the shad and fight a heavy current. I don’t see any fish as I crawl my way against the flow. A fisherman from shore directs me to where the fish are spawning - a little further upstream and a little further out in the current. Ghostly blurs appear on my periphery as shad shoot past, then I feel a slap on my shoulder. I am right in the middle of the spawning school. I can barely hang onto the bottom against the current, and shad dart by with effortless but strong tail strokes. It is obvious their compressed bodies and powerful deeply forked tails make them perfectly designed for their reproductive task at hand. Silver tails flash over a particular spot in the stream bed just upstream, as females release eggs and males release sperm while fish continue to rush upstream. From above their olive backs make them invisible against the bottom. From beneath the surface their silver bodies are obvious through the early spring hazy water.
Shad are a kind of teleost fish which, based on the fossil record, first appeared 65 million years ago, so I figure shad have been making treks like this for 60 million years or so. And yet we might take them away in my lifetime. I feel fortunate to have experienced the timelessness of this event, timeless in relation to my fleeting human life span. Knowing these fish are here and spawning this year gives me hope that more will follow, and that maybe the great mythic shad runs I have heard of that occurred before I was born may once again fill our streams. And I hope that maybe my grand kids can snorkel with the descendants of the Deer Creek shad.
Friday, June 25, 2010
The Little North East turns from a piedmont stream, with lots of riffle and run sections to a coastal plain stream with a relatively gentle flow due to flat geography and sandy rather than rocky bottom, right about where it crosses under route 40. This section of stream was completely dug up for a sewer line to pass under the creek bed to a new pump station on the creeks northern bank two years ago. I slipped into the shallow water here below the route 40 bridge, and saw a large expanse of algae covered sand flat There weren’t any fish here. No crayfish. No obvious life except for the algal mat, not even any relief from the monotonous bottom, except for a few sandbags that remain as remnants of a coffer dam constructed for the sewer line routing effort. A large rimless truck tire loomed out of the distance, half buried in the sand. The continuous loud high pitched whine of a pump droned in the background, and gave the place an eerie industrial feel. I read accident reports that involved divers drowning after being trapped against water intakes, and while I was fairly certain this was the site of a pumping station and not a water intake, I was still nervous. The sandy bottom sloped off to a three foot deep hole with tree trunks and branches lodged against an old stump in the steeply cut bank. A school of pumpkinseed sunfish gathered near the wood. I’m fairly certain I saw the shadow of a small mouth bass swim off, and a calico colored sucker darted from the gravel bottom just as I passed over it, much like a stingray glides over the sand with one powerful flick of its wings. This stream is far from dead, and witnessing these fish lessened the industrial feel. Stringy brown strands of algae waved toward the surface as oxygen bubbles suspended them in the water. Even this sign of a degraded stream had a certain beauty about it and part of its attraction was that life could find a way in this used stream. Even the ugly and perceived dead streams, like Laurel Hill and this stretch of the Little North East have beauty. Some of that beauty is in witnessing how life finds a way. That life is here gives hope that we can work to restore the North East and Laurel Hill to a less degraded state than where it is now. And that is beautiful.
Thursday, June 24, 2010
Monday, June 21, 2010
I knelt in the 2 foot deep water and clouds of silt swirled from the bottom. The July temperatures meant that wearing a wet suit in this shallow, warm creek was thermal overkill, but I wished I had one on, at least to give me the impression of separation from what appeared to be a dead stream. Route 31 was to my back and I could hear the traffic bang across the bridge. I reluctantly put my masked face into the water and took a few hard breaths as I adjusted to the water temperature and stark view. The traffic noise was replaced with the sound of my breath rushing through my snorkel. Fine sickly grayish brown silt enveloped the bottom. The water was clear, but there was no life. Not even the usual thin algal mat that covers everything in many of the streams I have visited. The algal growth is a sign of eutrophication. Ecosystems, especially aquatic ones, need algae. They form the foundation of food webs. But too much algae create an unhealthy system. Algae are essentially a kind of plant. They are different of course since they have a hold fast instead of roots, but they serve the same role: they produce food that fuels the rest of the ecosystem. They need nutrients, specifically nitrogen and phosphorous, to grow. Too much nitrogen and phosphorous means too much algae. Most algae are short lived and when they die, they rob oxygen from the water as they decompose, which results in water that can’t support much life. The excess nitrogen and phosphorous come from us in the form of sewage, lawn fertilizer, farm fertilizer and car exhaust. Everything we do on land, and in the air affects fresh water systems and we are over fertilizing most of them on the planet, which causes widespread eutrophic conditions.
But Laurel Hill Creek didn’t even have that eutrophic algal mat growing in it. I crawled my way upstream along the bottom in a foot of water. Rock masses formed other-worldly shapes in this lifeless realm. No fish. I thought that I would at least see a sucker. Why was this rural stream in such a degraded state? I picked up a small rock and found a young crayfish. At least this stream isn’t completely devoid of life. The small crustacean took its time backing into its hole. A large disjointed dead crayfish claw lay near the base of another stone.
Rock, apparently imported to this stream for some construction project – maybe the route 31 bridge, littered the bottom, didn’t fit with the native geology, and gave the place a very strange artificial feel. A pipeline marker loomed out of the four foot murk. This stream was obviously harshly used. Finally I came upon a mass of brilliant green filamentous algae that rested like a large wad of cotton on a rock.
I returned to the stream later that night as lightning flashed in the distance, with the hunch that Laurel Hill Creek is loaded with crayfish. I was right. As soon as my light hit the water, dozens of pairs of orange reflecting eyes shone back. Laurel Hill creek isn’t all dead. There is life here, and the life here is just as fascinating as the life in a more pristine creek. But the question of why Laurel Hill is degraded remains, which will lead to the important answer of what can be done to restore the damage. Crayfish deserve better.
Sunday, June 20, 2010
I grew up on creeks.
I knew each rock, and every hole. I knew which rock held what crayfish. I knew where the big ones were. I knew the flood carved clay bottom that formed the deep hole that held the big suckers, at the end of the concrete channelized part. I would watch the rainbow gas and oil spill slicks bend and flow on the surface around rocks and down gentle riffles. The smell of diesel mixed with clay heavy mud as bull dozers and excavators straightened the stream and laid rock into gabion baskets to keep the creek in its channel, and to keep the channel from moving. And thanks to Mrs Beck, knew what the creek looked like before the houses were there, when the forest was intact, when the stream was allowed to act like a stream and flood its banks from time to time, and change the course of its channel.
Mrs. Beck lived in a Tudor style house the she and her husband Karl built from materials they harvested from the local forest and creek. Ruth and Karl Beck escaped Nazi Germany just before Hitler came into power and were the first to build in the woods off
Creek snorkeling is kind of an odd activity. Creek snorkelers spend as much time with their chest and stomach laying on the bottom as they do free floating. I’m sure it looks strange, but the views creek snorkeling provide far outweigh the odd look or two from passersby. Creek snorkeling gives me a completely different perspective on places I thought I knew. Streams I visited weekly for years from the surface, are completely new areas to me under water. Shallow depths seem greater, and what appear to be gentle flows while standing in them become more torrential when they are experienced in a prone position.
The world is different just below the surface. Its quiet, except for the rush of water pouring over rocks in a riffle. Time slows, and often seems to stop. At least the way I perceive time is different. Creek snorkeling puts me into the moment, and I don’t think about anything except what is before me at that particular point in time. I forget about where I am in the stream, and am surprised to see where I’ve wound up when I pull my head from the water. Sometimes what feels like great distances covered are really only a few feet. Creek snorkeling lets me get to know creeks from the perspective of the creek rather than the top side perspective of a human. I certainly feel much more connected to the stream after I snorkel in it than I do even after fishing or swimming in it.
I started this practice out of curiosity, just to see who is living just below the surface. I didn’t expect it to provide such an unexpected view. Every stream I enter is a very otherworldly realm - right there in our backyards. These seem to be places that we have largely ignored. It seems we have been too busy watching the other amazing places on the planet; coral reefs, the Amazon, to recognize that there are amazing places in our neighborhoods too. And I have discovered by snorkeling in streams, that one of those places is the local creek. I haven’t been on a creek snorkeling trip yet where I didn’t say wow at least once.