The Odd and Magnificent Prickly Sculpin

Cottus asper. (c)RiverWhy

Cottus asper. (c)RiverWhy

I stopped today at my favorite local reptile store to pick up various forms of live food for my ever growing zoo of fish and amphibians. I was asking for feeder fish, which are used to feed animals that refuse pellets or flakes. The man who was helping me asked what I was feeding. I replied “sculpins” — I have four of them living more or less peacefully in a community tank with two non-native green sunfish and some platys. At my reply, the man uttered, “hm”, and turned away to fetch my order. I figured he was not very interested in my fish, and somewhat gruff, like many of the folks who work there. Reptile people can be a lot like bartenders; the surliest ones are often those who tend to make the best drinks. I appreciate both reptile people and bartenders for this.

When the man brought my feeders back, he placed the bag on the counter and said something utterly unexpected. “When I was a boy in the UK”, he said with a big smile, “my favorite book was about a lobster whose only goal in life was to walk on land. His best friend was a grumpy sculpin. I’ve never forgotten that book, and every time I think of sculpins, it makes me a little choked up.” His gruffness was not gruffness at all. I told him I would bring a picture of my kids (the sculpins) back to show him, and he said that was all right, as long as I didn’t mind him getting teary-eyed if I did.

What is it about that love for something so common, yet so extraordinary, that stays with a man for his entire lifetime?

A great many people will never know what a sculpin is. My variety are called prickly sculpin, Cottus asper, and they are native to streams and lakes throughout the Pacific slope watersheds. They belong to the superfamily Cottoidea, encompassing over 750 distinct species all over the world. They are called prickly sculpin because of the rough texture of their skin when felt with a finger moving toward the head, similar to a cat’s tongue. Benthic fishes, they are skilled predators, striking lightning-fast after bugs and small fish on the stream bottom. And they stick to the bottom like glue; you’ll hardly ever see them in the mid to upper water columns. They are weird-looking, maybe even ugly; their faces make me think of a fat man behind the counter of a gas station in South Dakota with a stained T-shirt and a cigarette hanging out of his mouth, leaned back in his chair and leering at you, trying to decide whether you’re going to try and steal that bag of Funyuns. They’re gruff and grumpy as the best San Francisco bartenders. But as odd-looking as they are, there’s something alluring about them.

Prickly sculpins, and their cousins riffle sculpins, are not tolerant of poor water quality, so they’re one of the fishes we lose in urbanized watersheds with high pollutant load, artificial stream features or poor aquatic habitat. As predators, they demand a fairly high level of habitat intactness that will produce enough smaller critters for them to consume. I never remember seeing them as a kid, though I spent a lot of time in the streams of the Bay Area. I first handled one only a few years ago, doing stream surveys in East Alameda County, and recall distinctly how magical it felt to meet this new creature.

Most people revere trout as the ultimate stream fish; the vision of a leaping steelhead, shining in the light before splashing down into a rocky stream, is their aesthetic ideal. But prickly sculpins are my favorite stream fish. I think they’re perfect; the combination of their beautiful mottled coloration and their grumpy faces is just right. I love that they are neither perfectly beautiful nor perfectly ugly, but an intriguing balance of the two. It’s nice to know the sculpin man at the reptile store loves them, too.

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Streams, snorkels, and golf courses

image1Today we were out testing a new survey method on a reach of a stream that we typically survey via electrofishing. Snorkel surveys basically consist of putting on a wetsuit (16 degree Celsius water is cold for us warm blooded critters), grabbing a snorkel and an underwater flashlight and poking into the pools to identify and count the inhabitants. It is a much less invasive survey method than electrofishing, in which an electrified probe is stuck into the water that shocks the fish so that they can be netted, measured and weighed. The fish are returned to the water afterward, but when we’re working with already stressed populations we like to use a less invasive alternative. This particular stream has totally dried up in sections for several years in a row due to the drought, so the fish have no choice but to oversummer in the remaining pools. So far, the pools have been expansive enough and the water cool enough that we have not lost our populations of native trout (Oncorhyncus mykiss) and California newt (Taricha torosa). But there is great concern for the viability of the populations.

A popular hiking trail runs right alongside this creek, and despite signage asking folks to keep their pets out of the water, dogs are constantly jumping in and disturbing the critical oversummering pools. These fish are evolved to endure prolonged drought, hunkered down in the oversummering pools. What they are not evolved to endure is dozens of dogs invading and disrupting their pools day after day throughout the dry season and causing water turbidity to go through the roof. Turbidity lowers dissolved oxygen (DO) content, making it more difficult for critters with gills to breathe. So, when we started our annual population surveys, we decided not to electrofish to avoid adding another stressor to these already stressed populations.

The survey was hearteningly successful, and the pools fairly ample and deep throughout the reach. But this is due to a surprising cause. There is a golf course upstream of this reach that, due to the watering of the turf, creates an additional groundwater input that augments the streamflow. Who would have thought that golf courses could be beneficial to fish? It’s a fascinating example of reconciliation ecology – anthropogenic (human) activity actually benefiting wildlife instead of harming it. We don’t know for sure, but there is a chance that if this golf course did not exist, we would not have found any viable pools at all. While more a happy accident than a purposeful act of conservation, it is certainly an important factor to be considered when planning species conservation efforts in a watershed heavily impacted by other human activities. In areas where humans have altered natural dynamics so drastically, nature needs all the help it can get.

River Physics

river.0Rivers meander in much the same way that snakes slither—their forward movement is not only lateral but also longitudinal. A time-lapse map of a river’s channel is like the revealing of some great, ancient secret. The simple movement of water through the landscape is one of the most powerful forces on Earth.

Rivers and streams are fascinating, deeply complex creatures. They are hugely influential ecological pathways, contributing to essential ecosystem processes both above and below the surface. The critical watershed-scale work of the river is to transport a balance of water and sediment downstream to the receiving water source (ocean, lake, bay, et cetera). The ecosystem processes that spring from that single task are enormous in scope and are critical to a large majority of California’s wildlife.

The geomorphic characteristics of watersheds change dramatically from their headwaters to the river mouth (geo = earth, morph = shape, form). The word “geomorphology” describes the behavior of the physical structure of rivers and the study of that structure. The upper reaches of streams are composed of large boulders and very steep slopes, and are tightly confined within their valleys. The action of water on this rock, the river’s substrate, is partially responsible for the creation of the sediment-water balance. Because of the steepness of these mountain streams, their channels are typified by a step-pool structure with very little meandering. This is the reason that mountain streams are clear, clean, and unusually musical.

Where these steep valleys open up, a new source of sediment joins the river—bank sediments created by the natural erosive process of meandering. Rivers that are allowed to move freely within their meander belts are continuously eroding and rebuilding their meanders. A river can meander while still remaining confined to its valley because, in its snakey movement, erosive energy is transferred downstream as well as laterally.

flickr_looping_amazon_river_2These middle areas of the watershed both collect and deposit sediments; they are deposited in the form of point bars, which form the inside of a meander. A well-sorted point bar, with fine sediments higher on the bar and progressively coarser sediments toward the active channel, is one sign of a healthy river. This process occurs because the slower water is moving, the more sediment it will drop out of suspension. When water slows down on the high edge of a point bar, the sands and silts drop out; in the thalweg (deepest point of the channel) fast water will roll larger bed material downstream while maintaining its suspended sediment load. Rivers in equilibrium will not excessively erode nor aggrade their sediment. Rivers out of equilibrium—well, we will hear much more about those later.

Finally, in the lower reaches, rivers begin to branch out into tidal marsh complexes typified by very fine, rich sediments and braided channels. Nearly the entire San Francisco Bay was once bordered by vast expanses of tidal marsh. Tidal marshes provide both critical ecosystem processes and benefits to human communities, including nutrient and pollutant filtration, carbon sequestration, and flood mitigation. Intact marsh complexes actually protect coastal communities from storm surges—a fact powerfully demonstrated by Hurricane Katrina.

This incredible process creates beaches and nourishes tidal marshes and the biotic community that relies on riparian corridors—not only in California, but in watersheds around the world. There is something about the universality of river physics that is both electrifying and oddly comforting—that even if the river is damaged, the stream channelized, the energy is still out there somewhere, waiting for its time to go to work once again.

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Credit to Flickr: leoffritas (Creative Commons 2.0) and @josephstromberg at Vox for the super cool imagery.

What is nature for?

11225072_10207160433190570_7063498719917835900_nAn apprentice of mine, in his entry interview, upon being asked why anyone should care about nature, replied after only the slightest hesitation, “Well – because it’s the most beautiful thing there is.” This has gone down in history as possibly the best interview answer ever uttered.

Beginning this tiny insignificant dot of a blog, at the beginning of my thirteenth year as a restoration ecologist, I wonder, near-constantly, what nature should mean to a person. To a people. To all people. Increasingly, it seems that we’re no longer a part of it. That we’re drifted off into a universe entirely of our own making – a universe essentially devoid of the wonderful chaos of a system governed by the laws of nature rather than the laws of man.

Yet wonderful things happen when those who have been disconnected from the natural universe check back in. Despite the fact that I’m an insufferable curmudgeon, some of my greatest satisfaction has come from sharing my love of the natural world with others. The young people I work with are among my greatest inspirations. I can’t say there’s hope, exactly; often there isn’t. Often there is the exact opposite of hope. But I think a life lived in awe of the natural world, in constant curiosity, in the pursuit of both understanding and beauty, cannot be a life wasted.

I would want everyone to care about our natural world enough to wonder how it works, why it is there, and what it means to them personally and to us, the human race. To wonder, and then to discover.

I suppose this blog, then, is to speak to anyone willing – anyone wondering – what nature is for, what it means, what it can give – anyone questioning the relationship of humankind to nature — to wade through the muck at the edge of the floodplain – to take in the sounds of the wind in the trees, the insects moving, the splash of water – to move toward the water’s edge.

To part the reeds, and to prepare to be quietly amazed.