A TEMPORARY REFUGE
Natural History of a
Wild Summer Steelhead Refuge Pool
in the Western Cascades of Oregon
© Lee Spencer
The North Umpqua Foundation
All rights reserved
THE FIRST HALF
The pool that Sis and I sit at ceases to function as a refuge sometime in December . . . usually. This ending is due to a concatenation of many factors which appear to influence the wild summer steelhead into spreading fully, finally, through the basin of the main creek and probably elsewhere in the North Umpqua Basin as well. These many circumstances I am aware of are probably matched by many more of which I am unaware.
One of the fundamental considerations that moves the steelhead on their way is the full saturation—in particular—of the upper organic horizons of the soil; of the mycelia; of the roots, branches and bark and leaves or needles of the trees, shrubs, and other vegetation and the insides of these plants; the saturation of the insides and outsides of the metric tons of lichen carried in the forest canopy and coating the lower branches and bark of this vegetation too; and the filling of the pockets and reservoirs of the surface and subsurface bedrock and settling on the impermeable sediments. This takes a while and can be read between the spates by the level that the water achieves in the creek as it initially stabilizes, that is, when the creek is finally dropping by no more than half an inch a day.
The balance of the fish to whom the middle and upper reaches of this creek are home have more than likely left their other refuges in the North Umpqua River by this time and have arrived in this part of the main creek. Thus the entry into the pool for the first time by steelhead declines too. This could be considered a saturation of the creek by the summer steelhead.
During the generally increasingly frequent precipitation events of late autumn and winter, and the consequent spates, the steelhead go out from and return to the pool, but when the creek stabilizes at a level that is approximately two feet higher than the flows of late summer and early fall, the steelhead do not return.
This steady increase in the amount of water in the creek and the basin, however, merely makes leaving the pool possible for the steelhead. Other things may also signal that the time for leaving the pool and or spreading throughout the basin has arrived or is close anyway. One of these signals may be the ready state of the summer steelhead eggs and milt and the developed condition of the secondary sexual characters, that is, the accumulation of red skin pigment and snout growth which is most pronounced in the male steelhead. The decline of the path of the sun southwards across the sky, the shortening days, and the drop in temperature, probably each has its affect too. Certainly the smell of the water in the creek changes with the addition of the cast off leaves and needles and salmon carcasses. The smells of the creek probably also becomes richer and more complex with the initiation of flow again in those small headwater reaches that dried up during the past summer.
Possibly, even more ephemeral signals exist. One of the things about biological systems worth noting is that the apparent slightness of a signal is no guarantee of the relative magnitude of the effect on a given component of a system. An example of this is the trace element broth that forms the signal to a returning steelhead natal to a stream and that differentiates a certain stream from its neighboring streams or tributaries. It could be that even the changing sound of the creek may be a factor as the higher and faster flows expand the amount channel surface encompassed and shift larger and larger cobbles in the creek bed.
Occasionally, winters have long dry spells during which the creek levels fall significantly. When this happens, as it did during the winters of 2000/1 and 2004/5, then the pool refuge and other refuges may begin to hold fish again until the next creek rising precipitation event.
Once the steelhead go, after dismantling our camp and cleaning up the site, Sis and I leave too. This takes us three to five days and, during the six seasons we have been at the pool now, we have finally driven away from the site sometime between the 4th and the 19th of the month.
During December, the temperatures of both streams fluctuate slowly and together between the low thirties and the low forties, the lower temperatures reflecting gradual buildup of snow above three thousand feet in the basin, as well as, the occasional settling of polar air masses over the North Umpqua Basin; the higher temperatures reflecting the regular onshore movement of low-pressure systems from the southwest. In this part of the Cascades, snow at the elevation of the pool is commonly a response to the colder air from the north meeting the warmer marine air masses that are carrying more moisture. The fact that even in the absence of cold northern air, precipitation is normally stored as snow above three thousand feet gives to the creek a winter malachite hue, a shade of green-blue . . . when it isn’t flowing brown in the fluvial equivalent of the topsoil leaving the Midwest during the dust bowl. Now even the clearest water after two weeks without precipitation has a hint of a blue or green that appears to be integral to it. This was true of the creek in May and early June too.
Virtually every plant shows buds or new growth as was also true in late spring. Winter is the slow-growing season here in the Pacific Northwest, killing cold is kept generally at bay below three thousand feet by both the relatively near marine air mass and its on-shore movement and the presence to the east of mountain ranges, the Cascades and the Rockies, which block most of the continental polar air masses from reaching the coast.
By December the steelhead pod is holding in the lower part of the pool. Those steelhead that are active in occasional dominance displays do so ahead of the pod and at the middle of the pool, the area I called the arena in my first few seasons of notes. These dominance displays are mild and generally consist simply of lead fish positioning and/or jockeying.
During the three seasons that the steelhead and Sis and I had taken our leave of the pool during the first eleven days of December, no fish were present at this time. On the other three seasons, between 60 and 270 steelhead was the high count in the pool for the month. These moderate numbers reflect the fact that high creek temperatures and low flows are no longer holding the steelhead back from moving out into the basin above the pool. Generally by this time, several hundred steelhead have been counted in other holes within five miles upcreek from the refuge pool.
This pool remains a good staging area however and steelhead continue to use it while creek levels are not high enough to allow the steelhead to comfortably hold over their preferred spawning gravels.
Sometimes the steelhead continue to show an interest in holding quite high in the water column and will mill readily and sometimes the pod of fish will hold a few feet below the surface and relatively stationary. In either case, steelhead will leave and enter the pool with precipitation events that raise the water level. The next pool downcreek from the refuge pool is, more often than not, empty of fish by this time.
During the sixth season, in early December, the small group of three to three-and-a-half-inch young-of-the-year steelhead continued to frequent the relatively still water in the lower right pool.
Now sometimes, the cutthroat trout are holding with the steelhead pod and sometimes holding separately in small groups in the eddies out of the main path of the currents that move down through the pool. When present in the eddies, these groups of cutthroat trout are often holding furthest from the main creek flows and are therefore faced downcreek. Note that, no matter whether the eddy in clockwise or counter-clockwise cycling, that portion of the eddy nearest the bank is always flowing in the opposite direction from that of the main creek.
While there seem to be consistently fewer per capita approaches to items than was true earlier in the fall, the wild summer steelhead do continue to show more interest in approaching things in the flow than they did during the first few months of the season. This interest, this acting out of what I believe to be primarily curiosity, continues to focus on non-food items such as leaves, twigs, and bits of lichen, as well as on insects or other items that are potentially recognized by the steelhead as food.
It must be asked though, what is and what isn’t a food item may have been confused by a mature steelhead’s time in the ocean, a place where they grew relatively many times larger than they were as fry living and feeding in the stream. Is a broad-leaved maple or an alder leaf the same size to a mature steelhead that a medium-size mayfly was to it when it was less than a year old and living in the main creek?
One insightful steelhead researcher states that the longer a steelhead remains in freshwater, the more likely it is to find food in its stomach. This generally fits with what Sis and I see in the way of changes in steelhead approach behaviors in the pool and in the creek. However, while approaching and taking caddis flies or mayflies, larvae or adults, may in fact represent feeding in steelhead, it cannot represent functional feeding because there is not enough nutrition available in any creek or river here in the Pacific Northwest to keep the various populations of adult Pacific salmon alive if they needed to eat. These adult salmon are simply too large for the fluvial systems to support them.
The ocean, on the other hand, is comparatively such a rich environment that not only do steelhead put on four to six pounds a year while living there, but they are able to amass reserves of fat that will carry them through a migration and a spawning process that may last the largest part of a year without feeding. No freshwater river in the northern temperate zone has anywhere near the amount of productivity that the marine environment displays.
Whether these reserves will carry a summer steelhead back to the ocean is another thing altogether. An increase in the difficulty or the length of their journey may make significant inroads on ocean-derived energy reserves. These difficulties include but are not confined to a particularly hot summer, being hooked and fought once or more than once, having a hard time finding a suitable partner, or a sustained spooking event such as what a wild fire. It is possible, however, that a certain amount of incidental feeding on those resources available in freshwater may sometimes represent the difference between getting back to the ocean or not doing so for a steelhead.
As with all of Nature’s stories that I am even somewhat familiar with, successful productive natural systems, including populations of wild steelhead living in their multiple environments, do not subscribe to human concepts of tragedy or for that matter comedy either. The fact that most steelhead do not survive to return to the ocean after spawning has its adaptive advantages, as odd as this may seem to any creature that knows its own mortality and, thus, the fact that it is not immortal. Most of the Pacific salmon species have adapted or evolved in such a way that they don’t survive the spawning process.
The incorporation of ocean-derived nutrients into a stream by the death and the decomposition of parental carcasses of the chum, pink, sockeye, coho, and chinook species has obviously been determined by evolutionary processes to be more advantageous to the various populations of these species than some level of spawning survival and return to the marine environment. It is probable that death after spawning for these species has been adopted as a population survival strategy because, to name one of the more obvious results, their death after reproduction fertilizes the stream environment—including the estuary—local to their redds. This fertilization with marine-derived nutrients creates a tremendously richer environment by the time the young-of-the-year are out of the gravels. To a significant degree also, death after spawning makes room in the finite pastures of the ocean for their offspring, the very small percentage of highly resilient wild Pacific salmon smolts that survive their time in the very uncertain natural streamflow environment.
It could be argued that the ability to amass sufficient reserves by marine feeding to carry the adult Pacific salmon through their spawning processes, but not necessarily through a return to the ocean, has been taken advantage of quite successfully by the Oncorhynchus genus. As I've stated above somewhere, the chinook, coho, sockeye, chum, and pink salmon, historically attained much higher biomasses in the north Pacific than did the cutthroat and rainbow trout (Oncorhynchus clarki and mykiss, respectively). What researchers have shown in their studies of the life habits of cutthroat and rainbow trout is that, with the possible and specialized exception of the sockeye, these trout have retained much more complex ties to the freshwater environments than have the other Pacific salmon.
Virtually all of the deciduous leaves have fallen by this time . . . with some exceptions. There is often a single green leaf remaining to each alder. A few yellow leaves are retained by willows and taller cascaras, and there are fewer of the many-colored dogwood leaves and more yellow ones. By now the shortened amount of daylight has been maximally mitigated by the amount of sky visible and the amount of light that gets to the ground among trees.
The birds that will be around all winter are present at the pool. The more common of these birds are the winter wren, dipper, kingfisher, kinglets, chickadees, nuthatches, pileated woodpecker, raven, possibly the jays, hermit and varied thrushes . . . and blue herons. There is food enough in the various environments of the Western Cascades to support these various bird species.
As I was writing this passage an unusual behavior, among many, of the dipper occurred to me. I have yet to see one of these ouzels perch on a branch of any tree or shrub. They land on water, drifted woody debris, rocks, and sediment regularly but never living branches in my experience. Undoubtedly, others have seen them perched on branches, but the fact that I haven’t in my life so far, and especially in my last six years on the pool, suggests that this is not a common thing.
Perhaps . . . No, there are plenty of branches to go around.
Occasionally, this time of year, unusual sightings of birds happen. During early December of the fourth season four hooded mergansers were around this part of the creek for about a week. These birds visited the pool over a two-day period and fished assiduously while in view.
By this time, I only rarely see the common merganser and when I do they are usually in swift whistling flight up or down the creek. The dramatically marked male mergansers are now and then once more present in the basin of the North Umpqua River.
Chipmunks are not true hibernators unless, perhaps, they live in areas where thick snow commonly blankets the ground during the winter. This is not the case at the pool. Periodically during the winter, these creatures will rouse from their seasonal dozing to eat foods that they have gathered and cached during the summer and fall. On warmer days during the winter they may be active above ground.
Otters are active year round and may show up in the pool at any time. The family groups that have held together for most of the season are about to split up and go their way according to my reference texts. The female otter carries sperm that was implanted in the late spring and will soon be allowing it to fertilize one to four of her eggs.
In December, veritable blizzards of insects continue to occupy the air over the creek when the sun is out. A certain number of these insects would be out regardless of the weather, but the sunlight unquestionably increases the number of different species that are out and definitely makes them more visible. Autumn caddis, mayflies, and crane flies continue to be among the insects that always seem to be about.
As I have said earlier in this chapter, Sis and my time at the pool is either over or about to be so. It takes several days to take down the viewing area furniture and tarps and those of our camp on the flat above the pool. My friends, Mike and Elsie Marchando or Marv Husen, come and tow the trailer down to the area of the Steamboat Inn for storage. Sis and I say our goodbyes and go to the place where we will spend the next month or two in relative seclusion while I begin my early winter work with an initial transcription of the natural history notes taken during the season just past. These notes may be said to form the nutrient base for this book; the steelhead and their interactions with their environment form, therefore, my ocean.
The steelhead? When Sis and I go, they have already gone. By December, the time of summer steelhead needing their refuge is over on an average year. The warm waters of summer are long gone and the sun has retreated into the southern part of the sky so shadows are on the creek for much of the day. With the regularizing of the rain events and the gradual saturation of the Pacific Northwest environments, the uneasy writhings of its streams as they grow and settle into their enlarged winter beds is about done. The summer steelhead are on about their affairs which are to find the various expanses of spawning gravels native to the local breeding population they belong to.
Once they have decided on a particular set of gravels in the tail of a particular pool or in front of a boulder or partially buried piece of large woody debris in a riffle, these steelhead will wait around for a few weeks longer while they engage in sexual selection behaviors in proximity to these gravels. Having exhibited appropriate sexual selection behaviors to each other, a given pair of summer steelhead will spawn, probably in February or March. If the fish in question is a larger male, it may continue to wait around for other spawning opportunities. Her eggs shed, her redds covered and now become moundings of particularly clean streambed gravels, the female steelhead—regardless of her condition—will start on her way back to the ocean. If she is in good enough condition and avoids being caught and killed by anglers, she will make it to the ocean and begin substantial feeding once more. It must be a relief, like the water of a large cool spring after a long dry hike in the desert.
The lives of the summer steelhead after they leave the pool are another story and one that is equally important to that of their time spent in their seasonal refuge in the middle of the main creek basin. It is a story however, that has yet to be documented in more than a piecemeal way by Sis and me.
What is known is that when these summer steelhead no longer gather in the large numbers they do in their main refuge pool, once they have spread throughout the middle and upper portions of the main creek basin, they are no longer in need of the simple services Sis and I render them here at the pool.
At the time of this writing, angling regulations on the North Umpqua River allowed people to kill wild steelhead—one per day, five per year—between January 1st and April 30th. In 2007, this changed and no wild steelhead were allowed to be kept during the winter. The local ODFW office is on record as supporting the killing of wild fish in the winter and this conservation regulation is under review by the State Game Commision.
Regardless of this regulation, any summer steelhead that has survived spawning must run the fishing-and-playing-out gauntlet on its way back to the ocean.
Take care, go well,
Lee and Maggie