University of Washington
University of Washington
The Puget Sound Basin and Salmon: Developing a Scientific Basis of Understanding
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Week 1 - A Puget Sound PrimerRequired ReadingRalph Haugerud and Tom QuinnJanuary 6, 1999The Lay of the Land- Ralph Haugerud A Salmon Primer- Tom Quinn
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| Pliocene (2 - 5 Ma) |
no known outcrops | ||||||
| Miocene (5 Ma - 23 Ma) |
A few outcrops of fluvial conglomerate, sandstone, and siltstone
Deposits we see are about 15 Ma old |
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| Oligocene and latest Eocene (24 - 40? Ma) |
To west (margins of Olympic Peninsula, Bremerton): marine (continental
shelf) sedimentary rocks To east (Issaquah) nearshore sedimentary rocks |
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| Eocene (40? - 57 Ma) |
Two provinces: On west, mostly marine basalt (high peaks of eastern Olympics, Black Hills) and overlying marine sedimentary rocks On east, fluvial sandstone (Green River gorge) and associated andesitic volcanic rocks (quarries SE of Issaquah and N of Southcenter) |
Note that:
Cascade arc volcanoes began erupting about 35 Ma ago, a result of a change in plate motions in the NE Pacific region that occurred at 42 Ma. The regional tectonic regime has been roughly similar ever since.
There is indirect evidence for uplift in the vicinity of the Olympic and Cascade mountains as early as 15 Ma, but we do not know that the mountains were as high then as they are now. The mountain ranges to the east and west of the Salish Lowland may be mostly younger than 15 Ma.
The first glaciers in the Salish Lowland, some 2 Ma ago, probably flowed across a pre-existing topographic low. Deposits in the lowland record at least 6 glacial episodes, each lasting (by analogy with better-studied deposits elsewhere) thousands to tens of thousands of years. We know little about the details of the first 5 glaciations, but presume that the much more accessible deposits of the last glaciation record a process that occurred many times before.
Composite stratigraphic section for glacial deposits of Puget Lowland (37 kb)
The last (Fraser) glaciation began about 25 ka and lasted until about 10 ka. The early phase of the Fraser glaciation, known as the Evans Creek stade from deposits SE of Seattle (near Vancouver, BC it is called Coquitlam) was protracted alpine glaciation, with ice growing in the Cascades and Coast Mountains and forming valley glaciers in the mountains. Evans Creek ice may have locally reached the margin of the Puget Lowland. After about 18 ka, ice began advancing south across the Salish Lowland from sources in the Coast Mountains, the interior of British Columbia, and the North Cascades. This ice advance is known as the Vashon stade. When Vashon ice reached the latitude of Seattle (after 15 ka), Evans Creek ice had retreated, and Vashon ice blocked the west-draining valleys of the Cascade Range.
When Vashon ice reached the NE corner of the Olympics, it blocked the Puget Lowland and turned the lowland into a large lake. Glacial outwash filled the lake with clay and silt, then sand as the ice grew closer. As the lake filled it was converted into a floodplain, floored with coarse alluvial deposits carried by rivers flowing off the ice. The lake in front of the Vashon lobe, and the rivers that replaced it, drained south via Black Lake near Olympia into the Chehalis river and thence to the sea. The modern lower Chehalis River is now underfit--the present stream is too small to have carved its valley.
The proglacial lacustrine and alluvial deposits were then overridden by the ice sheet, the whole depositional stack sculpted by flowing ice and running water at the base of the glacier, and the deposits immediately beneath the glacier churned into a few meters thickness of glacial till. As the ice wasted away, rivers flowing across the bare landscape quarried and redeposited large amounts of debris.
Vashon ice was short-lived! Seattle was ice-free at 15 ka, ice-covered afterwards, and ice-free again by 13.5 ka. Ice retreat was especially rapid, probably because as the ice thinned it reached a critical thickness in the Strait of Juan de Fuca and floated, retreated eastward by calving, and the ice sheet remaining in the Puget Lowland was beheaded. Ice lingered longer in the Fraser lowland; the youngest glacial deposits there date to about 10 ka.
Southern Cordilleran Ice sheet at Vashon maximum (50 kb) from Clague (1994)
Details of the southern margin of the ice sheet at the Vashon maximum (81kb) from Booth and Goldstein (1994)
Time-distance diagram for Fraser glaciation (38 kb) from Clague (1991)
Another view of time-distance relations for Vashon stade of Fraser glaciation (29 kb) from Booth and Goldstein (1994)
The result was the following stack of deposits
| Recessional outwash | Bedded and sorted sand, gravel. Deposits of rivers flowing from wasting and retreating ice |
| Till | Unsorted mixture of clay, silt, sand, gravel, cobbles, usually no more than a few meters thick. Debris churned beneath flowing ice |
| Advance outwash | Bedded and sorted gravel and sand at top: Deposits of rivers flowing
from advancing ice well-bedded clay and silt at base: Deposits of lakes (or salt water) farther in front of the ice |
The most abundant material by surface area in the Puget Lowland is till of Vashon age. (South and east of Tacoma there is extensive recessional outwash.) However, the till is commonly a thin veneer, and the majority by volume of the Vashon-age glacial material in the lowland is advance outwash.
Our landscape can be decomposed into the following elements, going
from the most fundamental to the least--imagine a crude Fourier
analysis of the topography:
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| (0) the hole between the Olympics and the Cascades |
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| (1) Boothian Plain Puget Lowland is mostly a young flat surface several 10s of meters above present sea-level, an old valley bottom. This was recognized only recently, by Derek Booth, a geologist now on the Civil Engineering faculty here at the UW |
deposition by streams flowing off advancing Vashon ice | 17,000 - 15,000 ybp* (Vashon advance) |
| (2) big troughs (2.1) flat trough floors Examples are Admiralty Inlet, Hood Canal, Lake Washington, the Kent Valley. Locally the troughs have been filled in by modern rivers (and debris flows coming off volcanoes to the east) |
sub-glacial erosion (fluvial?) post-glacial deposition |
15,000 - 13,500 ybp* (Vashon) 13,500 - 0 ybp* |
| (3) ice striations Look at a detailed topographic map of the Lowland to see pervasive, mostly N-S striations, typically with meters to 10s of m of relief. These striations are much of the reason why cross-town travel in Seattle is so difficult |
moving ice | 15,000 - 13,500 ybp* (Vashon) |
| (4) undulations The Boothian plain isn't really that flat. In many places there are gentle, roughly E-W lows that for want of a better word we can call undulations. An obvious example is the natural low followed by the Seattle Ship Canal (connecting Lake Washington, Lake Union, and Puget Sound) |
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15,000 - 13,500 ybp* (Vashon) |
| (5) gullies, beach bars, landslides, ... Think Piper Creek, Ravenna Creek, Ediz Hook, Golden Gardens, Perkins Lane |
post-glacial erosion and deposition | 13,500 - 0 ybp* (Holocene) |
* ybp =radiocarbon years before present. Not calendar years; exact correlation is uncertain. 15,000 radiocarbon years before present is about 18,000 calendar years ago. The variation is primarily because of temporally varying, and uncertain, rate of production of radioactive carbon by cosmic-ray bombardment.
Landforms 1, 2, 3, 4 were all formed during last (Vashon) glaciation, between about 15,000 and 13,500 ybp. There are few--beyond the lowland hole--pre-Vashon relicts.
Landforms that reflect processes acting now are 2.1, flat floors of big troughs and 5, small gullies that dissect edges of region and local beach bars and spits, landslides, etc.
Glaciation greatly re-arranged the drainage network in the Pacific Northwest.
The evidence for the process is clearest in the eastern North Cascades, north of Winthrop, where there is an east-west drainage divide just south of the border. Vashon-age ice advancing south from British Columbia dammed north-flowing streams tributary to the Similkameen River. The resulting lakes spilled over high passes to the south. Fluvial erosion lowered the passes and moved the drainage divides to the north. Primary evidence is extensive fluvial scour and coarse fluvial debris in south-draining valleys tributary to the Methow River, and lake deposits in north-draining valleys immediately to the north. The process must have been repeated during each glacial cycle, perhaps at least 6 times during the course of the Pleistocene.
The most conspicuous drainage re-arrangement in the eastern North Cascades is the erosion of a former divide north of Mazama, incision of the Lost River Gorge, and addition of about a township (circa 100 km2) of formerly north-draining area to the Methow drainage. The Lost River Gorge is a spectacular trail- and road-less box canyon nearly 1500 m deep. On the 1:100,000 scale map, 250-m index contours disappear under overhangs on the canyon walls.
Less clear, but still convincing, landform evidence indicates that prior to Pleistocene glaciation (before 2 Ma) the west-flowing Skagit River was a short stream similar to the modern Baker River or Cascade River, starting at a north-south divide near the site of the present Gorge Dam just upstream of Newhalem. The upper Skagit River drained north into British Columbia until a proglacial lake--dammed by south-advancing ice--spilled over a pass along the then-Cascade Crest in the Gorge Dam area and incised the Skagit Gorge.
But the biggest Pleistocene re-arrangement of them all is the Fraser River. On the east side of the Coast-Cascade mountains, northeast of Hope, BC, several-million-year old main-channel gravel deposits record the existence of a former north-flowing Fraser River. West of the Olympic Peninsula, the Nitinat deep-sea submarine fan--whose sediment comes from the Strait of Juan de Fuca--appears not to have existed prior to about 2 million years ago. The obvious conclusion is that prior to the Pleistocene (circa 2 Ma), most of the interior of southern British Columbia--the present upper Fraser drainage--was tributary to the Peace River, which flows through the northern Rocky Mountains and thence east and north to the Arctic Ocean via the Mackenzie River. The present continental divide--at Summit Lake, north of Prince George, B.C.--is a swamp that Alexander Mackenzie and his companions paddled (and portaged) across in 1754, during the first European traverse of North America north of Mexico. Prior to the Pleistocene, the continental divide must have been near Hope, B.C., at the crest of the Coast Mountain-Cascade Range crest.
Sketch map of NE Pacific, showing Nitinat submarine fan (73 kb) from McKee (1972)
There have been more recent, though minor, changes in the drainage network around Puget Sound. Prior to digging of the Montlake Cut, in the early 1900s, Lake Washington and all the streams tributary to it drained into the Duwamish River via the Black River at Renton. In the late 1800s, the White River (southeast of Auburn) at times flowed south into the Puyallup, and at other times flowed north into the Duwamish, changing course as various logjams were rearranged by floods or dynamite. Its present course (into the Puyallup) reflects the will of King County farmers who had more dynamite than their brethren in Pierce County. Farther north, at the Skagit-Whatcom County line, the South Fork of the Nooksack appears to have recently (to a geologist) flowed south into the Samish River--though there is no historical record of this.
You should understand better than I what the consequences of this geology, geomorphology, and drainage history are for salmon in the Puget Sound basin. I am not a fish expert. But I will hazard a few suggestions:
Much of the Puget Sound basin is dominated by till and advance outwash. There is relatively little near-surface bedrock. One might suspect that groundwater flow is more important than in basins in SW Washington and on the east slope of the Cascades.
Unlike most landscapes, ours is not primarily river-carved. Low-elevation, moderate-relief areas are more extensive than in comparable salmon-bearing drainages outside the Salish Lowland (Coastal Oregon and SW Washington, east slope Cascades, northern BC coast and SE Alaska).
The Puget Sound basin didn't always look like it does now. There were no salmon in Puget Sound 14,000 (radiocarbon) years ago! Two million years ago, the upper Skagit River didn't drain to Puget Sound and most of the present Fraser drainage was tributary to the Arctic Ocean or Hudsons Bay.
I have not attempted to thoroughly reference the above mixture of fact, inference, speculation, and opinion. The best single paper on the salmon geology of the Puget Lowland is probably:
Booth, D.B., and Goldstein, B., 1994, Patterns and processes of landscape development by the Puget lobe ice sheet: Washington Division of Geology and Earth Resources, Bulletin 80, p. 207-218.
WDGER Bulletin 80 contains other articles that summarize regional geology and provide a point of entry to the literature. Some of you may also find it interesting to look at
Thorson, R.M., 1989, Glacio-isostatic response of the Puget Sound area, Washington: Geological Society of America Bulletin, v. 101, n. 9, p. 1163-1174.
Clague, John J., 1991, Quaternary glaciation and sedimentation, Chapter 12 in Geology of the Canadian Cordillera, H. Gabrilse and C.J. Yorath, editors: Geological Survey of Canada, Geology of Canada, no. 4, p. 419-434.
Clague, John L., 1994, Quaternary stratigraphy and history of south-coastal British Columbia, in Geology and geological hazards of the Vancouver region, southwestern British Columbia, J.W.H. Monger, editor: Geological Survey of Canada, Bulletin 481, p. 181-192.
Easterbrook, Don J., 1994, Chronology of Pre-Late Wisconsin Pleistocene sediments in the Puget Lowland, Washington: Washington Division of Geology and Earth Resources, Bulletin 80, p. 191-206.
McKee, Bates, 1972, Cascadia: The geologic evolution of the Pacific Northwest, New York, McGraw Hill, 394 p.
Meany, Edmond S., 1923, Origin of Washington Geographic Names, Seattle, University of Washington Press.
Key Themes in the Biology of Salmon, Trout and Char
Tom Quinn: School of Fisheries, University of Washington
1. Anadromy:
Spawn in freshwater, migrate to sea to grow, return to freshwater to spawn. This life history pattern leads to large size at age and high density of salmon, relative to non-anadromous salmonids.
Exception: non-anadromous forms.
2. Homing:
Spawning almost invariably occurs at the natal site. This trait leads to the evolution of populations that are distinct as genetic entities and production units.
Exception: straying.
3. Semelparity:
Death inevitably follows reproduction in the "traditional" North American Pacific salmon. This results in transfer of marine-derived nutrients to freshwater ecosystems.
Exception: iteroparity
Notable Life History Traits of Salmon and Trout
1. Pacific salmon spawn in the fall whereas most freshwater fishes (including rainbow and cutthroat trout) spawn in the spring.
2. Salmonids have large eggs, producing large fry.
3. Parental care (egg burial ) is provided by the female.
4. Juveniles use freshwater habitats, especially streams (coho and chinook salmon, rainbow and cutthroat trout) where they eat insects and lakes (sockeye salmon) where they eat insects and zooplankton.
5. Use of estuarine habitats is less prevalent among species with large smolts (e.g., steelhead, coho) than those with smaller smolts (chum and ocean-type chinook).
6. Marine life is spent in the epipelagic coastal and offshore waters, feeding on a diverse diet of zooplankton, macro-invertebrates (e.g., krill, squid). Growth is very rapid
7. Salmon populations tend to be very productive, thus can support high fishing rates and would otherwise experience strong density-dependent controls on spawning or rearing life history stages.
Life History & Distribution of Oncorhynchus, Salmo and Salvelinus
Oncorhynchus:O. gorbuscha (Russian name for humpback): pink salmon (humpy). Range in North America from the Sacramento River to Mackenzie River but scarce south of Puget Sound (except for a Sacramento River population) and in the arctic. Also in Russia, west to the Lena River and in Hokkaido, Japan. Most abundant salmon species. Two years old at maturity (except Great Lakes where there are 3s, 4s and apparently some 1 yr old males). They produce small eggs (about 5 mm) and seaward migrating fry (= smolts, about 29-33 mm). They display an offshore (rather than coastal) marine distribution. Average adult size about 2 kg (range 0.5-6.0). Very dramatic sexual dimorphism, especially a large dorsal hump in males. Two year cycle leads to on-off temporal distribution. Generally, even years dominate in Queen Charlotte Islands and Alaska whereas odd years dominate in Fraser River, Puget Sound and southern waters. Odd years also dominate in Asia. Generally spawn in the lower reaches of rivers. Adults at sea identified by small scales and large, somewhat indistinct spots on the tail and back.
O. keta (Russian word for salmon): chum salmon (dog). Range in North America from Sacramento River (but scarce in California) into the Arctic Ocean (Mackenzie River). In Asia: west to the Lena River and south in Russia and Japan. Typically mature at 3, 4 or 5 years of age. Eggs are large, about 5-6 mm. Fry emerge at about 32-38 mm (generally larger than pinks) and may reside in the stream for a few days or weeks. Then they go to sea, use estuaries in many cases, and their oceanic distribution is offshore. Size: about 5-6 kg (said to reach 20 kg). Generally spawn in the lower reaches of rivers soon after leaving the ocean but populations migrate over 2000 km up Yukon, Mackenzie and Amur rivers. Less abundant than pink and sockeye salmon. Adults at sea do not have spots but have irridescent pigment in the form of "rays" on the tail.
O. nerka (Russian name): sockeye salmon (red in Alaska, blueback on Columbia River). Range in North America from Klamath River, California to Point Hope, Alaska but currently from Columbia River north. In Asia, from northern Hokkaido to Anadyr River but 90% from Kamchatka Peninsula. Eggs are small, 4.5-5 mm. Fry are small, usually about 25-29 mm, and almost always go to a lake immediately after emergence and reside there for 1 or 2 years. However, there are populations that go to sea (ocean type) or rear in broad, flat rivers (river type). They make very limited use of estuaries and usually spend 2 or 3 years at sea, in offshore waters, and reach a size of about 2-4 kg. Generally spawn in tributaries of lakes but also in outlets and on beaches. May migrate long distances upriver and often enter freshwater months before spawning. Second most abundant species, after pink. Adults at sea do not have spots (but may in freshwater). Freshwater residents, called kokanee, are found in many lakes, often sympatric with sea-run sockeye, and also have been widely introduced.
O. tshawytscha (vernacular on Kamchatka): chinook salmon (king, spring [B.C.], tyee [>30 lbs.], quinnat [New Zealand]). Range in North America from Ventura River of southern California to Point Hope, Alaska. In Asia, from northern Hokkaido to the Anadyr River Eggs (6-7 mm) and fry are among the largest of the salmon (33-37 mm). There are three patterns of freshwater residence: migration to sea immediately after emergence, migration after about 3 months in a river (these two forms are termed "ocean-type"), or migration after a full year or even two in the river (termed "stream-type"). Ocean-type seem to have a more coastal distribution at sea whereas stream-type more often migrate to the open ocean. this seems to co-vary with freshwater life history type. Ocean residence variable, 1-5 years. They typically spawn in large rivers, using deeper water and larger gravel than other salmon species. Largest of the salmon (to 57 kg) but those over 20 kg. are considered large except in particular rivers. Runs are sometimes classified on the basis of adult return timing (i.e., spring, summer and fall) and there is even a run of "winter" chinook in the Sacramento River that returns in winter and spawns in spring. Stream-type juveniles are generally early (spring or summer) returning adults whereas ocean-type are more often fall running adults. Least abundant of the semelparous species. Identified at sea by spots on upper and lower lobes of the tail, on the back, and black gumline inside mouth (hence common name "blackmouth").
O. kisutch (vernacular on Kamchatka): coho salmon (silver, blueback [when small, in B.C.]). Range in North America from Monterey Bay, California to Point Hope, Alaska and in Asia from Hokkaido to the Anadyr River. Eggs are 4.5-6 mm. Fry are smaller than chinook (25-30 mm) but heavier-bodied that the other species, and have colored fins. Typically reside in streams for 1 or 2 years but some go to sea as fry in spring or reside in lakes. Marine distribution is generally coastal; most spend 1 full year (2 summers) at sea but some males return after 1/2 year ("jacks") and some stay out a second year. They generally spawn in small streams in both coastal and interior locations. Adults are generally larger than pink and sockeye but smaller than chum and chinook (range about 0.5 - 10.0 kg). Adults have spots on only the upper lobe of the tail and lack the black mouth of chinook.
O. masou/rhodurus: masu, cherry salmon, yamame (freshwater form); amago. These are considered by some to be distinct species but by others to be sub-species or races. Masu are found in rivers leading into the Sea of Japan and Sea of Okhotsk (Korea, Japan and Russia). There are no native populations outside Asia but transplantation has occurred (e.g., lakes in Ontario). Amago seem to be limited to Japan. Both species are noteworthy for the variations on anadromy. In southern regions, males and females often remain in freshwater until maturity. Farther north, most females go to sea but some males remain in freshwater. In some cases up to 90% of the upstream migrants will be females. They tend to be small (usually 1-2 kg). Amago are said to remain in bays and estuaries rather than going to the open ocean. They also migrate to sea in fall-winter and return about 6 months later in spring. Masu migrations at sea are confined almost exclusively to the seas of Japan and Okhotsk. Age composition varies but most are age 3 or 4. There is some evidence of iteroparity among the yamame.
O. mykiss (formerly Salmo gairdneri) (Dr. Meredith Gairdner, a naturalist employed by the Hudson's Bay Company). A widely distributed, iteroparous species which can be anadromous (termed steelhead) or reside exclusively in freshwater (termed rainbow trout). Its native range is from northwest Mexico (including northern Baja California) to the Kuskokwim River, Alaska (not generally anadromous in Bristol Bay or northern Alaska). It is probably native to the Peace and Athabasca drainages east of the Rockies, and has been successfully introduced almost everywhere (New Zealand, Argentina, China, Nepal, South Africa, eastern North America, etc.). Eggs are small (3-5 mm), deposited in winter-spring on ascending temperature cycles. Fry emerge in spring-summer and reside in streams for their whole lives, or migrate to lakes or the ocean to rear (often after about two years in the stream). Age and size at maturity vary greatly (as young as 1 yr in males and as old as 6 in females). Reported to 26 kg in freshwater (Jewel Lake, B.C.) and over 16 kg for steelhead. Juveniles typically stay in rivers for 2 years before going to sea. Ocean distribution is very broad, especially for those going out the first time. May be divided into ocean maturing and river maturing (a.k.a. winter and summer races) by time of entry into freshwater relative to date of maturation. Percent repeat spawners varies. The Asian form used to be considered a separate species (Salmo mykiss). Adults in seawater have many small spots on the back and tail, and large, square tails.
O. (formerly S.) clarki: cutthroat trout. Occurs as anadromous and freshwater forms along the coast from northern California to southeast Alaska; inland to northern Mexico and central Colorado. The only salmonid native to both sides of the Rocky Mountains; there are races in the Colorado River, Rio Grande and Mississippi-Missouri drainages (Yellowstone Lake), and the headwaters of the Athabasca, Columbia (Arrow Lakes) and Fraser rivers. The anadromous form spawns in winter-spring and young reside in freshwater for about 2 yrs but variations abound. Maximum sizes in freshwater can be very large (19 kg in Pyramid Lake, Nevada). The sea-run form grows to 8 kg and 75 cm in B.C. but most about 1-2 kg. Do not seem to range far out to sea but their marine distribution is poorly-known. Freshwater form may reside in streams or migrate to lakes. Juveniles are very similar to rainbow trout but have somewhat longer lower jaw, larger spots, and red throat marks.
Salvelinus alpinus ("of the mountains"): Arctic char(r). This species has the most northerly distribution of any freshwater fish. It is circumpolar but in our area it is found across the Arctic and in Alaska to the Kenai Peninsula and Kodiak Island. Seems to be more often anadromous north of the Yukon River. They are fall (Sept.-Oct.) spawners and eggs are about 3-4 mm but fecundity is high (3000-5000 or more). Eggs killed by temperatures above 7.8 C. Growth rates are usually very slow and the fish are often old (10-20+ years) and iteroparous. Sea-run fish are about 1-5 kg. Seaward migration is in spring and upriver migration in fall. Some enter lakes to over-winter but do not spawn. Highly variable life history, especially among isolated lake populations. Dwarf freshwater residents and anadromous forms may be sympatric.
S. malma (vernacular name in Kamchatka): Dolly Varden. Distributed from just south of the US - Canada border to Seward Peninsula in Alaska. In Asia, found from Yalu River, Korea to the Anadyr River. Fall spawners, they may over-winter at non-home sites when they are not going to spawn. Inland, high altitude or high latitude populations may be stunted but a Lake Pend Oreille fish was 103 cm and 14.5 kg. Marine migrations are not extensive but are poorly known.
S. confluentus bull trout. Very similar to Dolly Varden in appearance and life history but are distributed more to the south and interior whereas Dolly Varden are more coastal and northerly. Found from McCloud River (northern California), western Montana, Nevada and Idaho, and BC and Alberta.
S. namaycush (Indian name): lake trout. Exclusively freshwater, found in lakes in New England, the Great Lakes region, Montana, Idaho and Alaska, and in all Canadian provinces and territories except Newfoundland. In the southern part of the range the lakes are usually large and deep but they may be in shallower lakes and even rivers in the Yukon and Northwest Territories. They are the least tolerant of salt water of all salmonids but are occasionally found in water to about 12 ppt. They spawn in fall, producing relatively large eggs (5-6 mm). Fecundity may be very high, up to 18,000 eggs per 813 mm female. Spawning occurs in rocky reefs in lakes but rarely in rivers. Reach sexual maturity at age 6-7 or greater and live to be over 20. Record specimen was 46.4 kg from Lake Athabasca, Saskachewan, but others over 35 kg also taken there.
