Fishes of the Rogue River. Steven Mazur Assistant District Fish Biologist

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1 Fishes of the Rogue River Steven Mazur Assistant District Fish Biologist

2 Outline Basic life histories of Rogue River fish Salmon Human interaction

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6 Pacific Lamprey (Lampetra tridentata) -Pacific lampreys belong to a primitive group of fishes that are eel-like in form but lack the jaws and paired fins of true fishes -Pacific lampreys in their adult form have round sucker-like mouth, no scales, and gill openings -Lampreys in general are identified mainly by the number, position, and structure of their teeth -Pacific lampreys have 3 large anterior teeth and many smaller posterior teeth -Can reach lengths up to 30 inches as adults -Pacific lamprey have a very unique anadromous life cycle -Lampreys have a fossil record that is 500 million years old!

7 Adults live in the ocean 1-3 years and feed parasitically on host fish Pacific Lamprey Life Cycle Adults migrate to freshwater between Feb and June and live there for about a year before spawning They lose around 20% of their body weight during this time. Macropthalmia emigrate to the ocean from Nov to March - - Adults spawn between March and July in gravel nests, then die. - Ammocoetes transform to juveniles (macropthalmia) and develop eyes and teeth Eggs hatch into larvae (ammocoetes) Ammocoetes live in silt/sand substrates and filter feed for 3-7 years on diatoms and phytoplankton

8 Threespine Stickleback (Gasterosteus aculeatus) - Found in both freshwater and saltwater - 4 cm to 6 cm in length, can reach sizes up to 10 cm in marine environments - Freshwater habitat is typically well-vegetated areas that usually have muddy or sandy bottoms - Marine habitat is coastal areas; drifting patches of seaweed, estuaries - Feed off of zooplankton, small crustaceans, aquatic insects, and worms - Life expectancy is 1 to 3 years - Spawning occurs in the early spring and summer - Males change body and eye color, then court females by performing a zig-zag dance ritual, they also build the nest and take care of the eggs with no help from the female - Males will fan the eggs with their tail for 7-10 days after fertilization to help oxygenate them

9 Klamath smallscale sucker (Catostomus rimiculus) - Adults average 35 cm 50 cm in length - Sub-terminal sucker mouth - Schooling fish that prefers slower, deep water - Spawning occurs in the spring, adults move into the tributaries - Emit chemicals to alert other fish when in danger, have excellent hearing - Dwarfism (small size at sexual maturity) shown in isolated populations - Mature at only 2 years old ^11 cm at Jenny Creek, Oregon - Mature at 5 years old ^20 cm on the Rogue River - Can live up to 15 years

10 Coast Range Sculpin (Cottus aleuticus) Prickly Sculpin (Cottus asper) Reticulate Sculpin (Cottus perplexus) Reticulate Sculpin Coast Range Sculpin - Are all nocturnal - Prefer to live in fast moving water riffles/deep pools - Live in fresh and brackish water - Spend first month of their lives as surface feeders in a unique larval stage - Use pectoral fins as hydrofoils to stay on the bottom, also no swim bladder - Males dig the nest and guard the eggs, multiple females lay eggs in one nest - Can live up to 7 years, but rarely reach over 15 cm - Spawn February to mid June - Slightly different niches; Coast Range = shallow riffles, Prickly = deep pools, Reticulate = warmer rivers, swamp-like conditions Prickly Sculpin

11 Speckled Dace (Rhinichthys osculus) - Live in a vast array of habitats - Generally found in 2 nd and 3 rd order streams - Important forage fish that is typically 8 11 cm in length - Can live in water with a dissolved oxygen of 1 mg/l and a temperature up to 88 F - Spawns in June and July - Eggs hatch in only 6 days - Can live up to 6 years

12 White Sturgeon (Acipenser transmontanus) -Largest sturgeon in North America -Anadromous life history (born in freshwater, live in salt water, spawn in freshwater) -Unique vacuum like mouth and barbell whiskers to feed on bottom -Scutes instead of scales, large bony armor-like plates (36 or more on w. sturgeon) -Spawn in deep swift-water riffles from February to early June -Females only spawn once every 5-11 years -Females sexually mature at 18 years, males at 14 years

13 River Monsters! - Been on fossil record for 200 million years - Can reach 20+ feet and weigh over 1500 lbs! - Skeletons are mostly cartilage - Can live to be over 150 years old - True living fossil

14 Green Sturgeon (Acipenser medirostris) - Slightly smaller than the white sturgeon - Can reach 7 ft. 350 lbs. and live up to 60 years - Most widely distributed and most marine of all sturgeon species - Green sturgeon fertilization and hatching rates are 41% and 28% - White sturgeon fertilization and hatching rates are 95% and 82% - Green sturgeon larvae survival is very high 93%. Greens have larger larvae and are twice the size of w. sturgeon in their first five days. - Hatchling green sturgeon embryos seek cover, w. sturgeon embryos drift downstream

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16 Coastal Cutthroat Trout (Oncorhynchus clarkii) - Found in streams and rivers from Northern California to Prince William Sound, Alaska - Has the most flexible and diverse life history of any Oregon salmonids - Cutthroats classified into four categories; resident, fluvial, adfluvial, anadromous - Range in size from 6 inches in resident cutthroat, to 20+ inches in sea-run cutthroat - In marine environments can grow an inch a month - Sea-run cutthroat spawn late winter to spring, then return to sea - Resident, fluvial, adfluvial cutthroat spawn in late summer to fall - Least aggressive of all salmon and trout, often pushed to marginal habitat - Canary in the coal mine cutthroats require healthy watersheds

17 Steelhead (Oncorynchus mykiss) - Rogue River has summer steelhead, winter steelhead, and a unique half-pounder run - Steelhead can return to sea after spawning - Females dig redds into gravel to deposit their eggs - Summer steelhead enter the Rogue in May average length in inches, 3 lbs - Winter steelhead enter the Rogue in November bigger than summer steelhead due to only 50% having half-pounder history

18 Half-Pounders - Half-Pounder life history is unique to only four rivers in the world; Rogue, Eel, Klamath, Mad - 1 to 3 year old steelhead smolts journey to the ocean between March and May, then return to freshwater 2-4 months later, as sexually immature sub-adults - Half-pounder steelhead then overwinter in the river, before returning to the ocean in the spring - No convincing theories to explain half-pounder life history have been developed

19 Coho (Oncorhynchus kisutch) - Also known as Silver Salmon - Coho smolts migrate to the ocean in the spring of their second year, spend months at sea, then return to freshwater in the fall as 3 year old adults - Average adult size is 24 inches, 8 lbs. - Listed as sensitive vulnerable on the Oregon coast Key concerns for the upper Rogue population; loss of over-winter tributary habitat complexity, floodplain connectivity, over-summer water temperatures and habitat access. ODFW Small, relatively low-gradient tributary streams for rearing - Prefer instream large and small woody debris - Pea to orange-size spawning gravel - Tree lined, shaded banks - Clean flowing water

20 Chinook (Oncorhynchus tshawytscha) - King salmon are the largest of the salmonids - Chinook can spend up to 8 years in the ocean before returning to freshwater to spawn - Spawn in rivers that are larger and deeper than other salmon would utilize - Can reach sizes up to lbs! - Rogue river has spring chinook and fall chinook runs - Spring chinook start to show up in May, fall chinook in August - Spring chinook can be in freshwater for up to 8 months before spawning - Fall chinook are usually in freshwater around 1 month before spawning

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23 can get HUGE!!!

24 Salmonid Anadromous Life Cycle Eggs Eggs Adults return to freshwater to spawn Alevin Fry Adult ocean phase Parr Smolt

25 Juvenile Salmonids

26 Alevin & Fry Approximately 1 in length Recently hatched salmonids that survive by absorbing their yolk sac Still living within the gravel Redd Yolk sac fully absorbed. Now free swimming Start moving toward saltwater

27 Smoltification Process How does an anadromous life cycle increase reproductive success (fitness)? Rivers - relatively few predators, relatively low productivity Ocean/Estuary - many predators, high productivity *Behavioral changes territorial and bottom dwelling, to schooling and pelagic *Physical alterations Na + Cl - ATPase protein increases 2 to 5 fold, osmoregulation, oxygen transport, growth, color, shape, negative rheotaxis

28 Fresh Water Life Salt Water Life vs. ~0% Salinity 35% Salinity Water gain by osmosis Salmon Body Fluids = 18% Salinity Water loss by osmosis Water gain is countered by frequent urination, salt is absorbed by gills. Does not drink fresh water. Water loss countered by excreting salt through gills, constantly drinking seawater. Produces very small amounts of very salty urine.

29 As smolts & juveniles they eat primarily insect larvae, small insects and plankton. The diet of a salmonid As adutls they feed on pelagic amphipods, krill, squid and small fish-such as smelt.

30 How we age salmonids Rings on scales are counted similar to tree rings Scales are collected from an area just above the Lateral Line and behind the Dorsal Fin Rings are called circuli Summer rings are normally widely spaced Winter rings are narrowly spaced & are called annuli

31 Human Interaction On the Rogue River

32 Riparian Management Helps prevent erosion Provide shade for cooler water Provide critical food & shelter Riparian setback ordinance State & Local regulations

33 Established 1877 by Robert Deniston Hume 1893 Destroyed by fire 1906 Rebuilt 1908 Hume s propagation methods adopted by US Bureau of Fisheries 1910 Ownership changes to Macleay Estate 1926 Oregon Fish Commission takes over Knox Family purchases Indian Creek Ranch and surrounding land s ODFW STEP program involved Currently run by volunteers of the Curry Anadromous Fishermen

34 Sea Lion Hazing 2005 estimates of 50-75% of hooked fish were taken by Sea Lions 2006 program started in Gold Beach After first year estimates of hooked fish taken is down to 5% Barriers on docks, hazing with non-lethal noise makers, removal of easy food source at cleaning station

35 Fishing & Recreation World famous sport Chinook & Steelhead Fishery 1895 Jet boats start delivering mail on Rogue River. 84 miles of National Wild & Scenic designation starting 11 miles east of Gold Beach

36 Port Dredging & Gravel Mining Channel authorized by Rivers & Harbor Act of 1954 Jetty completion & main channel dredging started in 1960 & is maintained annually Entrance to basin is 10 feet deep & 150 feet wide Main channel is 13 feet deep & 300 feet wide Basin access channel dredged until South Jetty extended & Port breakwater constructed Port realigned the basin access & dredging has not been needed since 1984 Three timber pile groins built along south jetty

37 Non Point Source Sediment Input Juvenile steelhead over 100%, 80%, and 0% embedded substrates (left to right). Decreases dissolved oxygen in the water Decreases water exchange thru the Redd Buries the Redd, entrapping the fry beneath the sediment Causes declines in growth rate Lower prey availability Some causes of: Roads Livestock Landslides Vegetation removal Increases aggression & activity (due to increased competition from decreased prey)

38 Pond on Elephant Bar trail, flowing to river

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46 Questions?