Tag Archives: Trout

McMaster University Fish Scientists Weighed Hamilton

McMaster University Biology Dept. at Hamilton, Ontario

Tuesday November 9 2010

Water Toxicity

Bob's Pike



Dr. Chris Wood is an expert in Fish Physiology. At McMaster the wood Lab is The Physiology of Transport Processes and Metabolism, and the Aquatic Toxicology of Fish and Crustaceans. Here Dr. Wood inspires students with his love of research and his lifetime work has been encouraging and training the next generation of scientists. On April 17th, Dr. Chris Wood and Dr. Adolto Bimchini were recipients of one of eight International Canada Research Chairs recently awarded by the International Development Research Centre and the Canada Research Chair program. Dr. Chris Wood has the “Canada Research Chair in Environment and Health.” They have been awarded $1,000,000.00 to conduct environmental research in Brazil and Canada. Their research program is entitled “Battling pollution in coastal areas.” They were selected from 104 applicants. From what they learn in Brazil in the next five years ( 2,010 – 2.015), they will determine what is applicable to Hamilton Harbour cleanup. Dr. Wood in 2,007 was honored by the Royal Society of Canada, and awarded the Miroslaw Remonowski Medal for his work on metal toxicity in acquatic ecosystems.

Dr. Chris Wood as a PhD candidate himself – (1) Conducted a series of NSERC supported research projects on acid-base regulation, lactate and ammonia transport, and gas exchange in Rainbow Trout. (2) He developed an unique isolated tail-trunk preparation to serve as an in situ physiological moded to investigate metabolic, acid-base and ion regulation in Trout Muscel. The ion is an atom or group of atoms that has acquired a net electic charge by gaining or losing one or more electrons. (3) He played a major role in developing and improving a series of muscel sampling, processing and enzymatic analysis for Fish Muscel. (4) He supported a project on bioavaliability and toxicity of heavy metals in freshwater ecosystems.

His 2,008 study with Bucking on Rainbow Trout showed the net base excretion to the water increased greatly at the same time as a compensaion of a postprandial alkaline tide in the bloodstream. In another study, he indicates the results point out the need to incorporate sulfide into the acute biotic liqand models and to assess its potentially large role in preventing chronic toxicity. Another study ponts to the importance of salt and water absorbtion from the food by the gastrointestinal tract and its impact on ion-osoregulation have been overlooked by fish physiologists. In freshwater fish the quantities of most major electrolytes ingested via a normal ration far exceed those transported from the water by gills, but net absorbtion rates of specific ions vary greatly with a range of influences, including complex intractions involving musins and bile salts. In freshwater the gills and kidnesy are the major organs involved in salt uptake and water loss, respectively. In nature, most fish feed either opportunistically or on a diuranal cycle. And, we know that gut blood flow is elevated following feeding. What Dr. Wood intends to show in this study is when freshwater fish are allowed to feed, the role of gastrointestinal tract in salt and water balance is far more important than previously believed.

Water Quality

In the Saturday, Nov. 6, 2,010 Hamilton Spectator their article is aptly titled ” On the scale of fish scientists, he’s tops.” He uses water chemistry to predict whether or not the metal is going to be toxic to fish. He also pointed out that in Lake Ontario, which is quite rich in clacium, bicarbonate and dissolved organic carbon, there are many substances that will bind up the free ion and prevent it fron going on the fish gills. That means that a level of metal which wold be very benign and not have any effect in Lake Ontario would be very dangerous in a Muskoka Lake, according to the Spectator. In a study of Dr. Woods from Kenya, Africa he found a unique fish where the pH is 10 , that would kill most fish. But this fish, similar to humans excretes urea. This might become useful, said Dr. Woods, because if you take that genetic pathway and put it into aquaculture fish and get the fish to excrete urea instead of ammonia, you would need to have less water flow and less heating of the water , and you could save money.

Our waterways

sources: Web and The Hamilton Spectator

Photography

Doug Worrall

Lake Ontario’s Recreational Fishery Hamilton

Lake Ontario’s Recreational Fishery Hamilton

Monday September 27th 2010

Viewing the bay
Until 1933, the U.S. state agencies tried to establish reproducing populations of Chinook salmon in the Great Lakes , but were unsuccessful. Since 1967, Chinook salmon have been stocked to support the foundation of Lake Ontario’s  “Recreational Fishery”  for three types of anglers: (1) small boat anglers; (2) shoreline anglers; and, (3) break-wall anglers.  Studies in the Lake Michigan tributaries have estimated that natural reproduction by Chinook salmon has contributed to an extimated 23% of the total Chinook salmon population , in 1982. The Province of Canada Fishing Law of 1858 was modified with the Act for the regulation of Fishing and Protection of Fisheries in 1868.  .Margaret Beattie  Boque in  Fishing the Great Lakes, An Environmental History 1783 – 1933,  says, “The Act of 1868 put safeguards to the Salmon in Lake Ontario, already in critical condition, specifying a closed season, mesh sizes of nets, and distance between nets.  This Act protected entrances to spawning streams, spawning grounds, and prohibited taking of roe, salmon fry, parrs and smolts, and fish less than three pounds in weight. The study of fish production ,food habits, and activities of fish fauna is Limnology.  The study of Morphology investigates things like temperature.  Fisheries and Oceans Canada (DFO) key priorities for Fishery Management in Canada include (1) environmental sustainability; (2) economic viability, and  (3) the inclusion of stakeholders in the decision – making process.  In this aquaculture, the research tool to attaining  strong conservation outcomes is risk management because it supports long-term sustainability.  The fishery decision-making framework incorporates the popular tool for fisheries management and conservation of the precautionary approach (PA), or, aquatic precautionary approach (APA).
The combination of angler preference for large, fast-growing salmon, the desire of fishing managers for a predator what would control large number of alewives, and the comparable lower hatchery production costs of Chinook salmon led to them becoming the key player in the species mix of Lake Ontario’s salmon community.  Recently concern is for long-term stability of the predator/prey system.  Therefore stocking levels were very controversial and came under public scruiting.  That is: (1) 1984 – peaked 4.2 million; (2) 1985 – 1992, 3.2 to 3.6 million; (3) stocking reduced substantially based on a 1992 management reveiw; (4) 1994-1996, 1.7 million annually; (6) 1997, 2.0 to 2.2 million annually; and, (7) 1999, stakeholders demand for  a second management review and stocking was only slightly increased; (8) in 2,0o9, 2.3 million were stocked. And, from 1982 – 1999 Chinook salmon represented 32% to 54% of annual stocking levels. In “transactions of the American Fisheries Society in a 2,009 study they state: “Lake Ontario’s large and complex system and our ability to control the outcome through stocking may be less than people think. Lake Ontario fish managers are not convinced a new stocking plan is needed.  It is something biologists and managers have to keep an eye on.”

Jerry's catch

Salmon are heading to Hamilton Harbour once the temperature is cooler in the evening and rain comes to raise the low water levels in the rivers for the salmon to migrate upstream to spawn.  The salmon usually run two days after a heavy rain. The salmon are “stacked” and have not been able to migrate due to low water conditions. In Toronto, the Humber River Dam stairs make it easier for salmon to reach their goal, without making it easier than nature intended.   The MNR and partners stock 1.7 million salmon and trout into Lake Ontario annually to (a) provide fising and support native species restoration.  On these, 85,000 Chinook salmon are stocked in the Credit River.  The Port Credit Salmon and Trout Association  (PCSTA)  crucial role is caring for the fish.  Plus, the CRAA – Credit River  Anglers  Association watershed ground enhances native species and is involved in stocking.  The Credit River begins in Orangeville at the Island Lake Reservoir. If you fish west of the Credit Forks a fishing expert advise is  ” you need to be one part angler and two parts billy-goat.”  The Upper Credit River includes Belfountain Conservation Area.. The Steetsville Dam, and Roger’s Creek are part of the Credit watershed.    The Lower Credit river ends by spilling into Lake Ontario at the Credit River Mouth, known as Port Credit which prides itself as the “Salmon Capital of Ontario“, located in the city of Mississauga, Ontario  One of the best angler spots for the salmon run on the Credit River is at Erindale Park at Dundas and Mississauga Roads.  Bronte Creek is in Oakville, and one of the best spots to catch salmon is where the river runs under Hwy. #5 or Dundas Street and near Appleby Line in Burlington.; and  at Shell Park in Oakville. There is also the Ganaraska (Ganny) River in Port Hope.  There are other rivers, buth they do not get the salmon run as these ones.   In Lake Ontario Outdoors a Fishing Captain advises: ” Knowing water movement and temperature patters is the key to consistent action. Watching and learning weather and wind patterns and their effect can greatly increase the  success rate of the average angler.  One angler already made his catch this week in Hamilton Harbour with minnows. The sluggish egg laying (adult) salmon are too tired to eat so they rarely get caught.   On Thursday, while photographing a red-tailed hawk that dove for a mouse on the railroad tracks, Doug saw a Salmon or Trout jump 3 times like a dolphin coming towards him.   Doug talked to some of the fishermen and this is what they are using: (1) Boat Fishermen are using”down-riggers”:, 6 poles at once depending on people on the boat, they fish  to 60 feet  in lake depth, and some boats troll above the surface with “Lures.”  (2) Shore-water (shorline) Fisherman are using ROE bags, and Pink Marshmallows. (3) Breakwater Fishermen are using Spoon Lures to entice the young salmon.

Chinook Salmon is the largest  Pacific  Salmon in 1,000 rivers and streams of North America.  It’s normal life cycle includes their  being anadromous (migrate into streams to spawn), and, semelparous (producing all offspring  at once and die after spawning).  Lake Ontario Chinook spawn  change form in Autumn (fall) . The growth rate of the species is rapid.  In the Fall spawing salmon deposit eggs in grave nests and die ( well, kind of decay). the Fry hatch in the Spring and grown int the stream. These fry spend a year or more or more in freshwater.   Then the fingerlings migrate downstream.The spawning age varies from 2 to 7 years, but most typically four years.  Chinook smolts spend as little as a few weeks in freshwater to as long as one year.     Individuals usually reach sexual maturity within the first three to five years growing to Smolt and entre the ocean (or in Ontario the oceanic Lake). The Chinook  follow their inner homing device and  enter the rivers and head for spawning areas in the Autumn (Fall) and the life cycle  is repeated.  The Fall Run is robust and deep bodied Chinook who spawn soon afer arriving in the spawning grounds usually in large rivers.   It is the Fall run, that anglers await to catch Chinook salmon and the Lake Ontario record is 28.6 pounds.   But, the Spring Chinook are smaller and slimmer and has a characteristic odor.

Coho Salmon is a major Pacific salmon sportsfish  are stocked in Lake Ontario, and, historically, in  1933  they were introduced when the Ohio Division of Conservation released them into Lake Erie. It was in 1966 that  Michigan and Ohio stocked Coho Salmon which established naturally reproducing populations.  Currently, these low level of natural reproduction is supplemented by stocking to enhance the recreational fishery.  Unlike Chinook Salmon, the Coho habitat spend half of their life cycle rearing and feeding ins streams and small freshwater tributaries.  The Adults migrate from a marine environment into freshwater stream and rivers of their birth in order to mate (anadromyl).   Their spawning habitat are small streams with stable gravel substrates.  The remainder of the life cycle is spend foraging in estuarine and marine waters of the ocean (Great Lakes in Ontario). The three year olds return to streams of origin to spawn and die.  Two year old are called “jacks.”   “Jack” salmon can be half the size of an adult salmon.   In the Spawing phase,the jaw and teeth of the Coho become hooked and they develop bright red sides and bluesh-green heads and backs. The females may be darker red than the males, but both showing a pronounced hook on the nose (snout).   The males show a slightly arching of  the back. Females prepare several Redd’s (nests) where the eggs will remain for six to seven weeks until they hatch ( 90 to 150 days after deposition, depending on water temperature).  The female will guard the Redd’s for 4 to 25 days before dying.    As time of migration to sea approaches the juvenile coho lose their parr marks – a pattern of vertical bars and spots useful for camouflage, and gain the dark back and light belly coloration used by fish living in open waters.  Their gills and kidnesy also begin to change so that they can process salt water ( but in Ontario they are in freshwater).  In the freshwater stages, they feed on plankton and insects, then switch to a diet of small fishes as adults  Large Coho and Chinook salmon prey almost exclusively on alewife and rainbow smelt in Lake Ontario.

RBG Fishway

The next two days lots of rain and colder weather will entice all the stacked-up fish to start the run to spawn into Hamilton Harbour. My Prediction, by Wednesday you will be able to start catching Brown trout, Lake trout, Salmon and more.

Hope to see you there.

By J Darby

Photography

Doug Worrall