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Trout

Trout. Evolution. The evolution of trout can be traced back at least 100 million years ago to a fish found in the Salmonidae family. The scientific name of this fish was Eosalmo driftwoodensis. Classification of Trout. Kingdom : Animalia Phylum: Chordata Class: Actinopterygii

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Trout

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  1. Trout

  2. Evolution • The evolution of trout can be traced back at least 100 million years ago to a fish found in the Salmonidae family. • The scientific name of this fish was Eosalmo driftwoodensis.

  3. Classification of Trout • Kingdom : Animalia • Phylum: Chordata • Class: Actinopterygii • Order: Salmoniformes • Family: Salmonidae • Genus: various • Species: various

  4. Classification of Trout • Kingdom : Animalia • Organisms in this Kingdom are those who are multicellular (eukaryotic cells) are mobile and do not make their own food.

  5. Classification of Trout • Phylum: Chordata • These organisms have a backbone. • They are known as “vertebrates”.

  6. Classification of Trout • Class: Actinopterygii • These organisms are fishes which have rayed fins. • This means that there are bony ‘rays’ found within their fins.

  7. Classification of Trout • Order: Salmoniformes • These are fish who have pelvic fins near the back of the fish. • They also have an adipose fin located near the back of the fish.

  8. Family / Genus / Species • All trout and their relatives fall into the classification Family Salmonidae. • All trout fall into one of three genera: Salvelinus , Salmo , orOncorhynchus. • The genus is determined by how closely the fish is related to others along the evolutionary tree. • Within each genera there are species. • Each species is determined by the ability to successfully reproduce. • Some members of a species have interbreed and created variations which look very different. However, the ability to successfully reproduce puts them into the same species. These variations are called subspecies.

  9. Salmonidae Family -- Salmo Salvelinus Onchorynchus Genus -- -Atlantic Salmon (salar) -Brown (trutta) -Arctic Char (alpinus) -Brook (fontinalis) -Lake (namaycush) -Dolly Varden (malma) -Bull Trout (confluentus) Species • -Rainbow (mykiss) • -Pacific Salmon (5 types) • -Cut throat (4 types) • -Apache (apache) • Gila (gilae) • -Golden (2 types)

  10. Genus - Salmo • It is unclear which of the two species evolved from the other but, they are the only two species from this genus that are found in North America. • The Salmo genus contains only 2 of the 10 trout species. • Atlantic Salmon (salar) • Brown Trout (trutta)

  11. Atlantic Salmon (salar) • Atlantic Salmon are found on the North American and European continents. • Once they reach maturity, Atlantic Salmon return to their ‘home’ stream to spawn but often return to the sea and repeat the process each year. • Atlantic Salmon are naturally anadromous but a few subspecies (Ouananiche, Sebagos) have made adaptations to live their entire lives in fresh water.

  12. Brown Trout (trutta) • The Brown Trout is not native to North America. It was brought over from Europe in 1883. Since then, the species has thrived in North American waters and have become commonplace. • The Brown Trout is the only trout with red on its adipose fin. This coloring is not found on hatchery fish.

  13. Genus - Oncorhynchus • Each member of this genus evolved from the Pacific Salmon. • They were not considered a separate genus until 1988 but are now listed separately because of their common ancestor • The Oncorhynchus genus has 7 of the 10 species of trout. • Rainbow Trout (mykiss) • Pacific Salmon (5 types) • Cutthroat Trout (clarki)

  14. Rainbow Trout (mykiss) • Rainbow Trout originated in the western part of North America. • All western trout are closely related to the rainbow trout. There are several variations or subspecies or Rainbow Trout which include: California & Mexican Golden, Apache, and Gila Trout. • Rainbow Trout Prefer fast moving water and can be found in riffles rather than pools. • Rainbow Trout that have become anadromous are known as Steelhead Trout which tend to be much larger than landlocked species.

  15. Pacific Salmon • There are 5 different species of Pacific Salmon (Chinook, Coho, Sockeye, Chum, Pink), each being anadromous. • Each of the 5 species returns to their ‘home stream’ to spawn. • Unlike the Atlantic Salmon, the Pacific Salmon dies after spawning.

  16. Cutthroat Trout (clarki) • There are four recognized subspecies of Cutthroat Trout. These subspecies are determined by their native ranges which have produced slight color variations. • Their place of origin is Western North America. • Inland Cutthroats tend to have fewer spots than those found nearer the coast. • They get their name from the brilliant red found along the underside of their mouth and head.

  17. Genus - Salvelinus • This species in this genus split long ago. The landlocked versions of this genus evolved into the Brooke & Lake Trout, while the oceanic versions evolved into the Arctic & Dolly Varden Char. • This genus includes 5 of the known 10 species of trout. • Arctic Char (alpinus) • Brook Trout (fontinalis) • Lake Trout (namaycush) • Dolly Varden Char (malma) • Bull Trout (confluentus)

  18. Arctic Char (alpinus) - Arctic Char is perhaps the most colorful of the trout. - Some Arctic char are andromous (live part of their lives in fresh water and part in the ocean) while some spend their entire lives in fresh water. - Landlocked Arctic Char found in the northeast parts of North America are often called by different names such as: blueback, Sunapee, Marsten’s or Red Trout.

  19. Dolly Varden Char (malma) • Dolly Varden Char are found along rivers and streams on the west coast of North America. • These char are seldom found inland but more commonly found near coastal waters. • At one time, Bull Trout were thought to be a subspecies of Dolly Varden Char but after further study it was determined that the two were separate species.

  20. Bull Trout (confluentus) • Bull Trout are native to the coastal waters of Oregon, Washington, and British Columbia. • Bull Trout fill a similar niche as its cousin the Brook Trout and only reaches a length of about 8 inches at maturity.

  21. Lake Trout (namaycush) • Lake Trout inhabit the deep waters of cold naturally occuring lakes. They are native only to North America. • The tail of the Lake Trout is deeply forked. • Lake Trout require cold and heavily oxygenated water. • Lake Trout mature slowly and do not produce many eggs.

  22. Splake • A splake is a cross bread of two different species. • When a female lake trout and a male brook trout cross bread a splake is formed. • This crossbreeding is very rare and only occurs in a few lakes found in Canada.

  23. Brook Trout (fontinalis) • The Brook Trout is the state fish of Pennsylvania. It is closely related to Lake Trout and can sometimes crossbreed to form a splake. • Brook Trout are native to the east coast of North America and prefer small cold water streams. • They are very sensitive to water temperature and quality which has led to habitat loss. Brook Trout prefer water temperatures between 55 and 65 degrees F but can survive in water as low as 32 degrees F. Brook Trout can also tolerate high levels of water acidity.

  24. What is a Brook Trout? • A Salmonid • Related to brown, rainbow and other trout and salmon • Salvelinusfontinalis – actually char Closely related to: • Lake trout • Arctic char • Bull trout

  25. What is a Brook Trout? Unique external features • Light spots on dark background • Tiny scales • White piping on lower fins adjacent to narrow black striping • Wormlike markings on back and head

  26. Native Trout Evolved over many thousands of years where it is still living and reproducing. Native and Wild = Brookies are Pennsylvania’s only native stream-dwelling salmonid and our state fish.

  27. Why are Brook Trout Important? • Indicators of clean water and healthy aquatic systems • Affords higher level of water quality protection • Important part of the food web • Provides economic benefits • State Fish of Pennsylvania • And Michigan, New Hampshire, New Jersey, New York, Vermont, Virginia, West Virginia and Georgia. • Considered by many to be one of the most beautiful freshwater fish and great fun to fish for

  28. Brook Trout History and Heritage • In eastern N. America prior to any human habitation • Described in Native American legends • Widespread in PA when the first Europeans arrived and represented first trout angling experiences • Thrived in immense numbers and reached sizes we can only imagine

  29. The DeclineWhat Happened?

  30. Logging • Audubon commented about the destruction of the forest when he was traveling in the Pocono Mountain Region in 1829. • By the early 1900’s, loggers had denuded the massive hemlock and pine forests, followed by extensive fires.

  31. Logging

  32. The Decline - Logging • This lead to severe erosion and sedimentation, elevated water temperatures and predator vulnerability. • Brookies retreated upstream to escape and began to vanish from downstream reaches.

  33. Coal • In the early 1900s, major coal mining began • Many miles of brook trout waters were devastated by acid mine drainage

  34. Acid Deposition • Our headwater streams, the last brookie refuges, are now being assaulted by acid deposition • acid rain • snow • Particulates • Results from combustion of fossil fuels

  35. Other Poor Land Uses and Exotics • Poor agricultural practices • Nutrients • Sediment • Urbanization • Stormwater • Sewage • Roads • Exotic species • Wooly adelgid, gypsy moth, etc

  36. Introduction of the Brown Trout • Introduced into PA streams in the 1880’s • Quickly took over in larger freestone and limestone waters • Brook trout were able to hold on in headwater streams where they are mostly found today

  37. Stocking

  38. Stocking • Many streams with native trout populations are being stocked • Stocking attracts large numbers of anglers, encouraging over-harvest • Most of the legal-sized trout (native and stocked) are quickly removed • Hatchery trout compete with native trout for living space and food • Hatchery trout have the potential to introduce disease and parasites which spread among native trout

  39. Stocking Legal Size Brook Trout per Mile Before and After the Cessation of Stocking in Nine Predominately Brook Trout Streams Source: PFBC data, Trout Summit, 2002

  40. The Decline - Summary • Logging • Coal • Acid Deposition • Land Use • Brown Trout • Stocking

  41. What’s it like today? • Now, few brook trout exceed 8” • A 10” brookie is exceptional • Remote freestone streams still hold plenty of 8”- 10” brookies • A few limestone streams yield large brookies

  42. 16-Inch Wild Brookie from A Limestone Stream In Eastern PA Photo courtesy of Chaz Macdonald

  43. Current Status of Brook Trout in PA • Historic range • 1% still intact (>90% occupied) • 9% reduced (50-90% occupied) • 39% greatly reduced (<50% occupied) • 34% extirpated • 17% no data

  44. Brook Trout RequirementsWhat Do Brook Trout Need to Survive and Prosper?

  45. Streams must contain enough water year round to support trout and trout food Causes of critically low flows: Drought Water withdrawals Irrigation Bottled water Domestic water supplies Gas Extraction (Fracking) Impoundments Collect water and reduce or eliminate downstream flows Water Quantity

  46. Cold Water • Trout need cold water • Brook trout prefer colder water than brown or rainbow trout • Cold water holds more 02 than warmer water • If water warms and holds less 02, brookies get stressed • They have to move to find cooler, more 02 rich water or suffocate

  47. Cold Water • Coldwater stream reaches have declined • Causes of Critical Warming: • Reductions or loss of forested riparian corridors • Impoundments • Surface Runoff • Global Warming

  48. Water Quality pH • Tolerance Ranges • Brook trout reproduction fails below pH of about 5 • Causes of critically low pH (or high acidity) • Acid Deposition and poor soil buffering • Acid Mine Drainage

  49. Water Quality Suspended Solids Excess suspended solids from poor land use practices negatively affect trout survival • Impair trout reproduction • Reduce benthic invertebrate habitat • Deposit sediment in critical pools

  50. Habitat • In PA, good habitat is promoted by • Natural stream flow with a natural meander pattern and riffle-pool ratio • Forested, undisturbed riparian corridors • Good habitat is reducedby: • Stream channelization • Removal of riparian vegetation • Removal of woody debris • Stream encroachment

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