EXOTICS [Compatibility Mode]

EXOTICS [Compatibility Mode] - Introduced Fishes in Marine...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Introduced Fishes in Marine Systems and Inland Seas A major threat to marine biodiversity Number of marine & estuarine introductions is small compared to freshwater introductions exceeded 120 spp in 1991 and growing many intentional introductions made to enhance fisheries many inadvertent introductions were the result of canal construction or ballast transport Misnomer: Inadvertent Introductions Designation implies accidental or unintentional Really means ‘not turning the mind to a matter’ Inattentive Many ongoing introductions could be avoided if responsible parties did not stick their heads in the sand Introductions are now negligent rather than accidental because we know how and why Ballast-water transport is a 20th century phenomenon Inadvertent introductions via shipping have been occurring for centuries Hull fouling and rock ballast transported many organisms Obscured zoogeography of inverts and probably fishes Affected community structure of many coastal ecosystems Intentional Introductions Generally to enhance fisheries Most did not establish populations did not achieve objectives had deleterious effects In several cases, introduced spp have contributed to the extinction of native fishes, especially endemic species Accurate Information is Fragmentary Many ecosystems have not been thoroughly surveyed many exotics incorrectly identified as “natives” in early surveys many exotics overlooked, especially rare and benign species Introductions to Improve Fisheries Early successes with anadromous spp Former Soviet Union 42 intros of 29 spp 11 (26%) established large populations 5 (12%) established small populations Strong negative effects on native fishes, esp endemics in closed ecosystems Introduced parasites and other inverts altered community structure and reduced fishery landings
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Introductions to Improve Fisheries . .. North America Pacific Coast Transcontinental railroad, 1869, allowed east-west exchange (mostly fw spp) Estuarine and anadromous spp Salmonids, striped bass (Baja to BC), American shad (Baja to USSR) Introductions to Improve Fisheries . .. North America (cont)
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 09/13/2010 for the course OCS 4012 taught by Professor Baltz,d during the Spring '08 term at LSU.

Page1 / 5

EXOTICS [Compatibility Mode] - Introduced Fishes in Marine...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online