The official web resource of the
Colorado Aquaculture Association
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Have you ever been told “Get used to it… life isn’t fair”? I’m willing to bet that nearly all of us have heard those words at one time or another. Never-the-less, when it comes to treatment of fish farmers and anglers I’m just not willing to say, “Well, I guess that’s the way it is.” Okay, so maybe I’m biased and maybe I’m about to provide a bit of a rant, but as a certified geezer maybe I’m entitled to rant once in awhile. The apparent disparity between terrestrial and aquatic management standards, and the regulations based on those standards, has been “sticking in my craw” for a long time, so bear with me as I vent. I’ll try to avoid straying too far from my scientific roots. Management practices, and the regulations implementing those management concepts, should be fair and they need to be scientifically valid. My complaint is the fact that standards for aquatic ecosystem management are frequently more rigorous than those applied to similar management issues for terrestrial ecosystems. In some cases, they are just plain impossible to achieve. Adding to my irritation is the fact that the rationale for these differences frequently is not based on scientifically valid facts. They often appear to be based on “conventional wisdom.” Conventional wisdom, especially “conventional green wisdom” is likely to be based on beliefs, not valid science… always remember…beliefs can explain everything… beliefs can also justify anything… but do they bring understanding of nature? Usually they do not. Are there scientifically valid reasons for treating aquatic systems differently than terrestrial systems? Yes, but the management goals must be reasonable and achievable, not some pie-in-the-sky dream based on turning back the calendar a few hundred years. In a modern world with high human populations, it is not reasonable to think that we can return to an imaginary pristine condition that someone believes existed in the past. It is not reasonable, nor feasible to require aquatic ecosystems to be more pristine than terrestrial counterparts. I don’t think that resource agencies and environmental interest groups specifically target fish farmers, anglers, and other users of aquatic systems for extra-stringent regulations. Rather, it’s a matter of not recognizing the changes that have already happened and believing that pristine aquatic conditions can be restored even though the land around those waters is anything but pristine. Basic characteristics of aquatic ecosystems do make a difference with respect to aquatic resource management. Water flows toward the oceans, while soil and rocks basically stay in place. Fish and aquatic animals move with the waters and generally stay out of sight. In contrast, birds, most mammals, and other terrestrial animals are readily observed and move at their own volition. Macroscopic terrestrial plants are rooted in place. What goes on in aquatic systems is hidden from view, but activities in terrestrial systems can be watched, often to the delight of the observer. Humans are much more a part of terrestrial systems than they are of aquatic systems. When changes occur, good or bad, the terrestrial changes are obvious, but changes in aquatic systems are out of sight… and generally out of mind… except for the most onerous situations, or by the efforts of the most determined observers. When forests or prairies are converted to farm land or housing developments, it’s quite clear that the ecosystems have been changed permanently. Changes to aquatic systems don’t seem so obvious, even in the case of dams and reservoirs. To a casual observer, the waters of the creek, river, or lake look pretty much the same as they did 500 years ago. However, such differences do not provide a scientifically valid basis for concluding that aquatic systems are more pristine and therefore need to be managed and regulated more stringently. Perhaps by now readers are asking whether or not I can provide examples of management or regulatory differences that support my arguments. Consider the difference between wolf restoration programs and paddlefish restoration efforts. Wolves were brought to Yellowstone National Park from Canadian populations more than 1000 miles away. Paddlefish from Missouri were rejected for restoration programs in Oklahoma, because no one could determine if they were genetically identical to the extirpated paddlefish that had existed in Oklahoma. Cutthroat trout from an adjacent watershed have been rejected for restoration programs because of minor, non-functional genetic differences. Populations of feral horses and feral donkeys are protected, but self-sustaining populations of rainbow trout have been eradicated because they were not native to the area 500 years ago. Fish farmers have been prosecuted for “allowing” small numbers of their fish to escape, but no hog farmer has been even investigated for allowing hogs to escape. The same complaint can be made with respect to turkeys. The list of examples can go on, and on, and………… What is to be done? Manage what we have, not what we wish we had… and recognize the cold hard facts that the aquatic ecosystems we have today are just as different from their historic predecessors as their terrestrial counterparts are different from their predecessors.
VIRAL HEMORRHAGIC SEPTICEMIA VIRUS SURVEILLANCE IN COLORADO With detection of viral hemorrhagic septicemia virus (VHSV) in the Great Lakes in 2005, the USDA Animal and Plant Health Inspection Service (APHIS) has been involved in nationwide surveillance for this disease. This virus appears to have mutated from strains that affected marine fish; the strain found in the Great Lakes is called Type IVb, and is the strain for which most surveillance efforts have been directed. VHSV can have devastating effects on a wide variety of species of fresh-water fish, with disease ranging from cases of acute high mortality to low-grade infections and carrier states. In 2008, the state of Colorado entered into a Cooperative Agreement with the USDA-APHIS and received $45,000 to conduct statewide surveillance for the virus in free-ranging fish. From May 21 through November 4, 2008, 4,121 fish from 20 major watersheds within the state were sampled, and no VHSV was detected in any of the samples. Monies were not available from USDA-APHIS for further surveys in 2009, and grants were delayed in 2010. However, another $30,000 was obtained in 2011 for continued surveillance within the state. In this latest grant, greater latitude was given to the cooperators (Colorado Parks and Wildlife) for use of the money. It was decided that one priority would be to perform surveillance testing in watersheds not sampled in 2008. In addition, frozen baitfish were tested for the virus, and an educational brochure was developed for state-wide dissemination. In 2011, 928 samples from free-ranging fish in six major watersheds were collected under the APHIS grant. In addition, 606 fish from seven major watersheds, including two fish kills, were tested for VHSV by the Colorado Parks and Wildlife Aquatic Animal Health Lab (AAHL), independent of the APHIS grant. No VHSV was detected in any samples. The AAHL also performed testing for largemouth bass virus on samples of tissues from appropriate species of fish, and there were no detections of that virus. It is important to point out that in addition to the free-ranging VHSV testing, all public and private aquaculture facilities in the state receive annual disease testing, which includes VHSV, and there have never been detections in that sector. A concern exists about the use of frozen baitfish imported from the Great Lakes. It has been proven that the VHSV virus can be detected in fish that have been frozen, but questions remain about whether the virus is still capable of replicating and causing disease in bodies of water where these baitfish are used. Frozen rainbow smelt (Osmerus mordax) from the Great Lakes are readily available in grocery and angling stores in Colorado, and are used as bait by fishermen throughout the state, particularly for ice-fishing. Therefore, as part of the APHIS grant, 180 samples from frozen Great Lakes smelt were tested for presence of the virus via molecular methods. No virus was detected, but the sample number was small. Statewide surveillance is very important, but angler education is extremely useful in order to try to prevent introduction of this virus into the state. Toward that end, an educational brochure was produced which covered information about clinical signs and how to report moribund or dying fish; restrictions for movement of fish, bait and fish offal; and proper disinfection techniques. Ten thousand copies were sent to all Colorado Parks and Wildlife offices, commercial angling/bait shops that sell fishing licenses, professional fishing guide services, and other stakeholders. A copy of the brochure can be found on the Colorado Parks and Wildlife website at http://wildlife.state.co.us/SiteCollectionDocuments/DOW/Fishing/AAHL/ViralHemorrhagicSepticemiaBrochure.pdf. Colorado Trout Unlimited disseminated copies to their membership. Continued surveillance of free-ranging fish is important as early detection is the best method by which to contain an outbreak. Currently, no funds are available from the USDA-APHIS for surveillance efforts in 2012. However, the Aquatic Animal Health Lab will continue to test for this virus at all private, public and free-ranging sites during annual health inspections, and for unexplained fish-kills in the state. All live fish entering the state must have a current health certificate indicating that the fish have tested negative for the virus. For additional information, contact Bill Manci |
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