The official web resource of the
Colorado Aquaculture Association
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In 2009, the rusty crayfish, Orconectes rusticus, was discovered in Colorado in the Yampa River drainage between the towns of Steamboat Springs and Yampa. This is the first confirmed identification of this species in the state. This crayfish is listed as an aquatic nuisance species in Colorado and possession is prohibited. So why is such an innocuous creature as a crayfish prohibited? The rusty crayfish is native to Ohio, Kentucky, Tennessee, Indiana and Illinois, but has spread to other areas primarily through “bait-bucket” introductions. It is an aggressive species that can displace native crayfish, cause destruction of aquatic plant abundance and diversity, and prey on eggs and young of fish and amphibians. They are found in lakes, ponds and streams with silty to rocky substrates. They need permanent water and do not burrow during dry periods. It only takes one female carrying viable sperm to start a new population in a body of water. To most folks, a crayfish is a crayfish, but there are over 330 species in North America. We do not know the historic ranges or species of crayfish native to the east slope of Colorado because no surveys or identifications occurred until about 50 years ago. There are no crayfish that are native west of the Continental Divide in Colorado, so all crayfish found there have been introduced as non-native species. Currently, there are seven species that have been identified statewide (Walker, personal communication). Because crayfish are recognized as good forage for fish, introductions have been widespread throughout the state, but there are definite downsides to these introductions. Other sources of crayfish come from the backyard pond and aquarium industries and crayfish released from school projects and laboratories. Like all crayfish, “rusties” opportunistically forage on live or decomposing plants and other organic material, aquatic invertebrates, small fish and amphibians and their eggs, and dead aquatic organisms. Rusties, however, have a higher metabolism than most crayfish, and therefore their energy requirements are greater which leads to aggressive feeding. Whereas most species of crayfish are nocturnal, the rusty crayfish’s aggressiveness toward predators allows it to hunt and feed during the day, increasing its ability to out-compete other crayfish species. The rusty crayfish has several distinguishing physical characteristics. It gets its name from the rust-colored patches on either side of the body (right where you would normally grasp a crayfish to pick it up). The grayish-green to reddish-brown claws are robust and large in relation to the body and have a narrow black band near the tip. The moveable part of the claw is slightly S-shaped. The maximum total length is about four inches (not counting the claws) and they can live three to four years. Mature males can attain a greater size than most females. Despite these characteristics, accurate identification of crayfish depends on careful examination of many other physical features. Trying to identify crayfish by size or color alone is nearly impossible, as these characteristics change with age and sex of the crayfish, water quality, locale, and stage of molt. The rusty crayfish is considered a nuisance or invasive species due to its aggressive feeding and defensive behaviors, and through these mechanisms it can out-compete native crayfish species. They force other species of crayfish from their hiding places and into the open where they are at risk of predation. When threatened by predators, rusties assume a defensive, claws-up posture that discourages predators. Other species of crayfish flee from danger, putting them at higher risk of predation as they scuttle around in the open. Because of their voracious appetites, rusty crayfish can reduce or otherwise alter the abundance and species diversity of aquatic plants. These plants are important as food sources for fish, as habitat for invertebrates and young fish, as nesting areas for fish, and as erosion control. In mountain lakes where plant abundance is not high, this can be a threat to the balance of the entire system. There is anecdotal information that the rusty crayfish can alter fish populations by preying on eggs and driving fish from their nests, but this has not been proven. Once rusty crayfish are introduced into a body of water, they are extremely difficult or impossible to eradicate, depending on the size and type of aquatic system and the extent of the invasion. There is no chemical that selectively kills the rusty crayfish. Therefore, prevention of introduction is the only method to completely protect an aquatic resource against this invader. Also, few management options exist to control spread of the crayfish once it is established in an aquatic system. Trapping programs can decrease numbers, but does not eliminate all rusties from a system. After the rusty crayfish was discovered in Colorado, The Director of the Colorado Division of Wildlife, per Wildlife Commission Regulation Article XI-020-E-6, ordered that a closure be established and enforced in the Yampa River basin from its headwaters downstream to the Colorado-Utah state line, including all tributaries, reservoirs, lakes and canals. This closure states that all crayfish must be returned to the water of origin immediately or killed and taken into possession immediately upon catch with kill being effected by separating the tail from the body, beginning 12:01 a.m., April 10, 2010, and extending through 11:59 p.m., December 31,2010. If you suspect rusty crayfish, please contact Elizabeth Brown, Pete Walker or Carolyn Gunn from the CDOW Aquatic Health Lab at elizabeth.brown@state.co.us, pete.walker@state.co.us or carolyn.gunn@state.co.us.
Regulations are necessary in a modern world. There are simply too many humans and our “advanced” technologies have too many known, and unknown, effects on other humans and the environment upon which we all depend to let everyone “do their own thing.” My rights end where yours begin. We just cannot turn back the calendars to those past centuries when there were few humans, natural resources were relatively unexploited, and life was simply a matter of day-to-day survival. However, even though I accept the necessity of regulations in general, I do not accept the regulatory mess with which fish farmers must contend as they attempt to move their products to willing buyers. We can do better. We must do better. Colorado and the fish farmers in Colorado have one big advantage with respect to water and regulations pertaining to water: everything is downhill from Colorado. With the minor exceptions of a short reach of the Little Snake River and a few miles of a loop in the Green River in northwest Colorado, no water flows into Colorado from another state. This means that Colorado doesn’t have to deal with gaps in the regulations of other states, at least with respect to waters flowing in. Colorado authorities can focus on whatever regulations are needed to control problems within the state. Unlike Las Vegas, what happens in Colorado does not stay in Colorado, at least when water is the matter under consideration, because water from Colorado flows directly into seven other states. Even within the scope of appropriation rights, Colorado has some responsibility for the effects of its regulations on everyone located downstream. However, for fish farmers the primary effects of regulations are related to movement of fish, not the flow of water. The further the fish need to move, the greater the number of regulations and the greater the problems with regulations. By-and-large, Colorado authorities have done a good job with regulations, at least with respect to matters affecting fish farmers; although there is some grumbling about regulations pertaining to inter-basin movements of fish within the state. Movements of fish into the state from downstream locations or from other areas of the country, are the focus of most regulations and the main focus of complaints. Concerns about the movement of fish disease agents and the introduction of non-native fish and/or aquatic nuisance species are the basic factors that lead to regulations. In my experience, the biggest flaw in the regulatory systems is the fact that regulations are always applied within the limits of political boundaries and rarely consider river basin or ecological boundaries. To be effective, Colorado regulations applying to the Platte River system must be coordinated with Wyoming and Nebraska. Similar coordination is required with downstream states in the Colorado River system, and the Rio Grande, and the Arkansas. Within each state, there is a tendency to produce regulations on a “one size fits all” basis. Unfortunately, what is best for the Rio Grande system may not be best for the Platte system. Another factor that “helps” to produce “regulatory chaos” is the fierce belief by state authorities (a.k.a. regulators) in their “states’ rights.” In the case of fish, when they are considered to be wildlife, our federal constitution is clear; fish are considered the property of the state and the state has regulatory authority. (I like to remind state officials that they have authority and a responsibility, not a right, to manage and regulate wildlife.) But, what about fish that have spent their entire life in captivity and are the property of a fish farmer; aren’t they livestock and aren’t they subject to regulation by departments of agriculture? Some states have “solved” problems related to fish as wildlife versus fish as livestock by making fish farmers subject to regulation by both agriculture and natural resource agencies. The result of such “solutions” is myriad, differing regulations. A fish farmer trying to supply a national market can easily be subject to more than 50 sets of ever-changing regulations. If international commerce is involved, it gets even more complicated. There must be a better way. I think there is, but it would mean sacrificing some of those fiercely protected “States Rights.” To be effective regulations concerning fish and fish disease agents must be managed and regulated on a river basin or watershed basis. The waters and the biota in them are an interconnected system; the regulations applied to them need to be based on the same system. But, how can we apply such a system when the river basins involve more than one political entity and, thus, more than one jurisdictional authority. There are several ways to accomplish the desired goal, but authorities must first agree that they want to solve the problem, even if it means giving up a bit of their authority. The simplest way to accomplish management based on river basin boundaries rather than state boundaries is to agree to have federal management. In Canada, authority for fisheries management rests with the federal government, unless specifically given to the separate Provinces. It is unlikely that the U.S. Constitution will be modified to retain authority for fisheries management at the federal level, but states could voluntarily enter into basin-wide compacts that would provide federal managers the authority to manage selected aspects, such as introductions of non-native species and fish health regulations. Another model that has worked for a variety of fisheries and water issues is to enact federal legislation that requires states to develop basin-wide management compacts by a certain date. If the states fail to do so, the federal government will step in, develop management strategies and regulations, and implement these approaches until such time as the states develop their uniform regulations. The National Aquatic Animal Health Plan (NAAHP), which has been in development since the early 1990s, is basically a good plan; however, implementation is voluntary. The plan is a set of guidelines. In some situations, such as the recent spread on viral hemorrhagic septicemia in the Great Lakes region, the USDA Animal Plant Health Inspection Service (APHIS) has provided the uniform leadership necessary for a coordinated response. However, a uniform system covering all disease agents of concern and all non-native species of concern is needed. If each jurisdiction is free to establish its own regulations, standards, and implementation guidelines, we still have the overall chaotic and ineffective system that we have at present. To ensure sufficient uniformity in the design and implementation of management strategies, regulations, and testing protocols to allow for certification and movement of products, the standards developed by the OIE (World Organization for Animal Health – Aquatic Animal Commission) could be used. Individual jurisdictions would remain in control of their areas, and could respond to unique situations in their area. However, adoption of common standards and methods for all reportable disease agents and banned non-native species would eliminate most of the variations that exist from jurisdiction to jurisdiction at present. Another aspect of standardization would be to require all individuals and laboratories conducting sampling and testing to be certified; and to undergo periodic reviews; to ensure that they operate at the levels required by the standards. During my time as a fish health administrator in the U.S. Fish and Wildlife Service (USFWS), I attempted to implement a systematic program of reviews for the USFWS Fish Health Laboratories, but was blocked from doing so by higher level supervisors. Even though such reviews are standard practice for certified veterinarian laboratories, these supervisors did not want the USFWS staffs to “feel threatened.” Yes, regulations are necessary. Yes, uniform standards and methods are necessary. Yes, certification is necessary. Different regulations, standards and methods that vary widely, and wildly, across political boundaries are ineffective in maintaining fish health and protecting natural resources. The evidence is overwhelming that the absence of uniform standards and procedures that address health issues of common concern and recognize natural boundaries rather than political boundaries, has created a mess that constrains legitimate commerce and does little to protect natural resources. We must give up a bit of jurisdictional independence in order to address the problems. For additional information, contact: Bill Manci |
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