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articles from March, 2006 newsletter:
How did you enjoy the early Spring in January weather? Isn't it typical Minnesota weather? It's like rolling the dice, you just don't know whether it's going to be hot or cold. That's the major reason I don't play the Craps, Slots, Black Jack or Poker! Well, maybe the nickel slots once in a while and when I lose my roll of nickels I quit. I tend to stick to games like Bridge and Mah Jonng that give you a chance of figuring the odds. Oh well, this weather should help with the heating bills at least! As I sat in front of my computer today, I thought back to the issues that are threats to the health of Lake Vermilion. It is in our club charter to protect the health of the lake we love. Some will say that we are anti-development. We realize that development is occurring and will continue to occur no matter what we do. We are attempting to educate those who develop their properties to take the precautions necessary to protect the lake. We need to convince the doubters that the manner in which they develop their property can be friendly to the lake or cause irreparable harm. Granted the harm caused may not be readily evident, but rest assured it will eventually surface. An old adage says: "An ounce of prevention is worth a pound of cure." This is definitely the case here at Lake Vermilion and is actually being seen as the case throughout Minnesota. Lake Associations on lakes that have been overdeveloped are experiencing the problems of declining water quality, increasing pollution, and increasing costs in rehabilitating those lakes. In order to learn more about statewide problems and help avoid those problems, the Board of Directors has voted to join the "Minnesota Waters" Association (a merger of the Minnesota Lakes Association and the Rivers Council of Minnesota). I'm sure that many of our SCLV members are already members of this organization. We will have more information in our next newsletter. The EIS for the U. S. Steel Minntac proposed tailings water discharge was approved by the MPCA Citizens Board last November 22 and the proposal now moves into the permitting process. We will continue to follow the progress and work towards getting U.S. Steel to clean up their act (and water) and act as the responsible citizen of our "Iron Range" that they profess to be. The U.S. Steel proposed development called the "3 Bays on Vermilion" along Mattson, Cable and Armstrong Bays, is in the EIS stage. We will continue to participate in trying to make sure this proposal meets the Tower-Breitung Management Plan and the proposed Lake Vermilion Management Plan. We firmly believe that meeting the plans' provisions will have minimal impact on the bottom line for U.S. Steel and greatly improve their image with present Lake Vermilion property owners. The Lake Vermilion Management Plan is still being massaged by the St. Louis County Planning Commission and is nearing the point of being presented to the Commissioners. My best guess is that it will be another year before final adoption. I hope I'm wrong! At the last Planning Commission meeting/hearing in January, several property owners presented their specific fears that they would not be able to achieve their plans. Hopefully they came away from that meeting assured that their fears were unfounded. Yes, there will be some instances where they may be restricted in how the development proceeds, but not in what they actually plan to achieve. They may have to use specific precautions in how the clearing, grading, excavation and construction is done and what mitigation measures must be used after construction is complete to minimize harm to the lake. In any case, they still must follow the rules in effect at the time their property became a lot of record. We are planning to expand our "Invasive Species" inspections/education program to encompass Resorts and Fishing Tournaments. Bob Wilson is heading up this effort and we will most likely be calling for more volunteers as it grows. More on that later. I want to thank all of you who have corresponded with me regarding spicing up the annual meetings. Rest assured that these suggestions have been read and have been given to the committee we set up to handle changing the format and content. If you have more suggestions, please send them in! I hope all you ice fishermen and fisherwomen have had good fishing this season. I haven't seen too many houses on our bay this year but then we never do. I haven't been out yet due to other pressing projects! Still some time left, so maybe!!! Speaking of correspondence, please keep all those cards and letters coming. We need to know what we're doing right and also what we are missing! The good comments boost our morale and the criticisms make us strive harder. Thanks again for your support and for making this such a wonderful club! To a better Club and Vermilion! Walt Moe, President By John Zwieg Starting May 15th there will be a new walleye regulation with a slot limit and number of walleyes caught daily on Lake Vermilion. All walleyes between 17 inches and 26 inches must be returned to the lake, and the new daily limit will be four walleyes, with one walleye over 26 inches allowed in your limit of four. This was done because the DNR found that the number of walleyes taken from the lake was exceeding the safe level of walleye production. Also, each year the fishing pressure is increasing with more people trying to catch the elusive walleye. In my opinion, I feel this is a great step forward for Lake Vermilion. In the 21st century fishing and fishing attitudes have to change to preserve the great sport of fishing. For many years the DNR and SCLV have been strong advocates of "catch and release." While this is an effective approach for maintaining a strong fish population, we need to have all anglers following the same rules. In my conversations with people who fish Vermilion and other lakes, almost all agree that the attitude of returning large fish back to the lake is a responsible act of conservation. Oh sure, there are still some who feel that they are entitled to keep any fish that are caught. I respect their feelings because I also felt that way not too many years ago. But as time goes on we must be willing to adapt and change our views on fishing if we want to have future generations enjoying catching sizable fish. I think our neighbors to the north in Canada have found this to be true in their conservation lakes. Resort owners there claim the secret to their success is the "slot limit" and number of fish taken from their lakes. Last fall while walleye fishing on Niles Bay, I was catching a few fish between 12 inches and 14 inches. Changing to a different color jig, I landed a 26-inch walleye. After measuring the fish and admiring my fine catch, I held the fish in the water stroking its belly and suddenly it flapped its tail and splashed water in my face (as if to say thanks) and swam away. A fisherman in a boat not far from me gave me a "thumbs up" sign. It was a feeling that I will never forget. I know that by releasing that fish some other fisherperson may someday experience a terrific catch. Over the years walleye fishing on Lake Vermilion has been good and even great somedays. Hopefully, if everyone follows the new guidelines, our grandchildren's children can say, "I love fishing on Lake Vermilion." 'INVASIVE SPECIES' ... by Bob Wilson It s not too early in the season to again start thinking about aquatic Invasive Species. Since zebra mussels have been discovered in Mule Lacs Lake, the potential for the transfer of these barnacle-like creatures to Lake Vermilion and other nearby lakes has substantially increased. It is my understanding that the DNR is going to more thoroughly inspect the boats exiting Mule Lacs in 2006. That should help, but we know some trailer and boat "carriers" will still slip through. In the next issue of "the vermilion sportsman" we will provide a detailed article on zebra mussels. However, the first step in preventing the spread of any of the exotics is to develop an attitude of concern. Second, we need to accept the fact that our collective activities are a potential means of transportation. As soon as you or your neighbors and friends trailer your boats from another lake to Lake Vermilion, the potential exists for an Invasive Species implant. Of course you know the drill by now. Always remove all visible vegetation from all of the equipment that was in the water, including boat, trailer, motor, fishing gear, anchor and anchor rope, etc. Air dry the boat for five days before using it in uninfected waters. If the boat and equipment are completely dry for two days, it may be safe to use but, keep in mind that zebra mussels may survive up to two weeks out of the water. More on zebra mussels coming next time. Below is Part II of the article on rusty crayfish continued from the November 2005 "Vermilion Sportsman." FOOD HABITS Crayfish are considered opportunistic feeders. Rusty cray- fish feed on a variety of aquatic plants, benthic invertebrates (like aquatic worms, snails, leeches, clams, aquatic insects, and crustaceans like side-swimmers and waterfleas), detritus (de- caying plants and animals including associated bacteria and fungi), fish eggs, and small fish. POTENTIAL IMPACTS Rusty crayfish may cause a variety of negative environmen- tal and economic impacts when introduced to new waters. First, they are an aggressive species (Munjal and Capelli 1982) that often displace native or existing crayfish species. Displacement of crayfish, such as 0. virilis and 0. propinquus, has occurred in many northern Wisconsin lakes, northern Ontario, and in the Kawartha Lakes region of southern Ontario (Capelli 1982; Lodge et al. 1986; Olsen et al. 1991). Rusty crayfish displace other crayfish species through a combination of crayfish-to-crayfish competition and increased fish predation (DiDonato and Lodge 1994; Garvey et al. 1994; Hill and Lodge 1993). The reason for increased fish predation on native cray- fish is two-fold. First, rusty crayfish force the native species from the best daytime hiding places and second, native crayfish try to swim away from a fish attack, which makes them more vulnerable. Rusty crayfish, on the other hand, assume a claws-up defensive posture which reduces susceptibility to fish predation. Perhaps the most serious impact is the destruction of aquatic plant beds. Rusty crayfish have been shown to reduce aquatic plant abundance and species diversity (Lodge and Lorman 1987; Olsen et al. 1991). This can be especially damaging in relatively unproductive northern lakes, where beds of aquatic plants are not abundant. Submerged aquatic plants are important in these systems for:
Rusty crayfish, especially juveniles, feed heavily on benthic invertebrates like mayflies, stoneflies, midges, and side-swimmers. It has been estimated that rusty crayfish might consume twice as much food as similar-sized 0. virilis because of a higher metabolic rate (Momot 1992). So, rusty crayfish are more likely to compete with juvenile game fish and forage species for benthic invertebrates than are native crayfish species. Displacement of native crayfish by rusty crayfish, therefore, could result in less food for fish. Crayfish are eaten by fish, but because of their thick exoskeleton (shell) relative to soft tissue, their food quality is not as high as many of the invertebrates that they replace. Less food or lower food quality means slower growth, which can reduce fish survival. Finally, it has been suggested that rusty crayfish harm fish populations by eating fish eggs. While rusty crayfish have been observed to consume fish eggs under various circumstances (Horns and Magnuson 1981), there is no scientific study directly linking fishery declines with crayfish egg predation. It's likely that those fish species that lay eggs in relatively warm water (greater than 50 F) are more susceptible to crayfish predation than fish that spawn during colder water periods (Momot 1992). For instance, warm-water spawners like smailmouth bass, largemouth bass and sunfish are more likely to be affected than cool-water spawners like lake trout, walleye or northern pike. However, Wisconsin DNR Fisheries Manager Harland Carlson has observed actively feeding crayfish during lake trout spawning in November (water temperature 46 to 50 F). Reduced reproductive success of walleye in Lake Metonga, Wisconsin was reported following the rusty crayfish invasion (Lodge et al. 1985); however, walleye reproduction in other Wisconsin lakes invaded by rusty crayfish was not similarly impacted. Perhaps the lower quality walleye spawning substrate of Lake Metonga compared to other lakes invaded by rusty crayfish allowed the impact on walleye reproduction. However, there is no evidence proving or disproving this speculation. Male bass and sunfish protect their nests until the eggs hatch and the advanced fry swim away. Dr. Bill Swenson, University of Wisconsin-Superior fishery scientist, has observed rusty crayfish attacking bluegill nests guarded by males. He also observed rusty crayfish in other unguarded nests. It is not known, however, if rusty crayfish caused the bluegills to abandon their nests or if they eat bluegill eggs on a regular basis. No detailed research has been done that proves rusty crayfish cause declines in fish populations. Observations and circumstantial evidence gathered by Wisconsin fishery managers suggest that bluegill and northern pike populations frequently decline following introduction of rusty crayfish (Harland Carlson and Chris Sand, Wisconsin DNR, per. Comm. 1994). Smallmouth bass in Lake Lenore and largemouth bass in Pounsford Lake, Ontario also seemed to decline following introduction of rusty crayfish (Dr. Walter Momot, per. comm. 1994). Impacts on other fish species are not as obvious. The primary cause of bluegill, bass, and northern pike declines is probably reduced abundance and diversity of aquatic plants. Reduced food (such as mayflies, midges, and side-swimmers) and egg predation may also play a role. Because impacts and population abundance of rusty crayfish vary in lakes that appear similar, it is not possible to predict what will happen when they invade a new lake. Nevertheless, it is clear that rusty crayfish are an aggressive, unwanted exotic. Cabin owners on heavily-infested northern Wisconsin and Minnesota lakes have even stopped swimming because large numbers of rusty crayfish occupy their favorite swimming area throughout the day. They fear stepping on them and getting pinched by the large-clawed "rustys." Other crayfish species, even if abundant, are usually less conspicuous during daylight hours. CONTROL Many chemicals kill crayfish. Some even selectively kill crayfish; however, none are currently registered for crayfish control (Bills and Marking 1988). And, none selectively kill rusty crayfish without killing other crayfish species. Intensive harvest will not eradicate or control crayfish, but may help reduce adult populations and minimize some impacts. Some researchers have suggested that nuisance populations of rusty crayfish are the result of poor fishery management and that by restoring a healthy population of bass and sunfish, rusty crayfish would be less disruptive in some lakes (Momot 1984). The best method of control, however, is to prevent their introduction. Educating anglers, crayfish trappers, bait dealers, and teachers about the threats posed by rusty crayfish will help reduce the risk of spreading rusty crayfish to new areas. Should rusty crayfish be used to control Eurasian watermilfoil? Eurasian watermilfoil is an exotic plant that forms dense mats and adversely affects swimming, boating and fishing. The use of one exotic species to control another is highly discouraged without proper long-term studies. Rusty crayfish, as well as other crayfish, cut plant stems as they feed. Much of the plant then floats away. Since Eurasian watermilfoil spreads and reproduces by plant fragmentation, crayfish could accelerate its spread. Also, Eurasian watermilfoil is more likely to establish itself in areas where rusty crayfish have disrupted the native plant community. In addition, if a suitable biological control for Eurasian watermilfoil is found, rusty crayfish could interfere with its effectiveness (through predation). Since there is no research into the effectiveness of using rusty crayfish for Eurasian watermilfoil control, and rusty crayfish usually do not become abundant in the lakes most susceptible to Eurasian watermilfoil, their introduction would not likely have the desired effects. No one should introduce this species into any waters. IDENTIFICATION Identifying crayfish can be very difficult. Positive identification requires looking at a number of characteristics and having enough experience to interpret them. Here are some general, easily-observed characteristics that can be used to help you identify mature adults of four common crayfish species found in the Great Lakes region. (Other species found in the region include Cambarus diogenes, Procambarus acutus acutus, and in southern parts of the region Procambarus clarki). The following are general identification guidelines and should not be used when positive identification is needed. Contact your local fishery management agency or Minnesota Sea Grant if positive identification is required. Minnesota's Nongame Tax Checkoff: Help our wildlife at tax time Tax time is just around the corner. As Minnesotans fill out their tax forms this year, they will again notice Minnesota's state bird, the common loon, marking the contribution checkoff line for Minnesota's Nongame Wildlife Program. It's been there since 1981. Minnesota is one of many states that use a tax checkoff to fund nongame wildlife programs. It's the bald eagles, common loons, bluebirds and prairie voles that benefit from these donations. Game-animal management, research and habitat improvement are supported by the sale of hunting licenses and stamps, and the federal excise tax on sporting arms and ammunition. Nongame programs don't share in those funds. Thus, although Minnesota's Nongame Wildlife Program is part of the DNR Section of Wildlife, its projects and personnel are funded separately. The program depends almost entirely on voluntary donations, with most coming from the tax checkoff. In Minnesota, a handful of nongame specialists, spread throughout the state, conduct research and census work, initiate reintroduction and habitat-protection projects, and look after the interests of nongame species and their critical habitats. Nongame specialists also work with private landowners to protect nesting areas for owls, eagles, loons, and ospreys. They give educational presentations to school kids and civic organizations. They work with other resource managers in the DNR to integrate nongame needs into management plans for state forests, public waters, wildlife management areas and state parks. The Nongame Program has been responsible for the reintroduction of trumpeter swans and management efforts for species with particular needs like piping plovers, goshawks, wood turtles and sandhill cranes. The Nongame Program encourages all Minnesotans to "look for the loon" at line 27 on their tax forms this year and give what they can. Small contributions can make a big difference; in fact, contributors in the one-to-ten dollar range have been the mainstay of the program. For more information about nongame wildlife in Minnesota, contact the DNR Information Center, toll-free at 1-800-766-6000.
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