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HARMFUL NONINDIGENOUS SPECIES INTRODUCTION Nonindigenous species are those not native to a specific area and introduced by humans. They are sometimes referred to as non-native species or exotic species. Some are considered pest, nuisance, harmful, or invasive species. Schmitz and Brown (1994) refer to these species as "anthropogenic pollution." Invasion by nonindigenous species originating from throughout the tropical-subtropical world is a major threat to South Florida natural areas. Many nonindigenous plant and animal species have escaped cultivation and become established in the Region. Nonindigenous plants and land animals constitute about 25% of all species in the State as a whole (OTA 1993). Some have not only colonized disturbed sites but also invaded natural lands set aside for preservation of natural communities and landscapes. South Florida itself probably has more problems with aggressive nonindigenous species than any other entire State. Economic, as well as ecologic, problems arise from invasions by nonindigenous species. Many agricultural pests, marine fouling organisms, and aquatic weeds are nonindigenous species. Loss, through exotics infestations, of the natural characteristics that draw visitors to South Florida from all over the world can be expected to result in further economic losses. Problems caused by invasive nonindigenous plant species are particularly noticeable. Florida as a whole has approximately 925 established nonindigenous plant species growing outside of cultivation (OTA 1993). Over 100 of these are listed as invasive in Florida by the Florida Exotic Pest Plant Council (FLEPPC 1995). Melaleuca (Melaleucaquinquenervia) and Brazilian pepper (Schinus terebinthifolius) are well-known examples of harmful nonindigenous trees that are widespread and expanding their coverage in South Florida. At least 23 nonindigenous plants are now found in Florida waters (McCann et al. 1995). Many nonindigenous animal species have become established in Florida's aquatic systems: 83 fish, at least 26 insects since 1970, 2 amphibians, 3 birds, 1 mammal, 1 reptile, 5 mollusks, 1 crustacean, and an unknown number of pathogens (McCann et al. 1995). Many nonindigenous terrestrial animals, particularly birds, reptiles, and amphibians, have escaped captivity and are reproducing in South Florida (McCann et al. 1995; Robertson and Frederick 1994). Of the introduced nonindigenous bird species in the continental U.S., 63% are in Florida. Florida also has the largest number of established nonindigenous amphibians and reptile species in the U.S. (OTA 1993). Insects undoubtedly are the most numerous animal immigrants to Florida. At least 946 arrived without purposeful human help, often as hitchhikers on cargo, especially plants (Frank and McCoy 1994). The best-known problem insects are those that have caused harm to humans and economic crops. Those that harm natural systems are less known, but could be numerous. A recent concern is the weevil Metamasius callizona, which kills all three of Florida's native bromeliad genera (Tillandsia, Catopsis, and Guzmania) in natural areas (Frank and Thomas 1994). This insect appears to be expanding fast, and there is concern it may soon reach the Fakahatchee Strand, an important area for conservation of native bromeliads (J. Frank, UF, pers. comm.). South Florida is particularly vulnerable to invasion by nonindigenous species for a variety of reasons (Simberloff 1994), including insularity and the extent of habitat disturbance by humans. Coupled to this are South Florida's mild, generally frost-free climate, which makes it a mecca for persons growing tropical plants and animals, either commercially or as a hobby. Furthermore, Miami is port of entry for plants and animals arriving in the U.S. from all over the world. Of all plant shipments into the Nation, 85% pass through Miami (Simberloff 1994). 38 NONINDIGENOUS SPECIES BACKGROUND Description of the Problem Nonindigenous plants negatively impact native habitats by outcompeting natives, decreasing species diversity, and altering topography and soils. Nuisance plants significantly reduce available native habitat for several Federal endangered species. Dense monocultures formed by melaleuca replace native vegetation and thus decrease nesting and foraging habitats for endangered species such as the snail kite and Cape Sable seaside sparrow. Aquatic plants such as hydrilla (Hydrillaverticillata), water lettuce (Pistia stratiotes), and water hyacinth (Eichhornia crassipes) clog streams, rivers and lakes. These aquatic weeds create a continual problem by obstructing navigable waterways throughout the Kissimmee-Okeechobee-Everglades system. Millions of dollars and extensive labor are spent each year to reduce these impediments. Herbicides are frequently used to prevent clogging of waterways and lakes. Therefore prolific nonindigenous plants are indirectly responsible for the application of tons of chemicals to Florida waters. Prolific animal species that have escaped to the wild may degrade habitat quality for native wildlife, introduce diseases or pathogens, or outcompete or prey on native species. In many locations non-native herpetofauna (e.g., Anoles segrii) have replaced native congenitors (e.g., Anoles carolinensis). Cichlid fish species have invaded ENP and appear as dominants of the aquatic fish community in visitor areas such as the Anhinga Trail. Cichlids also are common components of the brackish-water fish community in coastal areas of the Park adjacent to northeastern Florida Bay (Lorenz 1993). The escape from captivity of nonindigenous fish is a particular concern because of Florida's extensive, unique, internationally recognized wetlands. South Florida's low natural diversity of freshwater fishes is one factor that has made it vulnerable to invasion by nonindigenous fish. South of Lake Okeechobee, nonindigenous species already make up over 50% of the inland fish fauna (Courtenay 1994a). Disturbance enhances establishment of nonindigenous fish because they often are more tolerant of disrupted habitats than are native species. Because any fish species varies morphologically and ecologically at different stages of its life cycle, nonindigenous fish can affect native fish differently at each life stage. Invasive nonindigenous fish are a threat to native fish populations. Although there have not yet been any known extinctions, Warren and Burr (1994) concluded that the southeastern U.S. soon will equal or exceed the American west in the number of threatened and endangered fishes. Non-native plant and insect pests in South Florida that attack economic crops, lawns, and golf courses have led to widespread application of pesticides for their control. For instance, infestation of turf grass by South American mole crickets (genus Scapteriscus) is a primary reason for the high pesticide applications on golf courses (Frank 1994). These pesticide applications degrade water quality and cause environmental damages. Not all nonindigenous species are harmful. Many nonindigenous ornamental plant species never escape cultivation. Not even all species that spread beyond their planting site are invasive. In South Florida, however, the potential for harm to natural areas from even one invasive plant species is enormous. For instance, melaleuca, introduced in the early 1900s, now infests roughly 450,000 ac (703 mi2) of South Florida to some degree (OTA 1993). At least 50,000-60,000 ac (78-95 mi2) of melaleuca are growing as a monoculture (R. Doren, ENP, pers. comm.). Past experience and a study on the rate of expansion indicate the uncontrolled trees could overtake most of the remaining wetland areas south of Lake Okeechobee within 30 years (Bodle et al. 1994). A virtually uncontrolled expansion of nonindigenous species is altering the South Florida landscape and affecting the functioning and biological integrity of the ecosystem. Melaleuca is just one example of the many species rapidly expanding in South Florida natural areas. Because the rate of expansion increases with time (Laroche and Ferriter 1992), it is important to control species such as melaleuca at early stages of infestation of a site. A coordinated, integrated multispecies science program is needed to develop information and techniques to control invasions by nonindigenous plants and animals that have already escaped cultivation and prevent introduction of new invaders. Lack of effective control efforts at early infestation stages is a major issue. 39 NONINDIGENOUS SPECIES Existing Efforts A comprehensive review and analysis of the effort to control harmful nonindigenous species recently was published by OTA (1993). Many needed science topics can be gleaned from that document, which includes a special section on Florida. The FLEPPC is a nongovernmental group formed in 1984 to address the dilemma of invasive nonindigenous plants in Florida. One major activity of this group has been to develop an extensive, prioritized list of harmful nonindigenous plants. The present list includes 115 problematic nonindigenous species (FLEPPC 1995). The FLEPPC has a research committee whose responsibilities are to determine science priorities, facilitate funding coalitions, and review research proposals. Progress has been made in developing effective methods for eradication of melaleuca on a local scale, and these methods are being applied in a coordinated effort in parts of South Florida. The Melaleuca Task Force was formed by several concerned entities that have joined together to systematically eradicate this species. As one of several working committees of the FLEPPC, the MTF is currently investigating and implementing several control operations and methods (MTF 1994). Several State agencies are involved in nonindigenous plant control. The SFWMD leads several exotic eradication efforts in South Florida. The FDOT continually reduces and selectively maintains invasive nonindigenous plants on rights of way. The UF is conducting research on biological control of Brazilian pepper. The FDEP has a long history of managing widespread invasive nonindigenous species on a regional basis. Its Aquatic Plant Management Program is based on maintenance control to reduce the requirements for chemical and other control efforts. Maintenance control, a concept that originated with the COE, is the process of maintaining a species at or below a prescribed percentage of cover (e.g., water hyacinth at 5%) through consistent efforts (Schmitz et al. 1993). This technique, applied to water hyacinth, substantially reduced herbicide usage and organic sedimentation. Because of maintenance control, water hyacinths now impact only 1000-1500 ac (1.5-2.3 mi2) annually, compared to 120,000 ac (187 mi 2) in the 1960s (D. Schmitz, FDEP, pers. comm.). Maintenance control has also been effective with water lettuce, but not with hydrilla (Schmitz et al. 1993). Federal agencies have many ongoing exotic control projects. The COE supports many exotic removal programs. The NPS is involved in control of melaleuca, Brazilian pepper, Australian pine (Casuarinaequisetifolia), shoebutton ardisia (Ardisia elliptica), and other species in the National parks and preserves. The FWS is responsible for control of exotics in National wildlife refuges. Local governments also have exotic removal efforts. County park and recreation agencies have concentrated on removing invasive non-native plants from natural areas throughout South Florida. Dade County has a multimillion dollar exotic control program to help tropical hammock areas in county parks recover from invasions by nonindigenous plants and some prolific native vines after Hurricane Andrew. Several Federal laws deal with importation of nonindigenous species. The Nonindigenous Aquatic Nuisance Prevention and Control Act of 1990 and the Lacey Act authorize the FWS to issue regulations on aquatic and other nuisance species and restrict importations of exotic species. The APHIS also has responsibilities under the Lacey Act and administers the Federal Noxious Weed Act of 1974 and the Federal Plant Pest Act. Its responsibilities include identification of actual or potential noxious weeds and prevention of their entry into the U.S. (OTA 1993). These various laws as administered, however, have not been effective in preventing the importation of nonindigenous species potentially harmful to natural ecosystems (OTA 1993). Only a few groups are actively involved in scientific investigation of nonindigenous species that threaten natural areas. In particular, these include the ARS, SFWMD, COE, and NPS. The SFWMD has established herbicidal evaluation plots on several invasive plant species throughout the Region. The NPS has conducted studies on methods to restore natural communities on rockplowed fallow farmland and prevent repeated reinvasions by nonindigenous species after their removal (Doren et al. 1990). The COE funds research on control of aquatic weeds and melaleuca. The ARS and UF are investigating various biological control organisms on several nonindigenous 40 NONINDIGENOUS SPECIES plants, including melaleuca and Brazilian pepper. Host-specific organisms are tested for their effectiveness as control agents and for their general safety. The introduction of host-specific insects, such as seed and sapling eaters, can safely and economically decrease the spread of pest plants. Predatory insects, parasites, or pathogens can be used to control the spread of insect pests, if appropriate host-specific organisms can be found (e.g., see Frank 1994). Considerable progress has been made on identification and testing of a biological control agent for melaleuca. The proposed ARS quarantine facility in Fort Lauderdale will be used to expand investigations of the potential use of insects or plant pathogens to control or reverse expansion of invasive nonindigenous plants. The Federal Interdepartmental Committee for Management of Noxious Weeds was formed recently and is made up of many agencies within the Departments of Interior, Transportation, Energy, and Agriculture. This group is responsible for coordinating noxious weed management. One objective is to reorient the emphasis of control efforts toward protecting natural lands and rangelands, not just croplands. This may eventually lead to allocation of more research dollars to the protection of natural areas. Publication of the OTA report (1993) on harmful nonindigenous species was a major advancement because it provides an overview of the problem and the present institutional framework for addressing it, as well as an evaluation of program effectiveness. Problems specific to Florida were examined in a recent report by the FDEP (Schmitz and Brown 1994). The NPS is planning a similar report for its units. Recently the COE (1995) completed a report that recommended the integrated use of mechanical, physical, biological, and chemical methods to control melaleuca. The exact combination of methodologies used at a given site will depend upon the treatment, population density of melaleuca to be removed, and status of the existing natural system. Several combinations of methods, including that proposed by Woodall (1980), currently are under review. MAJOR ISSUES The major issues in South Florida related to nonindigenous species are: > > > Inadequacies in funding for scientific investigations that will lead to development of effective controls. Lack of funding to apply control methods to problem species. Delays and lack of consistency in responses to new problems. Scientific study on exotic species in Florida has been underfunded, considering the magnitude of the problem and potential for further damage to the ecosystem. Most resources have been focused on agricultural pests and aquatic weeds. Little has been spent on investigations of exotic species that threaten natural areas. Three interrelated lines of scientific inquiry are particularly needed: > > > Studies to develop control technology. Basic biological and ecological studies to improve understanding of invasive exotic species. Screening and risk assessment technology. With respect to control technology development, biological controls must be identified, tested, and distributed; environmental controls must be hypothesized and examined; mechanical or manual removal and herbicidal application strategies must be designed and applied and results of applications tested; and habitat restoration strategies must be treated as experiments in which follow-up data are collected and analyzed. Basic biological and ecological investigation is essential to the overall control effort. Such efforts will not only help develop greater understanding and perspective but also help design details of control methods; e.g., which biocontrol agents would be most effective, when to apply herbicides for maximum effectiveness. Screening and risk assessment technology could help focus control efforts on the greatest potential problems. All three lines of investigation are vitally important to the South Florida Ecosystem Restoration effort. Biological control is a well-developed science. The simplest definition, paraphrased from Center et al. (1994), is "the introduction of a pest's own natural enemies (parasitoid, predator, or pathogen) from the pest's native 41 NONINDIGENOUS SPECIES environment to a new environment in which the pest has become established." Biocontrol has been successfully applied to control of agricultural pests and aquatic weeds throughout the U.S. and in other parts of the world (Center et al. 1994). Recent successes include control of alligator weed in the southeastern U.S., including Florida. There is an extensive protocol to ensure a selected control agent will not only be effective against the chosen target but also will not affect nontarget organisms in the new environment. Biologic control is the possible means of control in certain cases (e.g., to control the Mexican weevil attacking native bromeliads (Frank and Thomas 1994). Investigation of biological control, although it has made promising progress on several major invaders of South Florida natural areas, is inadequately funded, and other control methods alone cannot alone halt or reverse region-wide invasions. Biocontrol is an essential component of the control of melaleuca, Brazilian pepper, and other plant species already widespread in South Florida natural areas. Construction of the quarantine facility at Fort Lauderdale, an essential component of the ARS biological control program, is not yet fully funded nor are the staff and resources to operate the facility. The limited amount of biological and ecological information concerning invasive species affects the ability to generate funding or devise control strategies. Scientific efforts are needed to address the following questions: > How will water management alterations to restore the natural ecosystem affect nonindigenous plants and animals? > What are the principal controls on expansion of an invasive nonindigenous species in its place of origin? > What are the impacts of nonindigenous species on native species and ecosystems? > What are the major factors influencing expansion rates of specific problem species in South Florida? > What are the conditions that cause greatest stress to the invasive species at various life stages? > What factors make a natural area susceptible to invasion by nonindigenous species? > What are the seasonality of flowering, fruiting, and germination, as well as responses to environmental variables, that might allow a nonindigenous species to be controlled by management measures such as new water management or prescribed burning practices? > How do nonindigenous plant species that establish monospecific stands affect the water budget? For instance, does melaleuca consume more water, particularly during the dry season, than the native species it replaces? Addressing such questions would not only provide greater understanding for the need to control a species but would also provide insight to help design biological and environmental controls. Science-based screening and risk assessment methods concerning invasive nonindigenous species are lacking, but they are needed to prioritize species so the greatest threats receive the most attention. Risk assessment methods would help focus control efforts by pinpointing generic invasive characteristics that could be used to screen proposed introductions and exclude those with high invasive potential. This would provide a scientific basis for banning the import of certain species before they become a problem rather than after. Habitat restoration strategies are needed to prevent invasive nonindigenous plants from returning once they are removed from heavily infested areas. One general strategy is to replant native vegetation, but scientifically supported guidelines on how to most effectively reestablish native plant communities in South Florida are limited. Horticultural approaches to control of nonindigenous species are poorly explored. The development and widespread dissemination of sterile varieties of popular, but invasive or potentially invasive, nonindigenous species might prevent future invasions by such species. Sterile cultivars are very popular in other regions; e.g., cottonless 42 NONINDIGENOUS SPECIES cottonwood trees, fruitless mulberry trees, and podless locust trees in the Southwest. The feasibility and potential long-term benefits of developing sterile cultivars is worth investigating. In addition to their harmful effects on natural areas, many invasive nonindigenous species also are detrimental to agricultural lands. For instance tropical soda apple (Solanum viarum), a threat to natural areas, is becoming a serious agricultural problem in Florida. Even if controlled on agricultural lands, it will continue to reinvade unless infestations in natural areas also are curtailed. One recent immigrant, the weevil Metamasius callizona, that is threatening the survival of native Florida bromeliads, also attacks ornamental bromeliads and pineapple (Frank and Thomas 1994). The role of nonindigenous animals in South Florida natural areas is so poorly documented that it is difficult to design and mount an effective effort to control those that are harmful to native plant and animal communities. The major issue, therefore, is the lack of meaningful information concerning the effect of nonindigenous animals on Florida's native ecosystems. INFORMATION NEEDS The information needs critical to control of nonindigenous species are shown in Figure 4 as related to the restoration and scientific objectives. The recommended approach includes the following: > Prepare coordinated science programs on invasive or otherwise harmful nonindigenous species for inclusion in the separate multispecies management plans for plants and animals recommended by the South Florida Ecosystem Restoration Interagency Working Group (1994). The first step in development of each science plan should be to prepare a comprehensive review of recent and ongoing studies. State agencies, particularly the FDEP and SFWMD, should be involved in the process, as should FLEPPC. The programs should take a long-term view toward the problem of invasive nonindigenous species in South Florida and consider the problem in the context of the South Florida Restoration effort. Efforts should not be restricted to only studies of individual species, but rather should attempt to build a set of principles that helps support a holistic, ecosystem approach to exotics control. The questions listed under Major Issues above should be addressed. > Continue and expand investigations of biological control. (Suggested lead--ARS, COE) These must include: · · · · · · Foreign exploration - search for the most effective control species in the species' native land. Overseas screening process - determine the most effective and safest species before importing to the U.S. Quarantine follow up - clearance for field release. Onsite field sites - colonization in areas affected. Assessment of success and performance of introduced control species. Technology transfer - distribution of organism throughout range of invasive species. The quarantine facilities in Fort Lauderdale and Gainesville are critical components of the biological control effort. Funding must be provided to construct and operate the quarantine facility at Fort Lauderdale, improve and maintain the quarantine facilities in Gainesville, and provide support personnel for the Fort Lauderdale facility. Priority in biological control studies should be given to the greatest threats. > Conduct studies (Suggested lead--NBS) to develop ecological understanding of invasive nonindigenous species. With respect to nonindigenous plants, more work is needed to determine: · · Factors that affect invasibility of natural areas. Environmental requirements and phenology of each problem species as these relate to their vulnerability to specific prescribed burning or water management regimes. 43 Planting approaches that lead to establishment of native ecosystems with low invasibility. Planting approaches that discourage reinvasion by exotics. Develop effective restoration methods that discourage reinvasion by exotics. Interactions with native species. Relationships with hydropattern and fire. Autecology of various exotics in South Florida. Determine and enhance natural controls. Effect of potential non-native control agents on native species. Environmental relationships in land of origin. Controlling insects/ pathogens in land of origin. Autecology in land of origin. Develop biological controls. Distributions of exotics in the wild. Develop multispecies monitoring plan. Effects of exotics on recovery of native ecosystems from natural disturbances. Impacts, by species, on native ecosystems. Effective control methods. Common characteristics of invasive exotics. Environmental requirements and phenology of problem species. Factors that affect invasibility of natural areas. Criteria for determining greatest threats and documenting problem species. Documentation of problem species. Develop multispecies management plan. Protect natural ecosystems from invasive exotic species. Status of exotics in natural communities. Halt and reverse spread of invasive naturalized exotics. Figure 4. Goal, objectives, and information needs for efforts on INFORMATION NEEDS SCIENCE OBJECTIVES RESTORATION OBJECTIVES RESTORATION GOAL HARMFUL NONINDIGENOUS SPECIES Technical approaches to assessing risk at entry, distribution, escape, early invasion stages. Develop screening and risk assessment methods. Horticultural experiments to create podless or seedless cultivars. Develop sterile cultivars of popular exotics that regenerate readily in South Florida. Prevent invasions by new exotic species. NONINDIGENOUS SPECIES · · · · Common characteristics of invasive non-native species in Florida. Effects of nonindigenous plant infestations on native species and the environment. Effective habitat restoration strategies to prevent reinvasion by nonindigenous species after their removal. Recommendations for implementing integrated pest management strategies. With respect to nonindigenous animals, scientific study is needed on impacts of these species on food webs, community structure, and populations of species in natural areas in which they have become established. For some taxa, such as insects, even more basic information is needed. Lacking, for instance, is an inventory of insect species (natives as well as known exotics) in South Florida. > Develop scientifically based methods for efforts to control invasions relatively early colonization). (Suggested leads--ARS, NBS, FGFWFC) screening in the and risk assessment to prioritize process (importation, distribution, Needed are effective criteria to identify and screen potentially invasive or otherwise harmful nonindigenous plants and animals before they become well established here or preferably even before they enter the U.S. Science activities should be integrated with prevention and eradication efforts. > Develop FWS, NPS) a multispecies monitoring plan for nonindigenous plants. (Suggested Leads--NBS, As part of plan development, existing monitoring programs should be inventoried and analyses made to determine overlaps and gaps in coverage. The plans should ensure that basic variables are defined and measured the same way so that data can be analyzed across areas, not just locally. Activities of the COVER Group should be supported and their efforts incorporated into the plant plan. A computerized atlas of ongoing monitoring programs should be prepared. The FDEP, SFWMD, FLEPPC, and county natural resource agencies should be major partners in plan development. > Develop FWS, NPS) a multispecies monitoring plan for nonindigenous animals. (Suggested Leads--NBS, Systematic monitoring of probable points of entry of nonindigenous species (Courtenay 1994b) should be a major provision of the animal plan. This is particularly important for fishes, because, once a nonindigenous fish extends its range beyond the point of introduction, eradication becomes impossible and control costs soar to prohibitive levels (Courtenay 1994a). A monitoring program is needed that can detect new introductions early enough for eradication efforts to be made before control is out of the question. The FDEP, FGFWFC, and county natural resource agencies should be major partners in plan development. > Prepare a prioritized list of nonindigenous plant species currently and potentially the greatest threats to natural areas. Suggest target areas and species for expanded control efforts. Start with the list prepared by the FLEPPC. Use information from the recommended survey and available monitoring results. Develop information on a plant community basis (i.e., pineland, hammock, beach, etc.). > Prepare a prioritized list of nonindigenous animal species currently and potentially the greatest threats to natural areas or native plant or animal populations. > Based on information from the above studies, generate brochures and news releases that describe the nonindigenous species problem in South Florida to land managers, decision makers, and the public. A public information effort based on scientific information will help develop a greater awareness of the problem and its present and potential impacts on natural areas. Once informed of their contributions to such problems, a concerned public often will change its habits. 45 NONINDIGENOUS SPECIES > Conduct horticultural investigations to develop sterile cultivars of popular and widely used, but invasive, non-native ornamental plants, such as certain flowering trees and Ficus species. (Suggested Lead--USDA) This technology is being used elsewhere for aesthetic reasons. For instance, fruitless mulberry trees, podless locust trees, and cottonless cottonwood trees are very popular nursery items in the southwestern United States. The Hong Kong orchid tree (Bauhiniavariegata), a popular ornamental plant in South Florida, is a local example. Species such as royal poinciana, Surinam cherry (Eugenia uniflora), the exotic Scaevola, and the many ornamental Ficus trees would be good candidates for this treatment. Development of sterile cultivars of non-natives with invasive tendencies could provide long-term benefits to natural areas. The FLEPPC list should be used to select non-native trees and shrubs whose propagation outside of cultivation should be controlled. > Encourage cultivation and use of native species in landscaping with special promotions to "introduce" promising native species to growers and the public. Over 100 tree species alone are native to South Florida, most growing nowhere else in the continental U.S. They are adapted to South Florida's soils and climate, and many are appropriate for landscaping. Greater use of native species in landscaping will reduce the probability of invasions by nonindigenous species. > Encourage the expansion into Southeast Florida of commercial operations that produce landscape mulch from melaleuca and other pest plants. At least two companies currently produce melaleuca mulch, but they do not appear to be operating on the East Coast of South Florida. > Encourage development and use of biological controls in place of pesticides to control pest species. Particularly with respect to large-scale, repeated applications, use of biological controls instead of pesticides has enormous potential to reduce damaging environmental impacts often associated with efforts to control exotics in managed areas such as agricultural fields, golf courses, and lawns. BIBLIOGRAPHY Bodle, M.J., A.P. Ferriter, and D.D. Thayer. 1994. The biology, distribution, and ecological consequences of Melaleuca quinquenervia in the Everglades. Pages 341-355 in S.M. Davis and J.C. Ogden, editors. Everglades: The Ecosystem and Its Restoration. St. Lucie Press, Daytona Beach, Florida. Center, T.D., J.H. Frank, and A. Dray Jr. 1994. The biological control of invasive non-indigenous species in Florida. Pages 209-214 in D.C. Schmitz and T.C. Brown, editors. An Assessment of Invasive Non-indigenous Species in Florida's Public Lands. Technical Report No. TSS-94-100. Bureau of Aquatic Plant Management, Division of Environmental Resources Permitting, FDEP, Tallahassee, Florida. Courtenay, W.R. Jr. 1994a. Non-indigenous fishes in Florida. Pages 57-63 in D.C. Schmitz and T.C. Brown, editors. An Assessment of Invasive Non-indigenous Species in Florida's Public Lands. Technical Report No. TSS-94100. Bureau of Aquatic Plant Management, Division of Environmental Resources Permitting, FDEP, Tallahassee, Florida. Courtenay, W.R. Jr. 1994b. Current major pathways of fish introductions. Pages 64-66 in D.C. Schmitz and T.C. Brown, editors. An Assessment of Invasive Non-indigenous Species in Florida's Public Lands. Technical Report No. TSS-94-100. Bureau of Aquatic Plant Management, Division of Environmental Resources Permitting, FDEP, Tallahassee, Florida. 46 NONINDIGENOUS SPECIES Doren, R.F., L.D. Whiteaker, G. Molnar, and D. Sylvia. 1990. Restoration of former wetlands within the Hole-in-theDonut in Everglades National Park. Proceedings of the Seventeenth Annual Conference on Wetlands Restoration and Creation. Hillsborough Community College, Plant City, Florida. Florida Exotic Pest Plant Council. 1995. Exotic Pest Plant Council's 1995 list of Florida's most invasive species. FLEPPC, West Palm Beach, Florida. Frank, J.H. 1994. Inoculative biological control of mole crickets. Pages 467-475 in A. Leslie, editor. Handbook of Integrated Pest Management for Turf and Ornamentals. CRC Press, Boca Raton, Florida. Frank, J.H., and E.D. McCoy. 1994. Invasive adventive insects and other organisms in Florida. Introduction to insect behavioral ecology: the good, the bad, and the beautiful: non-indigenous species in Florida. Florida Entomologist 78:1-5. Frank, J.H., and M.C. Thomas. 1994. Metamasius callizona (Chevrolat) (Coleoptera: Curculionidae), an immigrant pest, destroys bromeliads in Florida. The Canadian Entomologist 126:675-682. LaRoche, F.B., and A.P. Ferriter. 1992. The rate of expansion of melaleuca in South Florida. Journal of Aquatic Plant Management 30:62-65. Lorenz, J.J. 1993. Influence of hydrology on fish populations in the mangrove dominated zones of the C-111 and Taylor Slough basins and Biscayne Bay. Progress Report to Everglades National Park. NAS, Tavernier, Florida. McCann, J.A., L.N. Arkin, and J.D. Williams. 1995 Draft. Nonindigenous Aquatic and Selected Terrestrial Species of Florida: Status, Pathway, and Time of Introduction, Present Distribution, and Significant Ecological and Economic Effects. NBS, National Fisheries Research Center, Gainesville, Florida. Melaleuca Task Force. 1994. The Melaleuca Management Plan for Florida. Recommendations from the MTF. Second Edition, April 1994. Office of Technology Assessment. 1993. Harmful non-indigenous species in the United States. OTA-F-565. GPO, Washington, D.C. Robertson, W.B. Jr., and P.C. Frederick. 1994. The faunal chapters: contexts, synthesis, and departures. Pages 709737 in S.M. Davis and J.C. Ogden, editors. Everglades: The Ecosystem and Its Restoration. St. Lucie Press, Delray Beach, Florida. Schmitz, D.C., and T.C. Brown, editors. 1994. An assessment of invasive non-indigenous species in Florida's public lands. Technical Report No. TSS-94-100. Bureau of Aquatic Plant Management, Division of Environmental Resources Permitting, FDEP, Tallahassee, Florida. Schmitz, D.C., J.D. Schardt, A.J. Leslie, F.A. Dray Jr., J.A. Osborne, and B.V. Nelson. 1993. The ecological impact and management history of three invasive alien aquatic plant species in Florida. Pages 173-194 in B.N. McKnight, editor. Biological Pollution: The Control and Impact of Invasive Exotic Species. Proceedings of a Symposium, October 25 & 26, 1991. Indiana Academy of Science, Indianapolis, Indiana. Simberloff, D. 1994. Why is Florida being invaded? Pages 7-9 in D.C. Schmitz and T.C. Brown, editors. An Assessment of Invasive Non-indigenous Species in Florida's Public Lands. Technical Report No. TSS-94100. Bureau of Aquatic Plant Management, Division of Environmental Resources Permitting, FDEP, Tallahassee, Florida. South Florida Ecosystem Restoration Interagency Working Group. 1994. 1994 Annual Report. Available from ENP, Homestead, Florida. 47 NONINDIGENOUS SPECIES U.S. Army Corps of Engineers. 1995. Environmental assessment for an integrative approach to Melaleuca management in the State of Florida. COE, Jacksonville, Florida. Warren, M.L., and B.M. Burr. 1994. Status of freshwater fishes of the United States: overview of an imperiled fauna. Fisheries (Bethesda) 19(1):6-18. Woodall, S.L. 1980. Integrated methods for melaleuca control. Pages 135-140 in R.K. Geiger, compiler. Proceedings of Melaleuca Symposium, September 23-24, 1980. FDACS, FDOF, Tallahassee, Florida. Science Subgroup. 1996. South Florida Ecosystem Restoration: Scientific Information Needs. Report to the Working Group of the South Florida Ecosystem Restoration Task Force. 48