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The Florida Institute of Phosphate Research was created in 1978 by the Florida Legislature (Chapter 378.101, Florida Statutes) and empowered to conduct research supportive to the responsible development of the state’s phosphate resources. The Institute has targeted areas of research responsibility. These are: reclamation alternatives in mining and processing, including wetlands reclamation phosphoaysum storage areas and phosphatic clay containment areas; methods for more efficient, economical and environmentally balanced phosphate recovery and processing; disposal and utilization of phosphatic clay; and environmental effects involving the health and welfare of the people, including those effects related to radiation and water consumption. FIPR is located in Polk County, in the heart of the central Florida phosphate district. The Institute seeks to serve as an inffrmation center on phosphate-related topics and welcomes information requests made in person, or by mail, email, or telephone. Executive Director Paul R. Clifford Research Directors 6. Michael Lloyd, Jr. -Chemical Processing J. Patrick Zhang -Mining & Beneficiation Steven G. Richardson -Reclamation Brian K. Bit@ -Public Health Publications Editor Karen J. Stewart Florida Institute of Phosphate Research 1855 West Main Street Bartow, Florida 33830 (863) 534-7160 Fax: (863) 534-7165 http://www.fipr.state.fl.us HABITAT FACTORS INFLUENCING THE DISTRIBUTION OF SMALL VERTEBRATES ON UNMINED AND PHOSPHATE-MINED FLATLANDS IN CENTRAL FLORIDA FINAL REPORT Henry R. Mushinsky and Earl D. McCoy with Robert A. Kluson Postdoctoral Fellow DEPARTMENT OF BIOLOGY AND CENTER FOR URBAN ECOLOGY UNIVERSITY OF SOUTH FLORIDA TAMPA, FLORIDA 33620-5150 Prepared for FLORIDA INSTITUTE OF PHOSPHATE RESEARCH 1855 West Main Street Bartow, Florida 33830-7718 Contract Manager: Steven G. Richardson FIPR Project Number 95-03-115 August 2001 DISCLAIMER The contents of this report are reproduced herein as received from the contractor. The report may have been edited as to format in conformance with the FIPR Style Manual. The opinions, findings and conclusions expressed herein are not necessarily those of the Florida Institute of Phosphate Research, nor does mention of company names or products constitute endorsement by the Florida Institute of Phosphate Research. PERSPECTIVE FIPR’s purpose in funding the research was to gain information to guide wildlife habitat rehabilitation efforts on phosphate mined lands in central Florida. The general objectives of the study were to compare small vertebrate wildlife species distributions and habitat characteristics on unmined natural habitats and reclaimed mine sites; to correlate wildlife species presence with various habitat characteristics; and to identify possible ways to improve habitat restoration on mined lands. A previous study (FIPR Publication No. 03-100-129, “Habitat Factors Influencing the Distribution of Small Vertebrates on Unmined and Phosphate-Mined Uplands in Central Florida”) emphasized xeric (drier, well-drained) habitats, while this study deals with mesic (intermediate moisture between xeric and wetland) habitats. Wetland habitats were not studied. Small vertebrate species were trapped (e.g., mice, lizards, and toads) or observed (birds) on unmined natural habitats and on several reclaimed mine sites. Most of the mined sites had not been specifically reclaimed to mimic natural habitats, but they were thought to provide some wildlife habitat values and would provide a range of habitat characteristics that could possibly be correlated with the presence or absence of various wildlife species. The study emphasized vertebrate species that were relatively common in unmined native habitats but were absent or underrepresented at reclaimed sites. Because the study “focused” on species that were underrepresented at reclaimed sites relative to “reference” (unmined, natural) sites, they were thus called “focal” species. A better understanding of the biology of these focal species may contribute to increasing their abundance on reclaimed sites in the future. The intent and hope was to identify habitat characteristics important to these species that could be recreated on reclaimed mined lands. While the study did identify relationships between various habitat characteristics and focal species, it was not always clear whether or not the underrepresentation of a species was because of unsatisfactory habitat or because the species had not yet reached the site. The subjects of site isolation, colonization, and habitat quality are being addressed for a few selected vertebrate species in FIPR Project 98-03-133, “Habitat Characteristics of Key Vertebrate Species that Are Under-Represented on Phosphate Mined Lands.” It is quite possible that in addition to improving reclamation practices to provide the necessary habitat characteristics, we may need to reintroduce some species back to the reclaimed sites, as has been done with gopher tortoises (see Macdonald 1996 and Small and Macdonald 2001). Time is also an important factor that affects both vegetation development and colonization. Another important point is that because some species were absent or underrepresented does not mean there were no vertebrate species on reclaimed lands. The references listed below indicate that a wide variety of wildlife utilize mined lands. Reclaimed lands tend to be more open – have lower density and cover of woody vegetation – than the unmined natural sites studied by Mushinsky and McCoy. Thus a few wildlife species that are better adapted to open habitats were actually more abundant iii on reclaimed lands than unmined lands. Conversely, as the study emphasized, the unmined sites tended to have greater woody vegetation cover with more complex structure, which favored the “focal” species. To reiterate, the purpose of this study was to gain insight into how to get more of the focal species on reclaimed lands. Edelson, N.A. and M.W. Collopy. 1990. Foraging ecology of wading birds using an altered landscape in central Florida. FIPR Publication No. 04-039-087. Kale, H.W. and P.C.H. Pritchard. 1997. Wildlife, p. 7-1 to 7-76. In: Evaluation of constructed wetlands on phosphate mined lands in Florida. FIPR Publication No. 03- 103-139. Kiefer, J.K. 2000. Vertebrate utilization of reclaimed habitat on phosphate mined lands in Florida: research synopsis and habitat design recommendations, p. 397-411. In: W.L. Daniels and S.G. Richardson (eds.). Proceedings of the 17th Annual Meeting of the American Society for Surface Mining and Reclamation, Tampa, Florida, June 11-15, 2000. ASSMR, 3134 Montavesta Rd., Lexington, KY. Macdonald, L.A. 1996. Reintroduction of gopher tortoises (Gopherus polyphemus) to reclaimed phosphate land. FIPR Publication No. 03-105-126. Small, C.R. and L.A. Macdonald. 2001. Reproduction and growth in relocated and resident gopher tortoises (Gopherus polyphemus) on reclaimed phosphate-mined lands. FIPR Publication No. 03-105-145. Streever, W.J. and T.L. Crisman. 1993. A comparison of fish populations from natural and constructed freshwater marshes in central Florida. J. Freshwater Ecology 8 (2): 149- 153. Steven G. Richardson FIPR Director of Reclamation Research iv ABSTRACT We used “representativeness” as a means of comparing vertebrate wildlife species found on reclaimed phosphate mined land with vertebrate wildlife species found on unmined land in central Florida. Land properly reclaimed as wildlife habitat should support a flora and fauna that “represents” the native flora and fauna that existed prior to the mining. We identified the pool of resident species on unmined mesic flatlands (reference sites) for comparison with the species living on mined (reclaimed) lands. Those vertebrate species that are under-represented at reclaimed sites relative to their distributions and abundances at reference sites are identified as “focal species." Soil characteristics and vegetation profiles were measured at each of the sixty study sites used for the vertebrate wildlife comparisons. Many soil and vegetation differences exist between the reclaimed and reference sites. The vegetation structure at reclaimed sites was different than the reference sites. All reclaimed sites lacked a Middle-Canopy layer, and were dominated by a few foliage layers. The resident species include 12 amphibian species, 17 reptile species, 6 mammal species, and 46 bird species. Twelve species including 1 amphibian, 2 lizard/turtle, 0 snakes, 0 mammals, and 9 birds are focal species; that is, these twelve species are found much more commonly at reference sites than reclaimed sites. Four bird species were found more frequently at reclaimed sites than at reference sites. We found that preferences for breeding sites (amphibians) or for vegetation structures (reptiles and mammals) could distinguish most of the focal species from the non-focal species. We found that vegetation structure alone could distinguish nearly all focal from non-focal bird resident species. The focal species all prefer wooded areas, some favoring areas with extensive tree canopy and others favoring areas with shrubs or low canopy, while the non-focal resident species almost all prefer open areas that are conducive to ground foraging. We conclude that proper reclamation of mesic habitats will have to account for the high variation of species composition at a given site and incorporate a high degree of habitat heterogeneity. We suggest that existing patches of reclaimed mesic habitats are isolated from existing remnants of reference habitats