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David Scott, Brian Metts, and J. Whitfield Gibbons
Project Summary through December 2000
Although sampling is not completed, some trends are evident from our data. An overall comparison of amphibian species numbers on golf courses relative to off-course seasonal wetlands reveals that fewer species inhabit the golf course landscape (14 species vs. 21 at comparison wetlands). The difference between the two landscapes results largely from the paucity of seasonal wetland amphibian species on golf courses; whereas 14 seasonal wetland species were captured at off-course wetlands, only five were found on golf courses. A similar pattern emerges from the data collected only on golf courses when comparing courses with and without seasonal wetlands. Our data documented that most of the wetlands we sampled on golf courses harbored large populations of numerous fish species, and consequently these same wetlands contained very few amphibian species. A greater variety of amphibian species was found in both on-course and off-course seasonal wetlands, compared to permanent lakes and ponds. In summary, our sampling of golf courses thus far indicates that: 1) permanent wetlands are far more numerous than seasonal wetlands on courses, 2) the permanent wetlands on courses harbor large numbers of fish species, 3) amphibian species that use seasonal wetlands are generally absent from golf courses, and 4) courses that have seasonal wetlands have different amphibian species present than those courses with only permanent wetlands. As we continue to sample and add new courses, it is likely that these trends will continue. Project background: We have completed 18 months of this 3-yr study. Our objectives, as stated in the proposal and previous report, are:
Sampling Wetlands: Golf Course Participants: To date we have sampled five courses in the CSRA of South Carolina and Georgia. In addition to the courses identified in last year’s report (Houndslake Country Club, Cedar Creek Golf Club, North Augusta River Course, Jones Creek Country Club), we added Pine Ridge Country Club in Edgefield, SC. Pine Ridge has a variety of on-course wetland habitats, including one wooded seasonal wetland, a beaver pond, several large lakes, and a creek. Comparison Wetlands: The 12 comparison wetlands we sampled are located in Aiken and Barnwell Counties on the Savannah River Site (SRS) in South Carolina, and are generally within 30 miles of the golf courses we sample. The comparison wetlands cover a broad range of hydroperiod variation (i.e., very temporary ponds to nearly permanent) and landscape position (e.g., upland sandhills versus river floodplain). Ten of the comparison wetlands have a substantial herpetofaunal database from previous years of research. Sampling Methods: Sampling involves setting small (“minnow”) and large (“turtle”) hoop traps in all microhabitats of a wetland for four days/three nights. Captured animals are identified, and some are collected for species verification. When appropriate, each wetland is hand sampled using time-constrained dip-net sampling. Because different species breed in wetlands at different times, and also because animals are more trappable at some life stages than others, sampling at each wetland is conducted four times annually, beginning in December and continuing at approximate 2-mo intervals. Analyses: At the end of our study we will compare diversity and abundance data from permanent golf course wetlands to data from seasonal course wetlands. We will also contrast overall species diversity between comparison wetlands and golf course wetlands. Results from field surveys through September 1, 2000: Two of the golf courses (Houndslake and Cedar Creek) we are sampling have no seasonal wetlands (only permanent lakes or ponds); two courses (River Course and Pine Ridge) have a seasonal wetland in addition to permanent waters; one course (Jones Creek) has permanent ponds and a large creek, plus a single low-lying area that could be converted to a seasonal wetland with little effort. The permanent wetlands on all courses contain numerous predatory fish species. Lists of species from all courses are presented in Appendix 1. Although our sampling is not completed, some trends are evident from the data gathered thus far (Table 1). First, an overall comparison of amphibian species numbers on golf courses relative to off-course seasonal wetlands reveals that fewer species inhabit the golf course landscape (15 species vs. 21 at comparison wetlands; Table 1). The difference between the two landscapes results largely from the paucity of seasonal wetland amphibian species on golf courses; whereas 14 seasonal wetland species were captured at off-course wetlands, only six were found on golf courses.
Our sampling revealed eggs, larvae, and adults of these species, which likely indicate viable populations on both courses. Two of these salamander species were not found on the courses without seasonal wetlands. In addition, the River Course seasonal wetland produced numerous young narrow-mouthed toads (Gastrophryne carolinensis), a species that is only successful in very temporary fish-free ponds. The golf courses without seasonal wetlands generally had fewer amphibian species. Although two amphibian species typical of seasonal wetlands were captured at Houndslake (where we did not find any seasonal wetlands), the two species [the leopard frog (Rana utricularia) and the red-spotted newt (Notopthalmus viridescens)] were represented by a total of four individual adults. Eggs and larvae of these species were not found, and it is unlikely that populations are present and maintained by wetlands on the course. The single seasonal wetland species found at Jones Creek was the leopard frog. No adults were captured, but numerous egg masses were discovered in a low-lying depression after a heavy rainfall. It is likely that this small area could be converted to a true fish-free seasonal wetland with little effort. No seasonal wetland species were found at Cedar Creek, as there are no on-course seasonal wetlands; however, the creek and associated marsh habitats supported three species of salamanders: three-lined salamanders (Eurycea longicauda guttolineata), dwarf waterdogs (Necturus punctatus), and lesser sirens (Siren intermedia). The data illustrate that most of the wetlands we sampled on golf courses harbored large populations of numerous fish species, and consequently these same wetlands contained very few amphibian species. A greater variety of amphibian species was found in both on-course and off-course seasonal wetlands, compared to permanent lakes and ponds. Table 1—Summary of amphibian and fish species captures on golf courses and in off-course seasonal wetlands. Numbers in each cell are the total number of species located at each site for the respective categories and the total number of individuals (in parentheses). Letters in parentheses denote the type of wetlands found on the golf courses—P indicates that only “permanent” wetlands such as lakes, ponds, creeks, or marshes are present; S indicates that the course has a seasonal wetland in addition to the typical permanent wetlands. The off-course wetlands category is the combined data from 12 seasonal wetlands that vary in the length of time they hold water.
Implications of Results: Our sampling of golf courses thus far indicates that: 1) permanent wetlands are far more numerous than seasonal wetlands on courses, 2) the permanent wetlands on courses harbor large numbers of fish species, 3) amphibian species that use seasonal wetlands are generally absent from golf courses, and 4) courses that have seasonal wetlands have different amphibian species present than those courses with only permanent wetlands. As we continue to sample and add new courses, it is likely that these trends will continue. If the amphibian (and some reptile) species that use seasonal wetlands are missing from the golf course landscape, then our results indicate that this habitat type should be incorporated into course design. We believe that even slight modifications to “out of play” areas on courses might make a big difference to the variety of species that the golf course landscape supports. Because local courses appear to be very supportive of our efforts, we may be able to experiment with such modifications on a small scale to assess their effectiveness. We also believe that education will play a large role in the golf community’s acceptance of changes to course appearance. While it is true that seasonal wetlands do not look like permanent ponds and lakes, such wetlands are nonetheless aesthetically appealing. As the public is told of the value of such habitat to wildlife, these wetlands may be even more attractive. One result we expect is that, as people are informed of the value of seasonal wetlands, golfers will be pleased to have such habitats as part of their home course. |