Incorporating the use of GIS into understanding amphibian ecology Christin McDonough-Haughey NRS509

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1 Incorporating the use of GIS into understanding amphibian ecology Christin McDonough-Haughey NRS509 As amphibian populations continue to decline, many biologists consider the loss of habitat and habitat fragmentation to be the most critical factor (demaynadier and Hunter 1998, Semlitsch 2000, Rothermel and Semlitsch 2002). Amphibian populations are especially prone to localized extinctions because they have complex life cycles that require ponds with specific hydroperiods for breeding, primarily forested habitats during migration, and a variety of upland habitats throughout the year (Semlitsch 2000). Available evidence suggests that pond-breeding amphibians have specialized habitat preferences during migration and in upland areas away from breeding ponds (Gibbs 1998, Rothermel and Semlitsch 2002). In addition, since amphibians are sensitive to stochastic events and undergo wide fluctuations in numbers, they are at further risk in combination with human induced factors. There is a recent increase in research focusing on the upland habitat requirements of amphibians, and the effects that habitat fragmentation has on their movements (Madison and Ferrand 1998, Allaye Chan-McLeod 2003). While seasonally flooded ponds are critical to the breeding cycle of spotted salamanders, adults only use these ponds during the breeding season (Dodd and Cade 1998). During most of the year, spotted salamanders reside in uplands surrounding seasonally flooded ponds. Most U.S. federal and state wetland regulations protect only the wetland itself; little or no protection is afforded to adjacent upland habitats (Semlitsch 1998). Biologically relevant life zones surrounding seasonally flooded pools are necessary for the protection of all pond-breeding amphibians. Previous research on spotted salamander emigration behavior has been used in a meta-analysis to estimate an appropriate life zone that might protect 95% of adults. Semlitsch (1998) estimated that the life zone for this species might extend up to 165 m into upland habitats. Windmiller (1996) reported that the integrity and characteristics of upland forested habitat within 300 -m were the most significant correlates of spotted salamander abundance. Semlitsch s concept of a life zone was applied to another study (Richter et. al 2001) where a buffer zone of 1000 m was recommended to protect a wetland complex. Thus, available evidence suggests that the maintenance of viable, or sustainable, amphibian populations requires the protection of significant areas of adjacent upland, non-breeding habitat (Windmiller 1996, Semlitsch 1998, Burne 2000). Recently amphibian populations have been declining worldwide due to habitat destruction, habitat loss, habitat fragmentation, and global climate change. These can all be quantified with the use of GIS. Since these animals have complex life cycles, amphibians sample multiple land cover uses, and GIS is a particularly useful tool in studying migratory patterns. The use of radio telemetry is an insightful tool (Madison 1998) and in combination with a GIS, can demonstrate the movement patters, spatial distribution, habitat selection, and corridor use of amphibians. Databases such as land use and land cover illustrate the types of habitats animals are using (Dodd and Cade 1998, Semlitsch 2000, Richter et. al 2001, Waters et. al 2001, Rothermel and Semlitsch 2002,). Edge habitat is also and important factor that greatly affects migration behavior of amphibians and is demonstrated in GIS (demaynadier and Hunter 1998, Gibbs 1998, Allaye Chan-McLoed 2003). Semlitsch (2000) discussed the use of a wetlands database in a GIS to show small wetlands and wetland complexes are critical to metapopulation dynamics. Ecological connectivity plays an important role in metapopulation dynamics. Amphibian dispersal among individual wetlands within a larger wetland complex is critical for the maintenance of amphibian populations. Therefore, it is necessary to identify small wetlands, and wetland complexes with the use of GIS. Loss of wetlands, and loss of upland habitat are both critical factors to sustaining amphibian populations. Therefore, it is also necessary to identify habitat fragmentation in the form of agriculture, roads, siviculture, or urban development. Inter-pond distances directly affect the probability of recolonization, and consequently, the chance of rescuing amphibian populations from extinction. Global climate change has been attributed to the accumulation of greenhouse gasses and the

2 reduction of the ozone layer. These are identified by the use of GIS to monitor the alteration of rainfall and temperatures, and increases in UV-B radiation (Semlitsch 2000). Since GIS is a relatively recent technology, it is becoming part of the science of ecology at a slower rate than I would like to see. Much of the literature I reviewed used measuring tape to quantify distances traveled by amphibians and used hand drawn maps to present their findings (Semlitsch 1980, Dodd 1998, Madison and Ferrand 1998). I think perhaps one of the reasons the use of GIS has been only slowly integrated into this field is because the software is constantly evolving; it is difficult to keep up! However, GIS is such a powerful tool that it will be impossible to present results without it in the very near future. Additional Literature Cited Burne, M. R Conservation of vernal pool-breeding amphibian communities: habitat and landscape associations with community richness. Thesis. University of Massachusetts, Amherst. demaynadier, P. G. and M. L. Hunter Effects of silviculture edges on the distribution and abundance of amphibians in Maine. Conservation Biology 12(2): Dodd, C. K. Jr., and B. S. Cade Movement patterns and the conservation of amphibians breeding in small, temporary wetlands. Conservation Biology 12(2): Madison, D. M. and L. Farrand III Habitat use during breeding and emigration in radioimplanted tiger salamanders, Ambystoma tigrinum. Copeia 2: Madison, D. M Habitat-contingent reproductive behaviour in radio-implanted salamanders: a model and test. Animal Behaviour 55: Rothermel, B. B., and R. D. Semlitsch An experimental investigation of landscape resistance of forest versus old-field habitats to emigrating juvenile amphibians. Conservation Biology 16(5): Semlitsch, R. D Biological delineation of terrestrial buffer zones for pond breeding salamanders. Conservation Biology 12: Windmiller, B. S The pond, the forest, and the city: spotted salamander ecology and conservation in a human-dominated landscape. Dissertation. Tufts University. Annotated Bibliography Allaye Chan-McLeod, A. C Factors affecting the permeability of clearcuts to redlegged frogs. Journal of Wildlife Management 67(4): The idea of habitat fragmentation as a major factor leading to amphibian declines has received growing attention. Here, the author addresses forest harvesting as a movement barrier to

3 amphibians from accessing seasonal habitats or juvenile dispersal to new breeding wetlands. The author collected UTM coordinates for each of the 130 red-legged frog locations using a Trimble GPS unit at least twice weekly. The author also applied real-time differential correction to base files to GPS positions to improve accuracy. The UTM coordinates of capture sites also were measured with a GPS unit to allow assessment of movement patterns relative to the home site, and physical features (such as forest interface, roads, streams, etc). In conclusion, clearcuts less than twelve years old were considered to be significant barriers to the frogs, but this was dependent on weather conditions and body mass. Gibbs, J. P Amphibian movements in response to forest edges, roads, and streambeds in southern New England. Journal of Wildlife Management 62(2): The author examined amphibian movements in relation to roads, forest edges, and streambeds in a tract of forest in southern Connecticut. Necessary for this study were GIS databases displaying landscape features such as the amphibian breeding pools, the forest patches, roads, open areas, and streambeds. In addition to examining amphibian response to edge habitat, the author also examined amphibian response to substrate conditions. In Connecticut there exists a very rich database of soil type, drainage classes, and substrate types. The study demonstrated that certain landscape features facilitate movement by amphibians, and hindered by others (particularly roads). Richter, S. C., Young, J. E., Seigal, R. A., and G. N. Johnson Postbreeding movements of the dark gopher frog, Rana sevosa goin and netting: implications for conservation and management. Journal of Herpetology 35(2): Radio telemetry was used to study post-breeding movements of dark gopher frogs from Transmitters were attached to frogs in a backpack fashion and individuals were located daily. Coordinates of the frogs final locations were determined with a Trimble GPS unit and migration distances were measured from those coordinates. All frogs were found within 300 m of the breeding pond. The authors used a GIS to illustrate land cover and habitat types such as a wetland complex containing three wetlands, adjacent upland forest, areas of clearcuts, and areas of prescribed burnings. Since it was determined that frog movements were affected by the clear-cut edge habitat, they recommended a 1000-m terrestrial buffer zone of undisturbed habitat surrounding the wetland complex be implemented in the future. This was illustrated with a USGA topological map containing the wetlands, land features, and the proposed area of protection around the wetlands. Scott, D. E., Metts, B. S., and J. W. Gibbons Seasonal wetlands and golf courses. Turfgrass and Environmental Research Online 1(4): 1-7. This study examined how amphibians use a variety of wetlands found on golf course landscapes, and compared them to amphibian use of seasonal wetlands not located on a golf course. Based on the results, recommendations were developed for enhancing biodiversity on golf courses by increasing the spatial distribution and abundance of seasonal wetlands as part of a golf course landscape. This type of study will encourage the use of a GIS and CAD in designing future golf courses. While this article is primarily a literature review, it does demonstrate the possibilities for future wetland conservation and GIS.

4 Semlitsch, R. D Terrestrial activity and summer home range of the mole salamander (Ambystoma talpoideum). Canadian Journal of Zoology 59: Semlitsch studied two populations of mole salamanders in South Carolina from He monitored their post breeding emigration behavior using radioisotope tagging. Individual animal locations were initially marked with flagging and were later plotted on maps. I threw this in not because of the impressive use of GIS, but because of the lack of it. Since this study was conducted over twenty years ago, GIS was not yet available. In order to determine home ranges, the area of the minimum polygon was determined by plotting to scale on graph paper an animal s locations during non-migratory periods. All the outer points of locations were connected by straight lines, the resultant polygon was then cut out of the graph paper, and the area was measured on a portable area meter to the nearest 0.01 cm 2. An activity center was identified by the concentration of points within a home range and its area was that of the minimum circle enclosing all points in a cluster. Now that would be easier with Arc! Semlitsch, R. D Principles for management of aquatic-breeding amphibians. Journal of Wildlife Management 64(3): This article discusses potential threats to amphibian populations and suggestions for managing sustainable populations. Ecological connectivity plays a very important role in metapopulation dynamics. Amphibian dispersal among individual wetlands within a larger wetland complex is critical for the maintenance of amphibian populations. Therefore, it is necessary to identify small wetlands, and wetland complexes with the use of GIS. Loss of wetlands, and loss of habitat are both critical factors to sustaining amphibian populations. Therefore, it is also necessary to identify habitat fragmentation in the form of agriculture, roads, siviculture, or urban development. It is critical to maintain a natural array of isolated wetlands connected by appropriate terrestrial habitats so that amphibian metapopulations can prosper. Inter-pond distances directly affect the probability of recolonization, and consequently, the chance of resuing amphibian populations from extinction. Recently amphibian populations have been declining worldwide due to habitat destruction, habitat loss, habitat fragmentation, and global climate change. These can all be quantified with the use of GIS. Since most amphibians depend on both aquatic and terrestrial habitats to complete their life cycle, both habitats must be carefully managed in order to maintain sustainable populations. Global climate change has been attributed to the accumulation of greenhouse gasses and the reduction of the ozone layer. These are identified by the use of GIS to monitor the alteration of rainfall and temperatures, and increases in UV-B radiation. Waters, J. R., Zabel, C. J., McKelvey, K. S., and H. H. Welsh, Jr Vegetation patterns and abundances of amphibians and small mammals along small streams in a northwestern California watershed. Northwest Science 75(1): The authors evaluated associations between stream size and patterns of occurrence and abundance of amphibians and small mammals within a watershed in northwestern California. GPS was used to accurately locate positions of stream sites. A GIS system was used to create a map with three layers of information: a contour coverage, a stream-channel layer created by a geographer based on contour crenulations, and the stream-site point locations. Watershed boundaries were then established around each stream site and drainage area could be obtained by calculating polygon area in ARC/Info (Environmental Systems Research Institute 1998). This article includes an impressive map illustrating the enormous Pilot Creek watershed, sample sites with the watershed, a locus map of California, and a stream layer including channels drawn by a geographer based on crenulations in contour lines from a 7 ½ - minute topographic map. Clearly a Geographic Information System was used to create the map, and analyze the data collected.

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