Piping Plovers - An Endangered Beach Nesting Bird, and The Threat of Habitat Loss With. Predicted Sea Level Rise in Cape May County.

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1 Piping Plovers - An Endangered Beach Nesting Bird, and The Threat of Habitat Loss With Thomas Thorsen May 5 th, 2009 Predicted Sea Level Rise in Cape May County. Introduction and Background Piping Plovers are beach nesting bird that is having a great deal of trouble maintaining a sustainable population since the intensive development of the eastern shoreline last century. The remaining population is under an intensive management program with New Jersey Fish and Wildlife that is struggling to deal with the problems that a large tourism industry has presented them with. Beach front infrastructure, often directly adjacent to plover nesting sites, has left them with very little suitable habitat. Among other problems include elevated populations of egg and fledge predators supported by the food waste of shore communities, and overcrowded beaches inhibiting the foraging ability of the birds (Canale 2002). With predicted climate change and sea level rise, it is not known what will happen to the beaches and dunes of Cape May that plovers and many other plants and animals call habitat. As good stewards it is necessary to evaluate this situation to the best of our ability in order to show what can be done to protect biodiversity and not become a population sink for the species that use the barrier islands and mainland beaches of Cape May. Plovers were chosen in this study because they are intensely managed and there is a lot of data available for them in the area of focus. Breeding pairs on the New Jersey shore tend to have a 500 square meter territory where possible, which limits the amount of pairs capable of utilizing suitable habitat (Canale 2002). In the past, most communities have emphasized traditional methods of managing the shoreline, like anchoring the coast in place and beach replenishment. Today, scientists and coastal communities are realizing that these methods are unsustainable and do not work. This is

2 because the barrier islands of New Jersey have always been and always will be spatially dynamic, changing shape and size in relatively short timeframes (Nordstrom 1986, Psuty 2002, Psuty 2009). Objectives The goal of this analysis is to show how sea level rise is going to not only affect piping plovers, but every organism that utilizes the dune and beach habitat. It is meant to enhance place-based decision making for wildlife management and planning authorities. These organisms are adapted to a dynamic and unique ecosystem that humans are attempting to make static and homogenous, which leaves little room for a functioning ecosystem. It will also analyze the difference between habitats directly adjacent to infrastructure and areas that have back dunes and maritime forest or wetlands. Methods A GIS approach is taken to predict what plover habitat might look like in Cape May County with two different sea level rise scenarios, and a 5 year storm event combined with a sea level rise scenario (Figure 1). Since climatologists anticipate an increase in intensity and frequency of storm events with climate change, the future s one year storm may eventually become as intense as a five year storm. A LiDAR based digital elevation model, the most accurate and resolute remote sensing data available for the area of focus is used to show which areas will flood in these scenarios. Piping Plover nest coordinates were attained from New Jersey Fish and Wildlife Endangered Species Program, Beach Nesting Bird Division. Piping plover habitats in Cape May were digitized, with the following considerations: - Nesting piping plovers use about 500 square meters of habitat when possible (Canale 2002)

3 - Areas behind the foredune that are not developed with infrastructure are included because they will likely become the beach front with sea level rise. - Foraging habitat is included, from nest locations to present mean sea level. Once the plover habitat was spatially determined, the layer was overlaid with the three scenarios using the intersect tool in ARCMAP. This gave the area of inundated plover habitat, which was then divided by the total area of plover habitat to get a percentage lost due to sea level rise. Results The three lowest scenarios available for the year 2100 are displayed because the higher scenarios are too devastating for plovers to have a population. Sea level rise will become increasingly devastating to piping plovers and any other organism that depend on the beach as habitat. In developed areas, habitat will most likely be pinched off (figure 2) between the ocean and infrastructure. The sea level rise scenario often produced many tiny islands on the beach, which are not useful habitat for plovers. Most of the piping plover nests were in natural areas that are flat and low-lying, which is why a large percentage becomes inundated in the first sea level rise scenario (figure 1). It is these areas that are predicted to persist with sea level rise because they will accrete vertically and migrate inland figure 3). However, these areas are still likely to significantly lose area due to their change in shape and a negative sediment budget for the area (Psuty 2002). In developed areas, it is not yet determined how the county will manage sea level rise. Their decisions are critical to the conservation of beach and dune habitat. One option is to hold the line by making more shoreline stabilization features and taking on massive beach fill operations every few years. This is extremely expensive, unsustainable, and leaves poor habitat, if any for beach nesting birds (Nordstrom 1986, Psuty 2002, Psuty 2009). Another option is to stop repairing and rebuilding structures after they are

4 flooded and allow the developed barrier islands to migrate inland with their adjacent natural areas. This is a much more sustainable solution that would provide more natural habitat, but less likely to occur for several reasons. The digitization of plover nesting and feeding habitat polygons is less repeatable than the rest of the steps, because one could debate that piping plovers forage past the mean sea level line at low tides, and should be included as habitat. Also, undeveloped areas behind the foredunes may become developed over time. A negligible amount of areas below sea level that were not directly connected to the ocean or tidal waters were shown as inundated in plover habitat. The final and most important source of uncertainty is that it is impossible to predict exactly what the earth is going to be like in the future at based on computer models. It is proven that the climate is changing due to anthropogenic influences and that sea level rise is eminent, and the models were very professionally constructed. However, these are only estimates and the future is unpredictable. Summary and Conclusion Plover habitat is on the front line of sea level rise in any scenario. As the models indicate, plover habitats on developed beaches have nowhere to go. The best chance to preserve dune and beach habitat is to allow it migrate inland and accrete vertically. The Blue Acres program offers to buy properties in high risk areas of the shore to help Manage coastal hazards instead of using coastal stabilization practices (Psuty 2009). A good extension of this study would be to incorporate rates of erosion with different rates of sea level rise, because this study did not address that issue. It has been estimated that about 82% of New Jersey s coastline is critically eroding due to the loss of sediment due to longshore transport and diminishing sources of sand to replace it. This problem will be exacerbated by accelerated sea level rise due to climate change. This will lead to a loss of land

5 area, estimated in various case studies to inundate 1-3% of New Jersey s total land area (Psuty 2002). A model including these statistics might better predict what the beach habitat might look like in the future. Habitat Lost Due to Sea Level Rise Percent Lost m 1.2m 5 year storm and low sea level rise Scenario Figure 1. Percent habitat lost due to three sea level rise scenarios. The First scenario is based on mean sea level and the low end estimate for the year The second is the high end estimate based on mean sea level. The third scenario is a five year storm in addition to the first scenario, 0.6 meters.

6 Figure 2. Example of plover habitat that is likely to be impinged with sea level rise.

7 Figure 2. Example of plover habitat which may persist despite sea level rise.

8 Literature Cited Canale, S, Pover, T. BEACH NESTING BIRD PROTECTION IN NEW JERSEY. New Jersey Division of Fish and Wildlife, Endangered and Nongame Species Program Sections1-7. Cooper, M.J.P, M.D. Beever, and M. Oppenheimer Future sea level rise and the New Jersey coast: Assessing potential impacts and opportunities. Woodrow Wilson School of Public and International Affairs, Princeton University, NJ. 37p. Sea-Level-Rise-and-the-New-Jersey-Coast-Assessing-Potential-Impacts-and-Opportunities.pdf David R. Easterling, Gerald A. Meehl, Camille Parmesan, Stanley A. Changnon, Thomas R. Karl, 1 Linda O. Mearns. Climate Extremes: Observations, Modeling, and Impacts. Science 22 September 2000: Vol no. 5487, pp DOI: /science Psuty, N.P. and D.D. Ofiara Coastal Hazard Management, Lessons and Future Direction from New Jersey. Rutgers University Press, New Brunswick, NJ Psuty, N.P. Coastal Geomorphology Presentation. Rutgers University CRSSA. New Brunswick, New Jersey. February 2009.