Habitat Analysis of the California Condor. Meagan Demeter GIS in Natural Resource Management APEC May, 2013

Transcription

1 Habitat Analysis of the California Condor Meagan Demeter GIS in Natural Resource Management APEC May,

2 Index Background...3 Literature Review...5 Hypothesis...6 Data...7 Methods...7 Anticipated Results...8 Policy Applications...9 Budget and Time Literature Cited

3 BACKGROUND The California condor is one of the oldest bird species in North America as well as the largest species of flying bird in the United States. Originally classified with the Andean Condor in the same genus, the California condor has been placed in its own monotypic genus of Gymnogyps. This is a result of the California condor's specific markings and scavenger diet of large mammalian carcasses such as deer, sheep, bears, and cougars. The California Condor has a wingspan of up to ten feet and a weight up to 30 pounds; making it the largest species of flying bird. The California condor is also the longest living species of bird with a lifespan of 60+ years. During the Pleistocene epoch, these Condors could be found distributed across the Americas as far as Florida. However, climate change during the last glacial period and the extinction of megafauna in the Pleistocene epoch led to a reduction of population and range 1. Five Hundred years ago the Condor's range spread from the West Coast to the Southwest including Arizona and Texas. Currently listed as Critically Endangered by the International Union for Conservations of Nature (IUCN), these Condors were on the brink of extinction only forty years ago. In the 1970s, a recovery plan to save the California condor was created. At that time, only twenty two California condor's existed in the wild. There are many reasons why the California condor's population has been in decline. Climate change and the extinction of their main source of megafauna during the Pleistocene epoch has limited the California Condor's natural habitat to only the West Coast specifically a small section of California and Arizona. These Condor's populations have also declined from urbanization and deforestation. Before the 1970s, the California condor populations were faced with man-made obstacles such as urban sprawl and increased development of their habitat. During the Gold Rush in 1848, miners would 1 "California Condor," California Condor, accessed May 16, 2013, 3

4 frequently steal Condor eggs and keep wild Condors as pets. This problem still persists today because many people continue to steal Condor eggs or kill wild Condors for recreation or to sell to museums 2. The issue of stealing Condor eggs is a particularly important issue because Condors reproduce during a short time span and Condor's typically have a small clutch size. Before Rachel Carson's Silent Spring was published in the 1960s, the majority of American citizens did not think or care about the environment or animal species. California Condor's that were necropsied before the 1970s were found with high levels of DDT and DDE in their systems; this lead to a major reduction in the Condor population. According to the Fish and Wildlife Service, eggshells collected and tested in the 1960s reported severe thinning and ultrastructural abnormalities in California condor eggshells collected in the late I960s by F. Sibley. They attributed the abnormalities to the probable effects of 1,1- dichloro,-2,2-bis(p-chlorophenyl)etylene (DDE), a breakdown metabolite of the pesticide 1,1,1- trichloro-2,2-bis(p-chloro-phenyl)ethane (DDT). DDT was banned for domestic use in the United States in 1972, and virtually all condor eggshell samples collected after 1975 have exhibited normal thickness (Snyder et al. ms). However, two eggs laid in 1986 by the last female California condor (Stud Book 12) to breed in the wild were very thin (44% thinner than the historical mean thickness) and contained inexplicably high levels of DDE and the parent compound, DDT (Kiff 1989). 3 In recent years, the California condor's most important causes of decline are shooting, manmade obstacles, and lead poisoning. The California condor, along with many other species of birds, are effected by urban sprawl and man-made obstacles. Many Condors are killed by becoming tangled in power lines and flying into buildings. The issue of lead poisoning is one of the most important when 2 "California Condor," California Condor, accessed May 16, 2013, 3 IBID 4

5 considering a plan to save the California condor. The Condor frequently eats carcasses of mammals that are killed by hunters that use lead shot when hunting; thus subjecting them to being poisoned by the lead. Suffering from years of decline, it was necessary to begin repopulation and to begin the process of finding a solution protect the California condor. The California condor is not only one of the oldest species of bird in the United States but it is also a valued species to Native Americans as well as American Citizens. Condors also provide an important ecological role because they consume carcasses of mammals that would otherwise decay; they are frequently referred to as natures clean-up crew. GIS would play an important role in protecting the California condor because suitable habitat could be found for effective catch and release programs. LITERATURE REVIEW The United States Fish and Wildlife Service have already begun the California Condor Recovery Plan in The California Condor Recovery Plan outlined five criteria that need to be achieved in order to save the Condor population. The Plan states that the five criteria are: These populations (1) must each number at least 150 individuals, (2) must each contain at least 15 breeding pairs and (3) be reproductively self-sustaining and have a positive rate of population growth. In addition, the non-captive populations (4) must be spatially disjunct and non-interacting, (5) must contain individuals descended from each of the fourteen founders. 4 The California Condor Recovery Plan does not believe that these goals can be accomplished in five years but it believes that much progress has been made through captive breeding and reducing threats to the Condor. A major goal of the California Condor Recovery Plan is to establish two 4 "U.S. Fish and Wildlife - Spotlight Species Action Plan," U.S. Fish and Wildlife - Spotlight Species Action Plan, last modified 2010, 5

6 geographically separate wild populations of Condor to diversify the genetic pool of the Condor. These populations are established through captive breeding programs. The California Condor Recovery Plan is partnered with the Zoological Society of San Diego, the Los Angeles Zoo, the Oregon Zoo, the World Center for Birds of Prey, and many wildlife agencies in Mexico. The breeding programs in these areas are extremely important because inbred fledglings are a major reason for the decline of the Condor's population. When starting breeding programs, Zoo's rely on the Stud Book to ensure genetic diversity. The Stud Book tracks males and breeding pairs to ensure that only the most genetically diverse pairs mate. Establishing geographically separate populations will ensure genetic diversity. Once released, the California Condor Recovery team has several steps to ensure the Condor survival. The steps include: monitoring free-flying Condors with the use of VHF telemetry, GPS transmitter data, and visual identifications, releasing California Condors in accordance with the release plans and established protocols, monitoring contaminant levels in California Condors, and provide contaminant-free carcasses at feeding sites within the historic range of California Condors and feeding site management at these locations, including the disposal of the remains of proffered carcasses. 5 HYPOTHESIS I believe that GIS would be a valuable asset in the plan to save and protect the California condor because suitable habitat can be found through GIS processes and data. GIS could target specific habitats that will be the safest and most beneficial for the Condor. My team would need to work with the California Condor Recovery Team in order track and research wild populations of California Condors. I would need to answer the following questions: What are the optimal habitat locations for the California condor? 5 "U.S. Fish and Wildlife," U.S. Fish and Wildlife - Spotlight Species Action Plan. 6

7 In what ways could the habitat locations be maximized to ensure the survival of 90% of the Condors born or released in the wild? How could GIS aid in tracking the Condor my GPS? DATA I will need to research the behavior and mating habits of the California condor. I will also need to collect data on the optimal habitat for the Condors. This means finding an area in California and Arizona suitable for raising fledglings and maintaining mating pairs. Much of the data already exists on the behavior and mating habits of the Condor which has been done by the California Condor Recovery Team and local zoologists. Some data will need to be collected in the field to determine what land can be set aside in Arizona and California or in other states. The land will need to as far away as possible from any developments, buildings, or power lines. The land will also need to be far removed from hunting grounds to prevent any poisoning from lead shot. GIS will aid in collecting data about the optimal habitat for the Condor because raster calculations can show the California Condor Recovery Team the habitat zones that are the most beneficial for releasing rehabilitated Condors. Data could also need to collect to find any suitable land that could be used for rehabilitating Condors to be released into the surrounding areas. METHODS Find the optimal areas for the Condor to be released and to reproduce in. GIS raster calculations and maps will be used to find these optimal areas. I will use the GIS raster calculator to find areas 7

8 suitable for the Condor. I will then create multiple raster layers in order to find the optimal sections of land that give the Condor the greatest chance of survival. These layers include a layer at least 400 meters from the nearest roadway and/or railway and within 100 meters of streams and water ways. An important layer would be habitat at least fifty miles from major cities and developments in order to protect the Condor from urbanization and power lines. Another important layer that will need to be created is habitat that is at least fifty miles from the nearest hunting grounds to prevent lead poisoning. These layers will also need to be within 100 meters of rock formations to maximize reproduction. The California condor typically nests in holes in different rock formations which makes finding suitable nesting habitats difficult. The Focal Statistics tool can be used to isolate ten pieces of land that satisfy these layers and maximize the protection of the Condor. I will also microchip each Condor with a GPS unit which will track and record the path of the released Condors. The data from the GPS units can be imported into GIS to acquire the best pieces of land for the Condor. GIS provides the strength of my proposal because GIS can provide specific analysis of the land needed to protect the Condor. GIS can find and target specific areas that are best suited for the Condor. The weakness lie in with the Condors natural reproductive habits which are difficult to find solutions for. ANTICIPATED RESULTS I anticipate that GIS will play a major role in finding the best habitat possible for the California condor. I believe that the Focal Statistics tool can isolate areas that are best suited for releasing the condor and establishing rehabilitation stations to raise fledglings to increase the population. Because Condors can have multiple clutches it is possible to hatch and raise a chick while the mating pair lay another egg. There are currently around five hundred Condors in the wild but I believe GIS can double 8

9 that population through proper allocation of suitable land. Also, tracking the Condor with GPS devices will allow zoologists and researchers such as me to follow released Condors in the wild. This information imported into GIS will allow researchers to ensure the wild condor's success as well as viewing what habitats the condors select to learn what ecological needs the Condors have. Researching the ecological needs of the released Condors will also aid in increasing the population of wild Condors. GPS tracking will also aid researchers during the reproductive months of the Condors which begin in winter and end in early spring. As previously stated, Condors have problems reproducing due to inbreeding, small clutch size, and lack of suitable nesting spots. GPS tracking and raster calculations would allow researchers to locate suitable nesting sites and find micro chipped Condors during mating season to ensure a chick hatches from the mated pair. POLICY APPLICATIONS There is currently a law in California that prohibits hunters to use lead shot while hunting in an effort to reduce the number of Condors killed by lead poisoning. However, this law is being challenged by local hunters because of the added cost of non-lead shot versus lead shot. They do not feel that preserving the Condor is as important as the cost and availability of ammunition. I believe that my proposal can change that opinion by demonstrating the ecological importance of the California condor as well as the Condors importance to the United States and United States history. Furthermore, GIS raster maps of specific areas of land being set aside for the Condor can demonstrate to local Californians and Arizonians that rehabilitating the Condor only requires a small percentage of land that will not affect hunting areas. My proposal may also be able to convince local governments to take more action to preserve the Condor. Local governments may also be more willing to allocate more land area designed to better 9

10 serve the ecological needs of the Condor. Educating the public about the California Condor is also important in preserving and protecting Condors. Research from my project can be used to educate the surrounding communities about ways they increase the populations of Condors such as not disturbing nests or protected areas for the Condors. BUDGET AND TIME Tasks and Supplies Costs Timeframe Wages $40,000 annual Salary N/A Computers $6, N/A (Laptop) Field Research $20, year (analyzing habitat, tracking Condors) Rehabilitation $20, year Programs (partnered with agencies and zoos) Data Analysis $10, Months 10

11 Land $10, Months Allocation Permits $4, Months GPS Units $ N/A GPS Tracking $1, Months Outreach $ Month Travel $500 plane ticket to California or Arizona N/A Total $100,000-$150, years 11

12 LITERATURE CITED Hooper Mountain National Wildlife Refuge Complexef. "California Condor Recovery Program." California Condor Recovery Program. Last modified December Accessed May 16, overy.html. National Geographic. "California Condor." California Condor. Accessed May 16, Recovery Plan for the California Condor. Last modified April Accessed May 16, Recovery%20Plan%20for%20the%20California%20Condor,%20April% pdf. U.S. Fish and Wildlife Service. "California Condor." California Condor. Accessed May 16, U.S. Fish and Wildlife Service. "California Condor." Species Profile. Last modified May 15, Accessed May 16, speciesprofile.action? spcode=b002. U.S. Fish and Wildlife. "Spotlight Species Action Plan." U.S. Fish and Wildlife Service- Spotlight Species Action Plan. Last modified Accessed May 16, Zoological Society of San Diego. "Animal Bytes: California Condor." Animal Bytes: California Condor.Last modified Accessed May 16,