The Python Problem GRADE LEVEL: 6-8 TIME ALLOTMENT: Four 45-minute class periods OVERVIEW: Using segments from the PBS series Nature episode, Invasion of the Giant Pythons, students will explore pythons and their impact on other species. In the Introductory Activity, students will learn about python digestion and unscramble photos illustrating a python’s digestion of prey. In the Learning Activity, students will learn how pythons have migrated to new environments and the dangers they pose to other species. Students will learn how invasive species, such as pythons, can threaten native species. In the Culminating Activity, students will learn about the Key Largo woodrat and ways scientists are trying to protect the species from pythons. Students will then explore a native species in their own region and create a presentation about the species, how it is being threatened, LEARNING OBJECTIVES: Students will be able to: ■Explain where pythons live and how they have moved from one environment to another. ■List python prey and discuss the process by which pythons capture and digest food. ■Describe dangers pythons pose to native species. ■Discuss efforts to rescue the Key Largo woodrat and the reasons why scientists are launching these efforts. ■Discuss one endangered or threatened local species and efforts being taken to help that species. Content Standard C: Life Science Fundamental concepts and principles that underlie this standard include: The Interdependence of Organisms • Organisms both cooperate and compete in ecosystems. The interrelationships and interdependencies of these organisms may generate ecosystems that are stable for hundreds or thousands of years. • Living organisms have the capacity to produce populations of infinite size, but environments and resources are finite. This fundamental tension has profound effects on the interactions between organisms. •Human beings live within the world’s ecosystems. Increasingly, humans modify ecosystems as a result of population growth, technology, and consumption. Human destruction of habitats through direct harvesting, pollution, atmospheric changes, and other factors is threatening current global stability, and if not addressed, ecosystems will MEDIA COMPONENTS from netbook or device Invasion of the Giant Pythons, selected segments Clip 1: Dinner Time An overview of how a python captures and digests its prey. Clip 2: It’s Raining Pythons A close look at how pythons have entered new environments Clip 3: Beware: Pythons A description of the dangers that pythons pose to other species. Clip 4: Saving the Rats A look at efforts to protect the Key Largo woodrat from pythons. Websites • US Fish and Wildlife Endangered Species Program http://www.fws.gov/endangered/ • This website includes a variety of information about endangered species. The “Species Search” page (http://www.fws.gov/endangered/species/) used in the Culminating Activity, features a US map where visitors can locate endangered plant and animal species throughout the country. Websites Cont’ Optional (for research in Culminating Activity): The Comprehensive Everglades Restoration Plan http://www.evergladesplan.org/index.aspx This website includes a variety of information about the Everglades, including facts about plants and animals: http://www.evergladesplan.org/facts_info/sy Websites Cont’ California Department of Fish and Game/ Invasive Species Program http://www.dfg.ca.gov/invasives/. This website contains information about invasive species in California and efforts being taken to reduce their negative effects on native species and environments. South Florida Natural Resources Center/ Everglades National Park: Natural Resources Management/ Burmese Pythons http://www.nps.gov/ever/naturescience/upload/PythonFa ctSheetHiRes.pdf. This fact sheet provides detailed information about Burmese pythons and efforts underway to monitor and control the python population. Directions: • Click audio to start. What do you know about pythons? Are they venomous? What rate do pythons move from one place to another? What prey do pythons eat? Procedure on how to reply to blog: 1. Go to Mrs. LaRue’s blog http://kangerooscience.blogspot.com/ 2. Sign into Google with your user name/password 3. Click on your hour and start your blog with your last name and reply to questions on slide 8. 4. Complete this assignment by tomorrow, Wednesday, 5-9-12. Burmese Python Python molurus bivittatus Where do Burmese Pythons live? Native to the jungles and grassy marshes of Southeast Asia, Burmese pythons are among the largest snakes on Earth. They are capable of reaching 23 feet (7 meters) or more in length and weighing up to 200 pounds (90 kilograms) with a girth as big as a telephone pole. Where do Burmese Pythons Live? How do they kill their prey? They kill by constriction, grasping a victim with their sharp teeth, coiling their bodies around the animal, and squeezing until it suffocates. They have stretchy ligaments in their jaws that allow them to swallow all Behavior of Burmese Pythons When young, they will spend much of their time in the trees. However, as they mature and their size and weight make tree climbing unwieldy, they transition to mainly grounddwelling. They are also excellent swimmers, and can stay submerged for up to 30 minutes before surfacing for air. Reproduction Burmese pythons are solitary animals and are generally only seen together during spring mating. Females lay clutches of up to 100 eggs, which they incubate for two to three months. To keep their eggs warm, they continually contract, or shiver, their muscles. Answer the following question on paper before class tomorrow: 1. Explain how the pythons get to Florida? 2. Infer how the invasion of the pythons will impact the native species of Florida? 3. What are 3 threats that pythons pose on native species in Florida? Present Day By year 2100 Burmese pythons are carnivores, surviving primarily on small mammals and birds. They have poor eyesight, and stalk prey using chemical receptors in their tongues and heatsensors along the jaws. What do we eat? Key Largo Woodrat (Neotoma floridana smalli) Federal Status: Endangered (August 31, 1984) What is a Key Largo Woodrat? The color of the Key Largo woodrat is described as sepia or grey-brown above shading into cinnamon on the sides, with cream or white ventral coloration. The forefeet are white to the wrist and the hindfeet are primarily white to the ankles. The Key Largo woodrat has large ears, protuberant eyes, and a hairy tail. The head-and-body-length of the Key Largo woodrat ranges from 120 to 230 mm, their tail length ranges from 130 to 190 mm, and their hindfoot length ranges from Where they live Habitat The Key Largo woodrat is a resident of tropical hardwood hammocks, the climax vegetation of upland areas in the Keys. Hammocks provide a shady, humid microclimate with less wind and temperature variation than more exposed habitats. The soils are poorly developed, typically consisting of shallow humus and litter overlying the limestone substrate, but may become deep in some forested areas. Reproduction The Key Largo woodrat is capable of reproducing all year, although seasonal peaks in winter are evident (Hersh 1981). Key Largo woodrat litter sizes range from one to four young, with two most common. Female woodrats can produce two litters a year (Brown 1978b). Sex ratio favors 1.2 : 1 male to female (Hersh 1981). Both sexes require about 5 months to reach sexual maturity (Hersh 1981). The life expectancy of the Key Largo woodrat is unknown, but is probably similar to other subspecies of Neotoma floridana, which may live for 3 years but probably average less than 1 year (Fitch and Guess what we Eat? Key Largo woodrats are nocturnal omnivores, but feed primarily on a variety of leaves, buds, seeds, and fruits (Brown 1978b) Answer the following questions before class tomorrow: • 1. Explain 3 different ways that we can protect the Key Largo Woodrat. 2. Infer why it is important to save the Key Largo Woodrat from extinction. Answer the following questions before class tomorrow: • Please go to the following website http://www.fws.gov/endangered/species/ Click on the state of Florida and answer the following question: Explain 3 organisms that could be prey items on the ENDANGERED list in Florida. Bibliography http://www.fws.gov/verobeach/MSRPPDFs/ KeyLargoWoodrat.pdf http://animals.nationalgeographic.com/anim als/reptiles/burmese-python