Desert Food Webbing
You will work in a small group to draw the connections in the food web of a Sonoran Desert ecosystem. You may use the internet for the first part of this assignment, but make sure to document every source you use! After the group food web is complete, each student will complete an individual assignment. In‐Class Group Assignment 1.
Obtain a piece of poster board and a few colorful markers. 2.
Write the name of each organism in the list of organisms found in the Sonoran Desert Ecosystem, randomly, to cover, the entire piece of butcher paper (don’t write too big), and circle the name of each organism. 3.
Draw arrows to connect each organism to the organism(s) it eats and/or that eat it. Arrows must be drawn to show the direction of the flow of energy in the ecosystem. 4.
Write the name of each group member on the back of the food web. Individual Assignment 1.
Find and write out eight unique food chains from your team's food web (two of your food chains must have four trophic levels). Do not include decomposers in your food chains. 2.
Select two of your food chains, and identify the producer and three levels of consumers. 3.
Identify three organisms that are at the top of their food chains. 4.
Speculate about what would happen if all of the primary consumers in the ecosystem became extinct. 5.
Speculate about what would happen if all of the decomposers in the ecosystem became extinct. 6.
Predict what could happen if a non‐native beetle is introduced into the ecosystem and kills all of the native cactus in the area. 7.
Explain why food webs with many species are more resilient than those with few species. Selected Organisms found in the Sonoran Desert Ecosystem (food) [identity] ‰ Saguaro Cactus ‰ Mule Deer (grasses, shrubs, herbaceous plants) ‰ Bacteria [decomposer] ‰ Sanborn's Long‐nosed Bat (nectar) ‰ Mountain Lion (deer, rabbits, bighorn sheep) ‰ Pack Rats (cactus and other plants) [nest in cactus] ‰ Gambel’s Quail (seeds, green plants, cactus fruit) ‰ Black Bear (berries, fish, insects, small mammals, nuts, tubers) ‰ Red‐Tailed Hawk (rodents, snakes and lizards ) ‰ Desert Bighorn Sheep (grasses, herbaceous plants) ‰ Wild Buckwheat [herbaceous plant] ‰ Aphids (plants) ‰ Desert Shrew (insects, carrion) ‰ Tarantula Hawk Wasp (parasitic, tarantulas) ‰ California Leaf Nosed Bat (flying insects) ‰ Bobcat (small mammals, birds, reptiles) ‰ Beetles (cactus, insects) ‰ Desert Pocket Mice (seeds) ‰ Mosquito (plants, animal blood) ‰ Collard Lizard (insects, smaller reptiles) ‰ Coati (insects, lizards, carrion, rodents, nuts, fruit) ‰ Chipmunks (acorns, seeds, mushrooms, birds, insects) ‰ Coyote (mammals, birds, reptiles, foliage) ‰ Western Whiptail Lizards (insects, arachnids) ‰ Desert Lupine [herbaceous plant] ‰ Western Diamondback Rattlesnake (rodents, rabbits) ‰ Sonoran Desert Toad (insects, lizards, mice, toads) ‰ Creosote Bush ‰ Emory Oak [acorns] ‰ Mushroom [decomposer] ‰ Bull Grass ‰ Chuckwalla [lizard] (plants) ‰ Kit Fox (birds, reptiles, rodents) ‰ Great Horned Owl (insects, small mammals, birds) ‰ Gila Woodpecker (insects) [creates habitats for other species inside saguaros] ‰ Harris’ Hawk (rodents, rabbits, birds) ‰ Desert Cottontail Rabbit (grasses) ‰ Arizona Cottontop [grass] ‰ White Wing Dove (cactus fruit) ‰ Kangaroo Rat (seeds) ‰ Badger (insects larvae, bird eggs and nestlings) ‰ Mexican Grey Wolf (small animals, deer, plants, mountain lion cubs) ‰ Mesquite Trees ‰ California King Snake (rodents) ‰ Bracket Fungus [decomposer] ‰ Wolf Spider (insects) ‰ Cactus Wren (insects, spiders, lizards, seeds) ‰ House Gecko (insects) ‰ Desert Tarantula (insects, arachnids, small lizards and rodents ‰ Prickly Pear Cactus ‰ Acorn Woodpecker (acorns, insects) ‰ Prairie Dog (grasses) ‰ Elf Owl (insects, arachnids, shrews)