Presentation on theme: "Bird Diversity and Habitat. Experimental Design Compare bird species in two habitats (U of A campus and Catalina Mountains) Do bird counts in these two."— Presentation transcript:
Experimental Design Compare bird species in two habitats (U of A campus and Catalina Mountains) Do bird counts in these two areas and record the findings Statistical analysis to compare bird diversity between the two habitats
Hypothesis Null Hypothesis: There is no significant difference in diversity between bird species in the Catalina Mountains and U of A campus Due to the birds’ habitat, we think that we will see more pigeons and sparrows on the University of Arizona campus, and more varieties of birds such as cactus wrens, mourning doves, and quails off campus near the Catalina Mountains. (Rejecting the null hypothesis)
U of A Campus Description The bird counts were taken at various places throughout the University Campus. Bird counts were taken at the Student Memorial Union, Arizona Sonora Dorm, Mall, Park Student Union, etc. Landscape varied from desert plants to grass areas
Catalina Mountain Description Counts were taken near a wash near the Catalina Mountains Desert landscape from low shrubs and brush to cacti and open terrain
Columba livia (Rock Dove and Common Pigeon) Habitat Wild rock doves nest in crevices along rocky seaside cliffs, close to agriculture or open shrub vegetation. In cities, the skyscrapers tend to take the place of their natural cliff surroundings. -Diet -They eat mainly seeds includes corn, oats, cherry, along with small amounts of knotweed, elm, poison ivy, and barley. -In cities, feral pigeons also eat popcorn, cake, peanuts, and bread
Campylorhynchus brunneicapillus (Cactus Wren) Habitat The Cactus Wren is common throughout the southwestern United States. This arid desert, dominated by cholla and other succulent cacti and spiny trees and shrubs, is characterized by high temperatures, low humidity, and scarce water. Diet The Cactus Wren primarily eats insects, including ants, beetles, grasshoppers, and wasps. Occasionally, it will take seeds and fruits. Almost all water is obtained from food, and free standing water is rarely used even when found
Callipepla gambelii (Gambel's Quail) Habitat Gambel's Quail live in warm deserts with brushy and thorny vegetation These birds also survive well in cultivated communities and prefer mesquite lined river valleys and drainages near these lands Common plants found in the quails' habitat include: desert hackberry, mesquites, little leaf sumac, desert thorns, catclaw acacia, scrub oak, and various other types of desert shrubbery Diet Ninety percent of the Gambel's Quail diet comes from plants. Various types of seeds and leaves are eaten throughout the year. During certain times of year fruits and berries from cacti are eaten. A few insects are eaten during the nesting season in spring and early summer.
Zenaida macroura (Mourning Dove) Habitat Mourning doves like farms, small towns, open wood, scrub, roadsides and grasslands. Diet Mourning doves eat a wide variety of seeds, waste grain, fruit and insects. Occasionally, they eat in trees and bushes when the ground foods have become scarce. Doves also like to ingest agricultural crops. Those especially coveted are cereal grains such as corn, millet, rye, barley, and oats. On rare occassions, doves can also be seen preying on grasshoppers, ants, beetles, and snails.
Passer domesticus (House Sparrow) Habitat House Sparrows like areas that have been modified by humans, including farms, residential, and urban areas. They are absent from uninhabited woodlands, deserts, forests, and grasslands. Diet House Sparrows forage on the ground, eating a variety of seeds and grains, sometimes obtained from livestock feed or livestock droppings. They also eat insects, spiders, and fruits in the summer.
Road Runner Habitat desert scrub, chaparral, arid open woodland, brush Diet consists mostly of animals (insects, reptiles, rodents, birds, etc.), but will occasionally eat fruit (mostly from cactus) and seeds.
Data Collected U of A Sparrow – 81 Pigeon – 19 Catalina Mountains Mourning Dove – 48 Sparrow – 12 Cactus Wren – 7 Quail – 27 Road Runner – 2 Pigeon – 4
Calculations: Using Inference on Proportions for Two Independent Samples Z-test State Hypothesis Ho : p1 = p2 Ha : p1 > p2 Find Test Statistic- Z x = number of species counted n = total birds counted in habitat Z = 1.95 Find P Value P = P(Z > z) P = P(Z > 1.95) = 0.0256 State Conclusion We reject our null hypothesis. We have reason to believe that more Mourning Doves habitat the Catalina Mountains versus the University of Arizona campus. This can be concluded since our P-Value is smaller than our significance level of 0.05.
Results from Z-test Bird SpeciesNull/Alternate Hypothesis Z ValueP ValueConclusion Mourning DoveH o : p 1 = p 2 H a : p 1 > p 2 1.950.0256Reject Null Hypothesis Cactus WrenH o : p 1 = p 2 H a : p 1 > p 2 2.690.00357Reject Null Hypothesis QuailH o : p 1 = p 2 H a : p 1 > p 2 5.590.00000Reject Null Hypothesis Road RunnerH o : p 1 = p 2 H a : p 1 > p 2 1.420.0777Fail to Reject Null Hypothesis SparrowH o : p 1 = p 2 H a : p 1 < p 2 -9.780.00000Reject Null Hypothesis PigeonH o : p 1 = p 2 H a : p 1 < p 2 -3.330.000443Reject Null Hypothesis
Calculations: Using Shannon Diversity Index *The Shannon Diversity Index is used to compare species diversity between study sites. Shannon Diversity Index equations used: H1= (nlogn- ∑ f1log f1) / n varH = (∑ f1log2 f1 –(∑ f1log f1)2 / n) / n2 t = H1 – H2 / (√ var H1 + var H2 ) *t – to determine if two values you obtain for the index are significantly different you can use the t-test df = (varH1 + var H2 )2 / ((varH1)2 / n1 + (var H2) 2 / n2 ) _________________________________ Sample Calculation for Pigeons: H1= (23log23- ∑ 19log 19) / 23 =.3054 varH1 = (∑19log2 19–(∑ 19log 19)2 / 23) / 232 =.0102 H2= (23log23- ∑ 4log 4) / 23 = 1.257 varH2 = (∑4log2 4–(∑ 4log 4)2 / 23) / 232 =.0022 t =.3054 – 1.257 / (√.0102 +.0022 ) = 8.55 df=(.0102 +.0022 )2/((.0102)2/19+(.0022) 2/4 )= 23.35 t > 2.8 therefore we reject the null hypothesis
Conclusion Due to our findings we must reject our null hypothesis. We have observed that a greater number of bird species can be found outside the city, Catalina’s, than within the city, UofA.
Conclusion Continued… Possible Error: More than one person observing sights. Counting same bird twice How could the experiment be improved? Focus on one species Choose more locations Longer observation periods and more days Tag Birds
Conclusion Our experiment has shown that humans have a definite impact on the habitation of birds. This information could help save bird, and other, species from human encroachment and stop developers from pushing housing farther into the Catalina’s.
Resources We used a couple websites including: http://birds.cornell.edu/birdhouse/speciesaccounts/HOUSPARO.HTM #Diet http://birds.cornell.edu/birdhouse/speciesaccounts/HOUSPARO.HTM #Diet http://wc.pima.edu/Bfiero/tucsonecology/animals/birds.htm http://animaldiversity.ummz.umich.edu/site/accounts/information/Colu mba_livia.html http://animaldiversity.ummz.umich.edu/site/accounts/information/Colu mba_livia.html http://natzoo.si.edu/Animals/Birds/Meet_the_zoos_birds/zoo_bird_info.cfm?bi rd=Greater%20roadrunner