Owl pellets are the remains of an owl’s meal. In the owl pellet there are bone that were undigested, fur, feathers, and different types of rodents. Most owls swallow their prey whole which means they can’t digest bone that they eat so they have to ‘barf’ it up. The owl that we are studying is a Barn Owl. A barn owl is found in open grasslands and farmlands. Per season a barn owl lays about 5-11 eggs. An adult owl consumes several rodents each night. To put it into perspective a barn owl swallowing a rat is equivalent to a human swallowing a 15lb hamburger in one gulp. The size of each pellet depends on the species of the bird. About 20 hours after feeding an owl pellet is regurgitated. The purpose of this lab is to find the effects of owls …show more content…
in an ecosystem. The first hypothesis is a barn owl eats about two organisms a day. The second hypothesis is there will be lots of fur and bones in the owl pellet, perhaps an identifiable organism. Methods This lab is supposed to show how an owl fits into its ecosystem by what it eats.
It also extends the process of learning about food chains and food webs. The first step in this lab is that the pellet was described as small, brownish-gray, round, furry, and soft. The second step the pellet was placed in the tray and carefully it was taken apart. Our fingers were used to rub together the fur of the owl that was then used to find the pH level of the owl. Distilled water was poured on the fur. Then pH paper was placed in the distilled water and then compared to find the pH level. The owl pellet was then taken apart carefully and the bones found were placed in a separate dish. A picture was then taken of the remains. The amount of remains was then recorded in the chart below. The materials that were obtained for this lab were one owl pellet, answer sheets, dishes and trays, forceps and probes, ruler, white paper, and an owl pellet bone …show more content…
chart. Discussion In the course of the lab many tables were needed to complete the lab.
In Table 1 we found everything in our owl pellet except a vertebrate and a foot. The species represented in every bone that we found was a vole. In conclusion to our very first observations we found what the owl had ate. In Table there is more information in the chart. Overall in the class we found 8 rats, 8 voles, 7 mice, 2 shrews, 1 pocket gopher, and 4 birds and insects. To find the total biomass for each of the owl’s prey you had to take the total number in all samples (what the class total of each organism was) then multiply that by the prey biomass. An example for the rat would be 8x150, because the biomass is 150 grams and the total number that the class found was 8. To find the percent of diet you have to take the total biomass in one species and divide it by the overall total of all the biomasses. Another example for the rat would be 1200/1857 grams. The percent would then be 65% of the owls diet. The possible source of error in this lab could be if bones in the owl pellets are not identified correctly. In Image 1 and 3 it shows the bones that we found in our observations of the owl pellets. In Image 2 it shows the owl pellet before we opened it. At this stage we made our
observations. Analysis A barn owl consumes 2,900 grams of food each year (80*365). The 80 represents the two voles we found in our owl pellet and the 365 is the days in a year. An owl eats 12 mice per day, they then eat 372 mice per month (12*31). In two months a family of 6 owlets will eat 744 mice (372*2). An owl family will consume 6,800 grams of mice each year. The calculations to find what the parents are (80/25*365)*2=2336 grams and to find the owlets food per year (744*6=4464). Then the family consumes 6,800 grams of mice per year (2336+4464=6,800 grams). An owl could have been exposed to environmental pollution because a normal pH level is 7.6 for an owl and the owl pellet observed had a pH level of 5. Pollution led to a lower pH level which means it is more acidic. If grass has 10,000 calories of energy via photosynthesis and an owl is a tertiary consumer the owl will get 10 calories of the energy (10,000/1,000). If there was a trophic level above owls the organism that eats the owl will not get a lot of energy. That is why there is rarely any trophic levels above a owl in nature. The energy in a food chain comes originally from the sun. When a top consumer dies the corpse is left to decompose or for scavengers.
We observed Sowbugs in multiple environments to determine which environment they preferred. The observational chamber was a rectangle box split equally in half. One side of this rectangle was filled with dry sand that had been heated for five minutes by a lamp, and the other side was filled with damp soil that did not receive the lamp heat. We placed each sowbug on the middle boarder of the cool, damp soil and the hot, dry sand. We each chose one sowbug to track, and made a record of its placement each minute for five minutes total. We repeated this process three times. After each repetition, we removed the sowbugs, and replaced them with new sowbugs to observe. After this observation, we shared, and recorded our results. The sowbugs spent
In an article titled “Energy Digestibility of Giant Pandas on Bamboo-Only and on Supplemented Diets”, the goal of this study was to figure out the energy digestibility of bamboo by giant pandas using digestibility trials and through analysis using bomb calorimetry. An energy budget is a numerical statement that measures the amount of energy collected and the placement of the energy to various functions. Energy budgets can be described using the equation: E=M+P+U+F (where E is the total amount of energy consumed, M is the energy used for maintenance and activity, P is the energy used for production (which includes growth and reproduction), U is the energy lost in urine, and F is the energy lost in feces.). The total energy consumed minus the energy lost in feces is the digestible energy and shows the ability of the digestive system to process consumed food.
The Pacific Northwest is perhaps most commonly known for its awe-inspiring old growth forests that have been gracing the land for hundreds and hundreds of years. The land in British Colombia, Canada, Washington state, Oregon, and parts of Northern California are the only areas in the world where these forests exist. One of the most unique and amazing inhabitants of this age-old forest is the Northern Spotted Owl. The Northern Spotted Owl has been on the endangered species list for over ten years now. The Northern Spotted Owl can only be found in these old growth forests. The northern spotted owl requires many acres old forests to survive, due to its scarce food supply. They are very sensitive to their habitat, and simply cannot survive in any other environment. These owls, as well as the forests have been disappearing at an alarming rate due to the immense logging industry in its area.
The main similarity between minks and humans in the digestive system is that they both serv...
More reliable data can be obtained if more techniques are used to measure metabolic rate. By measuring the heat flow from an organism to its surroundings using a calorimeter, a more accurate metabolic rate can be measured (De V. Weir, 1949). The ratio of the quantity of food an animal consumes and the amount it excretes can also indicate the metabolic rate of that animal (Paradis et al., n.d.). Determining the water flux in animals with tritium labelled water is another valid method of measuring metabolic rates (Paradis et al., n.d.).
The Northern Spotted Owl can only live in old growth environment, it is considered an “indicator species”: The health of the Northern Spotted Owl population indicates the health of the old-growth forest ecosystem. An individual Northern Spotted Owl needs more than 3,000 acres of old growth to survive, because of its scarce food supply. The Northern Spotted Owl is found in the cool, moist woodlands on the Pacific Northwest. The habitat of the Northern Spotted Owl can be described as trees relatively large in diameter in the stand, multi-layered canopy, large tall live trees with cavities, broken tops, mistletoe, or platforms of branches capable of holding accumulated organic matter suitable for use as a nest, dead standing trees and fallen decayed trees to support abundant populations of prey species, especially northern flying squirrels and woodrats.
In conclusion, owls have shown they are excellent at adapting to any environment by the ability to fly silently to stalk prey. They use camouflaged and insulated feathers to hide and keep warm while hunting. Owl’s excellent binocular vision, and hearing helps to track prey from long distances. The only real risk of extinction of the burrowing owl is if people continue to kill off animals that dig holes for them. They have shown the ability to survive for a long time with the help of other animals digging holes for them. Owl’s will continue to evolve long after humans have
This type of writing is not meant for leisurely reading; it is meant to translate and share scientific findings amongst agriculturalists. Therefore, scientific writing is not always entertaining to read, sometimes, it can be difficult to understand and challenging to digest the material in its entirety. Even more so, articles, written academically, will possess visual literacy, mathematical literacy, data, and technical vocabulary; these variables will display the information in a different presentational form. In the article, Seasonal comparison of daily activity budgets of gray squirrels in an urban area, the authors choose to present the reader with tables, mathematical literacy, and charts representing the given data of the daily activity budgets of squirrels. Gonzales, Nilon, and Parker decided to use tables and graphs to help the reader better understand the written information with a visual representation of the data; sometimes it is easier to visually see data than to read
D. If these pellets had come from several roosts, would you expect to find the same kinds of skulls? Why or why not? What 3 factors would determine the types and numbers of skulls
A group of scientists from North Carolina and Oregon used medical technology to search an iron-stained concretion inside the specimen’s chest. With the assistance of imaging equipment and software, they were able to reconstruct 3-dimensional structures through the interior of the concretion. The images reveal a heart that was more like that of a bird or a mammal than those of reptiles, significantly adding to evidence suggesting that at least some dinosaurs had high metabolic rates. In addition, the heart appears to have been four chambered with a single aorta, which is most commonly found in mammals or birds.
If the number of animals recaptured in the second sample (n2) is less than 8, the estimation of the population is likely to be biased. If there are losses from the population during the remixing period, then the estimation would be for the size of the population at the time of the first sampling session. If there are gains in the population, the estimation would correspond to population size during the second sampling session.... ... middle of paper ...
http://animals.nationalgeographic.com/animals/amphibians/axolotl>. Clare, John. The. The "Food for Axolotls." Axolotls.
Zacherl, Danielle. “Biology 171 Evolution and Biodiversity.” National Association of Research in Science Teaching 2007 Annual Meeting, New Orleans LA. (2007):n. page. Print.
As previously mentioned, cannibalism is uncommon in many species. However, in the tiger salamander (A. tigrinum), it is a very common occurrence. Tiger salamanders have two life-history stages including a larval form and an adult form. During the larval stag...
Reptiles are vertebrate, or backboned animals constituting the class Reptilia and are characterized by a combination of features, none of which alone could separate all reptiles from all other animals.The characteristics of reptiles are numerous, therefore can not be explained in great detail in this report. In no special order, the characteristics of reptiles are: cold-bloodedness; the presence of lungs; direct development, without larval forms as in amphibians; a dry skin with scales but not feathers or hair; an amniote egg; internal fertilization; a three or four-chambered heart; two aortic arches (blood vessels) carrying blood from the heart to the body, unlike mammals and birds that only have one; a metanephric kidney; twelve pairs of cranial nerves; and skeletal features such as limbs with usually five clawed fingers or toes, at least two spinal bones associated with the pelvis, a single ball-and-socket connection at the head-neck joint instead of two, as in advanced amphibians and mammals, and an incomplete or complete partition along the roof of the mouth, separating the food and air passageways so that breathing can continue while food is being chewed. These and other traditional defining characteristics of reptiles have been subjected to considerable modification in recent times. The extinct flying reptiles, called pterosaurs or pterodactyls, are now thought to have been warm-blooded and covered with hair. Also, the dinosaurs are also now considered by many authorities to have been warm-blooded. The earliest known bird, archaeopteryx, is now regarded by many to have been a small dinosaur, despite its covering of feathers The extinct ancestors of the mammals, the therapsids, or mammallike reptiles, are also believed to have been warm-blooded and haired.