This document summarizes information about barn owls, including their habitat, diet, breeding habits, lifespan, and predators. It also discusses water quality testing and the ideal levels of dissolved oxygen, nitrates, phosphates, and pH for a healthy stream ecosystem. The document concludes by noting that while high nitrate and phosphate levels can hurt aquatic life, these nutrients are important for plant growth in soil.

1. Riparian Zone Retreat and population studies Deanna Sapalio Honors Biology II Period 5

2. A male and female

3. Tyto Alba Barn Owl Barn owls can be found on every continent, except for Antarctica. They are the most widespread of all owl species. They can be found in many areas, including rural and urban habitats. Barn owls live in cavities. They can be found in hollow trees, cavities in riverbanks, barn lofts, hay stacks, caves, nest boxes, or even in church steeples.

4. Food Habits Owls depend on small mammals or rodents for food. They eat mice, voles, muskrats, hares, and rabbits. Barn owls hunt after sunset and rely on their hearing to catch their prey. Sometimes they will also eat small birds. Because of the barn owl’s size and strength, they have few predators. Occasionally, great horned owls, golden eagles, red kites, eagle owls, or hawks will prey upon the owls. Snakes and weasels will take the owl’s eggs.

5. Breeding Barn owls breed once a year. They breed any time of the year, depending on food supply. There can be from 2 to 9 eggs produced as a result of mating. Eggs hatch 29-34 days later After the eggs have hatched, the father steps up and collects food for his young. Time to independence: 3 to 5 weeks

6. The life of an Owl Most barn owls only live for one breeding season. The average life time for an owl is 20.9 months. They usually only survive through one breeding season and the mortality rate can be as high as 75%. Causes of death include: ~ the great horned owl and other predators. ~Cars, trains, fences, wires, and trucks also cause death. ~Starvation can also occur. When it is cold outside and small rodents are not available, they die. ~ Overpopulation does not affect the Barn Owl.

7. Food Chain Grass Insects Fish Muskrat Barn Owl Producer Autotroph Primary Consumer Omnivore Secondary Consumer Omnivore Omnivore Tertiary Consumer Carnivore

8. Food Web

9. Banding is the most common technique used to find the population size of barn owls.

10. Water Testing Data and Analysis The higher the dissolved oxygen level, the healthier the stream is. A dissolved oxygen level above 10 is good. A low level of nitrates and phosphates better for the stream. The pH level should be neutral, from 6.5-7.5. It is ideal to have a low amount of nitrates and phosphates. The ideal range is about 0-1. Plants will grow too rapidly and use all of the oxygen necessary for life if the nitrate and phosphate level is too high. Owls need water to survive, just like all organisms. The stream water would be best for the owls nutrition. If most of the organisms found in the stream were class three, the entire eco-system would die. The water would be polluted and would not be good for animals and plants to use. This would cut off vegetation for herbivores and omnivores and would finally kill all life.

11. Soil Testing and Analysis The pH level controls how well the plant utilizes the nutrients available. Nitrogen because it is essential to the proper functioning of plant metabolism. Phosphorus is also important because it is needed for blooming , helps the plant survive, and helps seed formation. Potash stimulates flowering and produces sugars during photosynthesis. If any of these are out of ideal range, vegetation will not grow and herbivores and omnivores will die. Unlike nitrate and phosphate levels in streams, the ideal ranges for these chemicals in the soil need to be high for the plants survival.

12. Positive and Negative Factors The healthy stream would be great for the barn owl. The water from the mine and marsh were too polluted for the owl’s survival. The low levels of nitrogen and phosphorus benefit all of the organisms that are sensitive to pollution. Many different factors have an impact on the riparian zone. The high level of nutrients are needed in the soil for plant life. The high levels of the different nutrients (nitrates, phosphates, and potassium) can be harmful in water ways. Other factors that affect life in the stream include temperature, turbidity, pH. A low amount of turbidity, a low temperature, and a neutral pH is best. The main causes of pollution in PA water ways are AMD and farmland runoff. In order to help the ecosystem, the amount of chemicals used in fields and lawns should be reduced. Polluted areas should be treated. Areas that are pollution free and are treated are great places for owls to get water.

13. Conclusion A high amount of nitrates and phosphates in streams can hurt the ecosystem greatly. However, these same nutrients are important for plant growth. I thought learning about the barn owls living habits and breeding techniques was very interesting. I love to listen to barn owls during the summer. An environmental topic I may consider researching in the future is AMD and its impact on the ecosystem.