RIPARIAN ZONE RETREAT Ashley Turcheck ; Period 4 – Biology I
Niche Great Horned Owl - Bubo virginianus
Can live from subarctic North America through parts of South America.
Prefers to make nests in deciduous or coniferous trees in woodland.
Secondary Consumer; Carnivore
Eats mostly medium-sized mammals, such as rabbits, raccoons, squirrels, mice, even cats. Insects, fish, and certain reptiles/amphibians are part of an occasional diet, too.
Also can prey on porcupines and skunks (due to a poor sense of smell).
Hunts primarily at night, perching at the top of trees and swoops down.
Niche – continued Great Horned Owl - Bubo virginianus
Typically choose mate by December.
Breed in January/February.
Usually do not build own nests; use old ones from other large birds and sometimes just add feathers.
Lay 1-5 eggs, though 5 is rare.
Young can be prey to foxes or coyotes; but as adults, they don’t have predators.
Move out onto branches, and fly after 6 weeks.
On average, young do not leave parents until they breed.
Owls’ coloring depend on their location.
Food Chain of the Great Horned Owl Producer Autotroph Primary Consumer Omnivore Secondary Consumer Carnivore Decomposer
Food Web of the Great Horned Owl Herbivore Producer Omnivore Carnivore Carnivore Producer Producer Carnivore Herbivore Herbivore Omnivore The Great Horned Owl is, for the most part, on the top of the food chain. So, it doesn’t have many predators. Being a carnivore, it eats things such as mice, raccoons, bugs, frogs, etc.
Stream Quality Data & Analysis
The stream quality, according to the organisms collected, is very good.
A majority of the organisms were pollution-intolerant; the stream quality is good.
Some of the organisms in the stream are eaten by some of the Great Horned Owl’s prey.
If something happened to these, the owl would be indirectly affected.
Water Testing Data & Analysis
A good ecosystem that has healthy water has:
Neutral pH level – around 8
Little or no nitrates/phosphates
Plenty of dissolved oxygen.
pH level should not be very much over/under 8 – making it basic or acidic
Nitrates and Phosphates can create overgrowth of vegetation.
Should be high levels of dissolved oxygen for organisms.
Animals that eat bugs/plants in the stream would be healthy; will be healthy for the Great Horned Owl to eat.
Good levels of bugs to eat.
Cold water holds more dissolved oxygen – allowing the organisms in the stream to survive.
Turbidity lets the organisms move around easily since it is easier to see (avoid predators; find prey).
Positive and Negative Factors
Stream quality was the ideal quality for the organisms.
Good amount of dissolved oxygen
Mine waters were not ideal.
Little dissolved oxygen
Marsh waters were not ideal, either.
Not a lot of dissolved oxygen
A lot of nitrates
A small amount of phosphate
Common sources of pollution:
High turbidity; acidic
Nitrates and phosphates
The riparian zone is very important to the environment. It includes many organisms, so if one of those begins to be negatively affected, everything else is affected in some way.
I found it interesting that everything is connected in the ecosystem.
I would like to find out more about AMD, and how it influences everything in the stream in a short and long period of time.
Pasquier, Roger F. "Owl." Encyclopedia Americana . 2010. Grolier Online. 13 May. 2010 <http://ea.grolier.com/article?id=0299380-00>.