In our last article on Great Horned Owl facts we learned about its description, its habitat, its hunting skills and its dietary habits. However, we couldn’t cover other aspects like nesting, behavior, reproduction, conservation status etc. We will cover those aspects in this second part titled Great Horned Owl amazing facts. So, let us begin…
Great Horned Owl Amazing Facts: 1-5 | Nesting Habit
1. These amazing birds of prey are known for nesting on several types of trees such as pine, beech, juniper, cottonwood etc. During breeding seasons, the nests are known to deteriorate in condition and they are rarely used in later years.
2. Their usual habit is to adopt a nest that some other species had built and then discarded. They may however choose to nest in deserted building, dead snags, cavities in live trees, human-made platforms and even cliff ledges.
3. It is not unusual to see the Great Horned Owl nest on ground. They occasionally do that. It is a known fact that the pairs will first roost together close to the nesting site continuously for several months before the female eventually lays egg.
4. The size of the nest and the material used for making the nest can vary differently among the Great Horned Owls. This difference comes from the fact that the nests are usually built by some other species such as crows, ravens, squirrels, herons, red-tailed hawks, other hawk species etc.
5. Some Great Horned Owls may choose to line their nests with a variety of things like downy feathers that they pluck from their own breasts, leaves, bark shreds, trampled pellets, feathers or fur from the prey that they kill etc.
Great Horned Owl Amazing Facts: 6-10 | Reproduction
6. Great Horned Owls are monogamous by nature. They will mate with same partner year after year despite the fact that they are very solitary creatures. They will recognize their partners during the mating seasons through calls.
7. If one of the partners dies or is removed from its natural habitat, the one that is left behind needs to find a new partner. This might take several years to happen.
8. During the breeding season they will be start with calls and courtship. The courtship usually starts in October and ends in December and for those that need to find a partner, the choosing of the mate takes place between December and January.
9. During courtship, the males emphatically hoot and lean over. At the same time, they also puff up their white throats and resemble a ball. The display of the white throats work as a visual stimuli in low light conditions. Yes, the courtship takes place in low light conditions.
10. During courtship, the male is known for flying up and down a perch and approaches a potential mate. The male will then try to rub his bill against the potential female. If the female is receptive, she will hoot but will ensure that her hooting is subdued in comparison to the male.
Great Horned Owl Amazing Facts: 11-15 | Reproduction
11. The male may also try to convince a female by gifting her a freshly caught prey. The receptive female may then share the prey with the male.
12. It has been observed by scientists that during the breeding season, the males continue to hoot emphatically for up to 6 weeks towards the end of a year. The females will hoot but for a shorter period of time usually lasting no more than 10 days.
13. Being strictly monogamous, the same pair may continue to mate year after year and even for life except for scenarios of death or being removed from natural habitat.
14. The pair that have already mated once will usually go for a milder courtship only to rekindle their association and improve their bonding before they start reproducing. After the young owls are born and become independent, the pair will not usually stay together and maintain a solitary lifestyle.
15. It is the duty of the male to find a nest. The male will first find a nest and fly to it and then repeatedly stomp on it to get the attention of the female. They usually prefer large nests with open access rather than going for the ones that are enclosed by branches. This choice is pretty obvious because the Great Horned Owls are pretty big birds.
Great Horned Owl Facts: 16-20 | Reproduction & Newborns
16. The time when the eggs are laid by the female Great Horned Owls vary from region to region. For instance, the females will lay eggs anywhere between late November and early January in southern Florida. Those that live in the region Texas to Georgia will lay eggs between late December to early February.
17. Similarly, the egg laying months may be between early February to late March or late February to early April or early March to late April.
18. The usual clutch size is 2 eggs but the clutch size can vary between 1 and 6 eggs. The number of eggs laid will depend on the environmental conditions. The eggs have an average width of 1.83 inches and have an average length of 2.2 inches. The average weight of the eggs is 51 grams.
19. The Great Horned Owls have an incubation period of 33 days on average but it can range anywhere between 28 days and 37 days. Mostly females are responsible for incubation while the males are responsible for hunting and bringing food to females. The males deliver the first round of dinner typically after sunset (that is, as soon as it gets dark).
20. The average age of the newborns is 34.7 grams. During the first four weeks of their lives, the newborns gain weight at a rate of 33.3 grams a day on an average. By the time they reach 25 to 29 days old, the males will be around 800 grams and the females will be around 1,000 grams.
Great Horned Owl Facts: 21-25 | Newborns and Growing Up
21. The newborns, that is the nestling owls, develop in behavior anywhere between 2 weeks and 2 months after birth. Within this time, they learn to defend themselves. They learn to climb and to grasp food.
22. The young owls develop the ability of vocalization even before they hatch out of the eggs. When inside the egg, they will usually exert weak chirps. Shortly after hatching, they will develop a raspy chirp. As they keep growing, the character, pitch and intensity of their calls increase very rapidly.
23. The young owls manage to move out of the nest and get on to nearby branches by the time they are six weeks old. At around 7th week they develop the ability to fly. They usually do not become very competent in flying until they attain the age of 10 to 12 weeks.
24. The young ones will eventually leave the nest but the timing will depend on abundance of food. Once they leave their nests, they usually stay within 13.1 to 52 hectares from the nest. They stay within this range into the fall. By end of fall, they will disperse to several thousand hectares.
25. It has been observed that the young ones that leave their nests often beg for food from their parents up to 5 months after leaving the nest. Some young ones will not leave the territory of their parents completely until their parents start reproducing again. The young ones reach sexual maturity by the time they are 2 years old.
Great Horned Owl Amazing Facts: 26-30 | Behavior
26. Great Horned Owls are known for roosting in human-made structures, ledges, cavities, thick brush, snags and trees.
27. They are nocturnal. They will go out hunting during the night. However, when the food is scarce, they will go out hunting during the evening and continue to hunt till early morning. During the winter months when the food becomes really scarce, they will not shy away from hunting during broad daylight.
28. They are extremely ferocious when it comes to defending their territories and when it comes to protecting their eggs or young ones. They will also defend the young ones after they leave their nests.
29. When it comes to protecting their territories, eggs or young ones, they will clap their bills, scream, make guttural noises, hiss and then spread out their wings to warn. If the situation escalates, they will strike with their strong talons. They are also known to kill members of their own species.
30. They vocalize when its is dark after the sunset or during early morning. They make the very popular Hoo H’hoo sound.
Great Horned Owl Amazing Facts: 31-35 | Threats and Conservation Status
31. This bird is not known to have natural predators at least when they have grown into adults. However, the young ones may be hunted by Hawks.
32. It is a known fact that more than 50% of the young Great Horned Owls are hunted and eaten by hawks before they can reach adulthood.
33. Ravens, crows, other raptors, lynx, raccoons, coyotes and foxes may kill unattended nestling or even steal unattended eggs.
34. After from these, humans are a threat to these owls. Humans can simply kill these birds or accidentally poison them. It is not unusual that rats and rodents are often poisoned by humans. These poisoned rodents can become prey of these owls and the toxins in the bodies of their preys can spread in their bodies and kill them.
35. IUCN has listed the Great Horned Owls as ‘Least Concern’ for now. With around 5.3 million wild horned owls (including Magellanic species) in Americas, these birds are quite abundant.
This completes our list of Great Horned Owl Amazing facts. In case we have missed something here, feel free to let us know. However, we need to mention that we are not quite done yet. We will do one last article on Great Horned Owl random facts where you can learn some of the most amazing information about these majestic birds.