Great Horned Owl (Bubo virginianus)
Great Horned Owl (Bubo virginianus)
| Exposure Endpoint Type | Endpoint Value | Endpoint Description | Units | Sex | Life Cycle Stage | Sample Size | Location | Type |
|---|---|---|---|---|---|---|---|---|
| Time of Mating/ Laying | Feb 5-15 | peak period of egg laying | Female | Adult | 11-17 nests (3 study years) | southern Green County | Exposure Factor Datasets | |
| Fledging or Weaning Rate | mean number of fledglings produced per successful nest | fledglings/nest | Not Reported | Fledgling | 11-17 nests (3 study years) | southern Green County | Exposure Factor Datasets |
| Exposure Endpoint Type | Endpoint Value | Endpoint Description | Sex | Life Cycle Stage | Sample Size | Location | Type |
|---|---|---|---|---|---|---|---|
| Dietary Composition | meadow vole and jumping mouse (11.3%), juv. white-tailed jackrabbit (9.4%), horned or eared grebe (5.7%), American coot (22.6%), sora and Virginia rails (3.8%), duck (26.4%), sharp-tailed grouse (9.4%), blackbird (11.3%) | relative frequency of prey species occurence in nests | Not Reported | Nestling | 78 nest visits | Lostwood National Wildlife Refuge | Exposure Factor Datasets |
| Exposure Endpoint Type | Endpoint Value | Endpoint Description | Units | Sex | Life Cycle Stage | Sample Size | Location | Type | Lab |
|---|---|---|---|---|---|---|---|---|---|
| Body Weight - Mean | 914.2 (pallascens), 991.7 (pacificus), 1154.3 (occidentalis), 1317.8 (virgianus), 1238.6 (wapacuthu) | Body weight means for 5 subspecies | g | Male | Adult | 10-26 individuals/subspecies | Exposure Factor Datasets | Laboratory | |
| Body Weight - Mean | 1142.2 (pallascens), 1312.4 (pacificus), 1555.1 (occidentalis), 1768.5 (virgianus), 1556.0 (wapacuthu) | body weight means for 5 subspecies | g | Female | Adult | 12-29 individuals/subspecies | Exposure Factor Datasets | Laboratory |
| Exposure Endpoint Type | Endpoint Value | Endpoint Description | Units | Sex | Life Cycle Stage | Sample Size | Location | Type | Countries | Error |
|---|---|---|---|---|---|---|---|---|---|---|
| Home Range | 24.8-26.1 | mean home range size of nonterritorial individuals in 1990 and 1991 | square km | Both Male and Female | Adult | 6 (1990), 8 (1991) | Kluane Lake (60 deg57'N, 138deg12'W), Yukon | Exposure Factor Datasets | CANADA | |
| Territory Size | 4.83 | mean territory size of territorial pairs | square km | Both Male and Female | Adult | 16 territories | Kluane Lake (60 deg57'N, 138deg12'W), Yukon | Exposure Factor Datasets | CANADA | 0.40 SE |
| Exposure Endpoint Type | Endpoint Value | Endpoint Description | Sex | Life Cycle Stage | Sample Size | Location | Type | Countries |
|---|---|---|---|---|---|---|---|---|
| Dietary Composition | rodents (98.5%), birds + insects + reptiles + lagomorphs (1.5%) | percent of prey types in diet (seasonal average) | Not Reported | Adult | 522 pellets | near Bariloche, northwest. Patagonia | Exposure Factor Datasets | ARGENTINA |
| Exposure Endpoint Type | Endpoint Value | Endpoint Description | Units | Sex | Life Cycle Stage | Sample Size | Location | Type |
|---|---|---|---|---|---|---|---|---|
| Clutch or Litter Size | 1-4 | brood size at the time of banding | young/nest | Not Reported | Juvenile | 906 nests | near Cincinnati | Exposure Factor Datasets |
| Hatching Success | 47.3% | percent of nests with at least one young surviving to banding age (of all pairs observed) | Not Reported | Juvenile | 1777 territories | near Cincinnati | Exposure Factor Datasets |
