Almost entirely fish. Typically feeds on fish 4-12′ long. Type of fish involved varies with region; concentrates on species common in each locale, such as flounder, smelt, mullet, bullhead, sucker, gizzard shad. Aside from fish, rarely eats small mammals, birds, or reptiles, perhaps mainly when fish are scarce.
What time of day do Ospreys exhibit the most activity?
An osprey on patrol abruptly folds its wings as it watches the waves in the river below. It falls and, a fraction of a second before impact, thrusts its legs forward. As far as British wildlife spectacles go, an osprey on the hunt is one of the most impressive, and July is the ideal time to witness one in action.
- When males, who do the most of the fishing, have chicks to feed in midsummer, this drama can be viewed at any time of day, however early morning and evening are often the finest times.
- They monitor a range of bodies of water, including estuaries, rivers, fish farms, reservoirs, and even tiny ponds.
- A hunting osprey often circles or hovers over the water for 10–40 meters before diving.
Success is contingent on a number of variables, including water quality and the weather; calm, cloudy days are excellent. Adults often capture a fish after two or three dives, although youngsters seldom do so until they embark on their first migration.
As a result, the majority of males remain at the nest location until all the young have gone. So, what adaptations make ospreys such accomplished fishers? Tim Mackrill, from the Rutland Osprey Project of the Leicestershire and Rutland Wildlife Trust, explains: 1 Super-keen eyesight A high concentration of receptors in their eyes provides ospreys with exceptional visual acuity, while a translucent ‘third eyelid,’ or nictitating membrane, closes when the bird strikes the surface for safety.
Ospreys can also correct for the refractive effect that causes fish to seem to be in a slightly different location under the water.
Materials for Nest Construction – Osprey nests are enormous and noticeable. A majority of an osprey nest consists of twigs and big sticks. Frequently, smaller bird species such as starlings or house sparrows inhabit the nest’s underbelly. The residents of Dunrovin refer to it as the basement flat.
Osprey nests may be up to five feet in diameter and two to seven feet thick. Moreover, osprey nests may weigh more than 300 pounds! The weight of a 300 pound osprey nest is comparable to nearly seven kindergartners! Ospreys like to return to the same nest year after year. Both the male and female osprey upgrade the nest with the most advanced materials upon arrival.
The lining of the nest is often constructed of softer material, such grasses or seaweed. Here at Dunrovin Ranch, Harriet and her partner typically utilize soft horse hair and hay in the core of their nest. In addition to natural materials, ospreys have been found to employ a range of man-made materials in their nests.
- People have reported spotting garbage bags, flip flops, netting, sod, and bailing rope in osprey nests.
- Baling twine can present a major hazard to both osprey adults and nestlings.
- Bailing string is highly harmful to ospreys since their talons are readily caught in the twine, ending in mortality.
- Numerous ranchers and farmers use bailing twine, making it accessible to ospreys.
At Dunrovin Ranch, we take great care to dispose of all baling twine appropriately. 
How many fish does an osprey consume on a daily basis?
What species of fish do Osprey consume? Different types of fish are consumed by Ospreys depending on the type of area in which they feed. Studies on the Osprey’s food have uncovered more than 80 types of fish across the species’ range. As a general rule, Ospreys consume the sort of fish that is most easily available to them, with just two or three types of fish dominating their diet in a given area.
- Throughout the season, Ospreys feeding in freshwater consume roughly the same species of fish.
- When feeding in estuaries and saltwater, Ospreys ingest a greater diversity of fish species.
- Because these environments are more sensitive to fluctuations in water clarity and fish availability because of fish migration, spawning seasons, or regular seasonal migrations, Ospreys must consume a wide variety of fish.
The table below illustrates that two to three species of fish make up the majority of an Osprey’s diet. At certain instances, like as in Paines Prairie, Florida, an Osprey’s diet consisted of only one kind of fish.
| Locality | Type and proportion of fish eaten by Ospreys |
| Eagle Lake, ne. Califormia | Tui chub (Gila bicolor) (48%); rainbow trout (Salmo gairdneri) (34), tahoe suckers (Catostomus tahoensis) (18%) |
| Cheppewa Nat’l. Forest, MN | Bluegills (Lepomis macrochirus) (35%); black crappie (31%); unidentified/other (34%) |
| Paynes Prairie, FL | Sunfishes (Centrarchidae) (95%) |
| Chesapeake Bay | Menhaden (Brevoortia tyrannus) (75%); unidentified/other (14%); white perch (Morone americana) (7%) |
| Creston, British Columbia | Tui chub (48%); rainbow trout (34%); tahoe suckers (18%) |