THE spot for spring Golden Eagles
Tussey Migration Data
Overview
Fall raptor migration along Pennsylvania's ridges has been documented for many years, starting at Hawk Mountain in 1934. Such autumn flights were known to occur on Tussey Mountain, with the former fire tower near Pennsylvania Furnace Rd about 5 miles southwest of our count spring site being a popular watch site (see Merrill Wood's classic Birds of Pennsylvania), as well as the Colerain Road near Spruce Creek. Part-time spring counts at Tussey were begun by PSU grad student David Brandes in March 1995 and continued through 2000 with the help of Dan Ombalski, Nick Bolgiano, Chuck Widmann and other local die-hards. Since then, full-time counts have been organized from late February through April. Over the years we have learned that Tussey is a unique spot for the spring golden eagle migration, consistently having the highest spring counts in the Appalachian region.
Here we summarize the count data, which can also be found at HawkCount
Flight Description
- The first three weeks of March is the peak time for golden eagles (see plot below), although the flight can be delayed by wintry weather (as in 2011 and 2017). Look in particular for warm southerly winds in early March, such as occurs ahead of approaching rain or snow. Good flights also can occur on northwest winds. Our long-term data do not show a statistically significant trend, suggesting that the eastern GOEA population is stable. However counts in recent years appear to have declined a bit.
- A large fraction of the eagles at Tussey are breeding-age, thus the early flight as compared to other hawkwatch sites in the northeast where many of the eagles passing are non-breeding juveniles (e.g., Braddock Bay and Derby Hill, NY). Other early raptor species include turkey vultures, red-tails, red-shoulders and rough-legs (like the one shown above).
- April is the best month for big numbers of raptors, although the flight is highly weather-dependent. Warm days with southerly winds and clouds are usually good, particularly after extended damp weather when the flights can be spectacular (e.g. 2001). Sunny days are usually not productive in April because thermal lift is so strong that hawks and eagles are moving at high altitudes and are thus are very difficult to spot.
- Common raptor species include turkey vultures, red-tails, broad-wings, sharp-shins, Coopers, ospreys, and kestrels. We usually see all 16 regularly-occurring species of eastern diurnal raptors each spring. Swainson's hawk has also been seen on 3 separate occasions.
Seasonal Records
Seasonal Records
Seasonal Records
- Osprey = 272 in 2001
- Bald Eagle = 91 in 2020
- Northen Harrier = 125 in 2001
- Sharp-shinned = 628 in 2001
- Cooper's = 172 in 2001
- N Goshawk = 6 in 2005
- Red-shouldered = 82 in 2005
- Broad-winged = 3599 in 2001
- Swainson's = 1 (multiple years)
- Red-tailed = 963 in 2001
- Rough-legged = 18 in 2005
- Golden Eagle = 239 in 2015
- Am Kestrel = 167 in 2001
- Merlin = 16 in 2001
- Peregrine = 5 in 2001
Daily Records
Seasonal Records
Seasonal Records
- Osprey = 83 on 4/27/17
- Bald Eagle = 53 on 4/29/20
- Northen Harrier = 46 on 4/08/01
- Sharp-shinned = 161 on 4/08/01
- Cooper's = 32 on 4/12/01
- N Goshawk = 2 on 3/12/05
- Red-shouldered = 24 on 3/14/14
- Broad-winged = 2173 on 4/12/01
- Swainson's = 1 (3 records)
- Red-tailed = 227 on 4/08/01
- Rough-legged = 4 (various dates)
- Golden Eagle = 62 on 3/03/08
- Am Kestrel = 42 on 4/08/01
- Merlin = 5 on 4/29/20
- Peregrine = 1 (many dates)
