Bird-lovers documenting raptors passing over the Jenner Headlands have established the coastal route as a key migratory flyway, reaffirming the area's importance as a natural preserve.

That was the word Thursday from the Sonoma Coast, where conservationists are conducting a fall migration count for the second consecutive year and are coming up delighted.

"It's a gold mine," said Larry Broderick, a naturalist and interpretive specialist who is leading the effort. "We all kind of knew it was here. We just couldn't get access."

The 5,630-acre headlands property has been in private hands for more than 100 years but two years ago was purchased by the Sonoma Land Trust and the Sonoma County Agricultural Preservation and Open Space District. It will be managed by The Wildlands Conservancy.

Birders who used to catch fleeting glimpses of raptors flying over the headlands from Highway 1 now have the chance to document the raptors from an elevated knoll with a 360-degree view of the flyway, Broderick said.

And what last year was a small volunteer effort over a total of six days involves twice the people and more expertise for what will be 12 or 18 days of observations this year, he said.

"You've got a commanding view of everything — a 360 view — most predominantly a view to the north," Broderick said. "We have an unparalleled view for miles, basically."

A variety of raptors have been seen passing through en route to points south — Red-tailed Hawks, Sharp-shinned Hawks, Coopers Hawks, Northern Harriers and kestrels, among others — as well as few rarer birds like a Peregrine Falcon, a golden eagle and some merlins.

In addition, bird counters have determined that large numbers of Ferruginous Hawks, whose breeding and overwintering habitats have been in jeopardy, are finding their way to Jenner and the Russian River area to spend the colder months.

The coastal prairie grasslands on the headlands provide rich feeding grounds and habitat similar to the prairie lands farther north which have diminished significantly due to coastal development, avian expert Dave Barry said.

"It's a wide open expanse," Broderick said. "It's perfect for hunting. And above and beyond that, for birds that migrate, it's a straight shot. They've got the wind coming up from the coast, the thermals, three or four different wind patterns that basically funnel the birds right over us."

Jenner bird counters are using the same tools and system utilized for the annual raptor count at Hawk Hill on the Marin Headlands, where some 300 raptors an hour pass on their migratory routes.

The counts are smaller in Jenner, closer to 90 per hour for the past two years, but more years and more counts are needed to consider the numbers firm.

Still, the count is strong enough for Broderick and others to call the Jenner Headlands Hawk Hill North.

"There's a lot diversity, a lot of different raptors coming though, some of them in high numbers, some of them just solo birds," Barry said.