Daniel D. Berger was born in Milwaukee, Wisconsin, on 17 July 1932, and passed away from cancer at the age of 84 on 27 December 2016 at his home in South Pasadena, California. Several things defined Dan and his significant contributions to raptor research: his life-long passion for birds of prey, his remarkable capacity for commitment, his intelligence, his propensity for confident independent thinking, and his playful wit.
All of these shaped the contribution he is perhaps best known for—the co-founding (with Helmut Mueller) of the modern Cedar Grove Ornithological Station (CGOS), on the Wisconsin shore of Lake Michigan. CGOS was the first, and today remains in operation as the oldest, migratory hawk trapping and banding station in the world.
Staff of the Milwaukee Public Museum trapped hawks at the Cedar Grove site intermittently in the 1930s and early 1940s. The distraction and demands of World War II brought the museum's efforts to a close and in the fall of 1950, Dan and Helmut, then 18-yr-old boy birders from Milwaukee, showed up and re-occupied the museum's abandoned shack and trapping blind. They were trespassers, squatters, but they never left, and thereby founded the modern operation. In the ensuing 67 yr, until his death in 2016, Dan missed only three fall trapping seasons at Cedar Grove—and two of those were near the end of his run, due to consequences of the cancer that eventually took his life. His decades at CGOS embodied a remarkable commitment to raptor research.
At CGOS, Dan and Helmut were the first to make hawk migration an object of sustained scientific study. Cedar Grove set the example that other raptor banding stations around the world have emulated, and they invented or re-introduced many of the trapping techniques used today. During the 1960s, in the trapping off-seasons—springs, summers and winters—Dan collaborated closely on other raptor research projects (such as studying nesting Northern Harriers (Circus cyaneus) in the spring and summer, and trapping and banding Snowy Owls (Bubo scandiacus) in the winter) with two prominent Wisconsin friends who were among the founders of the Raptor Research Foundation, the late Frances and Fredrick Hamerstrom.
In August 2017, the authors of this memoriam, two of the many of trappers Dan mentored at Cedar Grove, returned to the station, to set up bownets, mistnets and dho-gazas for the station's 68th consecutive season, the first without Dan at least guiding from a distance. As usual, as we pulled various pieces of equipment out of storage, we marveled at Dan's mechanical aptitude and technical ingenuity in the designs of bownet and dho-gaza releases, mistnet riggings, and other gear. He was a masterful, creative tinkerer, and his smarts are everywhere reflected in either the elegant pragmatism or the wild ingenuity of countless pieces of Cedar Grove's equipment. Of course, some of his innovations didn't quite take, such as the “jumping dho-gaza,” but he would be the first to laugh at the memory, and add a self-effacing jab with his ready, sharp wit—and then carry on—always trying, always tinkering.
Another major passion and leitmotif in Dan's lifelong involvement in raptors was the restoration and conservation of Peregrine Falcons (Falco peregrinus). At the November 2015 Annual Conference of the Raptor Research Foundation in Sacramento, Dan was an invited participant on the panel commemorating the 50th anniversary of the Madison Peregrine Symposium; 83 yr old at the time of the Sacramento meeting and struggling with cancer, Dan left the Cedar Grove banding station for what would be his last time and drove to Sacramento, more than 3400 km, embracing his legendary frugality by sleeping along the road en route. At the 1966 Madison gathering, organized by the late Professor Joseph Hickey, Dan shared the results of his surveys for nesting peregrines along the upper Mississippi River in the 1950s and early 1960s, and his important survey of 1964, with Charles Sindelar, of known peregrine eyries in the eastern United States and adjacent parts of Canada. It was that latter, comprehensive survey that documented the extirpation of the eastern peregrine as a wild breeding species.
With the disappearance of peregrines from Wisconsin and the eastern U.S., Dan turned west, and worked for fifteen spring and summer seasons in the 1970s and 1980s with Jerry Craig of the Colorado Division of Wildlife (and also the late Jim Enderson; JRR 51:393-395), rappelling to eyries up and down the Colorado Rockies in an effort to conserve Colorado's nesting peregrines. And when Peregrine Falcons eventually returned to nest on cliffs along the upper Mississippi River, so did Dan—he was involved in banding peregrines there into his 80s. Interspersed in these efforts was a survey for nesting peregrines in the far north, the Ungava Peninsula of northern Quebec, and in the south, an attempt to trap spring migrant peregrines on the Dry Tortugas in the Caribbean. For more than five decades, where peregrines were found, and help conserving them needed, Dan was often close at hand.
Unwavering commitments to Cedar Grove Ornithological Station and to peregrines are the cornerstones of Dan Berger's considerable contributions to raptor research, and this is documented in the dozens of scientific papers on which he was an author. The fact that CGOS and Peregrine Falcons both survive today, and that those Dan mentored and inspired are involved in the perpetuation of both are his significant legacies. While his legacy endures, we will miss Dan, especially his stories, wit, and laugh.
