Pets, Animals - Birds
Eagle Valley is a 1450-acre preserve along the Mississippi River privately owned and managed by Kohler Co. and Kohler Trust for Preservation. Its wooded bluffs, prairie, and river frontage are home to several nesting pairs of Bald Eagles; 87 other bird species have been documented as confirmed or probable breeders on the property. The rich and diverse habitats are also home to dozens of mammals from White-tailed Deer to Masked Shrews, various amphibians and reptiles, including Timber Rattlesnakes and Snapping Turtles, and many other species. In addition to providing an important stopover for birds migrating along the Mississippi, Eagle Valley provides a winter home for hundreds of Bald Eagles, many of them from Canada. Deep, fast-flowing stretches of the river remain open even during the coldest winter weather, providing the eagles and many other animals with a rich source of food and water during that cold, lean season.
Eagle Valley staff has been actively researching raptor ecology since 1989. Projects include raptor migration counts, studies of Bald Eagle winter night-roost dynamics, and eagle satellite tracking. Through these efforts, a great deal has been learned and shared about the eagles that overwinter here and the ecosystem that supports them.
Over the past quarter century, there has been a dramatic return of eagles and nests to the river below. Through a solar-powered wireless system that includes a pan/tilt/zoom camera, a small solar panel (mounted well above the reach of spring floodwater), and two wireless relays – one to pass the signal from the nest to the top of the bluffs, and another to pass the signal from the bluff tops back to the research station at the valley’s head – the nest and eagle activity are available to a wide audience.
The nest we are watching is located just west of Eagle Valley on the Upper Mississippi National Wildlife and Fish Refuge in southwestern Wisconsin. The eagles at this nest have been fledging young since approximately 2007. The Eagle Valley nest camera is a joint venture between Kohler Trust for Preservation, Raptor Resource Project, Kohler Co., and the U.S. Fish and Wildlife Service. Faith Technologies was instrumental in much of the initial system installation. Personnel from all partnering organizations participated in planning and execution of the nest camera installation.
We hope you enjoy it!
October 14, 2013: Camera mounted above eagle nest
January 16, 2014: Began streaming live on RRP's Ustream channel
March 27, 2014: First EV egg (EV1) laid at 4:08 P.M.
March 30, 2014: Second EV egg (EV2) laid around 7:50 P.M.
May 2, 2014: EV1 pip
May 3, 2014: EV1 fully hatched around 11:00 A.M.
May 5, 2014: EV2 pip, then hatched 7:30 P.M.
May 13, 2014: Suspected Great Horned Owl predation on one of the chicks at 10:17 P.M.
Explanation of probable Great Horned Owl (GHO) predation of Eagle Valley eaglet on May 13, 2014 at 10:17 PM Central DST:
May 13 was a nearly full moonlit night with a few clouds. While we do not have an infrared camera, there was often enough light to discern the outline of the head, and sometimes tail, of the adult female and to a lesser extent the outline of an eaglet, especially when it moved, just to the right of the female prior to the attack.
The quick attack approach at 10:17:07 was silent (no wing beats heard, suggesting owl, and no climbing mammal sounds); then a “thud” sound was heard, which we presume was the GHO grabbing the eaglet, then the sounds (and visual) of the adult female eagle stepping to the right side of the nest and calling as the owl flew to the right. The attack took just a few seconds. The outstretched owl wings briefly blocked the view of the adult female eagle head during the attack. The adult female continued to call often, facing right. Then at 10:18:35 she moved back to the nest bowl; more calls from her. At 10:19:30 eagle wing beats are heard – either the adult male flew close by or the female flapped her wings. Only one adult was visible at the nest. The adult male was heard nearby at 10:21:33. A few more calls from the female were heard during the next few minutes.
Owls have a clear advantage at night, with their extraordinary night vision and acute hearing ability. In my experience, Bald Eagles very rarely fly at night, though the Decorah eagle nest camera has documented, in a previous year, an adult eagle flying at least several feet or yards to defend the nest from a raccoon attack under a well-lit night sky. GHO’s are powerful and opportunistic hunters. This incident illustrates the sometimes harsh reality of life in the natural world.
We spent most of the afternoon of May 29 troubleshooting our video and audio stream, which had been choppy for most of the day and then unexpectedly quit around 2 p.m. CDT. All involved quickly and efficiently identified the defective hardware and ordered a new part.
Update on Eaglet:
The part had not yet arrived by Monday (June 2) morning, but we were anxious to check on the eagles, so at 9:10 a.m. we took our laptop to the relay site at the bluff edge and plugged in there to view the live stream. To our great disappointment, we discovered the eaglet was no longer alive. Its death was recent, within the previous 24 hours. At 9:25 one of the adults landed on one of the favorite nearby perches and was heard calling with another out-of-view eagle.
While we have no video verification of the cause of the eaglet’s death, based on our observations and experiences the past several days, we strongly suspect small, swarming flies/gnats constantly annoying, plugging airways, and perhaps biting the eaglet likely led to its demise, despite the parent birds’ attempts to hover over to protect and even pick the insects off of the eaglet. Based on the completely intact body, which appeared to have food in its crop and ample fat reserves, predation and starvation were ruled out as possible causes.
Though this is the first year we have had the camera over this nest, we watched this nest closely last year with binoculars and spotting scopes as they successfully fledged two young. We believe that this year’s pair is the same pair as last year’s.
We are grateful for your participation in our glimpse of the natural world and appreciate your positive comments. We will continue to share views and all of the sounds from the nest area once the system is fully operational again.
Update: Live streaming restored
The defective part for the antenna has been replaced. After some testing to ensure everything was working properly, we resumed broadcasting to Ustream on Thursday, June 5 at 6:30 a.m. CDT, when both adult eagles were perched near the nest.