I came across an interesting video put together by Danny Joe Humphrey some time ago that seems to have gone mostly unnoticed by the Roller fraternity. As some of you probably know, Mr. Humphrey is mostly well known as a breeder of Color Pigeons or German Toys and used to produce an internet show called "Color Pigeons and More". He also breeds and flies a few rollers from James Turner.
Like everyone else, Mr. Humphrey has suffered many roller losses at the hands of Birds of Prey. What he had to say on the subject, despite it being only a very short video and having only a few hundred views, is rather important and could very well save thousands of valuable rollers if Roller breeders would bother to listen.
In the video, Mr. Humphrey explains that in his youth, when Crow hunting was a popular past time, it was well known that the best time to hunt crows was when the birds were getting ready to roost for the night, about an hour before sunset. At this time in the day, they started to settle in for the evening and were very easily hunted because of their inactivity during those hours.
Mr. Humphrey also deduced that hawks and falcons share similar roosting habits to crows and therefore also start become inactive near sunset. He then goes on to explain that he has been flying his kit at sunset and has not, in that time experienced a bird of prey attack on his kit.
Now I firmly believe that Mr. Humphrey is on to something here.
I have bred and flown Rollers of several breeds, as well other types of flying pigeons since the 1970's. My first problems with Birds of Prey began in late 1988 and reached devastating proportions by the Fall of 1990. During the 1990's I tried everything under the sun to try to either reduce, or least offset the losses in an effort to actually salvage something resembling a holdover kit. Some years those efforts included simply flooding the sky with as many young birds each year as I could. In 1988, I banded 50 or so young birds, which increased to 75 in 1989 and to 125 in 1990. By 1991, I was breeding 150 youngsters per year. By 1994, that number had increased to 350 young birds per year. That's a lot of young birds to try to fly out, but it seemed that the more birds I bred, the more birds I lost and come the next breeding season, no matter how many young birds I had bred, I still only had a few dozen of them left. Generally speaking, the best performers always "got it first" from the falcons. And what's more, I wasn't the only one suffering from those types of losses. Every breeder I spoke to was experiencing the same type of troubles. Contrary to the claims of non-roller fliers, these hawk losses were not simply limited to the migration season.
Interestingly enough, based on my best recollections of those years, the vast majority of my losses took place either early in the morning (when Big Bitch Cooper was patiently waiting for the first kit to go out the door) or at the height of the afternoon. I cannot recall a single incident of a bird of prey attack having started within the hour before sunset, though I do have a few memories of Peregrine Falcons pushing kits up "into the pins" in the very late afternoon to try to wear them down. I never lost many this way, because as twilight rolled around, they always seemed to break off their attacks and leave the areas. 95% of the time I could drop the kit as dusk rolled in and even when I couldn't, I never lost any to overflies unless they were squeakers and not completely used to flying at excessive heights.
Needless to say, my personal experience certainly jives with Mr. Humphrey's suggestion to fly your kit at sunset to avoid hawk losses.
So what do ornithology experts have to say on the subject of Bird of Prey roosting behavior?
First things first, there are two basic groups of birds that exist due to evolution and adaptation. The largest group are those which are considered "Diurnal", which is according to one source defined as "birds that are principally active during the day with all major life activities, including courtship, nesting, feeding, preening and other behaviors. Most species of birds, including songbirds, hummingbirds, waterfowl and raptors other than owls are considered diurnal. Diurnal birds roost and sleep at night and become active again when the sun rises." In contrast to this is the small group which are Nocturnal, which are principally active at night. While Owls are nocturnal, most birds of prey fall into the diurnal category. As well, though many diurnal bird species often adopt nocturnal habits during their migrations and have been witnessed flying at high altitudes during the darkest of night, as Raptors like hawks and falcons rely on daytime thermal currents to migrate, they do not adopt these types of nocturnal migration habits that species like Canada Geese do. In fact, it is believed that many diurnal birds often travel great distances at night while migrating as a means to help avoid predation by Birds of Prey.
That being said, Peregrine Falcons have been known to feed their young cached kills late at night, though no research has uncovered them actually hunting at night.
This being said, it is a scientific fact that the nemesis of our Rollers is mainly a diurnal bird, and the same as pigeons, have a natural instinct to go to roost for the night.
The question then becomes, at what point in the day does this instinct to go to roost take its effect?
According to scientific research, the answer to this question may actually differ by species.
In a study by Roth and Lima published in 2007, entitled "The predatory behavior of wintering Accipiter hawks: temporal patterns in activity of predators and prey", it was noted that the roosting behavior of the Sharp-Shin Hawk and the Cooper's Hawk differed greatly in that "During the winters of 1999–2004, twenty-one sharp-shinned hawks (A. striatus) and ten Cooper’s hawks (A. cooperii) were intensively radio tracked in rural and urban habitats in western Indiana, USA. Cooper’s hawks left roost before sunrise and usually returned to roost around sunset, while sharp-shinned hawks left roost at sunrise or later and returned to roost well before sunset."
You can read the full paper here.
While it appears that the Cooper's Hawk may hunt later into the day than the Sharp-Shinned Hawk, they still seek out their roosts by sunset. It is suggested that the reason the smaller Sharp-Shinned Hawk may seek out the protection of its roost earlier than the Cooper's, is that due to its smaller size, it is far more vulnerable to attack by Owls which start to become active during dusk.
Unfortunately, while there are numerous studies about the hunting behavior of Hawks and Falcons, very little research has apparently been done to document their peak hours of hunting.
That being said, Mr. Humphrey's suggestion to fly your kit around sunset and his experience doing so does seem to jive with what research has been done on the subject. At bare minimum, the suggestion is good enough to see if it helps cut losses and in fact, I've been utilizing the advice for a long time now with some success now. The only hawk encounter I've seen was a female Cooper who cut up one of my hens in an outdoor individual pair coop. The hen is recovering and the hawk has not returned. Knock on wood.
Obviously, some roller fanciers will be a little leery at first to fly their kits relatively late in the day, but just the same as the hawks do, our rollers have a natural urge to go to roost at night. Provided you cut the feed a little to insure that they only fly for 15 to 20 minutes, the risk of loss would be a very minimal one until the birds get used to flying at this time.
That being said, it would still be best to train your squeakers at a more reasonable time in the day to reduce the risk for those that always seem to insist on ranging away from the loft a great distance at first from spending the night out on a rooftop somewhere. Once the young kit is used to flying a fancier could gradually start to get them more used to flying later in the day.
Try it; it may just save those good ones for you.
~ Jack
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