been confirmed by ornithologists, those scientists who study birds.
Northern harriers' diets vary with time of year and in different habitats, but they seem to prefer small to mid-sized rodents. They also will eat reptiles, frogs, small waterbirds and perching birds, like meadowlarks and northern cardinals. Northern harriers, especially recently fledged ones, will even eat insects.
Some raptors, like peregrine falcons, will dive on their prey at high speeds. Others will hover and pounce. Ornithologists have classified northern harrier hunting flights into four types. The first is prolonged, non-flapping gliding, and the second is a more or less straight flight with lots of flapping and little turning. The third type also has a lot of flapping but also a lot of turns over a short distance, while the final type is stealthy and used by a harrier following a landmark, like a fencerow, at relatively low altitudes, perhaps less than 25 feet above the ground.
Regardless of the type of hunting flight that is being used, once a harrier finds a possible food item it will then pounce on the prey and try to catch it. But the success rate of pounces is variable and depends on the habitat, the kind of prey and the age or sex of the harrier. In rough order, it is easier for a harrier to catch a reptile or amphibian than it is to get a small mammal, which in turn is easier than a bird.
For some reason, adult males have higher hunting success rates than adult females, and, of course, just based on hunting experience, an adult will have more success hunting than a juvenile. All of that leads to a pretty obvious conclusion: if a harrier is in tough hunting habitat, is chasing birds and is young, it's going to have to do a whole lot of pouncing to get some dinner.
Even after a successful hunt, a harrier may not eat immediately. For example, if it is during the breeding season and the female is sitting on a ground nest, the male supplies food to his mate. Sometimes, if there is quite a bit of food available, mated harriers will cache supplemental food nearby.
Males announce their territories and court females by executing something that has been called the "sky-dancing display," which can be a spectacular exhibit with as many as 74 U-shaped undulations strung together in flight over a