Before getting to the raptors, let’s start with something that at least the larger ones might like to eat. This rabbit was out walking on Monday and twice dropped by to help me put the finishing touches to this week’s Wednesday edition.
Raptors
… the scientific name for what are commonly known as birds of prey. Whatever you name them, most people go “wow” when they see one.
These charismatic birds are by no means as rare or as hard to spy as some may think. Sharp-shinned, Coopers, Red-tailed and Red-shouldered Hawks all hunt within our locality and some species breed here ... albeit their nests tend to be in the quieter and harder to reach corners. In recent years Great Horned Owls have been heard just down the road where there are good stands of mature trees in gardens to nest in and excellent hunting around town and in the adjacent McGill campus. Not long ago, a pair of Red-shouldered Hawks nested and raised young in a tall shagbark hickory tree within yards of one of the main trails in the Arboretum, yet perhaps only three or four of the many visitors that use that “highway” ever noticed them. The adults will have most certainly noticed you though, if you got too close.
Especially evident in spring and summer, less so in summer, are individual or small groups of Turkey Vultures riding the thermals to gain height and spy out a ready meal. These magnificent birds can be identified simply by their size but also by the characteristic ‘dihedral’ (that just means a shallow V-shape) set of their wings as they float above, hardly flapping at all.
Merlins are small raptors about the size of a Crow that often nest in tall trees in the town and are can be found around the edges of the forested areas nearby. You will probably hear them before you see them - in fact you may not see them at all but they call to each other with a characteristic cry that you can discover from recordings found on the internet.
Other raptor species can be seen from time to time within their hunting areas or flying over during spring and fall migration periods when the skies, if you look high and hard enough, can on occasion be speckled with these birds passing through on their way to and from their breeding territory. The West Island of Montreal is within one of the migratory flyways for raptors and it is well worthwhile searching the sky above during the appropriate periods of the year. Mind you, you will need good optics, binoculars or a spotting scope, to identify most of the species.
During the summer, I will be checking the fields south of the arboretum between it and the highway, especially for Red-tailed Hawks that hunt the open margins of the highway and use the forest edge as a base. Maybe you have similar habitat nearby?
Especially in the winter months Sharp-shinned Hawks and the similar Cooper’s Hawks visit garden feeders in search of smaller birds to catch and eat. We put out seed for small birds and thereby provide small birds for raptors - all part of the food web.
There are raptors such as the Bald Eagle and maybe even Golden Eagle that come through on their way further north to breed or to depart southwards at the end of the year. Near me, if you are in Ste-Anne-de-Bellevue at the right time of the year go to the locks on the river and look across towards the small islands. I have several times seen Bald Eagles sitting quietly in the trees there just posing for photographs.
Anatomical Adaptations
It is easy to think that “sharp beaks and talons” define the anatomy of raptors, but there is more to it than that. Those features are differently adapted species by species to suit the prey they most often seek. For example, beaks differ quite a lot
Some birds have hooked beaks for tearing flesh from a catch - Eagles, for example
Notched beaks are used for killing by Falcons whose beaks are equipped with a sharp triangular-shaped ridge on the outer edges of the upper mandible which they use this to kill prey quickly by biting their necks and severing the vertebrae.
Serrated beaks evolved with Ospreys for better dealing with slippery fish
Now, looking at a few species in more detail:
Note - Owls are also raptors, but I will deal with them in a separate article.
Coopers Hawk
Personally, these are the hawk that we see most often. Not simply because there are quite a few of them around, but because with our garden’s array bird feeders there is almost always a potential meal for them to check out. Fortunately for the potential snacks the Coopers Hawks are often not all that successful at doing much more than scattering the feeder birds to the four winds.
Cooper’s Hawks are forest birds that move fast and easily amongst the trunks of trees. Nevertheless they have adapted to city parks, and gardens with bird feeders. When they decide on a potential meal they don’t usually fly at them in a straight line but attack in curving swoop, catching prey mid‑flight as they try to escape. Like all Hawks their eyesight is acute and they can spot a tiny sparrow moving among dense foliage from a great distance and seemingly then calculate the perfect angle to intercept it.
They take their common name from William Cooper, a 19th‑century naturalist who first described the species. That name, however, is likely to change soon. The American Ornithological Society are working to change the common names of all American birds on the AOS official checklist that are named after individuals. The reason being that a good number of those individuals are today considered to be of maybe dubious character in a historic light. That, and the fact names of people don’t really tell you much about the bird so kit easier and cleaner to update the common names.
Merlin
Merlins are rather special. There are always a couple nearby our home in the spring and summer heading out in search of food from their nests high in some tall and mature garden tree.
They are small, agile falcons (Falcons being different to Hawks) that are found not just on this continent, but also throughout Eurasia. Adults are about 30 cm (12 in) in length with a wingspan of 65–85 cm (26–33 in). Depending on where you find them in their range their plumage is different, with North American birds being generally darker than Eurasian specimens which have a lighter, brown‑gray colouration. They hunt by swift, low‑level flights, going after songbirds and very often dragonflies. Some years ago in the nearby arboretum I recall a lone, old tree in a field which had Merlins nesting at the top and we would often watch them from the edge of the field as they snatched up passing dragonflies.
Folklore erroneously links merlins to the legendary wizard Merlin, whose name was assumed to be derived from an Old Welsh word for “bird of prey.” However, sorry to spoil the party, but the name “merlin” for the bird is derived from the Old French word “esmerillon.” This name is quite unrelated to the wizard Merlin, whose name comes from the Welsh personal name, “Myrddin.”
Bald Eagle
At the other end of the size scale to Merlins, Bald Eagles measure 1.8–2.3 m (6–7½ ft) from wingtip to wingtip. Adults have a characteristic white head and tail contrasting with a dark brown body and wings though they are around five years old before that develops. Look for them near water where they hunt fish, which is their primary food … along with scavenged carrion or sometimes they will take waterfowl.
Their nests, are huge platforms and placed high on tall trees or cliffs ledges and can be over 2 m (6 ft) across after several seasons use.
Osprey
Also known as “fish hawks,” these birds are of moderate size, some 55–60 cm (22–24 in) in length with a 140–180 cm (4.5–6 ft) wingspan. They nest in tall trees, cliffs, or often around my home on artificial platforms set atop poles near water. Nesting platforms may be reused for decades.
They are obligate fish eaters, diving feet‑first at up to 120 km/h (75 mph) to take fish from the water prey, a task made simpler by then having reversible outer toes and barbed foot pads that grip slippery scales. After DDT decimated populations in the mid‑20th century, bans and conservation efforts helped them rebound dramatically
Northern Harrier
Another medium‑sized raptor to be found in wetlands, grasslands, and open forests. Adults are 40–55 cm (16–22 in) long with a wingspan of 95–115 cm (38–45 in) and weigh 300–600 g. These, I think rather wonderful, birds have a broad, rather owl‑like facial disc that helps collect sound helping them locate prey such as voles, mice, and small birds while they glide low and slow over fields and wetlands. They have been described as “mowing” the landscape in a characteristic, wavering flight. Something I love to watch is their ability to hover momentarily by beating their wings rapidly, this facilitating their hunting success in marshy habitats where cover is scarce
Nests are concealed on the ground under dense vegetation.
Far more interesting , and knowledgeable than crows and rooks. presuming that i am aware which is which. At the present time I am more interested in the number of black squirrels that visit my garden. Rogue, our border collie, supplies the entertainment, i.e. how do I climb this darned tree?
Brillaint breakdown of the anatomical specializations! The osprey adaptations are partciularly wild when you think about how precise those reversible toes need to be at 75 mph. I saw an osprey miss a catch once and the recovery dive it pulled off was insane, just pure muscle memory. Makes me wonder if there's a learning curve for juveniles or if its mostly instinctive from the start.