Wednesday, October 20, 2021

Red-tailed Hawk Catches Mid-day Squirrel Meal

Captured images in early 2020 of a red-tailed hawk—from initial perching on first tree to perching on second tree with its captured squirrel meal. View the video for the six sections.

Red-tailed Hawks, Segue to Additional Hawks

Various sites display basic info about this hawk's length (slightly less than two feet), weight (3 pounds, give or take a few ounces), wingspan (four feet or so), and scientific name (Buteo jamaicensis). The following sites helped me obtain my own bird’s eye view for hawks:

  • "Red-Tailed Hawk" provides some basic info about this distinctive bird of prey.
    Genders are similar with brown mottling on the upperparts, though the amount of white in their plumage can vary greatly. ... Red-tailed hawks are commonly seen perched on poles, fences, or trees near roadsides as they scan fields for prey.
  • "Interesting Red Tailed Hawk facts" provides loads of images in describing 13 facts. All facts interesting, the most significant to me were ones that addressed hunting capabilities and territory.
    They have a very keen eyesight that is 8 times as powerful as a human's, ... In flight, this hawk travels at speeds from 20 to 40 mph (64 km/h); however, when diving to catch prey, their speed may exceed 120 mph (190km/h) ... They tend to keep the same territory their whole life; it can be as large as 9.6 square miles (25 square kilometers) ... The birds defend their area with aerial displays of steep dives and climbs, ...
  • Red-tauked Hawk” has basic info, habitat map, and link to a YT video that features several calls. Visit the rest of the hawk section to compare and contrast it with other hawks. For further distraction, peruse the site for even more raptor species info.
  • "Texas Hawks and How to Tell Them Apart" provides good guidance with pictures, descriptions of features, and comparisons among the various species. (The info about the red-tailed hawk is the first listed species.)
  • "14 Species of Hawks in Texas (With Pictures)" is well- organized with length, weight, wingspan info in addition to descriptions and pix. As in two preceding resources, the red-tailed hawk is the first section on the list.
  • "Identifying Raptors" primarily features the red-tailed hawk. To a lesser extent, the video discusses a few other hawks, but not other predator genuses. (The title is misleading because of "raptor" in the title.)

Bird Parts and Wing Parts

This section is an overview about bird and wing identification. (I had run across some sites about red-tailed hawks and other hawks that mention terms unfamiliar to a non-birder such as myself.)

  • "Parts of a Bird" introduces basic anatomy, accompanied by an image with identifiers: head, neck, back, rump, tail, undertail coverts, wing, leg, foot, flank, abdomen, chest, throat, chin.
  • "How to Use Wing Structure to Identify Birds introduces wing anatomy, accompanied by two images (in flight, perched) with identifiers. These labels were especially helpful for several sites that used the terms: wingtip, wrist, patagium, coverts, primary feathers, secondary feathers, wingspan, wingpit. "Patagium" was  totally new to me; several other terms more clear to the part they pointed to.

Curiosities During Research

As I started viewing and editing stills and videos to organize a video, several questions came to mind:
  • Are all predator birds raptors?
  • Do birds of prey stake out territories and become familiar with areas?
  • How does a hawk hunt and capture its prey?
  • Why do some birds' feathers reach ankles?
  • Are leg feathers more common among predator birds?
"Why is a bird of prey called a bird of prey and what is it?" explains bird of prey and raptor meaning the same thing:
The victorian scientific name for birds of prey is RAPTOR. This name comes from the latin word meaning a Plunderer – someone who seizes and carries away. That is pretty much what birds of prey or ‘raptors’ do – they seize, or grab their prey and carry it away.

"Raptors" is a good introduction to the four groups of raptors. If interested in more, Googling each type results in much more information. (A little odd to me was the very short eagles section.)

Hawks: "genus Buteo ... broad wings ... powerful feet and strong talons to bind to their prey constricting it in their grasp and puncturing vitals" (noting red-tailed hawk in this group)
Accipiters: genus Accipiter ... short wings ...constant state of motion" (noting Cooper's Hawk in this group)
Eagles: "genus Aquila ... long, broad wings"
Falcons: genus Falco ... longwings” (noting Peregrine Falcon in this group)

"Top 20 Amazing Facts About Hawks" shows great images to go with their listed facts. The five I pasted are the most noteworthy, two of them pertaining to sight. Two others  pertain to my curiosities about hunting characteristics. The "mantling" interested me because my footage showed the hawk's seeming attempt to shield its squirrel upon return to the first tree.

Hawks have excellent eyesight. They can see up to 8 times more clearly than the sharpest human eye ... Hawks are able to catch prey both in the air and on the ground. They use their talons to both catches [sic] and kill their prey ... The bird may eat on the ground or carry its kill to a feeding spot, often a fencepost or tree limb, where it plucks its prey and tears the meat apart with its beak ...Hawks can see colors, like most humans can, as well as those in the ultraviolet range ... Hawks will frequently "mantle" prey, crouching and spreading their wings to form a shield that hides it from other predators ...

"How Do Hawks Hunt? (7 different methods & how to observe)" is informative for the names and descriptions of the methods. The hawk I recorded definitely used the perch and swoop method. The article's accompanying image is very similar to my hawk pix before its descent to capture the squirrel.

In viewing my subject red-tailed hawk's images and clips, I noticed feathers around its legs that made them puffy-looking, maybe exaggerating leg girth. I thought about images of eagles with feather-loaded legs, wondering if raptors typically had feathery legs, unlike lots of birds and poultry that are bare-legged. "Rough-legged Hawks and Feathered Feet" clarifies:

most hawks and eagles have bare legs, ... Eagles in the genus Aquila, which includes Golden Eagles, all have feathered legs, but the hawks of the genus Buteo include both feathered and unfeathered types.

Odds and Ends

A significant part of my topic's effort pertained to items (camera, graphics tools) used, parameters, and image/video post-processing.

Camera: Canon PowerShot ELPH 190 IS
Stills: 5152 x 3864 (cropped, some composited/reduced to 1280 x 720)
Vid: 1280 x 720, 25 fps

Tools:
GIMP 2.10.8 (color/contrast, scaling, cropping, captions)
OpenShot 2.4.3 (video editing)
Kdenlive 6.12.0 (image stabilization part of video editing)

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