Learning to determine between one type of bird in relation to another by its size and shape is a skill that sets you well on the way to nailing down that bird (not literally). But there are so many birds out there that are pretty much the same dang size, and unless you’re comparing an owl to a pheasant, that whole shape thing can be quite similar, too – head, wings, body, tail. That’s where mastering the next step comes in.
Consider what your target bird actually does – how does it walk, fly, feed; even the way it sits can set it apart.
Consider what your target bird actually does – how does it walk, fly, feed; even the way it sits can set it apart from another closely related species. This step usually helps back up what you have already surmised from your initial thoughts, but it can also be the deciding factor in an identification, especially if the lighting isn’t in your favour, or with birds that are just that bit too far away to get a full visual assessment. For example, you may see a whole load of waders feeding far away on a mudflat, but you can just about see a few of them sweeping their beaks side to side through the water lapping at the edge, rather than poking straight down into the mud that is out of the water – this means they are avocets, whose bills are shaped just so for that sweeping manoeuvre, skimming insects from the surface.
Each bird species will have a unique way about them, such as the aptly named wagtail, or the dipper, and it will take practice to recognise these, as with all things. But in some cases, and eventually with many, it can be as familiar as spotting a friend in a crowded place.
An Eurasian wren is about the same size and shape as an Eurasian nuthatch, and both occupy the same habitat, but you should be able to tell these two apart in fading light or silhouette by the way each behaves. A wren darts in a low flight between adjacent piles of brush and bracken and cocks its tail upon landing, often bolt upright on a prominent outpost, whereas a nuthatch moves in short bursts, up and down trees and staying close to them with its body held low but the head will be held aloft in an upward curve, pausing every few seconds from its progress to look rapidly this way and that and then hammer away at the bark before moving on. One glance at each of these birds in the dusk-light will eventually be all you need to know which is which.
Shoulders back, back straight!
A word that some of us may be familiar with is “posture”. Sat here writing this, I sometimes recall that one specific teacher sharply berating me for my own posture, and must remind myself to sitproperly at the desk. Posture is the behavioural aspect ofhow a bird presents itself. Often, just the difference between horizontal versus vertical posture - does the bird stand upright or keep its body close to a surface when it is still? – is a good attribute to figure out first, as this is unique to a species. Posture mixes in with the whole size and shape elements of a bird, and can help you determine between birds that share similarities for the first two aspects.
Movers and shakers
When a bird moves, you get the double whammy of useful information – you’ll likely see more of the wings and tail when it moves, but also, it’s whole character will be in the non-flying movements it makes. Some birds skulk, like a towhee, and some birds are bold and walk upright, like crows. Sparrows hop, larks scuttle, ducks waddle, ostriches lope, sanderlings run like clockwork toys, pigeons move their heads back and forth with each slow cautious step.
Posture is the behavioural aspect of how a bird presents itself.
If it is on the water, does the bird dive with its whole body under the surface, or does it just put its head in? Some water birds are known as diving ducks and will completely submerge themselves, and pop up a bit further downstream like the goldeneye ducks, or eiders, and mergansers. Those that just dip their head in and tip up their rear ends are known as dabblers, like the mallards, wigeon, pintail and teal.
Two's a crowd
Another facet of behaviour is how sociable is this bird? You will rarely see great tits or a starling alone, or a heron or kingfisher in a flock. Some birds will congregate en masse like godwits along a shoreline, whereas the curlew among them will be solitary, maybe one or two within a few metres, but will have that distinct air of “he’s not with me”. Waterbirds do usually tend to be gregarious, the official term for sociable in the bird world, so even if they are not inclined to hang out with their own species, they will be content to share the same beach with many others. Geesewill always be part of a crowd of other geese, even those that occupy noisy and busy public parks like the Egyptian geese in Hyde Park, London, UK.
How a bird forages is incredibly noteworthy. This can be where watching birds of a similar size can get illuminating. Thrushesflick leaf litter out of the way as they walk through it, searching for insects underneath. It is rare to see a swallow land on a surface, they feed“on the wing” catching insects in their wide and flat mouths. Flycatchers, robins, and redstarts jump out and up from perches to catch their passing prey, but when they land, note the difference – flycatchers stand stock still, head occasionally turning this way and that, whereas robins and redstarts cock their tails when landing, and redstarts almost always make their pebble-grinding call as well, just after landing.
Flying high and low
Lastly, a very helpful tell-tale sign of what species you have in front of you is how it flies. This may sound nuts at first, especially as the very act of flying means you usually only get to see it for a few seconds, but once you’ve understood the principles of how a bird can actually get itself into the air given its specific shape and size, the movement of the flight itself makes sense.
In good field guides, you may notice squiggly line drawings on the page for each bird. This describes the movement of the bird in flight for a few seconds, representing the usual pattern that bird would display through an uninterrupted moment in time. There are generally only a few ways a bird can fly, and that will always be governed by its wing shape, which in turn is always governed by its body shape.
In good field guides, you may notice squiggly line drawings on the page for each bird.
Lot of smaller birds like tree and wall creepers, sparrows, finches and buntings fly like a “rollercoaster”, where they flap their wings like crazy for a few seconds, and then fold them in so that they drop down some distance, then flap for height again, then drop and so on. Woodpeckers also do this, but on a much more exaggerated scale. Larks adopt a similar style, but they stop flapping for less time, really just a short glide, so they don’t lose much if any height. Tits and warblers tend to restrict themselves to short rapid bursts of flight between shrubbery. Direct, methodical and consistent flight is usual for medium to larger birds who cover relatively longer distances like crows, shrikes and orioles. Large birds like herons, eagles, cranes and many sea birds or large migratory birds like geese will have slow and steady wing beats. Swallows, martins and swifts will have short bursts of rapid wing beats and then glide and soar for long periods of time in the thermals. Pigeons have an unmistakable flocking flight at certain points of the day, where in groups of usually ten or more birds they will fly in wide circles, flapping all the time. Larger birds of prey like buzzards will also take advantage of the afternoon thermals and glide in huge arcs through the summer skies. But birds of prey are a class all of their own, and in a later post, we discuss their flying styles among other things, to help you discern between the types.
Identifying a bird based on these components of behaviour is not usually achievable in isolation, but it is still possible, and as with most of the steps taken in bird identification, these methods are sometimes more effective when used in a negative context: does this bird fly in a straight line out in the open? No? Then it isn’t a crow. Does it feed whilst swimming on the surface of the water? No? Then it isn’t a duck. It may sound flippant, but often the best way to ID a bird is to figure out what it is not, so you can avoid huge chunks of your field guide altogether, and then take it from there.
Finally, don’t forget it’s the Great Backyard Bird Count this weekend, organised by The Cornell Lab of Ornithology. A US-based organisation, this bird count is for anyone in the world to take part in and is a perfect opportunity to practice your ID skills at the same time as contributing extremely important data. You can download the renowned Merlin ID app which has info on species from 7 continents and is available in 8 languages. For more information and how to sign up and submit your results, click here.
