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Five Hawks Down: watch the tragic migration of six Californian raptors
Tracking project establishes northern Argentina is wintering ground of Swainson's hawks
- Watch these six dots move across the map and be moved yourself: this is a story about coming of age, discovery, hardship, death and survival.
- Each dot is a tag attached to the talon of a Swainson's Hawk. We follow them on their very first migration, from northern California all the way down to Argentina.
- After one year, only one is still alive.
Discovered: destination Argentina
Young Swainson's hawks were found to migrate to northern Argentina
The Buteo swainsoni is a slim, graceful hawk that nests from the Great Plains all the way to northern California.
It feeds mainly on insects, but will also prey on rodents, snakes and birds when raising their young. These learn to fly about 45 days after hatching but may remain with their parents until fall migration, building up flying skills and fat reserves.
A common sight in summer over the Prairies and the West, Swainson's hawks disappear every autumn. While it was assumed they migrated south, it was long unclear precisely where they went.
A group of researchers that has been studying raptors in northern California for over 40 years has now established exactly where young Swainson's hawks go in winter. The story of their odyssey, summarized in a 30-second clip (scroll down), is both amazing and shocking.
Harnessing the hawks
A Swainson's hawk, with tracking device.
The team harnessed six Swainson's hawks in July, as they were six weeks old and just learning to fly. The clip covers 14 months, until next August – so basically, the first year of flight.
Each harness contains a solar-powered tracker and weighs 20 grams, which represents just 3% of the bird's body weight. To minimize the burden, only females were harnessed: as with most raptors, Swainson's hawk females generally are bigger than males.
The first shock occurs just one month (or about 2.4 seconds) from the start of the clip: the first dot disappears. The first casualty. A fledgling no more than two months old, who never made it further than 20 miles from its nest.
By that time, the remaining five are well on their way, clustering around the U.S.-Mexico border in Texas. Swainson's hawks usually travel at around 40 mph (65 km/h) but can almost double that speed when they're stooping (i.e. dive down, especially when attacking prey).
There's a strong genetic component to migration. As usual, the Germans have nice single word to summarize this complex concept: Zugunruhe ('tsook-n-roowa'), literally: 'migration unrest' (1). It denotes the seasonal urge of migratory animals – especially birds – to get on their way. Zugunruhe exhibits especially as restless behavior around nightfall. The number of nights on which it occurs is apparently higher if the distance to be traveled is longer.
The birds may have the urge to go south, but genetics doesn't tell them the exact route. They have to find that out by trial and error. Hence the circling about by the specimens in this clip: they're getting a sense of where to find food and which direction to go. Their migratory paths will be refined by experience – if they're lucky enough to survive that long.
Each bird flies solo: their paths often strongly diverge, and if they seem to meet up occasionally, that's just an illusion: even when the dots are close together, they can still be dozens if not hundreds of miles apart.
Panama snack stop
The Central American isthmus is a major bird migration corridor
They generally follow the same route as it is the path of least resistance: follow mountain ranges, stay over land. Like most raptors, Swainson's hawks migration paths are land-based: not just so they can roost at night, but mainly to benefit from the thermals and updrafts to keep them aloft. That reduces the need to flap wings, and thus their energy spend – even though the trip will take longer that way.
As this clip demonstrates, the land-migration imperative means the Central American isthmus is a hotspot for bird migration. Indeed, Panama and Costa Rica are favorite destinations for bird watchers, when the season's right. A bit to the north, Veracruz in Mexico is another bird migration hotspot.
It's thought most hawks don't eat at all on migration. This clip shows an exception to that rule: on the way back, one bird takes an extended stopover of a couple of weeks in Panama, probably spending its time there foraging for food.
So, when they finally arrive in northern Argentina, after 6 to 8 weeks' migration, the hawks are pretty famished. Until a few decades ago, they fed on locusts. For their own reasons, local farmers have been getting rid of those. The hawks now concentrate on grasshoppers, and basically anything else that's edible.
For first-time visitors, finding what they need is not easy. Three of the five dots go dark. These birds probably died from starvation. But two birds thrive: they roam the region until winter rears its head in South America, and it's time to head back north again, where summer is getting under way.
Both dots make it back across the border, but unfortunately, right at the end of the clip, one of the surviving two birds expires.
Harsh, but not unusual
This old lady is 27 years old, but still nesting.
While a one-in-six survival rate may seem alarmingly harsh, it's not that unusual. First-year mortality for Swainson's Hawks is between 50% and 80%. Disease, starvation, predators and power lines – to name just a few common causes of death - take out a big number.
Only 10% to 15% of the young 'uns make it past their third or fourth year into adulthood, but from then on, annual survival rates are much better: around 90%. Adult Swainson's Hawks can expect to live into their low teens. There's one documented example of a female Swainson's Hawk in the wild who was at least 27 years old (and still nesting!)
The Californian population of Swainson's Hawks plummeted by about 90% at the end of last century but is now again increasing well. The monitoring project that produced this clip has been going for about four decades but is seeing its funding dry up. Check them out and consider supporting them (see details below).
Migration trajectory of B95, the 'Moonbird'.
Not all migrating birds shun the ocean. Here's an incredible map of an incredible migration path that's even longer than that of the Swainson's hawks.
In February 1995, a red knot (Calidris canutus rufa) in Tierra del Fuego (southern Argentina) was banded with the tag B95. That particular bird, likely born in 1993, was recaptured at least three times and resighted as recently as May 2014, in the Canadian Arctic.
B95 is more commonly known as 'Moonbird', because the length of its annual migration (app. 20,000 miles; 32,000 km) combined with its extreme longevity (if still alive, it's 25-26 years old now) means its total lifetime flight exceeds the distance from the Earth to the Moon.
As many other shorebirds do, the red knot takes the Atlantic Flyway hugging the coastline and crossing to South America via the ocean.
B95 has become the poster bird of conservationists in both North and South America. A book titled Moonbird: A Year on the Wind with the Great Survivor B95 (2012) received numerous awards, B95 has a statue in Mispillion Harbor on Delaware Bay and the City of Rio Grande on Tierra del Fuego has proclaimed B95 its natural ambassador.
Perhaps one day the nameless Swainson's Hawks in this clip, fallen in service of their ancestral instincts – against the odds of human increasing interference – will receive a similar honor.
Strange Maps #965
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(1) 'Zug' is a wonderfully polyvalent German word. It can mean: a train, a chess move, a characteristic, a stroke, a draft (of a plan), a gulp (of air), a drag (from a cigarette), a swig (from a bottle), and more.
Join multiple Tony and Emmy Award-winning actress Judith Light live on Big Think at 2 pm ET on Monday.
From "if-by-whiskey" to the McNamara fallacy, being able to spot logical missteps is an invaluable skill.
- A fallacy is the use of invalid or faulty reasoning in an argument.
- There are two broad types of logical fallacies: formal and informal.
- A formal fallacy describes a flaw in the construction of a deductive argument, while an informal fallacy describes an error in reasoning.
Appeal to privacy<p>When someone behaves in a way that negatively affects (or could affect) others, but then gets upset when others criticize their behavior, they're likely engaging in the appeal to privacy — or "mind your own business" — fallacy. Examples:<br></p><ul><li>Someone who speeds excessively on the highway, considering his driving to be his own business.</li><li>Someone who doesn't see a reason to bathe or wear deodorant, but then boards a packed 10-hour flight.</li></ul><p>Language to watch out for: "You're not the boss of me." "Worry about yourself."</p>
Sunk cost fallacy<p>When someone argues for continuing a course of action despite evidence showing it's a mistake, it's often a sunk cost fallacy. The flawed logic here is something like: "We've already invested so much in this plan, we can't give up now." Examples:<br></p><ul><li>Someone who intentionally overeats at an all-you-can-eat buffet just to get their "money's worth"</li><li>A scientist who won't admit his theory is incorrect because it would be too painful or costly</li></ul><p>Language to watch out for: "We must stay the course." "I've already invested so much...." "We've always done it this way, so we'll keep doing it this way."</p>
If-by-whiskey<p>This fallacy is named after a speech given in 1952 by <a href="https://en.wikipedia.org/wiki/Noah_S._Sweat" target="_blank">Noah S. "Soggy" Sweat, Jr.</a>, a state representative for <a href="https://en.wikipedia.org/wiki/Mississippi" target="_blank">Mississippi</a>, on the subject of whether the state should legalize alcohol. Sweat's argument on prohibition was (to paraphrase):<br></p><p><em>If, by whiskey, you mean the devil's brew that causes so many problems in society, then I'm against it. But if whiskey means the oil of conversation, the philosopher's wine, "</em><em>the stimulating drink that puts the spring in the old gentleman's step on a frosty, crispy morning;" then I am certainly for it.</em></p>
Slippery slope<p>This fallacy involves arguing against a position because you think choosing it would start a chain reaction of bad things, even though there's little evidence to support your claim. Example:<br></p><ul><li>"We can't allow abortion because then society will lose its general respect for life, and it'll become harder to punish people for committing violent acts like murder."</li><li>"We can't legalize gay marriage. If we do, what's next? Allowing people to marry cats and dogs?" (Some people actually made this <a href="https://www.daytondailynews.com/news/national/cats-marrying-dogs-and-five-other-things-same-sex-marriage-won-mean/dLV9jKqkJOWUFZrSBETWkK/" target="_blank">argument</a> before same-sex marriage was legalized in the U.S.)</li></ul><p>Of course, sometimes decisions <em>do </em>start a chain reaction, which could be bad. The slippery slope device only becomes a fallacy when there's no evidence to suggest that chain reaction would actually occur.</p><p>Language to watch out for: "If we do that, then what's next?"</p>
"There is no alternative"<p><span style="background-color: initial;">A modification of the </span><a href="https://en.wikipedia.org/wiki/False_dilemma" target="_blank" style="background-color: initial;">false dilemma</a><span style="background-color: initial;">, this fallacy (often abbreviated to TINA) argues for a specific position because there are no realistic alternatives. Former British Prime Minister Margaret Thatcher used this exact line as a slogan to defend capitalism, and it's still used today to that same end: Sure, capitalism has its problems, but we've seen the horrors that occur when we try anything else, so there is no alternative.</span><br></p><p>Language to watch out for: "If I had a magic wand…" "What <em>else</em> are we going to do?!"</p>
Ad hoc arguments<p>An ad hoc argument isn't really a logical fallacy, but it is a fallacious rhetorical strategy that's common and often hard to spot. It occurs when someone's claim is threatened with counterevidence, so they come up with a rationale to dismiss the counterevidence, hoping to protect their original claim. Ad hoc claims aren't designed to be generalizable. Instead, they're typically invented in the moment. <a href="https://rationalwiki.org/wiki/Ad_hoc" target="_blank">RationalWiki</a> provides an example:<br></p><p style="margin-left: 20px;">Alice: "It is clearly said in the Bible that the Ark was 450 feet long, 75 feet wide and 45 feet high."</p><p style="margin-left: 20px;">Bob: "A purely wooden vessel of that size could not be constructed; the largest real wooden vessels were Chinese treasure ships which required iron hoops to build their keels. Even the <em>Wyoming</em> which was built in 1909 and had iron braces had problems with her hull flexing and opening up and needed constant mechanical pumping to stop her hold flooding."</p><p style="margin-left: 20px;">Alice: "It's possible that God intervened and allowed the Ark to float, and since we don't know what gopher wood is, it is possible that it is a much stronger form of wood than any that comes from a modern tree."</p>
Snow job<p><span style="background-color: initial;">This fallacy occurs when someone doesn't really have a strong argument, so they just throw a bunch of irrelevant facts, numbers, anecdotes and other information at the audience to confuse the issue, making it harder to refute the original claim. Example:</span><br></p><ul><li>A tobacco company spokesperson who is confronted about the health risks of smoking, but then proceeds to show graph after graph depicting many of the other ways people develop cancer, and how cancer metastasizes in the body, etc.</li></ul><p>Watch out for long-winded, data-heavy arguments that seem confusing by design.</p>
McNamara fallacy<p>Named after <a href="https://en.wikipedia.org/wiki/Robert_McNamara" target="_blank">Robert McNamara</a>, the <a href="https://en.wikipedia.org/wiki/United_States_Secretary_of_Defense" target="_blank">U.S. secretary of defense</a> from 1961 to 1968, this fallacy occurs when decisions are made based solely on <em>quantitative metrics or observations,</em> ignoring other factors. It stems from the Vietnam War, in which McNamara sought to develop a formula to measure progress in the war. He decided on bodycount. But this "objective" formula didn't account for other important factors, such as the possibility that the Vietnamese people would never surrender.<br></p><p>You could also imagine this fallacy playing out in a medical situation. Imagine a terminal cancer patient has a tumor, and a certain procedure helps to reduce the size of the tumor, but also causes a lot of pain. Ignoring quality of life would be an example of the McNamara fallacy.</p><p>Language to watch out for: "You can't measure that, so it's not important."</p>
A new study looks at what would happen to human language on a long journey to other star systems.
- A new study proposes that language could change dramatically on long space voyages.
- Spacefaring people might lose the ability to understand the people of Earth.
- This scenario is of particular concern for potential "generation ships".
Generation Ships<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="a1e6445c7168d293a6da3f9600f534a2"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/H2f0Wd3zNj0?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
Many of the most popular apps are about self-improvement.
Emotions are the newest hot commodity, and we can't get enough.