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The British may have lost North America but their native house sparrows have successfully colonized the continent.

The British lost North America but English house sparrows have colonized the continent.

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It seems to happen once each century. In 1775 the Redcoats showed up in Boston, the Beatles made a big splash about 200 years later in 1964, and in the sweet-spot in-between the House Sparrows (Passer domestics) arrived.
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It’s difficult to believe, given current controversies and political grandstanding, but for a long time America had a very open-door immigration policy that allowed almost anyone—human and non-human—hassle-free entry. For example, no one batted an eye when my paternal ancestors washed up here after being kicked out of Scotland during the Highland Clearance to make room for sheep… but I digress. In the 1850s, when Brooklyn Institute Director Nicholas Pike purchased 8 pairs of house sparrows from England he didn’t have to sneak the birds past a Customs agent—the Animal and Plant Health Inspection Service (APHIS) hadn’t been created yet and wouldn’t be for over 100 years. Nor did Pike need permission from the New York Department of Environmental Conservation to release the birds. It didn’t exist.
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Introducing these Old World sparrows to North America was not done on a whim. Some sources suggest the birds were imported to control a serious canker-worm (Alsophila pometaria or Paleacrita vernata) infestation threatening New York City’s trees—a somewhat misguided notion since house sparrows are granivores (seed-eaters), not insectivores, although they do feed insects to their nestlings.  Pike reportedly paid $200 for the pairs’ passage across the Atlantic, which may not sound like much but according to one relative-value calculator it’s equivalent to $5,000 today.
.feeding the sparrows
Like many immigrants before them those first settlers didn’t do all that well in their new home. Not dissuaded, Pike purchased another 25 pairs the following year and released them along the East River. This cohort proved hardier, or perhaps more adaptable. Another 100 pairs were ordered in 1853 and released at the Greenwood Cemetery, Central Park, Union Square Park, and Madison Square Park. Americans have a history of Anglophilia so it should come as no surprise that soon the former colonies were all a-twitter about these chatty, cheerfully social birds.
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male house sparrow by Eric Bégin, CCLHouse sparrows aren’t closely related to native North American sparrows and you can see it in their physique—they’re a bit heavier, with a deeper chest, a more rounded head, shorter tail, and a less delicate bill. Six inches (15 cm) long from beak to tail-tip, and weighing in at about 1.4 oz (40 g), the male house sparrow cuts a dashing but not flashy figure; he’s British, don’t forget, and all business. Bright blues, greens, and yellows are not his cup of tea; rather, he wears a neutral palette of black, gray, and chestnut, with a touch of white to sharpen up the entire female house sparrow2ensemble. Female fashion preferences are appropriately tweedy: tawny-brown with darker striping on top, oatmeal-tan or gray below. More Anthony Hopkins and Emma Thompson than David Bowie and Amy Winehouse, nonetheless, house sparrows were a trending novelty that went viral.
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Entrepreneurs recognized a market opportunity and became breeders.  Citizens in Maine, Connecticut, Rhode Island, and Pennsylvania all followed Pike’s lead, and by 1870 this pioneering species had spread south to Texas, north to Montreal, and past the Mississippi River to Iowa. A West Coast population was established with releases in California (1871-1872) and Utah (1873-1874), and in the subsequent decade house sparrows expanded their range from less than 1,200 mi2 to over 500,000 mi2. By the turn of the 20th century the space between eastern and western fronts had nearly filled.
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Why have house sparrows thrived while other species—including some natives—have failed? Here are the keys to making it in America:
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Get lucky.  House sparrows couldn’t have wished for better timing to facilitate their successful acclimation. Steam and internal combustion engines were coming on strong but horses and cattle were still the primary means of facilitated transportation. Working herbivores need more calories than grass and hay alone can provide so corn, barley, oats, wheat, and rice are common additions to the diet. Hoof-stock “exhaust” has a fair amount of undigested “fuel” and resilient city sparrows weren’t picky about where they got their vittles. Additionally, urbanites raised livestock and poultry and a small bird could easily slip in and out of pens and stables to pinch a bite or two. Enterprising sparrows even hitched rides on those new-fangled locomotives and their boxcars filled with grain.
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Grow up fast, breed early and often.  House sparrows eggs hatch after 10-16 days of incubation, nestlings fledge at 14-15 days old, are independent 7-10 days later. One study suggests they may reach sexual maturity as early as 4 months of age—time to find a mate and get busy! Females produce 2-5 clutches of 3-7 chicks per breeding season; that’s an average of 20 chicks per season, per breeding pair. Do the math and there’s your answer.
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Stand up for yourself and your kin.  House sparrows will form loose nesting colonies, are strongly territorial, and will aggressively defend nest sites and feeders. They’ll attack both intruders and potential intruders, and have been known to destroy the eggs and nestlings of competitor species.
. Be smart, adaptable, and adventurous.  Many bird species follow a strict set of guidelines when it comes to choosing where to raise a family.  Sparrows, on the other hand, sparrow nest by gingiber, CCL are willing to at least consider nearly any property when scouting for real estate. You’ll find them nesting in a wide range of locations—nest boxes and tree cavities, of course, but also signs, architectural features, drain pipes, dryer vents, and anywhere else that offers a large enough entrance.  When a potential nesting site has been identified they’ll use every means at their disposal to make it work.  They can even learn how to trip automated door sensors to access food and shelter from the elements and predators. When young house sparrows are old enough to leave the nest they’ll readily disperse 5 miles or more to find new feeding and nesting areas and quickly learn how to claim and exploit available resources.
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Have friends in high places. If you’re a wild thing, having H. sapiens on your side is the equivalent of a royal patronage. In the mid-19th century people trapped house sparrows from one place and released them into new territory cleared of predators and outfitted with nesting boxes.  That, my friends, is what’s called “choosing sides.” Is it any wonder house sparrows are now found in all 48 contiguous states and Hawaii’i (where they were introduced from New Zealand in 1871)? The kindness of human strangers has also allowed P. domesticus to claim much of Canada, all of Central America, most of South America, southern Africa, and eastern Australia.
dark green = natural range light green = introduced range

dark green = natural range     light green = introduced range

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I’m sure you can guess how this story goes, though. It’s been played out countless times in the media—print, broadcast, and social.  First they love you, then they love to hate you.  Americans adore a winner but as any reality TV star can attest, get too successful and fans will take equal pleasure in watching, sometimes facilitating, your fall from grace.
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Even as the house sparrow fad continued to grow, some conservation-minded folk had begun to notice the immigrants were not assimilating as hoped, or following local customs and expectations. Before long, civic leaders had deemed house sparrow nests “unsightly.” Their droppings were blamed for “besmirched” buildings and sidewalks.  They were tagged as thieves who pilfered valuable grain from honest, hard-working farmers. Worse yet, the foreigners were observed being downright inhospitable to the native avian community, including valuable insect-eaters. The nerve of those ungrateful little upstarts!!
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sparrow trap (Albert F. Siepert, Project Gutenberg License)Guides for trapping, shooting, and poisoning the birds were distributed free of charge. By 1883, state legislators in Indiana had declared the house sparrow an outlaw who should be killed on sight. Five years later, Illinois and Michigan had established a small bounty on “English” sparrows and children scrambled to exchange dead birds for cash to buy candy.
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Never mind the fact that human development was having at least as great an impact on native bird species as the house sparrow we had intentionally loosed upon the landscape. Forget that the effects of trapping and poisoning are rarely limited to the intended target species. Ignore the lack of conservation legislation that allowed “market hunting” to bring dozens of wild bird populations to the brink of extinction. The public was frightened and angry about the changes in their communities wrought by industrialization and human migration. Scapegoats were needed to pay the piper for society’s sins and transgressions.
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Many individual house sparrow were killed but despite the all-in extermination effort the species continued to thrive. While no longer hunted for bounties in the US., the bad PR stuck like glue—to this day they are generally resented or reviled. Unlike migratory species house sparrows are not protected in the U.S. and, in fact, the population has declined somewhat.
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save-sparrowFollowing the tried and true media script, the house sparrow is experiencing a rebound in popularity, at least in its native range. This is due to precipitous population declines in England, where this native species has been “red-listed,” Europe, Scandinavia, and India. The problem seems to be a lack of available food for their young—nestlings need the higher level of protein insects provide, only later changing to a grain-based diet. As Rachel Carson pointed out decades ago, our pesticide arms race takes a toll on many of the creatures we enjoy having around. Over the past 10-15 years, “Save Sparrows” campaigns have encouraged home-owners to decrease or eliminate insecticide use, choosing insect-attracting plants, and intentionally increasing nesting sites.
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I’ve yet to see anything in the scientific literature proposing North American as a possible source of imported house sparrows to repopulate their original range but there’s a nice full-circle appeal to that storyline.  Maybe you can go home again.
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love-earthThis blog, like so many activities that foster support and appreciation of the natural world, is a labor of love. If you’ve enjoyed learning about the creatures who share our built environment, consider becoming an NDN Benefactor with a donation of any amount you’re inspired to give. If you’d like to find a little Next-Door Nature surprise in your inbox just click the Subscribe!  button in the upper right-hand corner of this page and receive notifications of new posts!
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© 2015 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work  but please ask). Thanks to these photographers for making their work available through a Creative Commons license (CCL) or Project Guttenberg License (PGL) (from top to bottom): Martha de Jong-Lantink, CCL (birds on a branch); Harper & Brothers, PGL (feeding the sparrows); Eric Bégin, CCL (male HOSP); Phil McIver, CCL (female HOSP); gingiber, CCL (HOSP nest); Cactus26, CCL (HOSP distribution map); Albert F. Siepert, PGL (sparrow trap).

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next-door nature, mountain lion, cougar, dispersal, Midwest

Cougars are one of several predator species returning to historic ranges, even when they include highly developed areas (Photo: Wayne Dumbleton, Creative Commons license)

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Midwesterners are welcoming the return of some long-absent natives.

On second thought, “welcoming” is probably an overstatement… because just as in the famous biblical parable, not everyone is thrilled about this reunion.

A rigorous statistical study to be published in an upcoming issue of the Journal of Wildlife Management confirms the presence of 178 cougars (Puma concolor) in the Midwestern U.S. states of Missouri (10), Nebraska (67), North Dakota (31), Oklahoma (12), South Dakota (11), and Texas (12). Single incident reports were documented in Arkansas, Illinois, Iowa, Kansas, Louisiana, Michigan, Minnesota, and Wisconsin.

next-door nature, cougar, mountain lion, historic photo, market huntingOnce found throughout North America, from the Canadian Yukon south to the Chilean Patagonia and all 48 contiguous United States, cougar populations dropped precipitously over most of their historic range following European colonization of the continent. The 19th and early 20th centuries, in particular, were hard times for all wild predators. Eradication programs aimed at protecting livestock interests were common. Bounties for cougar pelts, combined with sport hunting and a reduced prey base, lead to extirpation of the species east of the Rockies, with the exception of a small subspecies population in Florida (the Florida panther, Puma concolor corryi).

You’ve heard of a coat of many colors? How about a cat of many names? Cougars are almost interchangeably known as mountain lions and pumas, but regional variants include catamount, panther, painter, ghost cat, screamer… and that’s just the English nomenclature.

The cougar has had more than it’s share of scientific names, too. Originally considered the largest member of the Felis clan, a genus that includes both the domestic cat (F. catus) and the somewhat larger jungle cat (F. chaus), in 1993 taxonomists created a new Puma group based on similar genetic structure and composed of two members—P. concolor and P. yagouaroundi, the much smaller jaguarondi, found in Central and South America. Another homecoming of sorts, I guess you could say, although whether the members are happy about their new blended family is anyone’s guess.

As the forth largest of all the world’s cats, adult cougars reach shoulder heights of between 24-35 inches (60-90 cm), nose-to-tail lengths of between 6.5-8 ft (2-2.4 m, females and males, respectively), and average weights of 100-150 lbs (42-62 kg; females and males, respectively).  It’s interesting to note that the closer a cougar lives to the equator the smaller it will likely be; the largest cougars are those found closest to the poles.

The species gets its name from the Latin word for “plain” or “one color” and that’s generally true for individual animals (as long as you ignore the lighter belly, throat and chin). At the population level there’s significant color variation, from golden to silvery-grey or even coppery-red. Cougar kittens don’t start out concolor—they are spotted with ringed tails but these markings fade as the youngsters mature.

next-door nature, cougar, mountain lion, dispersal, historic range, midwestAdult cougars have a sleek but muscular physique and are able climbers and strong swimmers, with exceptional leaping and powerful sprinting skills. Despite their speed, these cats are typically ambush predators that quietly stalk and then, if possible, drop silently down onto prey from above, breaking the neck or delivering a suffocating bite.

Cougars are obligate carnivores, which means to survive most of their calories must come from meat. What’s less important is whether the main course is mouse, squirrel, rabbit or raccoon, mutton, venison or veal. This failure to discriminate between wild game and domestic livestock has resulted in a long and bitter feud with ranchers that continues to this day.

The 1960s, however, were witness to a sea change in American attitudes toward the environment in general and predators specifically—at least in the urban and suburban areas that were rapidly becoming home to a majority of citizens. Public pressure to change management policies created greater legal protection for cougars and their numbers began to increase. Over subsequent decades, pressure to disperse has obviously increased as well, as western cougar habitat reaches carrying capacity.

Which brings us right back to where we started, with cougars recolonizing the center of the continent. They use what researchers call a “stepping stone” pattern. Young animals say goodbye to Mom (male cougars are absentee dads) and go looking for adventure. Travel the highways and byways, stop at an interesting locale, scout out dating and dining options then move along. Sometimes quite far along… as was the case with a male cougar who made it to Connecticut before being hit and killed by a vehicle.  Leaving home is what most young mammals, including humans, are programmed to do. I’m as good an example as any, having dispersed from Missouri at 21 to explore all three North American coasts and beyond.

next-door nature, cougar, mountain lion, dispersal, midwestCougars may have returned to their old stomping grounds but don’t expect fireworks or any other hoopla. As a native who left the area and has returned many times (although never to stay) I can assure you this homecoming will be a low-key affair.

We Midwesterners don’t like to call attention to ourselves, you know.

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© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work. Just ask first.). Thanks to these photographers for making their work available through a Creative Commons license:  Wayne Dumbleton (cover); USFWS/Public Domain (historic photo of a market cougar hunter); Anthonut (profile); Susan Shepard (climbing down); NaturesFan1226 (sharpening claws).

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