{"id":2248,"date":"2019-10-25T00:08:53","date_gmt":"2019-10-25T00:08:53","guid":{"rendered":"http:\/\/wordpress.viu.ca\/biol325\/?p=2248"},"modified":"2019-12-04T19:11:21","modified_gmt":"2019-12-04T19:11:21","slug":"shakespeares-greatest-tragedy-the-invasive-european-starling","status":"publish","type":"post","link":"https:\/\/wordpress.viu.ca\/biol325\/2019\/10\/25\/shakespeares-greatest-tragedy-the-invasive-european-starling\/","title":{"rendered":"Shakespeare’s Greatest Tragedy: The Invasive European Starling"},"content":{"rendered":"\n

The year\nwas 1890, Europeans flocked<\/em>\nto the big apple for a chance to begin a better life in the new world. Bringing\nwith them shoes, hats, smallpox,\nand the European Starling. <\/p>\n\n\n\n

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As the legend has it, an avid Shakespeare fan, and lover of birds, by the name of Eugene Schieffelin introduced 60 Starlings to Central Park New York City with the dignified intent of introducing all species of bird mentioned in Shakespeare’s writings (Zielinski 2011<\/a>). The Nightingales and the Skylarks he had previously released had all died off, so he could only cross his fingers and hope that the Starlings would breed (Zielinski 2011<\/a>)! And indeed, breed they did. Today, 129 years later, North America is home to over 200 million Starling ranging geographically from Alaska all the way down to central America (Cabe 1993<\/a>). Thanks Eugene!<\/p>\n\n\n\n

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Figure 1: The North American geographical distribution of the European Starling. There are actually less European Starling in Europe than in North America at this point as their European numbers have been declining due to fewer grassland invertebrates being available as a food source (Inger et al. 2015<\/a>).<\/figcaption><\/figure><\/div>\n\n\n\n
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Meet The European Starling<\/h2>\n\n\n\n

Starling\u2019s are moderate sized passerine bird that is very similar in size to an American Robin; the average European Starling has a 16 inch wing span, is about 8 and a half inches long, and weighs in at 82 grams (Sibley 2000<\/a>). If you are looking to spot a European Starling the first thing you need to know is that they have differing plumages throughout their life.<\/p>\n\n\n\n

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In breeding season (between spring and summer) the European Starling is very striking. A mysterious colour palette of iridescent deep purples, blues, and greens accompanied by a distinguishable yellow bill combine to give this bird a sinister beauty \u2014 sinister because they are horribly invasive, and beauty because they are quite beautiful (Sialis 2016<\/a>; The Cornell Lab… 2019<\/a>). In non-breeding season the bill will usually be black but will turn yellow as breeding season grows near and the colours of the plumage are the same. However, you will be able to see cream coloured spots speckled about their body. This is because when their feathers are first grown they have cream tips (The Cornell Lab… 2019<\/a>).  <\/p>\n\n\n\n

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Figure 2: The differing plumage of European Starlings. Breeding adult (left), Non-breeding adult (middle), juvenile (right) (Photos by Dan Vickers – left, Ryan Schain – middle, and Walter Marcisz – right<\/a>)<\/figcaption><\/figure>\n\n\n\n

By breeding season all these spots will be gone, but not by molting as you might have suspected. Instead, the spots disappear by simply being worn off  (Sibley 2016<\/a>). The feathers do not continue to wear down past the tips as the rest of the feather contains melanin (a dark pigment that is resistant to wear). Finally, in juvenile plumage the Starling will be a pale brown colour with no spots at all and a black bill (Sibley 2016<\/a>).<\/p>\n\n\n\n

For further identification traits it is helpful to know that they tend to fly in flocks \u2014 known as murmurations, but more on that below\u2014 and their flight pattern is a sustainable powered flight with very little gliding (Sialis 2016<\/a>). A wise Frenchmen once told me that the European Starling is easily identifiable by its short tail and its pointed wing tips (2019 advice from Eric Demers)\u2026 Moments later he confused a Raven for an Eagle, but that’s beside the point.<\/p>\n\n\n\n

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Figure 4: From a distance the European Starling could be confused with other bird species such as the red winged blackbird (left). However, note the significant difference in wing and tail shape between the two birds (Photos by Ian Neilson – left<\/a>, and Patricia Ware – right<\/a>)<\/figcaption><\/figure>\n\n\n\n

European Starling\u2019s don\u2019t like to eat alone, they primarily feed on insects and prefer to forage on the ground but may also feed in flight (Audubon 2019<\/a>). Skull and jaw muscle adaptations have been noted to allow the bird to spring its mouth open to help with probing and feeding. Upon inserting their bill into the soil the European Starling’s strong jaw muscles allow it to spring open and widen the hole (The Cornell Lab… 2019<\/a>). Furthermore, their narrow skull makes it possible for the eye to move forward allowing the European Starling to peer into the hole and identify any food items (Sialis 2016<\/a>). <\/p>\n\n\n\n

While the European Starling seems to prefer feeding on insects, they are very versatile and adaptive feeders; a skill that has no doubt helped them become so established world wide (Sialis 2016;<\/a> Audubon 2019;<\/a> The Cornell Lab… 2019<\/a>). They have been documented to eat fruits, insects, spiders, snails, seeds, and even frogs and lizards (Sialis 2016<\/a> ). Considering just how far and wide this bird has travelled it should come as no surprise that they eat such a cultured diet. <\/p>\n\n\n\n

Because of this diet the European Starling has been referred to as a pest by many. These guys might just come along and dig up your newly planted seeds, or maybe they’ve decided to eat your grapes right off the vine. Either way, when a large group of Starling come around your crops you could find yourself faced with a lot of damage. A 1996 study estimated that European Starlings caused 800 million dollars of agricultural damage per year in the United States alone (Pimental et al. 2000<\/a>).<\/p>\n\n\n\n

On top of being an agricultural pest, the European Starling is also a pest to native bird species. European Starlings tend to be particular about their nesting sites, preferring to nest in pre-established cavities (The Cornell Lab… 2019<\/a>). Well what happens if they like the nesting nook of another bird? Unfortunately, they have been known to evict many native species from their nesting sites, including: Wood ducks, Woodpeckers, Screech Owls, Kestrel, and undoubtedly many more (Sialis 2016<\/a>). European Starlings even tend to torment their kin, up to one third of a European Starling\u2019s first broods are killed by fellow Starlings dumping eggs out of the nest (Sialis 2016<\/a>).<\/p>\n\n\n\n

While we deem the Starling to be a bit of a pest it seems that they enjoy being around us as they are most often found in disturbed habitat such as suburbs, fields, and farms and are rarely seen in extensive forests. Some European Starling may migrate for a warmer climate in the winter, yet others choose not too (Sialis 2016<\/a>). As can be seen in figure 1<\/em>, they are found year-round in almost all of North America.<\/p>\n\n\n\n

The European Starling has been known to dabble in vocal mimicry and is classified as an intermediate mimic meaning it does mimic but predominately uses its own vocalizations (Hindmarsh 1984<\/a>). While the European Starling can mimic, their repertoire is limited to songs and sounds that are simple in structure but they can still learn dozens of different songs (Hindmarsh 1984<\/a>). As with many mimics, these mimicked vocalizations are used as a breeding strategy by males for attracting a female. However, both males and females can mimic and are known to sing outside of breeding season (Sialis 2016<\/a>).<\/p>\n\n\n\n

Some standard sounds you may hear in a European Starling Song. Mostly whistles and mechanical sounding clicks (Audio from Whatbird.com<\/a>)<\/figcaption><\/figure>\n\n\n\n
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