{"id":2453,"date":"2019-10-31T02:10:32","date_gmt":"2019-10-31T02:10:32","guid":{"rendered":"http:\/\/wordpress.viu.ca\/biol325\/?p=2453"},"modified":"2019-10-31T02:10:34","modified_gmt":"2019-10-31T02:10:34","slug":"b-c-s-steller-bird-cyanocitta-stelleri","status":"publish","type":"post","link":"https:\/\/wordpress.viu.ca\/biol325\/2019\/10\/31\/b-c-s-steller-bird-cyanocitta-stelleri\/","title":{"rendered":"B.C.’s Steller Bird: Cyanocitta stelleri"},"content":{"rendered":"\n

The Steller’s Jay (Cyanocitta stelleri) <\/em><\/h2>\n\n\n\n
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A Steller’s jay (Cyanocitta stelleri<\/em>) (left) compared to a blue jay (Cyanocitta<\/em> cristata<\/em>) (right). (Steller’s jay photo by Genevieve van der Voort, blue jay photo courtesy of Samuelle Simard-Proven\u00e7al).<\/figcaption><\/figure><\/div>\n\n\n\n

While sometimes mistakenly called \u201cblue jays\u201d, Steller\u2019s jays (Cyanocitta stelleri<\/em>) are a unique species of their own. Steller\u2019s jays are in the same genus as blue jays, Cyanocitta<\/em>, and are members of the family, Corvidae, however, the two species rarely have overlapping ranges, with Steller\u2019s jays occurring in western North America and blue jays in the east (Audubon<\/a>).
Steller\u2019s jays are a long-lived species, with the oldest wild Steller\u2019s jay being 16 (All About Birds<\/a>). Steller\u2019s jays acquired their name from the German naturalist Georg Wilhelm Steller, and share this namesake with several other familiar species, such as Steller\u2019s sea lion (Eumetopias jubatus<\/em>) and Steller\u2019s eagle (Haliaeetus<\/em>\u00a0pelagicus<\/em>). Steller described the jays while stopped on Kayak Island, Alaska during his 1741 voyage. The species was later given its name by Johann Friedrich Gmelin in 1788 (Birds of North America<\/a>). In 1987 the Steller\u2019s Jay was voted by the public to be B.C.\u2019s provincial bird, beating the peregrine falcon (Falco peregrinus<\/em>) by around 2,000 votes (Yearwood-Lee, 2006<\/a>). <\/p>\n\n\n\n

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Description<\/h3>\n\n\n\n
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A Steller’s jay perched on a branch. Note the streaked triangular crest on the top of the head. (Photo by Doug Mosher<\/a>).<\/figcaption><\/figure><\/div>\n\n\n\n

Steller\u2019s jays are distinguished by their stark colours, mainly blues and black, and by the triangle-shaped crest of feathers extending from the tops of their heads. Younger birds will be a duller grey compared to the dark black found on adults (Sibley, 2000<\/a>). <\/p>\n\n\n\n

It is not possible to identify the sex of the bird based on visual identifiers, especially from a distance (Sibley, 2000<\/a>). Their striking blue colours are a result of light reflecting off air and keratin found in the feathers. The production of these structural colours may serve as an indication of a bird\u2019s quality to potential mates (Zirpoli et al<\/em>., 2013<\/a>). <\/p>\n\n\n\n

Subspecies<\/h4>\n\n\n\n

There have been 16 described subspecies of Steller\u2019s Jay (All About Birds<\/a>), with at least 13 occurring in North America (Wiebe, 1995<\/a>). Different subspecies will have different colours present and small differences in sizes. For example, Cyanocitta stelleri ridgwayi,<\/em> a subspecies found in Chiapas and west Guatemala, have more blue than Northern subspecies (Madge and Burn, 1994<\/a>)<\/p>\n\n\n\n

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Cyanocitta stelleri ridgwayi<\/em>, a subspecies of Steller’s jay found in Central America. (Photo by Francisco Herrera<\/a>). <\/figcaption><\/figure><\/div>\n\n\n\n

There are three to four subspecies found in B.C.; Cyanocitta stelleri stelleri<\/em>, C. s. carlottae<\/em>, C. s. annectens<\/em> and C. s. paralia<\/em>. The C. s. paralia<\/em> populations in B.C. are possibly mixes between C. s. stelleri,<\/em> C. s. annectens<\/em> and C. s. paralia<\/em>. C. s. paralia<\/em> has also sometimes been grouped with C. s. stelleri<\/em> (Wiebe, 1995)<\/a>. <\/p>\n\n\n\n

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Different subspecies of Steller\u2019s jay are found in B.C. in depending on the region. Note the differences in crest streaking and the supercilium (eyebrow spot). (Interior jay photo<\/a>, coastal jay photo<\/a>, and Haida Gwaii jay photo<\/a> from iNaturalist ).
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The coastal B.C. subspecies (C. s. stelleri<\/em>), have medium to dark blue streaks on their crests, with some on Vancouver Island being lighter blue.<\/p>\n\n\n\n

Interior subspecies (C. s. annectens<\/em> and C. s. paralia<\/em>): have breast feathers that are lighter blue and a greyish back. The majority have light blue streaks on their crests and a white spot above their eye. C. s. paralia<\/em> look similar to C. s. annectens<\/em> but may be slightly smaller and darker.<\/p>\n\n\n\n

The Haida Gwaii are home to an endemic subspecies, C. s. carlotte<\/em>. Most birds are lacking coloured streaks in their crest and this subspecies is relatively darker and larger than the other B.C. subspecies (Wiebe, 1995<\/a>).<\/p>\n\n\n\n

To further confuse the things, not only can subspecies overlap (Wiebe, 1995<\/a>), Steller\u2019s jay and blue jay hybrids have been observed in Colorado, where the species\u2019 ranges meet (All About Birds<\/a>). The behaviour of these hybrids was observed to match that of Steller\u2019s jay when feeding, and the hybrids were observed using both Steller\u2019s jay and blue jay calls (Williams and Wheat, 1971<\/a>). <\/p>\n\n\n\n

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A hybrid Steller’s jay and blue jay with a peanut (Williams and Wheat, 1971<\/a>). <\/figcaption><\/figure><\/div>\n\n\n\n
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Habitat and Range<\/h3>\n\n\n\n

Steller\u2019s jays can be found in, pine, spruce, fir, and mixed oak forests (Audubon<\/a>). They tend to reside higher in trees and in small groups (Sibley, 2000<\/a>). When the jays are not nesting, they may venture into other habitats, such as orchards and suburbs, and are a striking visitor at bird feeders. While their ranges are usually fixed and they are a non-migratory species, during the winter they may migrate to lower elevations, possibly depending on food availability (Audubon<\/a>). <\/p>\n\n\n\n

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A map of North America showing the distribution of Steller’s jay (All About Birds<\/a>)<\/figcaption><\/figure>\n\n\n\n

Steller\u2019s Jay populations are considered stable (All About Birds<\/a>). However, Environment Canada has listed the species as a \u201cpriority species\u201d for assessing and maintaining their populations in coastal B.C., especially C. s. carlotte<\/em>, the subspecies endemic to Haida Gwaii (Canadian Wildlife Service, 2013<\/a>). <\/p>\n\n\n\n

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Sounds<\/h3>\n\n\n\n

Steller\u2019s jays are vocal and make a variety of calls, such as a harsh \u201cshaaaaar<\/em>\u201d (or “wah<\/em>“), or multiple and rapid \u201cshek shek shek<\/em>\u201d (or “weh<\/em>“) noises (Sibley, 2000<\/a>). Many of their calls are used in communication, especially when interacting with other jays during courtship or confrontation (All About Birds<\/a>). <\/p>\n\n\n\n

Steller’s jay’s “wah<\/em>” calls followed by their “wek<\/em>” calls. (Audio from Kelly Perry<\/a>)<\/figcaption><\/figure>\n\n\n\n

These two calls may also function as alarm signals to other jays (Billings et al<\/em>., 2017<\/a>). \u201cWah<\/em>\u201d calls have been observed when a group of jays were seen mobbing a Cooper\u2019s hawk (Accipiter cooperii<\/em>) and may possibly be used to confuse the predator during the mobbing (Ficken, 1989<\/a>). Groups of Steller\u2019s jays will alter the number of \u201cwah<\/em>\u201d and \u201cwek<\/em>\u201d calls in the presence of different potential predators. For example, when presented with the audio or visual cues of a well-known predator, Northern goshawks (Accipiter gentilis<\/em>), Steller\u2019s jays produced more alarm calls than when presented with a less-threatening predator, Northern pygmy owls (Glaucidium californicum<\/em>) (Billings et al<\/em>., 2017<\/a>). <\/p>\n\n\n\n

Steller\u2019s jays are known to mimic many other species, including red-tailed hawks (Buteo jamaicensis<\/em>), northern flickers (Colaptes auratus<\/em>), northern goshawks, white-breasted nuthatches (Sitta carolinensis<\/em>), and squirrels. They have also mimicked mechanical noises in their environment, such as sprinklers (All About Birds<\/a>). There are different theories as to why jays mimic predatory species. One possibility is that they may be able to exclude other birds from feeding by scaring them off. Another idea is that these calls are made by the group to serve as alarm calls. When the call of a red-tailed hawk was played to a group of feeding Steller\u2019s jays, the groups reacted by mimicking the call and then fleeing the feeding area (Billings <\/a>et al<\/a><\/em>., 2017<\/a>). <\/p>\n\n\n\n

A Steller’s jay mimicking the call of a red-tailed hawk (Audio from Audubon<\/a>)<\/figcaption><\/figure>\n\n\n\n
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Nesting<\/h3>\n\n\n\n
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Baby Steller’s jays will wait to be fed by their parents. While not as striking as the adults, note their characteristic blue and black colours forming. (Photo by Sarvey Wildlife <\/a>)<\/figcaption><\/figure><\/div>\n\n\n\n

Steller\u2019s jays will form long-term pairs that work together to build their nests, feed nestlings, and defend territory (Overeem <\/a>et al<\/a><\/em>., 2014<\/a>). Their nests are built usually in conifers. It takes approximately 16 days each to build a nest and incubate their young. Their nests are made of twigs, leaves and other plant material or animal hair stuck together with mud. Females usually have one brood per year, with 2-6 eggs per clutch. The colour of the eggs can range from bluish-green to spotted brown or olive (All About Birds<\/a>). <\/p>\n\n\n\n

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Diet<\/h3>\n\n\n\n

Steller\u2019s jays will forage year-round and are known to eat a wide variety of foods, such as nuts, seeds, insects, berries, eggs, garbage, suet, and smaller animals (All About Birds<\/a>, Audubon<\/a>). During periods of prolonged snow and cold in Arizona, there have been observations of Steller\u2019s jays capturing and eating an adult Pygmy Nuthatch (Sitta pygmaea<\/em>) and adult Grey-headed Juncos (Junco hyemalis caniceps<\/em>) (Carothers <\/a>et al<\/a><\/em>., 1972<\/a>). <\/p>\n\n\n\n

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Mimic marbled murrelet eggs used by Gabriel and Golightly (2017) (left), and a Steller’s jay next to the mimic eggs in the field (right) (Photos by Richard Golightly<\/a>) <\/figcaption><\/figure><\/div>\n\n\n\n

As previously mentioned, Steller\u2019s jays also consume the eggs of other birds. An example of a species they prey upon is the endangered marbled murrelet (Brachyramphus marmoratus<\/em>). These birds nest inland in the canopy of conifer trees. Predation by Corvids (e.g<\/em>. crows, ravens, jays) is thought to one of the factors affecting the survival of this species (H\u00e9bert and Golightly, 2007<\/a>). Gabriel and Golightly (2014<\/a>) showed that wild Steller\u2019s jays can be taught to avoid marbled murrelets eggs when presented with mimic eggs that contain a low, non-toxic level of emetic carbachol, a substance that induces retching and vomiting. The Steller\u2019s jays learned to associate these reactions with the eggs, and predation of mimic eggs was reduced by 37% in the field. <\/p>\n\n\n\n

Caching<\/h3>\n\n\n\n

Many species of jays will cache their food, meaning they will store a food item and return later to consume it. Steller\u2019s jays will store foods such as acorns and other seeds by burying them (Kalinowski <\/a>et al<\/a><\/em>., 2015<\/a>). These caches may be accessed during the winter when food is scarce or for short term use soon after the item has been cached (Rockwell <\/a>et al<\/a><\/em>., 2013<\/a>). <\/p>\n\n\n\n

Steller\u2019s jays are also known to take advantage of other caching species of bird. They have been seen robbing the caches of Canada jays (Perisoreus canadensis<\/em>) and Clark\u2019s nutcrackers (Nucifraga columbiana<\/em>) (Burnell and Tomback, 1985<\/a>). The behaviour of these two species has been seen to change when in the presence of a Steller\u2019s jay, often by delaying caching (Burnell and Tomback, 1985<\/a>). Similarly, a study by Kalinowshi et al<\/em>. (2015<\/a>) observed how Steller\u2019s jays alter their own behaviour in the presence of other Steller\u2019s jays, by travelling and hiding their caches from mates (when not breeding) and travelling even farther when around non-mate Steller\u2019s jays. \u00a0<\/p>\n\n\n\n

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