These birds are fairly small, being around the same size as the widespread American goldfinch. In both sexes, total length can range from 11–14 cm (4.3–5.5 in), with a wingspan of 18–22 cm (7.1–8.7 in) and weight of 12–18 g (0.42–0.63 oz).
Adults are brown on the upperparts and pale on the underparts, with heavy streaking throughout. They have short forked tails. Their bills are conical like most finches but are more elongated and slender than those of other co-occurring finches. Variably, pine siskins have yellow patches on their wings and tails, which may also consist of white streaks on the wings. Although they can be confused by the more inexperienced for other finches or even American sparrows, pine siskins are distinguished by their heavy streaking, relatively slender bills, notched tail, yellow or whitish patches on the wings and smallish size.
Separation from European siskin
Pine siskin in its typical morph is a drab bird, whereas European siskin (a bird the species does not naturally co-exist with), in many plumages, is much brighter. Adult male European siskins are bright green and yellow with a black cap, and an unstreaked throat and breast; pine siskin does not have a corresponding bright plumage. Adult female European siskins also usually have green and yellow plumage tones: for example, yellow in the supercilium and on the sides of the breast, green tones in the mantle and yellow in the rump. Adult pine siskins of the typical morph do not have green and yellow tones, although juveniles can have a yellowish-buff wash on their underparts and buff-toned wingbars, for a short period prior to their autumn migration. The ground colour of the underparts of European siskin is normally pure white, whereas on pine siskin it is usually a dirtier colour. In female and juvenile European siskin, the centre of the belly and lower breast are often largely or entirely unstreaked, whereas in most pine siskins the streaking extends across the whole of the underparts. The wingbars of European siskin are broad and yellow (with the tips white) whereas they are normally narrower and buffish-white in pine siskin, contrasting with the bright yellow flash at the base of the primaries. Pine siskins have a longer bill, usually with a straight culmen, compare with a short bill in European siskin, with a decurved culmen. There is a green morph of pine siskin, closer in appearance to European siskin; these birds make up only 1% of the population. These are closer in appearance to female European siskin, but differ in that they have a yellow-wash on the undertail-coverts (white on European siskin), no yellow in the supercilium, reduced underparts streaking, and much yellow at the base of the tail and remiges; there may also be a difference in the extent of yellow in the underparts but this needs further study.
Distribution and habitat
Their breeding range spreads across almost the entirety of Canada, Alaska and, to a more variable degree, across the western mountains and northern parts of the United States. As their name indicates, the species occurs mostly as a breeder in open conifer forests. Northern pine forests supports the majority of the species breeding population. However, stands of ornamental conifers or deciduous trees may support nesting birds in partially developed parks, cemeteries, and suburban woodlands. While they favor feeding in open forest canopies where cone seeds are abundant, they'll forage in habitats as diverse as deciduous forests and thickets, meadows, grasslands, weedy fields, roadsides, chaparral, and backyard gardens and lawns. They flock to backyard feeders offering small seeds. Mineral deposits can lure them to otherwise unattractive habitats like winter road beds that are salted to melt snow and ice. The nest is well-hidden on a horizontal branch of a tree, often a conifer.
Migration by this bird is highly variable, probably related to food supply. Large numbers may move south in some years; hardly any in others. This species is one of a few species that are considered "irruptive winter finches" because of the high variability of their movements based on the success of crops from year to year.
These birds forage in trees, shrubs and weeds. They mainly eat seeds, plant parts and some insects. In winter, they often feed in mixed flocks including American goldfinches and redpolls. Small seeds, especially thistle, red alder, birch, and spruce seeds, make up the majority of the pine siskin's diet. In a part of their esophagus called the crop, the species can store up to 10% of their body weight in seeds overnight, providing extra food on cold days. They will alternately eat the young buds of willows, elms and maples, and the soft stems and leaves of weeds and even young garden vegetables. They'll glean the seeds of grass, dandelions, chickweed, sunflowers and ragweed. Bird feeders often attract pine siskins, where they may eat fragments of heavy-shelled seeds, such as black oil sunflowers, left behind by heavier-billed bird species. In summer, they will eat many insects, especially aphids, as well as a few spiders and grubs, which they then feed to the young as a protein-rich food that contributes to their growth. By the time of winter, even first year siskins predominately eat seeds.
Pine siskins can survive in very cold temperatures. The metabolic rates of this species are typically 40% higher than a "normal" songbird of their size. When temperatures plunge as low as −70 °C (−94 °F), they can accelerate that rate up to five times normal for several hours. They also put on half again as much winter fat as their common redpoll and American goldfinch relatives. They also can protect their young from cold as well. Nests are often heavily insulated with thick plant materials and females may literally never cease incubating their eggs and hatchlings, while being fed by their male mate.
Although considered Washington's most common finch, the pine siskin has suffered a significant annual decline in population since 1966, according to the Breeding Bird Survey. Due to the irruptive nature of this species, populations vary widely from year to year, and trends can be difficult to interpret. Parasitism by brown-headed cowbirds can have a significant impact on pine siskin productivity, and forest fragmentation has increased their contact with cowbirds. Maintaining large tracts of coniferous forest will help keep this bird common.
Taxonomy and evolution
• The Eurasian siskin, S. spinus is the ancestor of pine siskin, Antillean siskin, S. dominicensis, and black-capped siskin, S. atriceps. The sub-species S. pinus perplexus may be closer to S. atriceps; they both thrive in the Guatemalan-Mexican altiplano.
• This siskin seems to belong to the North American Spinus/Carduelis evolutive radiation, whose parental species is the Eurasian siskin. This finch may have displaced from America to the parental species Eurasian siskin.
- BirdLife International (2012). "Carduelis pinus". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
- All About Birds Cornell Lab of Ornithology. Retrieved 29 May 2011.
- Lethaby(1997) - reference relates to whole paragraph
- Arnaiz-Villena A, Ruiz-del-Valle V, Moscoso J, Serrano Vela JI, Zamora J (2007). "mtDNA phylogeography of North American Carduelis pinus group of birds" (PDF). Ardeola 54: 1–14. Retrieved 20 July 2010.
- Arnaiz-Villena, A; Areces C; Rey D; Enríquez-de-Salamanca M; Alonso-Rubio J; Ruiz-del-Valle V (2012). "Three Different North American Siskin/Goldfinch Evolutionary Radia-tions (Genus Carduelis): Pine Siskin Green Morphs and European Siskins in America" (PDF). The Open Ornithology Journal 5: 73–81. doi:10.2174/1874453201205010073.
- Arnaiz-Villena, Antonio; Alvarez-Tejado M.; Ruiz-del-Valle V.; García-de-la-Torre C.; Varela P; Recio M. J.; Ferre S.; Martinez-Laso J. (1998). "Phylogeny and rapid Northern and Southern Hemisphere speciation of goldfinches during the Miocene and Pliocene Epochs" (PDF). Cell.Mol.Life.Sci. 54 (9): 1031–41. doi:10.1007/s000180050230. PMID 9791543.
- Zamora, J; Moscoso J; Ruiz-del-Valle V; Ernesto L; Serrano-Vela JI; Ira-Cachafeiro J; Arnaiz-Villena A (2006). "Conjoint mitochondrial phylogenetic trees for canaries Serinus spp. and goldfinches Carduelis spp. show several specific polytomies" (PDF). Ardeola 53 (1): 1–17.
- Arnaiz-Villena, A; Gómez-Prieto P; Ruiz-de-Valle V (2009). "Phylogeography of finches and sparrows". Nova Science Publishers. ISBN 978-1-60741-844--3.
- Arnaiz-Villena, A.; Guillén, J.; Ruiz-del-Valle, V.; Lowy, E.; Zamora, J.; Varela, P.; Stefani, D.; Allende, L. M. (2001). "Phylogeography of crossbills, bullfinches, grosbeaks, and rosefinches" (PDF). Cellular and Molecular Life Sciences 58 (8): 1159–1166. doi:10.1007/PL00000930. PMID 11529508.
- Zamora, Jorge; Lowy E; Ruiz-del-Valle V; Moscoso J; Serrano-Vela JI; Rivero-de-Aguilar J; Arnaiz-Villena A (2006). "Rhodopechys obsoleta (desert finch): a pale ancestor of greenfinches according to molecular phylogeny" (PDF). J Ornithol 147: 448–56. doi:10.1007/s10336-005-0036-2.
- Arnaiz-Villena, A.; Moscoso, J.; Ruiz-del-Valle, V.; Gonzalez, J.; Reguera, R.; Wink, M.; Serrano-Vela, J. I. (2007). "Bayesian phylogeny of Fringillidae birds: status of the singular African oriole finch Linurgus olivaceus and evolution and heterogeneity of the genus Carpodacus" (PDF). Acta Zoologica Sinica 53 (5): 826–834. Retrieved 14 December 2009.
- Arnaiz-Villena, A; Moscoso J; Ruiz-del-Valle V; González J; Reguera R; Ferri A; Wink M; Serrano-Vale JI (2008). "Mitochondrial DNA Phylogenetic Definition of a Group`of "Arid-Zone" Carduelini Finches" (PDF). The Open Ornithology Journal 1: 1–7. doi:10.2174/1874453200801010001.
- Dawson, W. R. 1997. Pine Siskin (Carduelis pinus). In The Birds of North America, No. 280 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists’ Union, Washington, D.C.
- Lethaby, Nick (1997) Identification of Pine Siskin Birding World 10(10): 383-6 (covers separation from Eurasian siskin C. spinus)
- Astheimer, L; Ramenofsky, M; Wingfield, JC; Buttemer, W (1989). "Corticosterone Feeding Behavior and Food Deprivation in Passerine Birds". American Zoologist 29: 4.
- Astheimer, LB; Buttemer, WA; Wingfield, JC (1992). "Interactions of corticosterone with feeding, activity and metabolism in passerine birds". Ornis Scandinavica 23 (3): 355–365. doi:10.2307/3676661.
- Balph, DF; Balph, MH (1979). "Behavioral Flexibility of Pine Siskins in Mixed Species Foraging Groups". Condor 81 (2): 211–212. doi:10.2307/1367295.
- Benkman, CW; Lindholm, AK (1991). "The Advantages and Evolution of a Morphological Novelty". Nature 349 (6309): 519–520. doi:10.1038/349519a0.
- Bennetts, RE; Hutto, RL (1985). "Attraction of Social Fringillids to Mineral Salts an Experimental Study". Journal of Field Ornithology 56 (2): 187–189.
- Bledsoe, AH (1988). "Nuclear DNA Evolution and Phylogeny of the New World Nine-Primaried Oscines". Auk 105 (3): 504–515.
- Brogden, KA; Packer, RA (1979). "Comparison of Pasteurella-Multocida Serotyping Systems". American Journal of Veterinary Research 40 (9): 1332–1335.
- Brown, WB (1986). "Late Pine Siskins in Ben Hill County Georgia USA". Oriole 51: 2–3.
- Buttemer, WA; Astheimer, LB; Wingfield, JC (1991). "The Effect of Corticosterone on Standard Metabolic Rates of Small Passerine Birds". Journal of Comparative Physiology B Biochemical Systemic & Environmental Physiology 161 (4): 427–432. doi:10.1007/bf00260804.
- Cook, AG (1984). "Birds of the Desert Region of Uintah County Utah USA". Great Basin Naturalist 44 (4): 584–620.
- Dawson, WR; Marsh, RL (1986). "Winter Fattening in the American Goldfinch Carduelis-Tristis and the Possible Role of Temperature in Its Regulation". Physiological Zoology 59 (3): 357–368.
- Dieni, JS; Anderson, SH (1999). "Effects of recent burning on breeding bird community structure in aspen forests". Journal of Field Ornithology 70 (4): 491–503.
- Elder, DH (2001). "Forest tent caterpillars and birds". Ontario Birds 19 (2): 87–88.
- Erickson, WR (2004). "Bird communities of the garry oak habitat in southwestern British Columbia". Canadian Field Naturalist 118 (3): 376–385.
- Farmer, KL; Hill, GE; Roberts, SR (2005). "Susceptibility of wild songbirds to the house finch strain of Mycoplasma gallisepticum". Journal of Wildlife Diseases 41 (2): 317–325. doi:10.7589/0090-3558-41.2.317.
- Hahn TP, Pereyra ME & Sharbaugh SM. (2003). Effects of photoperiod on brain GnRH plasticity and peripheral reproductive physiology in three species of cardueline finches. Society for Neuroscience Abstract Viewer & Itinerary Planner. p. 611.
- Hahn, TP; Pereyra, ME; Sharbaugh, SM; Bentley, GE (2004). "Physiological responses to photoperiod in three cardueline finch species". General & Comparative Endocrinology 137 (1): 99–108. doi:10.1016/j.ygcen.2004.02.014.
- Hahn, TP; Pereyra, ME; Sharbaugh, SM; Morton, ML (2002). "Reproductive responses to long and short days in three high latitude species of cardueline finches". Hormones & Behavior 41: 4.
- Hejl, SJ; Mack, DE; Young, JS; Bednarz, JC; Hutto, RL (2002). "Birds and changing landscape patterns in conifer forests of the north-central Rocky Mountains". Studies in Avian Biology 25: 113–129.
- Herbers, JR; Serrouya, R; Maxcy, KA (2004). "Effects of elevation and forest cover on winter birds in mature forest ecosystems of southern British Columbia". Canadian Journal of Zoology 82 (11): 1720–1730. doi:10.1139/z04-151.
- Hill, GE; McGraw, KI (2004). "Correlated changes in male plumage coloration and female mate choice in cardueline finches". Animal Behaviour 67 (1): 27–35. doi:10.1016/j.anbehav.2003.02.002.
- Hobson, KA; Bayne, E (2000). "Breeding bird communities in boreal forest of western Canada: Consequences of "unmixing" the mixedwoods". Condor 102 (4): 759–769. doi:10.1650/0010-5422(2000)102[0759:bbcibf]2.0.co;2.
- Hobson, KA; Schieck, J (1999). "Changes in bird communities in boreal mixedwood forest: Harvest and wildfire effects over 30 years". Ecological Applications 9 (3): 849–863. doi:10.1890/1051-0761(1999)009[0849:cibcib]2.0.co;2.
- Jennings, DT; Crawford, HS (1983). "Pine Siskin Preys on Egg Masses of the Spruce Budworm Choristoneura-Fumiferana Lepidoptera Tortricidae". Canadian Entomologist 115 (4): 439–440. doi:10.4039/ent115439-4.
- Jim, S; Keith, AH (2000). "Bird communities associated with live residual tree patches within cut blocks and burned habitat in mixedwood boreal forests". Canadian Journal of Forest Research 30 (8): 1281. doi:10.1139/x00-061.
- Kaufman, K (1993). "Notes on goldfinch identification". American Birds 47 (1): 159–162.
- Keller, ME; Anderson, SH (1992). "Avian Use of Habitat Configurations Created by Forest Cutting in Southeastern Wyoming". Condor 94 (1): 55–65. doi:10.2307/1368795.
- Koenig, WD (2001). "Synchrony and periodicity of eruptions by boreal birds". Condor 103 (4): 725–735. doi:10.1650/0010-5422(2001)103[0725:sapoeb]2.0.co;2.
- Koenig, WD; Knops, JMH (2001). "Seed-crop size and eruptions of North American boreal seed-eating birds". Journal of Animal Ecology 70 (4): 609–620. doi:10.1046/j.1365-2656.2001.00516.x.
- Kubisz, MA (1989). "Burdock as a Hazard to Golden-Crowned Kinglets and Other Small Birds". Ontario Birds 7 (3): 112–114.
- Lagory, KE; Lagory, MK; Meyers, DM; Herman, SG (1984). "Niche Relationships in Wintering Mixed Species Flocks in Western Washington USA". Wilson Bulletin 96 (1): 108–116.
- Langelier, LA; Garton, EO (1986). "Management Guidelines for Increasing Populations of Birds That Feed on Western Spruce Budworm". U S Department of Agriculture Handbook 653: 1–19.
- Larson, DL; Bock, CE (1986). "Eruptions of Some North American Boreal Seed-Eating Birds 1901-1980". Ibis 128 (1): 137–140. doi:10.1111/j.1474-919x.1986.tb02101.x.
- Lawler, JJ; O'Connor, RJ; Hunsaker, CT; Jones, KB; Loveland, TR; White, D (2004). "The effects of habitat resolution on models of avian diversity and distributions: a comparison of two land-cover classifications". Landscape Ecology 19 (5): 515–530. doi:10.1023/b:land.0000036151.28327.01.
- MacDougall-Shackleton, SA; Hahn, TP (1999). "Photorefractoriness and the evolution of reproductive flexibility in cardueline finches". American Zoologist 39: 5.
- MacDougall-Shackleton, SA; Katti, M; Hahn, TP (2006). "Tests of absolute photorefractoriness in four species of cardueline finch that differ in reproductive schedule". Journal of Experimental Biology 209 (19): 3786–3794. doi:10.1242/jeb.02447.
- Manuwal, DA; Huff, MH (1987). "Spring and Winter Bird Populations in a Douglas-Fir Forest Sere". Journal of Wildlife Management 51 (3): 586–595. doi:10.2307/3801273.
- McLaren, IA; Morlan, J; Smith, PW; Gosselin, M; Bailey, SE (1989). "Eurasian Siskins in North America Distinguishing Females from Green-Morph Pine Siskins". American Birds 43 (5): 1268–1274.
- Medin, DE (1984). "Breeding Birds of an Ancient Bristlecone Pine Pinus-Longavo Stand in East Central Nevada USA". Great Basin Naturalist 44 (2): 272–276.
- Mills, A (1986). "Correlations among Winter Finch Numbers at Ottawa Canada 1958-1983". Ontario Birds 4 (1): 30–32.
- Moore, T (1990). "Pine siskins remain until June in Fulton County". Oriole 55: 2–3.
- Mundinger, PC (1979). "Call Learning in the Carduelinae Ethological and Systematic Considerations". Systematic Zoology 28 (3): 270–283. doi:10.2307/2412582.
- Nagle, L; Kreutzer, M; Vallet, E (2002). "Adult female canaries respond to male song by calling". Ethology 108 (5): 463–472. doi:10.1046/j.1439-0310.2002.00790.x.
- Oberle, MW; Haney, JC (1997). "Possible breeding range extensions of northern forest birds in northeast Georgia". Oriole 62 (3-4): 35–44.
- Pereyra, ME; MacDougall-Shackleton, SA; Sharbaugh, SM; Morton, ML; Katti, M; Hahn, TP (2001). "Relationships between photorefrac-toriness and reproductive flexibility in cardueline finches". American Zoologist 41: 6.
- Pereyra, ME; Sharbaugh, SM; Hahn, TP (2003). "Interspecific variation in photo-induced hypothalamic GnRH plasticity in cardueline finches". Integrative & Comparative Biology 43: 6.
- Pereyra, ME; Sharbaugh, SM; Hahn, TP (2005). "Interspecific variation in photo-induced GnRH plasticity among nomadic cardueline finches". Brain Behavior & Evolution 66 (1): 35–49. doi:10.1159/000085046.
- Popp, JW (1988). "Scanning Behavior of Finches in Mixed-Species Groups". Condor 90 (2): 510–512. doi:10.2307/1368587.
- Popp, JW (1989). "Use of Agonistic Displays by Purple Finches During Interspecific Encounters". Bird Behavior 8 (1): 48–50. doi:10.3727/015613888791871304.
- Prescott, DRC (1985). "Feeding at Night by Wintering Pine Siskins Carduelis-Pinus". Journal of Field Ornithology 56: 4.
- Rohweder, MR; McKetta, CW; Riggs, RA (2000). "Economic and biological compatibility of timber and wildlife production: an illustrative use of production possibilities frontier". Wildlife Society Bulletin 28 (2): 435–447.
- Roland, J; Hannon, SJ; Smith, MA (1986). "Foraging Pattern of Pine Siskins Carduelis-Pinus and Its Influence on Winter Moth Operophtera-Brumata Survival in an Apple Orchard". Oecologia 69 (1): 47–52. doi:10.1007/bf00399036.
- Scott, VE; Crouch, GL (1987). "Response of Breeding Birds to Commercial Clearcutting of Aspen in Southwestern Colorado USA". U S Forest Service Research Note RM 475: 1–5. doi:10.5962/bhl.title.99219.
- Tallman, DA; Zusi, RL (1984). "A Hybrid Red Crossbill Pine Siskin Loxia-Curvirostra X Carduelis-Pinus and Speculations on the Evolution of Loxia". Auk 101 (1): 155–158.
- Unitt, P; Rodriguez Estrella, R; Castellanos Vera, A (1992). "Ferruginous hawk and pine siskin in the Sierra De La Laguna, Baja California Sur: Subspecies of the pine siskin in Baja California". Western Birds 23 (4): 171–172.
- Wright, DH (1996). "Intermittent birding at Prince Albert, 1982-1985". Blue Jay 54: 3.
- Yunick, RP (1976). "DELAYED MOLT IN PINE SISKIN". Bird-Banding 47 (4): 306–309. doi:10.2307/4512265.
- Zamora, J; Ernesto, L; Ruiz-del-Valle, V; Moscoso, J; Serrano-Vela, JI; Rivero-de-Aguilar, J; Arnaiz-Villena, A (2006). "Rhodopechys obsoleta (desert finch): a pale ancestor of greenfinches (Carduelis spp.) according to molecular phylogeny". Journal of Ornithology 147 (3): 448–456. doi:10.1007/s10336-005-0036-2.
- Zinkl, JG; Henny, CJ; Lenhart, DJ; Roberts, RB (1980). "Inhibition of Brain Cholin Esterase Activity in Forest Birds and Squirrels Exposed to Aerially Applied Acephate". Bulletin of Environmental Contamination & Toxicology 24 (5): 676–683. doi:10.1007/bf01608173.
|Wikimedia Commons has media related to pine siskin.|
|Wikispecies has information related to: Carduelis pinus|