Ochotona princeps (Richardson, 1828)

Don E. Wilson, Thomas E. Lacher, Jr & Russell A. Mittermeier, 2016, Ochotonidae, Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I, Barcelona: Lynx Edicions, pp. 28-43 : 38-39

17.

American Pika

Ochotona princeps

French: Pika dAmérique / German: Amerikanischer Pfeifhase / Spanish: Pica americana

Other common names: Cony, Rock Rabbit, Whistling Hare

Taxonomy. Lepus (Lagomys) princeps Richardson, 1828 ,

“Rocky Mountains.” Restricted by E. A. Preble in 1908 to “near the sources of Elk (Athabasca) River.”

According to mtDNA and nDNA, O. princeps belongs to subgenus Pika. This species previously included O. collaris , but this sister species was found to be separate based on morphology, chromosomes, and,later, genetic markers. Number of subspecies decreased from 36 to five; subspecies were designated on based on pelage color, body size, bioacoustic features, and allozyme variation. Recent subspecific taxonomy is based on mtDNA and nDNA markers and partly correlates with morphology and bioacoustics. According to morphological study, O. princeps includes albata, barnesi, brooksi, brunnescens, cinnamomea, clamosa, cuppes, fenisex, figginsi, fumosa, fuscipes, goldmani, howelli, incana, jewetti, lasalensis, lemha, levis, littoralis, lutescens, minimus, moore, muiri, nevadensis, nigrescens, obscura, saturata, saxatilis, schisticeps, septentrionalis, shelton, taylori, tutelata, winta, utahensis, ventorum, and wasatchensis. Five subspecies recognized.

Subspecies and Distribution.

O.p.princepsRichardson,1828—NRockyMts,SWCanada(SEBritishColumbia,SWAlberta)andNWUSA(MontanaandIdahotoNENevadaandNColorado).

O.p.fenisexOsgood,1913—CoastandCascaderanges,SWCanada(SBritishColumbia)andNWUSA(Washington,WOregon).

O.p.saxatilisBangs,1899—SRockyMts,USA(Colorado,NNewMexico).

O.p.schisticepsMerriam,1889—SierraNevadaandGreatBasin,SWUSA(EOregon,ECalifornia,Nevada,SWUtah).

O. p. winta Hollister, 1912 — Uinta Mts and Wasatch Range of C Utah, W USA.

Descriptive notes. Head-body 160-200 mm, ear 23-26 mm, hindfoot 27-34 mm; weight 121-176 g. The American Pika is medium-sized. Dorsal fur is grayish to cinnamon brown. Ventral fur is whitish, with a shade of buffy; neck is more yellow. Winter fur is longer, softer and grayer than during other seasons. Hairs above neck gland are rusty brown. Ears are rounded, with white margins. Skull is medium-sized and stout, with incisive and palatal foramens separated. Auditory bullae are medium-sized. Condylobasal lengths are 38—44 mm, skull widths are 20-23 mm, and skull heights are 14-16 mm. The American Pika differs from the Collared Pika ( O. collaris ) by presence of buffy tint on belly and absence of light gray collar.

Habitat. Talus or piles of broken rocks, edged with some vegetation, at elevations of ¢.1200-3500 m, with lower elevational limits increasing southward in its distribution. The American Pika is a typical rock dweller.

Food and Feeding. American Pikas feed on green plants and store hay in hay piles. Hoarding of hay starts in July, depending on weather. Dimensions of hay piles reach 0-6 by 0-8 m and bigger. As in most rock-dwelling pikas, hay piles reflect composition of local vegetation; however, some plant species are avoided, while some are preferred. Hay piles are usually situated under large stones or openly on talus. During cold periods, American Pikas eat hay, but experimental removal of hay piles in autumn did not influenced winter survival. Lichens and cushion plants play important role in winter diets.

Breeding. Breeding of the American Pika starts in February-March, but dates depend on snowmelt. Most commonly, parturition occurs in May and peaks in June. Adult females can breed 1-2 times/year, but the second breeding is usually least successful. Young-of-the-year do not breed. Each female usually has 2-4 embryos. Gestation is ¢.30 days, and neonates are covered with sparse fur and born with closed eyes that open at 9 days of age. Lactation lasts 3-4 weeks. Young becomesrelatively independent at 4 weeks old. American Pikas avoid breeding with first-order relatives.

Activity patterns. The American Pika is diurnal, and it is active aboveground c.30% of daylight hours in summer. Surface activity decreases in winter and reaches a minimum in February—-April.

Movements, Home range and Social organization. The American Pika moves aboveground by running and leaping openly. Home ranges are ¢.1000-2200 m?, depending on location and method of analysis. Defended core areas are 410-709 m?. Males and females have overlapping home ranges of similar sizes. Although American Pikas form spatial pairs, mating often occurs between non-neighboring pikas. Densities are 220-990 ind/km?. Areas occupied are marked with old hay piles, latrines, and white urine markings. Two distinct vocalizations of the American Pika serve to alarm and function in social interactions.

Status and Conservation. Classified as Least Concern on The IUCN Red List.

Bibliography. Broadbooks (1965), Conner (1983), Galbreath et al. (2010), Hafner & Smith (2010), Lanier & Olson (2009), Melo-Ferreira et al. (2015), Millar & Zwickel (1972), Peacock & Smith (1997), Preble (1908), Smith & Weston (1990).

Figures

15. Kazakh Pika (Ochotona opaca), 16. Silver Pika (Ochotona argentata), 17. American Pika (Ochotona princeps), 18. Collared Pika (Ochotona collaris), 19. Steppe Pika (Ochotona pusilla), 20. Large-eared Pika (Ochotona macrotis), 21. Royle’s Pika (Ochotona roylu), 22. Afghan Pika (Ochotona rufescens), 23. Forrest's Pika (Ochotona forrest), 24. Ladak Pika (Ochotona ladacensis), 25. Turkestan Red Pika (Ochotona rutila), 26. Kozlov’s Pika (Ochotona koslowi), 27. Chinese Red Pika (Ochotona erythrotis), 28. Glover’s Pika (Ochotona gloveri), 29. Ili Pika (Ochotona iliensis)

Subspecies and Distribution. O.p.princepsRichardson,1828—NRockyMts,SWCanada(SEBritishColumbia,SWAlberta)andNWUSA(MontanaandIdahotoNENevadaandNColorado). O.p.fenisexOsgood,1913—CoastandCascaderanges,SWCanada(SBritishColumbia)andNWUSA(Washington,WOregon). O.p.saxatilisBangs,1899—SRockyMts,USA(Colorado,NNewMexico). O.p.schisticepsMerriam,1889—SierraNevadaandGreatBasin,SWUSA(EOregon,ECalifornia,Nevada,SWUtah). O. p. winta Hollister, 1912 — Uinta Mts and Wasatch Range of C Utah, W USA.