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Tule elk
Tule elk bull at San Luis National Wildlife Refuge
Tule elk cow at Tomales Point, Point Reyes National Seashore
Vulnerable
Vulnerable  (NatureServe)[1]
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Cervidae
Genus: Cervus
Species:
C. canadensis
Subspecies:
C. c. nannodes
Trinomial name
Cervus canadensis nannodes
(Merriam, 1905)
Synonyms
  • Cervus elaphus nannodes
  • Cervus nannodes

The tule elk (Cervus canadensis nannodes) is a subspecies of elk found only in California, ranging from the grasslands and marshlands of the Central Valley to the grassy hills on the coast. When the Europeans first arrived, an estimated 500,000 tule elk roamed these regions, but by 1870 they were thought to be extirpated. In 1874–1875 a single breeding pair was discovered in the tule marshes of Buena Vista Lake in the southern San Joaquin Valley. Conservation measures were taken to protect the species in the 1970s.

They are considered the smallest subspecies of wapiti, which is reflected in the alternative name "dwarf wapiti" and their scientific name, which means "dwarf". However, some individuals have grown to the size of Roosevelt elk, the largest wapiti subspecies. Herds typically included around hundreds of individuals, though several herds may have included thousands of wapiti.

Initially, tule wapiti extended southwards to Orange County and may have roamed extreme western Nevada. When Spanish arrived, tule wapiti populations fell as a result of competition with livestock, habitat loss, and overhunting. Tule wapiti were believed to have gone extinct by 1873, the year when wapiti hunting was banned. Once they were rediscovered, efforts by ranchers in the 20th century aided in the tule wapiti's survival.

Taxonomy

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The tule wapiti was identified by Clinton Hart Merriam as a distinct species Cervus nannodes in 1905 from a 2-year old bull from Buttonwillow, California. Merriam placed the tule wapiti in a separate species, commenting on its paler fur, smaller size, and shorter legs compared to other wapiti. He reported some affinity between the tule wapiti and the Rocky Mountain wapiti based on a comparison of skulls.[2]

A taxonomic revision by British naturalist Richard Lydekker placed the tule wapiti and other wapiti in the species Cervus canadensis. He classified wapiti from the White Mountains and Mogollon Mountains as extinct populations of tule wapiti, though modern taxonomists classify these populations as a subspecies named Merriam's wapiti.[3][4] Many naturalists classified the wapiti as various subspecies of red deer, following Johann Erxleben's initial description.[5] Mitochondrial DNA studies conducted in 2004 strongly indicated wapiti are a separate species from red deer.[6]

Genetic studies based on mitochondrial and nuclear DNA confirm that tule wapiti, Roosevelt wapiti and Rocky Mountain wapiti should be considered distinct subspecies.[7][8] A 2007 nuclear DNA microsatellite study found single alleles at many loci, with a maximum of five alleles at one locus, indicating that there has either been a mutation at this locus subsequent to the single breeding pair reported by Henry Miller and nineteenth century game warden A. C. Tibbet, or there were three surviving tule wapiti at the 1800s genetic bottleneck.[8] Another microsatellite study in 2016 found no more than four alleles at any locus, consistent with tule wapiti having been reduced to a single breeding pair.[9] The subspecific epithet nannodes means "dwarf", in reference to the tule wapiti's small size.[10] The subspecies name derives from the tule (/ˈtuːliː/), a species of sedge native to freshwater marshes where a few remaining animals were discovered.

Description

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A tule wapiti bull at Point Reyes National Seashore in 2018

Considered the smallest of the wapiti subspecies in North America, the tule wapiti were the dominant large ungulate in California prior to the arrival of the Spanish. The average weight of adult males is 450 to 550 lb (200 to 250 kg) and females have an average of 375 to 425 lb (170 to 193 kg). Although tule wapiti have been reported as half the size of the Roosevelt wapiti (C. c. roosevelti), and sometimes referred to as the dwarf wapiti, this moniker may be misleading as the smaller size of some tule wapiti may reflect poor nutrition of wapiti subsisting on marginal habitat such as the Owens River watershed. California Department of Fish and Wildlife records show recent tule wapiti bulls on Grizzly Island in Suisun Bay weigh up to 900 pounds (410 kg).[11] This is a similar size to Roosevelt wapiti bulls which weigh between 700 pounds (320 kg) and 1,100 pounds (500 kg).[12] Wildlife biologist Dale McCullough described a wapiti transplanted from Buttonwillow in the San Joaquin Valley to a golf course in Monterey that grew to the size of a Rocky Mountain wapiti.[13] Also hunter H. C. Banta described the tule wapiti in the 1850s as "I found no difference in size between these wapiti and the Oregon, Washington, Wyoming and Colorado elk, and felt sure that the bulls would weight 700 to 800 pounds".[11]

The calves are similar to deer fawns, with brown coats and white spots. Tule wapiti herd size likely numbered in the several hundreds historically. Joseph Warren Revere, the grandson of Revolutionary War patriot Paul Revere, wrote in his book Naval Duty in California that he counted 400 wapiti in a single herd on Pt. Reyes in the 1840s.[14] Stephen J. Richardson, son of Marin County pioneer Captain William A. Richardson, wrote "I think the largest herd in the world roamed over the deep grasslands of Point Reyes...I fully believe there were a thousand elk in one herd."[15] General John Bidwell of the 1841 Bartleson–Bidwell Party wrote: "In some of the fertile valleys, such as Napa and Santa Clara, there were elk literally by the thousand".[16]

Biology

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Making rutting call or "bugle"

Diet

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Two male and eight female wapiti were translocated from Merced County, California to Tomales Point on Point Reyes National Seashore in March 1978. The wapiti showed signs of nutritional stress including copper deficiency and antler anomalies by summer 1979 and two wapiti died. One explanation was molybdenum which expresses as copper deficiency. A former molybdenum mine existed in that area of the Point Reyes National Seashore. Other possible explanations include failure to remove cattle until 1979 and the fact that 1977 and 1978 were drought years. Birth rates remained negligible until 1981, when they began reproducing at predicted maximum rates. Studies of fecal material documented that the tule wapiti preferred grasses and forbs with little use of shrubs such as willow.[17] These results are consistent with findings on the Diablo Range, Santa Clara County wapiti herd where more than 50% of the tule wapiti diet were grasses.[18]

A 2007 study at the Tomales Point Elk Reserve showed that tule wapiti appear to play a critical role in preventing succession of open grasslands to less diverse, shrub-dominated ecosystems. Wapiti grazing had a positive impact on native grassland species abundance and diversity, and seemed to increase the richness and abundance of some exotic taxa while reducing Holcus lanatus—a highly invasive exotic grass which is a major problem in mesic perennial grasslands.[19]

Pathology

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Small numbers of tule wapiti in Point Reyes have tested positive for Mycobacterium avium subspecies paratuberculosis or "MAP", a wasting disease known as Johne's Disease. The bacteria was apparently transmitted by dairy cattle or spraying of cattle manure on pasturelands. In 2016 more tule wapiti tested positive after being euthanized so that their gut tissue could be analyzed. Cattle transmitted the disease to the Tomales Point wapiti herd shortly after they were first established there in 1978.[20]

Distribution and habitat

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Distribution of the tule wapiti in 1994

Tule wapiti are found exclusively in California and are spotted in Carrizo Plain National Monument, Point Reyes National Seashore, portions of the Owens Valley from Lone Pine to Bishop, Coyote Ridge in Santa Clara Valley, San Jose, California and in Pacheco State Park and areas surrounding San Luis Reservoir near Los Banos, California.

Historically, they ranged from Orange County to the Sierra Nevada and possibly extreme western Nevada.[21][22] McCullough identified nineteenth century tule wapiti antler specimens collected in three separate locations north of the San Francisco Bay: Sonoma in Sonoma County, as well as San Geronimo and Tomales both in Marin County.[23]

Conservation status

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Before European colonization, the overall tule wapiti population composed of more than 500,000 individuals.[24] After the Spanish arrived, grazing livestock such as cattle and horses were introduced and competed with the native wapiti for food.[25] Other factors to wapiti decline included habitat loss and overhunting. By 1873, when wapiti hunting was banned, tule wapiti were believed to had gone extinct.[26] In 1874, German American rancher Henry Miller discovered a population consisting of 2–10 wapiti on his ranch in Bakersfield, and through his efforts, the Tule wapiti population rose to 28 in 1895.[27]

Miller's herd was transplanted 21 times, with each attempt failing to establish free-ranging herds.[24] Walter Dow transferred 27 head from Yosemite National Park and 28 from Tupman to Owens Valley. This herd thrived in the new habitat and comprised 200 head by 1943.[28] In 1960, the state of California held a hearing to determine how many wapiti should live in the Owens Valley, and decided they wapiti should be hunted to limit their numbers to under 500 animals.[23][29]

A private citizen from Los Angeles, Beula Edmiston, formed a group to attempt a preservation program for the Tule wapiti. After more than 10 years of lobbying both on the federal and state levels, in 1971, California passed legislation (the Behr bill) requiring the wapiti may not be hunted until their numbers surpass 2,000 head statewide or until it could be determined that suitable wapiti habitat no longer existed in the state, and mandated the California Department of Resources to reintroduce the wapiti into former habitats wherever possible.[24]

By 1986 numbers had increased to over 2,000 individuals distributed among 22 populations throughout California, largely due to successful reintroduction programs.[30] By 1998, California's tule wapiti population exceeded 3,200.[31][32] In 2007, the statewide population was estimated at 3,800.[33] A 2014 report placed the statewide population at 4,200 in 22 herds.[34] As of 2019, the total Californian population was estimated to be 5,700.[35]

References

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  1. ^ NatureServe. 1988. Cervus elaphus nannodes, Tule Elk. NatureServe, Arlington, Virginia. Available https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.103199/Cervus_elaphus_nannodes. Accessed 9 December 2021.
  2. ^ Merriam, Clinton Hart (February 2, 1905). "A new elk from California, Cervus nannodes". Proceedings of the Biological Society of Washington. 18 (1). Washington D.C.: Biological Society of Washington.
  3. ^ Lydekker, Richard (1915). Catalogue of the Ungulate Mammals in the British Museum (Natural History). order of the Trustees.
  4. ^ Fairweather, Mary Lou; Giles, Brian; Manthei, Mike (January 1, 2008). "Aspen Decline on the Coconino National Forest". Proceedings of the 55th Annual Western International Forest Disease Work Conference. Salem, Oregon: Oregon Department of Forestry: 53–62.
  5. ^ Erxleben, J.C.P. (1777). Anfangsgründe der Naturlehre and Systema regni animalis. Göttingen.
  6. ^ Ludt, Christian J.; Schroeder, Wolf; Rottmann, Oswald; Kuehn, Ralph (2004). "Mitochondrial DNA phylogeography of red deer (Cervus elaphus)". Molecular Phylogenetics and Evolution. 31 (3): 1064–1083. Bibcode:2004MolPE..31.1064L. doi:10.1016/j.ympev.2003.10.003. PMID 15120401.
  7. ^ R.O. Polziehn; J. Hamr; F.F. Mallory; C. Strobeck (1998). "Phylogenetic status of North American wapiti (Cervus elaphus) subspecies". Canadian Journal of Zoology. 76 (6): 998–1010. Bibcode:1998CaJZ...76..998P. doi:10.1139/z98-026.
  8. ^ a b E. P. Meredith; J. A. Rodzen; J. D. Banks; R. Schaefer; H. B. Ernest; T. R. Famula; B. P. May (2007). "Microsatellite Analysis of Three Subspecies of Elk (Cervus elaphus) in California" (PDF). Journal of Mammalogy. 88 (3): 801–808. Bibcode:2007JMamm..88..801M. doi:10.1644/06-mamm-a-014r.1. Retrieved January 20, 2013.
  9. ^ Benjamin N. Sacks; Zachary T. Lounsberry; Tatyana Kalani; Erin P. Meredith; Cristen Langner (2016). "Development and Characterization of 15 Polymorphic Dinucleotide Microsatellite Markers for Tule Elk Using HiSeq3000". Journal of Heredity. 107 (7): 666–669. doi:10.1093/jhered/esw069. PMID 27638816.
  10. ^ Prance, Ghillean T. (1995). "Atuna nannodes (Kosterm.) Kosterm.". In Soepadmo, E.; Wong, K. M. (eds.). Tree Flora of Sabah and Sarawak. (free online from the publisher, lesser resolution scan PDF versions). Vol. 1. Forest Research Institute Malaysia. pp. 158, 160. ISBN 983-9592-34-3. Archived from the original (PDF) on September 27, 2013. Retrieved June 1, 2014.
  11. ^ a b Laura Cunningham (2010). A State of Change: Forgotten Landscapes of California. Heyday. p. 350. ISBN 978-1-59714-136-9.
  12. ^ Robb, Bob (January 2001). The Ultimate Guide to Elk Hunting. The Lyons Press. ISBN 978-1-58574-180-9.
  13. ^ Dale R. McCullough (1969). The Tule Elk, Its History, Behavior, and Ecology, University of California Publications in Zoology. Vol. 88. University of California Press. p. 209. ISBN 978-0-520-01921-8.
  14. ^ Joseph Warren Revere (1947). Naval Duty in California. Oakland, California: Biobooks. p. 245.
  15. ^ Stephen J. Richardson (1918). James Hepburn Wilkins (ed.). Days of the Dons: Reminiscences of California's Oldest Native Son. San Francisco Bulletin.
  16. ^ Rockwell D. Hunt (1942). John Bidwell, Prince of California Pioneers. Caldwell, Idaho: The Caxton Printers, LTD. p. 463.
  17. ^ Peter J. P. Gogan; Reginald H. Barrett (July 1995). "Elk and Deer Diets in a Coastal Prairie-Scrub Mosaic, California". Journal of Range Management. 48 (4): 327–335. Bibcode:1995JRMan..48..327G. doi:10.2307/4002485. hdl:10150/644391. JSTOR 4002485.
  18. ^ Julie A. Phillips (1985). Acclimation of reintroduced tule elk in the Diablo Range, California (M.S. Thesis). San Jose, California: San Jose State University. p. 106. OCLC 12983030.
  19. ^ Brent E. Johnson; J. Hall Cushman (2007). "Influence of a Large Herbivore Reintroduction on Plant Invasions and Community Composition in a California Grassland". Conservation Biology. 21 (2): 515–526. Bibcode:2007ConBi..21..515J. doi:10.1111/j.1523-1739.2006.00610.x. PMID 17391201. S2CID 29377115.
  20. ^ Alison Hawkes (February 28, 2016). "Point Reyes Elk Test Positive for Disease. Are Cattle to Blame?". Bay Nature. Retrieved December 3, 2017.
  21. ^ "South Orange County", A People's Guide to Orange County, University of California Press, pp. 135–159, January 25, 2022, doi:10.2307/j.ctv2j6xf5f.10
  22. ^ Lanman, Richard B.; Batter, Thomas J.; Mckee, Cody J. (September 18, 2024). "Novel evidence that elk were historically native to the Sierra Nevada, and recent range expansions into the region". PLOS ONE. 19 (9) e0301665. doi:10.1371/journal.pone.0301665. ISSN 1932-6203. PMC 11410259. PMID 39292686.
  23. ^ a b Dale R. McCullough (1969). The Tule Elk, Its History, Behavior, and Ecology, University of California Publications in Zoology. Vol. 88. University of California Press. p. 209. ISBN 978-0-520-01921-8.
  24. ^ a b c Laura A. Watt (2015). "The Continuously Managed Wild: Tule Elk at Point Reyes National Seashore". Journal of International Wildlife Law & Policy. 18 (4): 289–308. doi:10.1080/13880292.2015.1096159. S2CID 86127098.
  25. ^ Buechner, Helmut K. (1970). McCullough, D. R. (ed.). "The Tule Elk". BioScience. 20 (15): 890–890. doi:10.2307/1295512. ISSN 0006-3568.
  26. ^ Meredith, E. P.; Rodzen, J. A.; Banks, J. D.; Schaefer, R.; Ernest, H. B.; Famula, T. R.; May, B. P. (2007). "Microsatellite Analysis of Three Subspecies of Elk (Cervus elaphus) in California". Journal of Mammalogy. 88 (3): 801–808. ISSN 0022-2372.
  27. ^ Williams, Christen Lenney; Lundrigan, Barbara; Rhodes Jr., Olin E. (2004). "Microsatellite Dna Variation in Tule Elk". The Journal of Wildlife Management. 68 (1): 109–119. doi:10.2193/0022-541X(2004)068[0109:MDVITE]2.0.CO;2. ISSN 1937-2817.
  28. ^ Young, John V. (April 18, 1968). "California's Giant Effort to Save the Dwarf Elk". The New York Times. p. 25.
  29. ^ Mayer, Steven (February 5, 2019). "Wildlife officials use helicopters to capture 19 tule elk in west Kern for relocation project". The Bakersfield Californian. Retrieved April 10, 2021.
  30. ^ D.R. McCullough; J. K. Fischer; J. D. Ballou (1996). D.R. McCullough (ed.). From bottleneck to metapopulation: recovery of the tule elk in California, in Metapopulations and wildlife conservation. Covelo, California: Island Press. pp. 375–403. ISBN 978-1-55963-458-8.
  31. ^ Linse, Kim (1998). Tule Elk: The Return of A Species (PDF) (Report). National Park Service. Archived (PDF) from the original on October 17, 2013.
  32. ^ Livezey KB. 1993. Tule elk relocated to Brushy Mountain, Mendocino County, California. California Fish and Game 79:131–132.
  33. ^ Julie Phillips; Ryan Phillips; Neela Srinivasan; Deborah Aso; Wendy Lao & Pat Cornely (2012). Safe Passage for the Coyote Valley – A Wildlife Linkage for the Highway 101 Corridor (PDF) (Report). De Anza College. Archived from the original (PDF) on September 27, 2013. Retrieved January 27, 2013.
  34. ^ Elizabeth Devitt (May 7, 2014). "Tule Elk Relocated as Numbers Rebound". Bay Nature. Retrieved February 27, 2016.
  35. ^ "Tule Elk". wildlife.ca.gov. Retrieved November 22, 2020.

Further reading

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  • Changes in Interactions Among Tule Elk Bulls Cervus elaphus nannodes. Joseph Muriuki Wahome, Thesis, University of California, Berkeley, 1995. 330 pages
  • The Return of the Tule Elk-Verna R. Johnston-Pacific Discovery, Vol. 31, Number 1, pages 14–25, Jan–Feb, 1978 California Academy of Sciences, San Francisco
  • The Tule Elk Preservation Act of 1976-Public Law 94-389
  • Tule Elk Management Plan and Environmental Assessment, Oct. 1997
  • History of the California Tule Elk, Gerhard Bakker, Los Angeles City College, 1961
  • Tule Elk in California, History, Current Status, and Management Recommendations, Gene Scott Fowler, UC Berkeley, July 1985
  • Acclimation of Reintroduced Tule Elk in the Diablo Range, California, Julie A.Phillips, Thesis, San Jose State University, May 1985
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