View source for Biology:Pygmy rabbit

{{Short description|Species of mammal}}
{{Speciesbox
| name = Pygmy rabbit<ref name="MSW3">{{MSW3 Lagomorpha|id = 13500094|page = 194}}</ref>
| image = BRACHYLAGUS IDAHOENSIS.jpg
| status = LC 
| status_system = IUCN3.1
| status_ref = <ref name="iucn status 19 November 2021">{{cite iucn |author=Rachlow, J. |author2=Becker, P.A. |author3=Shipley, L. |date=2016 |title=''Brachylagus idahoensis'' |volume=2016 |page=e.T2963A45176206 |doi=10.2305/IUCN.UK.2016-3.RLTS.T2963A45176206.en |access-date=19 November 2021}}</ref>
| genus = Brachylagus
| species = idahoensis
| authority = (Merriam, 1891)
| range_map = Pygmy Rabbit area.png
| range_map_caption = pygmy rabbit range<br/>(blue – native, pink – reintroduced)
| synonyms = ''Lepus idahoensis'' Merriam, 1891<ref name="Merriam">{{cite journal |title=Results of a Biological Reconnoissance of south-central Idaho |author=Merriam, C. Hart |journal=North American Fauna |volume=5 |year=1891 |pages=76–78 |url=https://www.biodiversitylibrary.org/page/45655086}}</ref> ''Lepus (Brachylagus) idahoensis''<ref name="Miller">{{cite journal |title=General Notes: A new subgenus for Lepus idahoensis |author=Miller, Gerrit S., Jr. |journal=Proceedings of the Biological Society of Washington |volume=13 |year=1900 |pages=157 |url=https://www.biodiversitylibrary.org/page/2308273}}</ref> ''Microlagus idahoensis''<ref name="MSW3"/><br>''Sylvilagus idahoensis''<ref name="MSW3"/>
}}

The '''pygmy rabbit''' ('''''Brachylagus idahoensis''''') is a [[Biology:Rabbit|rabbit]] species native to the {{wipe|United States}}. It is also the only native [[Biology:Rabbit|rabbit]] species in [[Earth:North America|North America]] to dig its own burrow.<ref name=":0">{{Cite web|last=Silberstein|first=Maya|title=Leporidae (hares and rabbits)|url=https://animaldiversity.org/accounts/Leporidae/|access-date=2020-08-21|website=Animal Diversity Web|language=en}}</ref><ref name=":1">{{Cite web|title=Pygmy rabbit|url=https://www.fws.gov/nevada/nv_species/pygmy_rabbit.html|access-date=2020-08-21|website=www.fws.gov}}</ref> The pygmy rabbit differs significantly from species within either the ''[[Biology:Hare|Lepus]]'' (hare) or ''[[Biology:Cottontail rabbit|Sylvilagus]]'' (cottontail) [[Biology:Genus|genera]] and is generally considered to be within the [[Biology:Monotypic taxon|monotypic genus]] '''''Brachylagus'''''.  One isolated population, the [[Biology:Columbia Basin pygmy rabbit|Columbia Basin pygmy rabbit]],  is listed as an [[Biology:Endangered species|endangered species]] by the U.S. Federal government, though the [[Organization:International Union for Conservation of Nature|International Union for Conservation of Nature]] lists the species as lower risk.

==Taxonomy==
The pygmy rabbit was first [[Biology:Species description|described]] by Clinton Hart Merriam in 1891, as ''Lepus idahoensis''; the [[Biology:Type|type specimen]], in winter pelage, had been collected in the Pahsimeroi Valley the previous autumn.<ref name="Merriam"/> In 1900, Gerrit S. Miller, Jr. erected the new [[Biology:Subgenus|subgenus]] ''[[Biology:Brachylagus|Brachylagus]]'' for the pygmy rabbit;<ref name="Miller"/> ''Brachylagus'' has since been elevated to the rank of genus.<ref name="MSW3"/> Historically, the pygmy rabbit has also been placed in the genera ''Microlagus'' and ''[[Biology:Sylvilagus|Sylvilagus]]''.<ref name="MSW3"/>

==Description==
The pygmy rabbit is the world's smallest leporid,<ref>{{cite book|page=246|title=The Animal kingdom: the strange and wonderful ways of mammals, birds, reptiles, fishes, and insects; a new and authentic natural history of the wildlife of the world|volume=1|author1=Goodwin, George Gilbert|author2=Drimmer, Frederick|publisher=Cornell University|year=1954|asin=B09SHGMG2M}}</ref><ref>{{cite book|title=Small mammals|author=Goodwin, George C.|publisher=Cornell University|year=1962}}</ref><ref>{{cite book|url=https://archive.org/details/rabbits00shar/page/12|page=[https://archive.org/details/rabbits00shar/page/12 12]|title=Rabbits|author=Sharth, Sharon|year=1999|publisher=Child's World |isbn=156766587X|url-access=registration}}</ref><ref>[http://www.zooborns.com/zooborns/2009/10/columbia-basin-pygmy-rabbits-oregon-zoo-breeding-baby-bunnies.html Meet the World's Smallest Rabbit], October 14, 2009</ref> with adults weighing between {{convert|375|and|500|g|lb|sp=us}}, and having a body length between {{convert|23.5|and|29.5|cm|in|sp=us}}; females are slightly larger than males. The pygmy rabbit is distinguishable from other leporids by its small size, short ears, gray color, small hind legs, and lack of white fuzzy fur.

==Distribution==
The range of the pygmy rabbit includes most of the Great Basin and some of the adjacent intermountain areas of western North America.<ref name=r8/> Pygmy rabbits are found in southwestern Montana from the extreme southwest corner near the Idaho border north to Dillon and Bannack in Beaverhead County.<ref name=r4/> Distribution continues west to southern Idaho and southern Oregon, and south to northern Utah, northern Nevada, and north-eastern California. An isolated population occurs in east-central Washington,<ref name=r2/> and another in Wyoming.<ref name=r21>{{cite journal |author1=Campbell, Thomas M. |author2=Clark, Tim W. |author3=Groves, Craig R. |year=1982 |title=First record of pygmy rabbits (''Brachylagus idahoensis'') in Wyoming |journal=Great Basin Naturalist |volume=42 |issue=1 |pages=100}}</ref>

The elevational range of pygmy rabbits in Nevada extends from {{convert|1370|–|2135|m|ft|sp=us}} and in California from {{convert|1520|–|1615|m|ft|sp=us}}.<ref name=r8/>

The last male purebred [[Biology:Columbia Basin pygmy rabbit|Columbia Basin pygmy rabbit]], found only in the Columbia Basin of {{wipe|Washington (state)}}, died 30&nbsp;March 2006, at the Oregon Zoo in {{wipe|Portland, Oregon}}. The last purebred female died in 2008.<ref>{{cite news |title=Editor's Note |date=January 2009 |magazine=National Geographic Magazine |via=ngm.typepad.com |url=http://ngm.typepad.com/editors_note/2008/12/january-2009.html |url-status=dead <!-- presumed --> |archive-url=https://web.archive.org/web/20090201232931/http://ngm.typepad.com/editors_note/2008/12/january-2009.html |archive-date=2009-02-01}}</ref> A crossbreeding program conducted by the Oregon Zoo, [[Organization:Washington State University|Washington State University]], and Northwest Trek is attempting to preserve the genetic line by breeding surviving females with the Idaho pygmy rabbit.<ref>{{cite news |author=Wiley, John K. |date=13 May 2007 |title=Captive breeding offers hope for near-extinct pygmy rabbits |agency=Associated Press |newspaper=The Seattle Times |url=https://www.seattletimes.com/seattle-news/captive-breeding-offers-hope-for-near-extinct-pygmy-rabbits/ |access-date=1 July 2022}}</ref>

==Lifecycle==
Pygmy rabbits are capable of breeding when they are about 1&nbsp;year old.<ref name=r8/><ref name=r20>{{cite report |author1=Wilde, Douglas B. |author2=Keller, Barry L. |year=1978 |section=An analysis of pygmy rabbit populations on the Idaho National Engineering Laboratory site |editor=Markham, O.D. |title=Ecological studies on the Idaho National Engineering Laboratory site 1978 Progress Report |id=IDO-12087 |place=Idaho Falls, ID |publisher=U.S. Department of Energy / Idaho National Engineering Laboratory |series=Environmental Sciences Branch / [[Organization:Radiological and Environmental Sciences Laboratory|Radiological and Environmental Sciences Laboratory]] |pages=305–316 |osti=6139364}}</ref>

The breeding season of pygmy rabbits is very short. In Idaho it lasts from March through May; in Utah, from February through March.<ref name=r22>{{cite book |editor1=Chapman, Joseph A. |editor2=Feldhamer, George A. |year=1982 |title=Wild mammals of North America |place=Baltimore, MD |publisher=The Johns Hopkins University Press}}</ref> The gestation period of pygmy rabbits is unknown. It is between 27 and 30&nbsp;days in various species of cottontails (''[[Biology:Sylvilagus|Sylvilagus]]'' spp.). An average of six young are born per litter and a maximum of three litters are produced per year.<ref name=r8/> In Idaho the third litter is generally produced in June.<ref name=r20/> It is unlikely that litters are produced in the fall.<ref name=r8/>

The growth rates of juveniles are dependent on the date of birth. Young from early litters grow larger due to a longer developmental period prior to their first winter.<ref name=r8/>

The mortality of adults is highest in late winter and early spring. Green & Flinders (1980)<ref name=r8/> reported a maximum estimated annual adult mortality of 88% in Idaho. Juvenile mortality was highest from birth to 5&nbsp;weeks of age.<ref name=r8/>

Pygmy rabbits may be active at any time of day; however, they are generally most active at dusk and dawn. They usually rest near or inside their burrows during midday.<ref name=r8/>

==Habitat==
Pygmy rabbits are normally found in areas on deep soils with tall, dense [[Biology:Sagebrush|sagebrush]] which they use for shelter and food.<ref name=r8/><ref name=r4>Flath, Dennis. 1994. Bunnies by the bunch. Montana Outdoors. 25(3): 8–13.</ref> Individual sagebrush plants in areas inhabited by pygmy rabbits are often 6 feet (1.8 m) or more in height.<ref name=r4/> Extensive, well-used runways interlace the sage thickets and provide travel and escape routes.<ref name=r8/> Dense
stands of big sagebrush along streams, roads, and fencerows provide dispersal corridors for pygmy rabbits.<ref name=r17>{{cite journal|author1=Weiss, Nondor T.|author2=Verts, B. J.|year=1984|title=Habitat and distribution of pygmy rabbits (''Sylvilagus idahoensis'') in Oregon|journal=Great Basin Naturalist|volume=44|issue=4|pages=563–571|jstor=41712112}}</ref>

The pygmy rabbit is the only leporid native to North America that digs burrows.<ref name=":0"/><ref name=":1"/> Juveniles use burrows more than other age groups. Early reproductive activities of adults may be concentrated at burrows.<ref name=r8/> When pygmy rabbits can utilize sagebrush cover, burrow use is decreased. Pygmy rabbits use burrows more in the winter for thermal cover than at other times of the year.<ref name=r20/>

Burrows are usually located on slopes at the base of sagebrush plants, and face north to east. Tunnels widen below the surface, forming chambers, and extend to a maximum depth of about {{convert|1|m|ft|sp=us}}. Burrows typically have 4 or 5 entrances but may have as few as 2 or as many as 10.<ref name=r8/> In Oregon, pygmy rabbits inhabited areas where soils were significantly deeper and looser than soils at adjacent sites. Site selection was probably related to ease of excavation of burrows.<ref name=r17/> In areas where soil is shallow pygmy rabbits live in holes among volcanic rocks, in stone walls, around abandoned buildings, and in burrows made by badgers (''Taxidea taxus'') and marmots (''Marmota flaviventris'').<ref name=r8/><ref name=r2/>

Some researchers have found that pygmy rabbits never venture farther than {{convert|60|ft|m|sp=us}} from their burrows.<ref name=r2/> However, Bradfield<ref name=r2/> observed pygmy rabbits range up to {{convert|100|m|ft|sp=us}} from their burrows.

Some areas inhabited by pygmy rabbits are covered with several feet of snow for up to 2 or more months during the winter. During periods when the snow has covered most of the sagebrush, pygmy rabbits tunnel beneath the snow to find food. Snow tunnels are approximately the same height and width as burrows. They are quite extensive and extend from one sagebrush to another.<ref name=r8/><ref name=r2/> Above ground movement during the winter months is restricted to these tunnel systems.<ref name=r2/>

===Cover requirements===
Pygmy rabbits are restricted to areas with heavy shrub cover.<ref name=r8/><ref name=r4/> Pygmy rabbits are seldom found in areas of sparse vegetative cover and seem to be reluctant to cross open space.<ref name=r2/> In southeastern Idaho, woody cover and shrub height were significantly {{nobr|({{mvar|p}} < 0.01)}} greater on sites occupied by pygmy rabbits than on other sites in the same area.<ref name=r7/>

===Plant communities===
Pygmy rabbits are found primarily in big sagebrush (''[[Biology:Artemisia tridentata|Artemisia tridentata]]'') and rabbitbrush (''[[Biology:Chrysothamnus|Chrysothamnus]]'' spp.) dominated communities.<ref name=r2/><ref>{{cite journal|last1=Larrucea|first1=Eveline S.|last2=Brussard|first2=Peter F.|title=Habitat selection and current distribution of the pygmy rabbit in Nevada and California, USA|journal=Journal of Mammalogy|volume=89|pages=691–699|year=2008|issue=3|doi=10.1644/07-MAMM-A-199R.1|s2cid=55487275 |doi-access=}}</ref><ref name=r7/><ref name=r16>{{cite journal|author=Severaid, Joye Harold|year= 1950|title= The pigmy rabbit (''Sylvilagus idahoensis'') in Mono County, California|journal= Journal of Mammalogy|volume= 31|issue=1|pages=1–4|doi= 10.2307/1375469|jstor=1375469}}</ref><ref name=r18>{{cite journal | last1=Welch | first1=Bruce L. | last2=Wagstaff | first2=Fred J. | last3=Roberson | first3=Jay A. | title=Preference of Wintering Sage Grouse for Big Sagebrush | journal=Journal of Range Management | volume=44 | issue=5 | year=1991 | url=https://www.researchgate.net/publication/265152930 | doi=10.2307/4002745 | page=462| jstor=4002745| hdl=10150/644764 | hdl-access=free }}</ref> Pygmy rabbits are also found in areas where greasewood (''[[Biology:Sarcobatus|Sarcobatus]]'' spp.) is abundant.<ref name=r7/> Some woody species found on sites inhabited by pygmy rabbits in southeastern Idaho include big sagebrush, antelope bitterbrush (''[[Biology:Purshia tridentata|Purshia tridentata]]''), threetip sagebrush (''[[Biology:Artemisia tripartita|A. tripartita]]''), low rabbitbrush (''[[Biology:Chrysothamnus viscidiflorus|C. viscidiflorus]]''), gray horsebrush (''[[Biology:Tetradymia canescens|Tetradymia canescens]]''), and prickly phlox (''Leptodactylon pungens''). Grasses and forbs include thick spike wheatgrass (''Elymus lanceolatus''), plains reedgrass (''[[Biology:Calamagrostis montanensis|Calamagrostis montanensis]]''), sedges (''[[Biology:Carex|Carex]]'' spp.), prairie junegrass (''[[Biology:Koeleria macrantha|Koeleria macrantha]]''), Sandberg bluegrass (''[[Biology:Poa secunda|Poa secunda]]''), bluegrass (''[[Biology:Poa|Poa]]'' spp.), needle-and-thread grass (''Stipa comata''), western yarrow (''[[Biology:Achillea millefolium|Achillea millefolium]]''), rosy pussytoes (''[[Biology:Antennaria microphylla|Antennaria microphylla]]''), milkvetch (''[[Biology:Astragalus (plant)|Astragalus]]'' spp.), arrowleaf balsamroot (''[[Biology:Balsamorhiza sagittata|Balsamorhiza sagittata]]''), buckwheat (''[[Biology:Eriogonum|Eriogonum]]'' spp.), tailcup lupine (''[[Biology:Lupinus caudatus|Lupinus caudatus]]''), and phlox (''[[Biology:Phlox|Phlox]]'' spp.).<ref name=r7/> In the Upper Sonoran Desert pygmy rabbits occur in desert sagebrush associations dominated by big sagebrush and rabbitbrush with bitterbrush and sulphurflower (''[[Biology:Eriogonum umbellatum|Eriogonum umbellatum]] var. stellatum'').<ref name=r16/>

==Food habits==
The primary food of pygmy rabbits is big sagebrush, which may comprise up to 99% of the food eaten in the winter. Grasses and forbs are also eaten from mid- to late summer.<ref name=r8/><ref name=r2/><ref name=r7>{{cite journal |author1=Green, Jeffery S. |author2= Flinders, Jerran T. |year=1980 |title=Habitat and dietary relationships of the pygmy rabbit |journal=Journal of Range Management |volume=33 |issue=2 |pages=136–142 |doi=10.2307/3898429 |jstor=3898429 |hdl=10150/646516 |hdl-access=free}}</ref><ref name=r6>{{cite report |author1=Gates, Robert J. |author2=Eng, Robert L. |year=1984 |title=Sage grouse, pronghorn, and lagomorph use of a sagebrush-grassland burn site on the Idaho National Engineering Laboratory |editor=Markham, O. Doyle |series=Idaho National Engineering Laboratory |chapter=Radio Ecology and Ecology Programs 1983 Progress Reports |place=Idaho Falls, ID |publisher=U.S. Department of Energy / [[Organization:Radiological and Environmental Sciences Laboratory|Radiological and Environmental Sciences Laboratory]] |pages=220–235}}</ref> In Idaho, Gates & Eng (1984)<ref name=r6/> found that shrubs contributed 85.2% (unweighted mean) of pygmy rabbit diets from July to December. Shrub use was lowest in August (73.1%) and highest in December (97.9%). Big sagebrush was the most important shrub in the July to December diet (54.2%), followed by rubber rabbitbrush (''Chrysothamnus nauseosus'', 25.8%) and winterfat (''[[Biology:Krascheninnikovia lanata|Krascheninnikovia lanata]]'', 4.6%). Grasses comprised 10% of the July to December diet and were consumed mostly during July and August. Indian ricegrass (''[[Biology:Oryzopsis hymenoides|Oryzopsis hymenoides]]'') and needlegrass (''[[Biology:Stipa|Stipa]]'' spp.) were the most important grasses consumed. Forbs contributed 4.9% of the July to December diet.<ref name=r6/>

In southeastern Idaho, Green & Flinders (1980)<ref name=r7/> found that pygmy rabbits ate big sagebrush throughout the year, but in lesser amounts in summer (51% of diet) than in winter (99% of diet). Other shrubs in the area were consumed infrequently. Grass and [[Earth:Forb|forb]] consumption was relatively constant throughout the summer (39% and 10% of diet respectively) and decreased to a trace amount through fall and winter. Thickspike wheatgrass, bluebunch wheatgrass (''[[Biology:Pseudoroegneria spicata|Pseudoroegneria spicata]]''), and Sandberg bluegrass were preferred foods in the summer.<ref name=r7/>

==Predators==
Weasels (''[[Biology:Mustela|Mustela]]'' and ''[[Biology:Neogale|Neogale]]'' spp.) are the principal predators of pygmy rabbits. [[Biology:Coyote|Coyote]]s (''Canis latrans''), [[Biology:Red fox|red fox]]es (''Vulpes vulpes''), [[Biology:American badger|American badger]]s (''Taxidea taxus''), [[Biology:Bobcat|bobcat]]s (''Lynx rufus''), great horned owls (''Bubo virginianus''), and northern harriers (''Circus hudsonius'') also prey on pygmy rabbits.<ref name=r8>{{cite journal |author1=Green, Jeffrey S. |author2=Flinders, Jerran T. |year=1980 |title=''Brachylagus idahoensis'' |journal=Mammalian Species |issue=125 |pages=1–4 |doi=10.2307/3503856 |doi-access=free |jstor=3503856}}</ref><ref name=r2>{{cite thesis |author=Bradfield, Terry D. |year=1975 |title=On the behavior and ecology of the pygmy rabbit |place=Pocatello, ID |publisher=[[Organization:Idaho State University|Idaho State University]]}}</ref><ref name=r20/>

==Listing status==
In September&nbsp;2007, Judge Lodge<ref name=Lodge-2007/> of the U.S. District Court granted summary judgment to Western Watersheds Project, the litigant party, [[Social:Remand (court procedure)|remanding]] the United States Fish and Wildlife Service 90&nbsp;day finding denying conservationist parties' listing petition. The petition sought legal protection for pygmy rabbit as an [[Biology:Endangered species|endangered]] or [[Biology:Threatened species|threatened species]].<ref name=Lodge-2007>{{cite report |author=Lodge, E. |date=26 September 2007 |title=Standard for listing petitions & evaluation of threats to the pygmy rabbit |publisher=United States District Court for the District of Idaho |url=http://www.westernwatersheds.org/legal/07/pygmy/pygmysjorder.pdf |access-date=26 September 2007 |url-status=dead |archiveurl=https://web.archive.org/web/20110104114109/http://www.westernwatersheds.org/legal/07/pygmy/pygmysjorder.pdf |archive-date=4 January 2011}}</ref>

== References ==
{{reflist|25em}}

== Further information ==
<!-- Please move these into the text -->
{{refbegin|colwidth=25em|small=y}}
* {{cite report |title=Federal Register |year=2003 |publisher=United States Government. |url=http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=2003_register&docid=fr05mr03-13.pdf}}
* {{cite report |title=Columbia Basin Distinct population segment of the pygmy rabbit (''Brachylagus idahoensis'') |year=2004 |series=Recovery Outline |publisher=U.S. Fish and Wildlife Service |url=http://www.fws.gov/easternwashington/documents/CBPRrecoveryoutline.pdf}}
* {{cite news |title=Last-ditch effort to save endangered pygmy rabbits is nearing its end |date=2009-01-23 |df=dmy-all |newspaper=Wenatchee World |place=Wenatchee, WA |url=http://wenatcheeworld.com/article/20090123/NEWS04/701229924/1009/NEWS04 |archive-url=https://www.wenatcheeworld.com/news/local/last-ditch-effort-to-save-endangered-pygmy-rabbits-is-nearing-its-end/article_7e7f34fd-8308-502a-ae37-3cb3c91932fb.html |archive-date=2009-01-23}}
* {{cite news |title=Pygmy rabbits get last-minute reprieve |date=2010-03-12 |df=dmy-all |newspaper=Wenatchee World |place=Wenatchee, WA |url=https://www.wenatcheeworld.com/news/local/pygmy-rabbits-get-last-minute-reprieve/article_1f5c53ce-6e03-581a-b75e-bf461917eae1.html}}
{{refend}}

==External links==
*{{cite web |last=Allen |first=Harriet |title=WDFW - Pygmy Rabbit Recovery Plan |website=wdfw.wa.gov |date=1999-10-25 |url=http://wdfw.wa.gov/wlm/diversty/soc/pygmy_rabbit/ |archive-url=https://web.archive.org/web/20100721122655/http://wdfw.wa.gov/wlm/diversty/soc/pygmy_rabbit/ |archive-date=2010-07-21 |url-status=dead |ref=none}}
*{{cite web |last=Tucker |first=Abigail |title=Can Scientists Save the World's Tiniest Rabbit? |website=Smithsonian Magazine |date=2023-01-05 |url=https://www.smithsonianmag.com/science-nature/can-scientists-save-worlds-tiniest-rabbit-180981306/ |access-date=2023-01-08 |ref=none}}

{{Taxonbar|from=Q244194}}

[[Category:Leporidae]]
[[Category:ESA endangered species]]

{{Sourceattribution|Pygmy rabbit}}