Editing Clark's nutcracker (section)

==Food==
[[File: Clark's Nutcracker. Nucifraga columbiana - Flickr - gailhampshire.jpg|thumb|Clark's nutcracker feeding on seeds of pines]]
The most important food resources for this species are the seeds of [[pine]]s (''Pinus'' sp.), principally the two cold-climate (high altitude) species of [[Pinus classification|white pine]] (''Pinus'' subgenus ''Strobus'') with large seeds ''[[Whitebark pine|P. albicaulis]]'' and ''[[Limber pine|P. flexilis]]'', but also using other high-altitude species like ''[[Foxtail pine|P. balfouriana]], [[Bristlecone pine|P. longaeva]]'' and ''[[Western white pine|P. monticola]]''. During [[Altitudinal migration|migrations to lower altitudes]], it also extensively uses the seeds of [[pinyon pine]]s. The isolated Cerro Potosí population is strongly associated with the local endemic [[Potosi pinyon]] (''Pinus culminicola)''. All Clark's nutcrackers have a [[sublingual pouch]] capable of holding around 50–150 seeds, depending on the size of the seeds;<ref name="Tomback">{{cite book|last=Tomback|first=DF|author-link=Diana Tomback|year=1998|chapter=Clark's Nutcracker (''Nucifraga columbiana'')|editor1-first=A|editor1-last=Poole|editor2-first=F|editor2-last=Gill|title=The Birds of North America|number=331|publisher=The Birds of North America, Inc.|location=Philadelphia}}</ref> the pouch greatly enhances the birds' ability to transport and store seeds.

Clark's nutcrackers store seeds, usually in the ground for later consumption, in caches of 1–15 seeds (average of 3–4 seeds).<ref name="Tomback" /> Depending on the cone crop as well as the tree species, a single Clark's nutcracker can cache as many as 98,000 seeds per season.<ref>{{cite journal|last1=Hutchins|first1=HE|first2=FM|last2=Lanner|year=1982|title=The central role of Clark's nutcracker in the dispersal and establishment of whitebark pine|journal=Oecologia|volume=55|issue=2 |pages=192–201|doi=10.1007/BF00384487 |pmid=28311233 |bibcode=1982Oecol..55..192H |s2cid=16214504 }}</ref> The birds regularly store more than they actually need as insurance against seed theft by other animals ([[squirrel]]s, etc.), as well as low availability of alternative foods; this surplus seed is left in the cache, and may be able to germinate and grow into new trees, if the conditions are right. Through this activity of caching and over-storing, the bird is perpetuating its own habitat. Closely tied in with this storage behavior is the bird's remarkable long-term spatial memory; they are able to relocate caches of seeds with great accuracy, even nine months later,<ref>{{cite journal|last=Tomback|first=DF|author-link=Diana Tomback|year=1978|title=Foraging strategies of Clark's Nutcracker|journal=Living Bird|volume=16|pages=123–161}}</ref> and even when the cache sites are buried under up to a meter (3&nbsp;ft) of snow. Its powers of memory exemplify the high intelligence of the Corvidae.  Clark's nutcrackers are known for storing and recovering large numbers of seed caches that are critical for winter survival. Short-term memory tasks reveal that nutcrackers can remember spatial information better than visual information. It was demonstrated that the cache recovery ability of Clarks nutcracker is derived from a memory system that has evolved differently for storing spatial information.<ref>{{Cite journal|last1=Qadri|first1=Muhammad A. J.|last2=Leonard|first2=Kevin|last3=Cook|first3=Robert G.|last4=Kelly|first4=Debbie M.|date=2018-12-01|title=Examination of long-term visual memorization capacity in the Clark's nutcracker (Nucifraga columbiana)|journal=Psychonomic Bulletin & Review|language=en|volume=25|issue=6|pages=2274–2280|doi=10.2307/1367199|pmid=29450792|issn=1531-5320|doi-access=free}}</ref>

[[File: Clark's Nutcracker with wings out, landing on a rock.JPG|thumb|Clark's nutcracker landing, [[Mount Hood]], Oregon]]
The diet also includes a wide range of [[insect]] prey, berries and other fruits, small [[mammal]]s, including ground squirrels and voles, nestling birds, amphibians, and occasionally flesh from carcasses.<ref>{{Cite journal|last1=Mulder|first1=Barry S.|last2=Schultz|first2=Brian B.|last3=Sherman|first3=Paul W.|date=1978-12-01|title=Predation on vertebrates by Clark's Nutcrackers|journal=Condor|language=en|volume=80|issue=4|pages=449-451|doi=10.3758/s13423-018-1439-4}}</ref> Eggs and nestlings are sometimes devoured, and [[peanut]]s and suet have become a favorite at [[Bird feeder|bird tables]]. Food is taken both from the ground and from trees, where the nutcrackers are very agile among the branches. The birds are able to extract food by clasping pine cones in such a way that the cones are held between one or both feet. The birds then hack the cones open with their strong bills. Rotten logs are also hacked into in order to locate large beetle grubs, and animal dung may be flipped over in search of insects. Clark's nutcrackers can also be opportunistic feeders in developed areas, and are known to some as "camp robbers".