Editing Lake Tahoe (section)

===Ecology===
{{main|Ecology of the Sierra Nevada}}[[Image:Sockeye salmon jumping over beaver dam Lake Aleknagik, AK Kristina Ramstad 1997.jpg|thumb |upright |[[Sockeye salmon]] (''[[Oncorhynchus nerka]]'') jumping a [[beaver dam]] |right]]
[[File:Broken beaver dam on Blackwood Creek June 2014.jpg|thumb|right |200px |Damaged [[North American beaver|beaver]] dam on [[Blackwood Creek (California)|Blackwood Creek]]. Beaver dams are easily crossed by [[cutthroat trout|trout]] and their ponds may serve as critical breaks for wildfires.<ref>{{cite journal |title=Do Beaver Dams Impede the Movement of Trout? |author=Ryan L. Lokteff  |author2=Brett B. Roper |author3=Joseph M. Wheaton |name-list-style=amp |date=2013 |journal=Transactions of the American Fisheries Society |volume=142 |issue=4 |pages=1114–25 |url=http://etal.usu.edu/Downloads/FactSheets/FactSheet_TempleForkLokteffFINAL_Flattened.pdf |access-date=June 17, 2014 |doi=10.1080/00028487.2013.797497|bibcode=2013TrAFS.142.1114L }}</ref><ref>{{cite book |title=Three Against the Wilderness |author=Eric Collier |year=1959 |publisher=Touchwood |location=Victoria, British Columbia |page=288 |isbn= 978-1-894898-54-6 }}</ref>]]
Vegetation in the basin is dominated by a mixed conifer forest of [[jeffrey pine]] (''Pinus jeffreyi''), [[lodgepole pine]] (''P. contorta''), [[white fir]] (''Abies concolor''), [[red fir]] (''A. magnifica''), [[sugar pine]] (''P. lambertiana''), [[California incense-cedar]] (''Calocedrus decurrens''), [[ponderosa pine]] (''P. ponderosa''), and [[western white pine]] (''P. monticola'').<ref>{{cite web|url=http://www.northstarattahoe.com/info/ski/media/tahoe_environment.asp |archive-url=https://web.archive.org/web/20120119180552/http://www.northstarattahoe.com/info/ski/media/tahoe_environment.asp |archive-date=January 19, 2012 |title=Trees Indigenous to Lake Tahoe |access-date=October 31, 2008 |publisher=Northstar-at-Tahoe Resort |url-status=dead }}</ref> The basin also contains significant areas of [[wet meadow]]s and [[riparian]] areas, dry [[meadow]]s, brush fields (with ''[[Arctostaphylos]]'' and ''[[Ceanothus]]'') and rock [[outcrop]] areas, especially at higher elevations. ''Ceanothus'' is capable of [[Nitrogen fixation|fixing nitrogen]], but [[Grey Alder|mountain alder]] (''Alnus tenuifolia''), which grows along many of the basin's streams, springs and seeps, fixes far greater quantities, and contributes measurably to nitrate-N concentrations in some small streams. The beaches of Lake Tahoe are the only known habitat for the rare [[Rorippa subumbellata|Lake Tahoe yellowcress]] (''Rorippa subumbellata''), a plant which grows in the wet sand between low- and high-water marks.<ref>{{cite web |url=http://www.natureserve.org/explorer/servlet/NatureServe?searchName=Rorippa+subumbellata |title=The Nature Conservancy: ''Rorippa subumbellata'' |website=Natureserve |access-date=November 15, 2011 |archive-date=August 17, 2005 |archive-url=https://web.archive.org/web/20050817024413/http://www.natureserve.org/explorer/servlet/NatureServe?searchName=Rorippa+subumbellata |url-status=dead }}</ref> Vegetation in the lake itself formerly consisted of native ''[[Chara (alga)|Chara]]'' and ''[[Gomphoneis]]'' algae and [[Ceratophyllum demersum|coontail]] (''Ceratophyllum demersum''), but the later introduction of [[Potamogeton crispus|curlyleaf pondweed]] (''Potamogeton crispus''), [[Myriophyllum spicatum|Eurasian watermilfoil]] (''Myriophyllum spicatum''), and ''[[Zygnema]]'' and ''[[Cladophora]]'' algae has transformed the nearshore environment.<ref name="FISHBIO-2017">{{Cite web|title=The Lake Tahoe Takeover |date= May 17, 2017|publisher= FISHBIO Fisheries Research, Monitoring, and Conservation|url=https://fishbio.com/field-notes/population-dynamics/lake-tahoe-takeover|access-date=July 17, 2020|language=en-US}}</ref>

Native fish of the lake include [[Lahontan cutthroat trout]] (''Oncorhynchus clarki henshawi''), [[mountain whitefish]] (''Prosopiurm williamsoni''), [[Speckled dace|Lahontan speckled dace]] (''Rhinichthys osculus robustus''), [[Lahontan redside]] (''Rhinichthys egregious''), [[Tui chub|Lahontan Lake tui chub]] (''Siphateles bicolor pectinifer''), [[Tahoe sucker]] (''Catostomus tahoensis''), [[Mountain sucker|Lahontan mountain sucker]] (''Catostomus platyrhynchus lahontan''), and [[Paiute sculpin]] (''Cottus beldingi''). Most of these fish populations have been significantly reduced due to the introduction of nonnative fish, [[Corbicula fluminea|Asian clam]] (''Corbicula fluminea''), and [[Mysida|mysid shrimp]]. Competition from introduced fish led cutthroat trout to be completely [[Local extinction|extirpated]] from the lake in the early 20th century until [[Species reintroduction|reintroduction]] efforts started in 2019.<ref name="NDOW-2020">{{Cite web|title=Nevada Department of Wildlife|url=http://www.ndow.org/Bodies_Of_Water/Lake_Tahoe/|access-date=July 17, 2020|website=Ndow.org|archive-date=November 18, 2020|archive-url=https://web.archive.org/web/20201118135058/http://www.ndow.org/Bodies_Of_Water/Lake_Tahoe/|url-status=dead}}</ref><ref>{{Cite web|date=May 28, 2020|title=More Than 4,600 Lahontan Cutthroat Trout Released into Native Lake Tahoe|url=https://activenorcal.com/more-than-4600-lahontan-cutthroat-trout-released-into-native-lake-tahoe/|access-date=July 17, 2020|website=Active NorCal|language=en-US}}</ref><ref name="FISHBIO-2017" />

Introduced fish species include [[lake trout]] (''Salvelinus namaycush''<u>),</u> [[rainbow trout]] (''Oncorhynchus mykiss gairdneri''), [[sockeye salmon]] (''Oncorhyncus nerka''), [[brown trout]] (''Salmo trutta''), [[brook trout]] (''Salvelinus fontinalis''), [[common carp]] (''Cyprinus carpio''), [[golden shiner]] (''Notemigonus crysoleucas''), [[Mosquitofish|western mosquitofish]] (''Gambusia affinis''), [[bluegill]] (''Lepomis macrochirus''), [[Black crappie|black]] (''Pomoxis nigromaculatus'') and [[White crappie|white]] (''P. annularis'') [[crappie]], [[Largemouth bass|largemouth]] (''Micropterus salmoides'') and [[Smallmouth bass|smallmouth]] (''Micropterus dolomieu'') [[Micropterus|bass]], and [[brown bullhead]] (''Ameiurus nebulosus'').<ref name="FISHBIO-2017" /><ref name="NDOW-2020" /> Each autumn, from late September through mid-October, mature sockeye salmon transform from silver-blue color to a fiery [[vermilion]], and run up Taylor Creek, near South Lake Tahoe. As spawning season approaches the fish acquire a humpback and protuberant jaw. After spawning they die and their carcasses provide a feast for gatherings of [[American mink|mink]] (''Neogale vison''), [[American black bear|bear]]s (''Ursus americanus''), and [[bald eagle]]s (''Haliaeetus leucocephalus''). The non-native salmon were transplanted from the [[Pacific Ocean|North Pacific]] to Lake Tahoe in 1944.<ref>{{cite journal |title=Tahoe's drama of the kokanee |author=Marcia Williamson |journal=Sunset Magazine |date=Oct 1992 |url=https://www.questia.com/read/1G1-12884197 |access-date=May 8, 2010 }}</ref>

[[North American beaver]] (''Castor canadensis'') were [[Beaver in the Sierra Nevada|re-introduced to the Tahoe Basin]] by the [[California Department of Fish and Wildlife]] and the [[United States Forest Service|U.S. Forest Service]] between 1934 and 1949. Descended from no more than nine individuals, 1987 beaver populations on the upper and lower [[Truckee River]] had reached a density of 0.72 colonies (3.5 beavers) per kilometer.<ref>{{cite journal|title=Beaver Distribution in the Truckee River Basin, California |last1=Beier|first1=P|last2=Barrett|first2=RH |journal=California Fish and Game |year=1989 |url=http://oak.ucc.nau.edu/pb1/vitae/Beier-Barrett.1987.CDFG_Beaver.pdf |access-date=January 17, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20110720012004/http://oak.ucc.nau.edu/pb1/vitae/Beier-Barrett.1987.CDFG_Beaver.pdf |archive-date=July 20, 2011 }}</ref> At the present time beaver have been seen in Tahoe Keys, [[Taylor Creek (Lake Tahoe)|Taylor Creek]], Meeks Creek at [[Meeks Bay]] on the western shore, and [[Kings Beach, California|Kings Beach]] on the north shore, so the descendants of the original nine beavers have apparently migrated around most of Lake Tahoe.<ref>{{cite web |title=The Beavers of the Truckee River |publisher=Tahoe Arts and Mountain Culture |url=http://www.tahoeculture.com/green-tahoe/eco-tips/the-beavers-of-the-truckee-river-going-to-town/ |date=July 20, 2009 |access-date=August 16, 2010 |archive-url=https://web.archive.org/web/20110609011329/http://www.tahoeculture.com/green-tahoe/eco-tips/the-beavers-of-the-truckee-river-going-to-town/ |archive-date=June 9, 2011 |url-status=dead }}</ref><ref name=Kings>{{cite news|title=This is Wildlife Management in the 21st century? |author=Keaven Van Lom |publisher=Moonshine Ink |date=January 16, 2010 |url=http://moonshineink.com/articles.php/70/1618 |archive-url=https://web.archive.org/web/20120303135432/http://moonshineink.com/articles.php/70/1618 |archive-date=March 3, 2012 |access-date=August 16, 2010 |url-status=dead }}</ref> Recently novel physical evidence has demonstrated that beaver were native to the Sierra until at least the mid-nineteenth century, via radiocarbon dating of buried beaver dam wood uncovered by deep channel incision in the [[Feather River]] watershed.<ref>{{cite journal |title=Novel physical evidence that beaver historically were native to the Sierra Nevada |author=James, C. D. |author2=Lanman, R. B. |journal=California Fish and Game |date=Spring 2012 |volume=98 |number=2 |pages=129–32 |url=https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=67452&inline=1 |access-date=June 17, 2014 }}</ref> That report was supported by a summary of indirect evidence of beaver including reliable observer accounts of beaver in multiple watersheds from the northern to the southern Sierra Nevada, including its eastern slope.<ref>{{cite journal |title=The historical range of beaver in the Sierra Nevada: a review of the evidence |author=R. B. Lanman |author2=H. Perryman |author3=B. Dolman|author4=Charles D. James |journal=California Fish and Game |date=Spring 2012 |volume=98 |number=2 |pages=65–80 |url=https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=67444&inline=1 |access-date=June 17, 2014}}</ref> A specific documented record of beaver living historically in Lake Tahoe's [[North Canyon Creek]] watershed above [[Glenbrook, Nevada|Glenbrook]] includes a description of [[Spooner Lake|Spooner Meadow]] rancher Charles Fulstone hiring a caretaker to control the beaver population in the early 20th century.<ref name=Restoration>{{cite report|title=North Canyon Creek Restoration Project: Phase I Final Report|author1=((2ndNature))|author2=((Huffman & Carpenter, Inc.))|name-list-style=amp|publisher=U.S. Army Corps of Engineers Sacramento District|date=April 2010|url=http://www.2ndnaturellc.com/wp-content/uploads/2011/12/NCC_Final.pdf|access-date=September 6, 2016|archive-date=October 11, 2016|archive-url=https://web.archive.org/web/20161011073300/http://www.2ndnaturellc.com/wp-content/uploads/2011/12/NCC_Final.pdf|url-status=dead}}</ref> A recent study of Taylor Creek showed that beaver dam removal decreased wetland habitat, increased stream flow, and increased total phosphorus pollutants entering Lake Tahoe – all factors which negatively impact the clarity of the lake's water.<ref name=Muskopf>{{cite thesis |title=The Effect of Beaver (Castor canadensis) Dam Removal on Total Phosphorus Concentration in Taylor Creek and Wetland, South Lake Tahoe, California |author=Sarah Muskopf |publisher=Humboldt State University, Natural Resources |date=October 2007 |hdl=2148/264 }}</ref> In addition, beaver dams located in [[Ward Creek (Lake Tahoe)|Ward Creek]], located on the west shore of Lake Tahoe, were also shown to decrease nutrients and sediments traveling downstream.<ref name=Muskopf />

The lake's low temperatures and extreme depth can slow the decomposition rate of organic matter. For example, the almost perfectly preserved body of a diver was found at a depth of {{convert|300|ft|m|-1}} 17 years after he went missing.<ref>{{cite news|url=https://www.latimes.com/archives/la-xpm-2011-aug-09-la-me-missing-diver-20110809-story.html|title=At Lake Tahoe, a scuba diver's body is recovered after 17 years|newspaper=Los Angeles Times|date=August 9, 2011}}</ref>