View source for Lake Victoria

{{other places}}
{{multiple issues|
{{primary sources|date = December 2024}}
{{format citations|date = December 2024}}
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{{short description|Lake in East-central Africa}}
{{Use dmy dates|date=September 2019}}
{{Infobox body of water
| native_name        = {{native name list |tag1=Sw|name1=Ukerewe |tag2=lg|name2='Nnalubaale |tag3=rw|name3=Nyanza |tag4=luo|name4=Nam Lolwe}}
| location           = [[African Great Lakes]]
| image              = ISS042-E-263206 - View of Earth.jpg
| alt                = see caption
| caption            = Lake Victoria partially obscured by clouds taken on the [[International Space Station]]
| image_bathymetry   = 
| caption_bathymetry = Lake Victoria is the largest lake in Africa.
| coords             = {{Coord|1|S|33|E|type:waterbody_scale:3000000|display=inline,title}}
| outflow            = [[White Nile]]
| inflow             = [[Kagera River]]
| catchment          = {{convert|169858|km2|sqmi|abbr=on}}<br />{{convert|229815|km2|sqmi|abbr=on}} basin <ref name="auto">{{Cite journal | doi=10.7910/DVN/Z5RMYD|title = Basin, Lake Victoria Watershed (inside), vector polygon, ~2015|last1 = Hamilton|first1 = Stuart (Salisbury University)| year=2016| journal=Harvard Dataverse|type = Data Set}}</ref>
| basin_countries    = [[Burundi]], [[Kenya]], [[Rwanda]], [[Tanzania]], and [[Uganda]]<ref name="auto" />
| length             = {{convert|359|km|mi|abbr=on}}<ref name="auto1">{{Cite journal | doi=10.7910/DVN/PWFW26|title = Shoreline, Lake Victoria, vector polygon, ~2015|last1 = Hamilton|first1 = Stuart (Salisbury University)| year=2016| journal=Harvard Dataverse|type = Data Set}}</ref>
| width              = {{convert|337|km|mi|abbr=on}}<ref name="auto1" />
| area               = {{convert|59947|km2|sqmi|abbr=on}}<ref name="auto2">{{Cite book | doi=10.7910/DVN/FVJJ4A|title = Lake Victoria Statistics from this Dataverse|last1 = Hamilton|first1 = Stuart| chapter=Earth and Environmental Sciences | year=2018| publisher=Harvard Dataverse|type = Data Set}}{{full|date = December 2024}}</ref>{{page needed|date = December 2024}}
| depth              = {{convert|40.4|m|ft|abbr=on}}<ref name="auto2" />
| max-depth          = {{convert|81|m|ft|abbr=on}}<ref name="auto2" />
| volume             = {{convert|2424|km3|mi3|abbr=on}}<ref name="auto2" />
| shore              = {{convert|7142|km|mi|abbr=on}}<ref name="auto2" />
| elevation          = {{convert|1135|m|ft|abbr=on}}<ref>[http://dahiti.dgfi.tum.de/en/2/ ''Database for Hydrological Time Series of Inland Waters (DAHITI) – Victoria, Lake''], retrieved 20 April 2017.</ref>
| residence_time     = 
| islands            = 985 ([[Ukerewe Island]], Tanzania;[[Ssese Islands]],<ref name="auto2" /> Uganda; [[Maboko Island]], Kenya)<ref>For a comprehensiwe list of these islands, see: [[:sw:Ziwa Viktoria]]</ref>
| islands_category   = Islands of Lake Victoria
| cities             = {{Plainlist}}
* [[Bukoba]], Tanzania
* [[Mwanza]], Tanzania
* [[Musoma]], Tanzania
* [[Kisumu]], Kenya
* [[Kendu Bay]], Kenya
* [[Homa Bay]], Kenya
* [[Kampala]], Uganda
* [[Entebbe]], Uganda
* [[Jinja, Uganda|Jinja]], Uganda
{{Endplainlist}}
<!--      Map      -->| pushpin_map        = Africa
| pushpin_label_position = 
| pushpin_map_alt    = Location of Lake Victoria in Africa.
| pushpin_map_caption = <!--   Below       -->
| website            = 
| reference          = 
| name               = Lake Victoria
}}
[[File:Victoria Nyanza.jpg|thumb|upright=1.4|Victoria Nyanza. The black line indicates Stanley's route.]]

'''Lake Victoria''' is one of the [[African Great Lakes]].<ref>{{Cite web |title=Lake Victoria {{!}} AGLI |url=https://www.africangreatlakesinform.org/page/lake-victoria |access-date=2025-07-05 |website=www.africangreatlakesinform.org}}</ref> With a surface area of approximately {{cvt|59947|km2|sqmi}},<ref>{{Cite journal |last=Stuart |first=Hamilton |date=2016-10-05 |title=Shoreline, Lake Victoria, vector polygon, ~2015 |language=en |doi=10.7910/dvn/pwfw26 |journal=Harvard Dataverse |type=Data Set}}</ref><ref name="auto3">{{Cite book |last=Stuart |first=Hamilton |date=2018-11-13 |title=Lake Victoria Statistics from this Dataverse |chapter=Earth and Environmental Sciences |language=en |doi=10.7910/dvn/fvjj4a |publisher=Harvard Dataverse |type=Data Set}}{{full|date = December 2024}}</ref>{{page needed|date = December 2024}} Lake Victoria is Africa's largest lake by area, the world's largest [[tropics|tropical]] lake,<ref>{{cite web |url=http://www.eoearth.org/view/article/154134/ |title=Lake Victoria |first=Peter |last=Saundry}}</ref> and the world's second-largest [[fresh water]] lake by surface area after [[Lake Superior]] in North America.<ref>{{cite web |url=https://www.britannica.com/place/Lake-Victoria |title=Lake Victoria |website=[[Encyclopædia Britannica]]}}</ref> In terms of volume, Lake Victoria is the world's [[list of lakes by volume|ninth-largest continental lake]], containing about {{cvt|2424|km3|acre ft}} of water.<ref name="auto3" /><ref name="auto4">{{Cite journal |last1=Stuart |first1=Hamilton |last2=Taabu |first2=Anthony Munyaho |last3=Noah |first3=Krach |last4=Sarah |first4=Glaser |date=2018-05-17 |title=Bathymetry TIFF, Lake Victoria Bathymetry, raster, 2017, V7 |language=en |doi=10.7910/dvn/soeknr |journal=Harvard Dataverse |type=Data Set}}</ref> Lake Victoria occupies a shallow [[Depression (geology)|depression]] in Africa. The lake has an average depth of {{cvt|40|m|ft}} and a maximum depth of {{cvt|80 - 81|m|ft}}.<ref name="auto3"/><ref name="auto4"/><ref name="UNEP99">United Nations, ''Development and Harmonisation of Environmental Laws Volume 1: Report on the Legal and Institutional Issues in the Lake Victoria Basin'', United Nations, 1999, page 17</ref> Its [[drainage basin|catchment area]] covers {{cvt|169858|km2|sqmi}}.<ref>{{Cite journal |journal=Harvard Dataverse |last=Stuart |first=Hamilton |date=2017-11-12 |title=Basin, Lake Victoria Watershed (inside), vector polygon, ~2015 |language=en |doi=10.7910/dvn/z5rmyd |type=Data Set}}</ref>  The lake has a shoreline of {{cvt|7142|km|mi}} when digitized at the 1:25,000 level,<ref>{{Cite book |title=Shoreline, Lake Victoria, vector line – 2015 – LakeVicFish Dataverse |doi=10.7910/dvn/5y5ivf|date=2016-10-11 |last=Hamilton |first=Stuart |chapter=Earth and Environmental Sciences |publisher=Harvard Dataverse |type=Data Set}}{{full|date = December 2024}}</ref>{{page needed|date = December 2024}} with islands constituting 3.7% of this length.<ref name="Hickling61">{{cite book |author=Hickling, C. F.  |year=1961 |title=Tropical Inland Fisheries |url=https://archive.org/details/tropicalinlandfi0000hick |url-access=registration |location=London |publisher=[[Longmans]]}}{{full|date = December 2024}}</ref>{{page needed|date = December 2024}} 

The lake's area is divided among three countries: [[Tanzania]] occupies 49% ({{cvt|33,700|km2|sqmi}}),  [[Uganda]] 45% ({{cvt|31,000|km2|sqmi}}), and [[Kenya]] 6% ({{cvt|4,100|km2|sqmi}}).<ref>J. Prado, R.J. Beare, J. Siwo Mbuga & L.E. Oluka, 1991. ''A catalogue of fishing methods and gear used in Lake Victoria''. UNDP/FAO Regional Project for Inland Fisheries Development (IFIP), FAO RAF/87/099-TD/19/91 (En). Rome, Food and Agricultural Organization.</ref>

The lake is home to many species of fish which live nowhere else, especially [[cichlid]]s. [[Invasive species|Invasive]] fish, such as the [[Nile perch]], have driven many [[Endemism|endemic]] species to [[extinction]].

==Names==
Though having multiple local language names ({{langx|sw|Ukerewe}}; {{langx|luo|Nam Lolwe}}; {{langx|lg|'Nnalubaale}}; {{langx|rw|Nyanza}}),<ref name="WDL1">{{cite web |title=The Victoria. The Land, the Races and their Customs, with Specimens of Some of the Dialects |url=http://www.wdl.org/en/item/2557 |publisher=[[World Digital Library]] |access-date=18 February 2013 |year=1899 |archive-url=https://web.archive.org/web/20160529091640/https://www.wdl.org/en/item/2557/ |archive-date=29 May 2016 }}</ref><ref>{{cite web
 |url=https://ntz.info/gen/n01545.html
 |title=Lake Ukerewe
 |website=nTZ: An Information Resource for Northern Tanzania
 |publisher=David Marsh
 |access-date=17 October 2020
 }}</ref> the lake was renamed after [[Queen Victoria]] by the explorer [[John Hanning Speke]], the first [[British people|Briton]] to document it in 1858, while on an expedition with [[Richard Francis Burton]].<ref>{{cite news |title=How Feud Wrecked the Reputation of Explorer Who Discovered Nile's Source |url=https://www.theguardian.com/books/2011/sep/11/burton-speke-african-exploration-nile |newspaper=[[The Guardian]] |access-date=29 December 2013 |first=Dalya |last=Alberge |date=11 September 2011}}</ref><ref>{{cite book |last=Moorehead |first=Alan |title=The White Nile |chapter = Zanzibar 1856, etc. | chapter-url=https://archive.org/details/whitenile0000moor |chapter-url-access=registration |year=1960 | location = New York, NY | publisher=Harper & Row |isbn=978-0-06-095639-4 }}{{full|date = December 2024}} Information is drawn from Part One, Chapters 1–7 (pp. 9–134).{{page needed|date = December 2024}}</ref>{{page needed|date = December 2024}} 

==Geology==
{{Refimprove science | section | date = December 2024}}
[[File:Topography of Lake Victoria.png|thumb|Topographical map of Lake Victoria]]
Photojournalist [[John Reader]], writing in his Alan Paton Literary Award-winning ''Africa: A Biography of a Continent'',<ref>{{cite news | author = The Times Staff | date= 26 February 2009  | orig-date= 4 June 2007  | title = Previous Winners of the Alan Paton Award and the Sunday Times Fiction Prize | newspaper = The Times (Johannesburg) | url = http://www.thetimes.co.za/SpecialReports/BookAwards/Article.aspx?id=482608 | access-date = 26 December 2024 | archive-url = https://web.archive.org/web/20090226215141/http://www.thetimes.co.za/SpecialReports/BookAwards/Article.aspx?id=482608 | archive-date = 2009-02-26 | quote = Previous Literary Awards winners / Previous Winners of the Alan Paton Award / 1998: Africa: A Biography of a Continent by John Reader, published by Penguin SA }}</ref> describes Lake Victoria as being relatively geologically young at about 400,000-years old—having been formed as westward-flowing rivers were backed up "when a fractured block of the Earth's crust tilted along the line of the Great Rift Valley, raising its western edge".<ref name="Reader">{{cite book | author = Reader, John | date = 2001 | orig-date = 1998 | title=Africa: A Biography of a Continent | location=Washington, DC | publisher=[[National Geographic Society]] | via = Archive.org | isbn=978-0-7922-7681-4 | pages=227f | url-access=registration | url=https://archive.org/details/africa0000read | access-date = 26 December 2024}}</ref>{{better source|date = December 2024}}<!--THIS IS A POPULAR WORK, AND NOT A SCHOLARLY GEOLOGICAL SOURCE.--> A primary study, attempting "fluvial differentiation of the basin of Lake Victoria", draws several relevant tentative conclusions. First, during the [[Miocene]] era, what is now the catchment area of the lake was on the western side of an uplifted area that functioned as a continental divide, with streams on the western side flowing into the [[Congo River]] basin and streams on the eastern side flowing to the Indian Ocean. Second, as the [[East African Rift]] System formed, the eastern wall of the [[Albertine Rift]] (or Western Rift) rose, gradually reversing the drainage towards what is now Lake Victoria. Third, the opening of the main East African Rift and the Albertine Rift downwarped the area between them as the rift walls rose, creating the current Lake Victoria [[Structural basin|basin]].<ref>{{Cite journal |last=Ouma |first=J. P. B. M. |date=1970 |title=Fluvial Differentiation in the Basin of Lake Victoria |journal=Journal of Hydrology (New Zealand) |volume=9 |issue=2 |pages=221–223 |jstor=43944206 | quote = On the basis each of catchment texture, catchment shape, and stream length propagation ratio, fluvial differentiation of the basin of Lake Victoria is attempted.}}{{primary source inline|date = December 2024}}</ref>{{primary source inline|date = December 2024}} 

During its geological history, Lake Victoria went through changes ranging from its present shallow depression, through to what may have been a series of much smaller lakes.<ref name="Hickling61"/>{{page needed|date = December 2024}}{{update after|2024|12|27}} [[core sample|Geological cores]] taken from its bottom show Lake Victoria has dried up completely at least three times since it formed.<ref name="Reader"/>{{better source|date = December 2024}} These drying cycles are probably related to [[Quaternary glaciation|past ice ages]], which were times when [[precipitation (meteorology)|precipitation]] declined globally.<ref name="Reader"/>{{better source|date = December 2024}} According to another primary source, Lake Victoria last dried out about 17,300 years ago, and it refilled 14,700 years ago<ref name="Verheyen2003">{{cite journal |author=Verheyen, Erik; Salzburger, Walter; Snoeks, Jos & Meyer, Axel |year=2003 |title=Origin of the Superflock of Cichlid Fishes from Lake Victoria, East Africa |journal=[[Science (journal)|Science]] |volume=300 |issue=5617 |pages=325–329 |doi=10.1126/science.1080699 |pmid=12649486 |bibcode=2003Sci...300..325V |s2cid=84478005 |url=http://nbn-resolving.de/urn:nbn:de:bsz:352-opus-32706 |doi-access=free }}</ref>{{primary source inline|date = December 2024}}—as the [[African humid period]] began.<ref>{{cite journal |last1=deMenocal |first1=Peter |last2=Ortiz |first2=Joseph |last3=Guilderson |first3=Tom |last4=Adkins |first4=Jess |last5=Sarnthein |first5=Michael |last6=Baker |first6=Linda |last7=Yarusinsky |first7=Martha |title=Abrupt Onset and Termination of the African Humid Period |journal=Quaternary Science Reviews |date=January 2000 |volume=19 |issue=1–5 |pages=347–361 |doi=10.1016/S0277-3791(99)00081-5  |language=en |issn=0277-3791 |bibcode=2000QSRv...19..347D}}</ref>

==Hydrology and limnology==
Lake Victoria receives 80 percent of its water from direct rainfall.<ref name="Hickling61"/>{{page needed|date = December 2024}} Average evaporation on the lake is between {{convert|2.0| and |2.2|m}} per year, almost double the precipitation of [[riparian]] areas.<ref>{{cite book|author=Ominde, Simeon H. |year=1971|chapter=Rural Economy in West Kenya| chapter-url=https://books.google.com/books?id=WgamvCA98usC&pg=PA220 |title=Studies in East African Geography and Development| pages=207–29| editor=S.H. Ominde|location=London|publisher=Heinemann Educational |isbn=978-0-520-02073-3}}</ref> Lake Victoria receives its water additionally from rivers, and thousands of small [[stream]]s. The [[Kagera River]] is the largest river flowing into this lake, with its [[river delta|mouth]] on the lake's western shore. Lake Victoria is drained solely by the [[Nile|Nile River]] near [[Jinja, Uganda|Jinja]], Uganda on the lake's northern shore.<ref name="Fishery">{{cite book|url=https://books.google.com/books?id=WLZRxM9vfXoC&pg=PA291|title=Source Book for the Inland Fishery Resources of Africa, Issue 18, Volume 1|last1=vanden Bossche|first1=J.-P.|last2=Bernacsek|first2=G.M.|publisher=[[Food and Agriculture Organization]], [[United Nations]]|year=1990|isbn=978-92-5-102983-1|page=291|access-date=4 January 2016}}</ref>
[[File:Rift en.svg|thumb|right|Lake Victoria and the [[Great Rift Valley]]]]
{{More citations needed|paragraph|date=June 2017}}
In the Kenya sector, the main influent rivers are the [[Sio River|Sio]], [[Nzoia]], [[Yala River|Yala]], [[Nyando River|Nyando]], [[Sondu Miriu]], [[Mogusi]], and [[Migori]]. The only outflow from Lake Victoria is the Nile River, which exits the lake near Jinja, Uganda. In terms of contributed water, this makes Lake Victoria the principal source of the longest branch of the Nile. However, the most distal source of the Nile Basin, and therefore the ultimate [[Nile#Sources|source of the Nile]], is more often considered to be one of the tributary rivers of the Kagera River (the exact tributary remains undetermined), and which originates in either [[Rwanda]] or [[Burundi]]. The uppermost section of the Nile is generally known as the Victoria Nile until it reaches [[Lake Albert (Africa)|Lake Albert]]. Although it is a part of the same river system known as the [[White Nile]] and is occasionally referred to as such, strictly speaking this name does not apply until after the river crosses the Uganda border into South Sudan to the north.

The lake exhibits [[Eutrophication|eutrophic conditions]]. In 1990–1991, oxygen concentrations in the mixed layer were higher than in 1960–1961, with nearly continuous oxygen supersaturation in surface waters. Oxygen concentrations in [[Hypolimnion|hypolimnetic waters]] (i.e., the layer of water that lies below the [[thermocline]], is noncirculating, and remains perpetually cold) were lower in 1990–1991 for a longer period than in 1960–1961, with values of less than 1&nbsp;mg per litre (< 0.4&nbsp;[[Grain (mass)|gr]]/cu&nbsp;ft) occurring in water as shallow as {{convert|40|m|ft}} compared with a shallowest occurrence of greater than {{convert|50|m|ft}} in 1961. The changes in oxygenation are considered consistent with measurements of higher algal biomass and productivity.<ref>{{cite journal | url=https://www.researchgate.net/publication/240845630  | author1=R.E. Hecky | author2=F.W.B. Bugenyi | author3=P. Ochumba | author4=J.F. Talling | author5=R. Mugidde | author6=M. Gophen | author7=L. Kaufman | year=1994 | title=Deoxygenation of the deep water of Lake Victoria, East Africa | journal=[[Limnology and Oceanography]] | volume=39 | issue=6  |pages=1476–81 | jstor=2838147 | doi=10.4319/lo.1994.39.6.1476| bibcode=1994LimOc..39.1476H | doi-access=free }}</ref> These changes have arisen for multiple reasons: successive burning within its basin,<ref>{{Cite journal | author=R.E. Hecky | year=1993 | title=The eutrophication of Lake Victoria | journal=[[Verhandlungen der Internationale Vereinigung für Limnologie]] | volume=25 | issue=1 | pages=39–48 | doi=10.1080/03680770.1992.11900057| bibcode=1993SILP...25...39H }}</ref> soot and ash from which has been deposited over the lake's wide area; from increased nutrient inflows via rivers,<ref name="OchumbaKibaara">{{cite journal | author1=Peter B. O. Ochumba | author2=David I. Kibaara | year=1989 | title=Observations on blue-green algal blooms in the open waters of Lake Victoria, Kenya | journal=[[African Journal of Ecology]] | volume=27 | issue=1 | pages=23–34  | doi=10.1111/j.1365-2028.1989.tb00925.x| bibcode=1989AfJEc..27...23O }}</ref> and from increased pollution associated with settlement along its shores.<ref>{{Cite news|date=March 2018|title=Environmental and Social Management Framework-ESMF|work=World Bank Document - Early Warning System|url=https://ewsdata.rightsindevelopment.org/files/documents/82/WB-P163782_3UJvON4.pdf|access-date=26 May 2020}}</ref>

Between 2010 and 2022 the surface area of Lake Victoria increased by 15%<ref>{{Cite web |last=Keriako |first=Tobiko |date=2021 |title=Rising Water Levels in Kenya's Rift Valley Lakes, Turkwel Gorge Dam and Lake Victoria |url=http://www.environment.go.ke/wp-content/uploads/2021/10/MENR_Scoping_Report_Latest-5-07-21.pdf |access-date=2022-03-16 |website=Government of Kenya and UNDP |archive-date=28 April 2022 |archive-url=https://web.archive.org/web/20220428030814/http://www.environment.go.ke/wp-content/uploads/2021/10/MENR_Scoping_Report_Latest-5-07-21.pdf }}</ref> flooding lakeside communities.<ref>{{Cite web |last=Baraka |first=Carey |date=2022-03-17 |title=A drowning world: Kenya's quiet slide underwater |url=https://www.theguardian.com/world/2022/mar/17/kenya-quiet-slide-underwater-great-rift-valley-lakes-east-africa-flooding |access-date=2022-03-17 |website=The Guardian |language=en}}</ref>

== Bathymetry ==
[[File:Lake Vic Bathy.jpg|thumb|Lake Victoria [[bathymetric]] model<ref name=":0">{{Cite journal | title=Bathymetry TIFF, Lake Victoria Bathymetry, raster, 2016 – LakeVicFish Dataverse | doi=10.7910/dvn/soeknr| date=2018-05-17 | last1=Hamilton | first1=Stuart | last2=Munyaho | first2=Anthony Taabu | last3=Krach | first3=Noah | last4=Glaser | first4=Sarah |type = Data Set|journal = Harvard Dataverse}}</ref>]]

The lake is a shallow lake considering its large geographic area with a maximum depth of approximately {{convert|80|m|ft}} and an average depth of {{convert|40|m|ft}}.<ref>{{Cite journal | author = Hamilton, S.E. | date = 2016 | title = Creation of a Bathymetric Map of Lake Victoria, Africa | journal = Salisbury.edu | location = Salisbury, MD | publisher = Salisbury University | url = http://faculty.salisbury.edu/~sehamilton/LV_Bathy/ | access-date = 26 December 2024 | archive-url = https://web.archive.org/web/20161025050539/http://faculty.salisbury.edu/~sehamilton/LV_Bathy/ | archive-date = 2016-10-25 | doi = 10.7910/DVN/SOEKNR}}</ref> A 2016 project digitized ten-thousand points and created the first true bathymetric map of the lake.<ref name=":0"/> The deepest part of the lake is offset to the east of the lake near Kenya and the lake is generally shallower in the west along the Ugandan shoreline and the south along the Tanzanian shoreline.<ref name=":0"/>

==Native wildlife==
===Mammals===
Many mammal species live in the region of Lake Victoria, and some of these are closely associated with the lake itself and the nearby wetlands. Among these are the [[hippopotamus]], [[African clawless otter]], [[spotted-necked otter]], [[marsh mongoose]], [[sitatunga]], [[bohor reedbuck]], [[defassa waterbuck]], [[cane rat]]s, and [[giant otter shrew]].<ref>{{cite book | author = Kingdon, J. | author-link = Jonathan Kingdon | year = 1997 | title = The Kingdon Guide to African Mammals | location = London, England | publisher = Academic Press | isbn = 0-12-408355-2}}{{full|date = December 2024}}</ref>{{page needed|date = December 2024}}

===Reptiles===
Lake Victoria and its wetlands has a large population of [[Nile crocodile]]s, as well as [[African helmeted turtle]]s, [[variable mud turtle]]s, and [[Williams' mud turtle]].<ref name="Spawls2002">{{cite book| author = Spawls, Stephen; Howell, Kim; Drewes, Robert C. & Ashe, James | date = 2002 | title = Field Guide to the Reptiles of East Africa: All the Reptiles of Kenya, Tanzania, Uganda, Rwanda and Burundi | edition = 1st | location = Princeton, NJ | publisher = Princeton University Press | isbn = 978-0-12-656470-9 }}{{full|date = December 2024}}</ref>{{page needed|date = December 2024}} The Williams' mud turtle is restricted to Lake Victoria and other lakes, rivers, and swamps in the upper Nile basin.<ref name="Spawls2002"/>{{page needed|date = December 2024}}

===Cichlid fish===
[[File:Pundamilia (Haplochromis) nyererei male.jpg|thumb|Unlike many other Lake Victoria cichlids, ''[[Haplochromis nyererei]]'' remains common.<ref>{{Cite iucn |last1=Witte |first1=F. |last2=de Zeeuw |first2=M.P. |last3=Brooks |first3=E. | title = ''Haplochromis nyererei'' | volume = 2016 | article-number = e.T60668A97125826 | date = 2016 | doi = 10.2305/IUCN.UK.2016-1.RLTS.T60668A97125826.en | access-date = 14 January 2018}}</ref> Compared to several other cichlids, its eyes are particularly sensitive to light, especially red, which is less affected by the decrease in water clarity caused by [[eutrophication]] than [[Color#Physics of color|short wavelength colors]]<ref name="Witte2000">{{cite journal | last1 = Witte | last2 = Msuku | last3 = Wanink | last4 = Seehausen | last5 = Katunzi | last6 = Goudswaard | last7 = Goldschmidt | year = 2000 | title = Recovery of cichlid species in Lake Victoria: an examination of factors leading to differential extinction | journal = Reviews in Fish Biology and Fisheries | volume = 10 | issue = 2| pages = 233–41 | doi = 10.1023/a:1016677515930 | bibcode = 2000RFBF...10..233W | s2cid = 39566440 | url = https://boris.unibe.ch/71524/ }}</ref>]]

Lake Victoria formerly was very rich in fish, including many endemics, but a high percentage of these became extinct since the 1940s.<ref name="Witte1992">{{cite journal | last1 = Witte | last2 = Goldschmidt | last3 = Goudswaard | last4 = Ligtvoet | last5 = van Oijen | last6 = Wanink | year = 1992 | title = Species extinction and concomitant ecological changes in Lake Victoria | journal = Netherlands Journal of Zoology | volume = 42 | issue = 2–3| pages = 214–32 | doi = 10.1163/156854291X00298 }}</ref> The main group in Lake Victoria is the [[haplochromine]] cichlids (''[[Haplochromis]]'' ''[[sensu lato]]'') with more than 500 species, almost all endemic,<ref name="Verheyen2003"/><ref name="Meier2017">{{cite journal | last1 = Meier | last2 = Marques | last3 = Mwaiko | last4 = Wagner | last5 = Excoffier | last6 = Seehausen | year = 2017 | title = Ancient hybridization fuels rapid cichlid fish adaptive radiations | journal = Nature Communications | volume = 8 | article-number = 14363 | doi = 10.1038/ncomms14363 | pmid = 28186104 | pmc = 5309898 | bibcode = 2017NatCo...814363M }}</ref><ref name="DeWeerdt2004">DeWeerdt, S. (28 February 2004). [https://www.newscientist.com/article/mg18124365-300-dark-secret-of-the-lake/ Dark secret of the lake.] New Scientist. Retrieved 26 March 2017.</ref> and including an estimated 300 that still are [[Undescribed taxon|undescribed]].<ref name="Sayer2018">Sayer, C.A., L. Máiz-Tomé, and W.R.T. Darwall (2018). Freshwater biodiversity in the Lake Victoria Basin: Guidance for species conservation, site protection, [[climate resilience]] and sustainable livelihoods. Cambridge, UK and Gland, Switzerland: IUCN.  {{doi|10.2305/IUCN.CH.2018.RA.2.en}}</ref> This is far more species of fish than any other lake in the world, except [[Lake Malawi]].<ref name="Turner2001">{{cite journal |last1=Turner |last2=Seehausen |last3=Knight |last4=Allender |last5=Robinson |year=2001 |title=How many species of cichlid fishes are there in African lakes? |journal=Molecular Ecology |volume=10 |issue= 3|pages=793–806 |doi=10.1046/j.1365-294x.2001.01200.x |pmid=11298988 |s2cid=12925712 |doi-access=free |bibcode=2001MolEc..10..793T }}</ref> These are the result of a rapid [[adaptive radiation]] in the last circa 15,000 years.<ref name="Verheyen2003"/><ref name="Meier2017"/><ref>{{cite journal | author1=J.C. Stager | author2=T.C. Johnson | year=2008 | title=The late Pleistocene desiccation of Lake Victoria and the origin of its endemic biota | journal=[[Hydrobiologia]] | volume=596 | issue=1 | pages=5–16 | doi=10.1007/s10750-007-9158-2| bibcode=2008HyBio.596....5S | s2cid=42372016 }}</ref> Their extraordinary diversity and speed of [[evolution]] have been the subjects for many scientists studying the forces that drive the richness of life everywhere.<ref name="Meier2017"/><ref name="Lowe2009">{{cite journal | last1 = Lowe-McConnell | first1 = R | year = 2009 | title = Fisheries and cichlid evolution in the African Great Lakes: progress and problems | journal = Freshwater Reviews | volume = 2 | issue = 2| pages = 131–51 | doi = 10.1608/frj-2.2.2 | s2cid = 54011001 }}</ref> The Victoria haplochromines are part of an older group of more than 700 closely related species, also including those of several smaller lakes in the region, notably [[Lake Kyoga|Kyoga]], [[Lake Edward|Edward]]–[[Lake George (Uganda)|George]], Albert, and [[Lake Kivu|Kivu]].<ref name="Verheyen2003"/><ref name="Meier2017"/>

Most of these lakes are relatively shallow (like Victoria) and part of the present-day upper Nile basin. The exception is Lake Kivu, which is part of the present-day [[Congo River basin]], but is believed to have been connected to Lakes Edward and Victoria by rivers until the uplifting of parts of the [[East African Rift]].<ref name="Verheyen2003"/> This deep lake may have functioned as an "evolutionary reservoir" for this haplochromine group in periods where other shallower lakes in the region dried out, as happened to Lake Victoria about 15,000 years ago.<ref name="Verheyen2003"/> In recent history only Lake Kyoga was easily accessible to Victoria cichlids, as further downstream movement by the [[Victoria Nile]] (to Lake Albert) is prevented by a series of waterfalls, notably [[Murchison Falls|Murchison]]. In contrast, the [[Owen Falls]] (now flooded by a [[Nalubaale Hydroelectric Power Station|dam]]) between Victoria and Kyoga were essentially a series of rapids that did not effectively block fish movements between the two lakes.<ref>McClanahan, T. and T.P. Young (1996). ''East African Ecosystems and Their Conservation''. pp. 201–06. {{ISBN|978-0-19-510817-0}}</ref>

[[File:Haplochromis thereuterion.jpg|thumb|''[[Haplochromis thereuterion]]'' survives in low numbers.<ref>{{Cite iucn |last1=Witte |first1=F. |last2=de Zeeuw |first2=M.P. |last3=Brooks |first3=E.  | title = Haplochromis thereuterion | volume = 2010 | article-number = e.T185857A8492470 | date = 2010 | doi = 10.2305/IUCN.UK.2010-3.RLTS.T185857A8492470.en | access-date = 14 January 2018}}</ref> Initially feared extinct, when rediscovered it had changed habitat (from near surface to rocky outcrops) and feeding behavior (from surface insects to insect larvae)<ref>Steeves, G: [http://www.cichlid-forum.com/articles/hap_thereuterion_pt1.php "'Haplochromis' thereuterion".] Cichlid-Forum. Retrieved 28 March 2017.</ref>]]

The Victoria haplochromines are distinctly [[sexually dimorphic]] (males relatively brightly colored; females dull),<ref>{{Cite journal | author = Rijssel | author2 = Moser | author3 = Frei | author4 = Seehausen | title = Prevalence of disruptive selection predicts extent of species differentiation in Lake Victoria cichlids | journal = Proceedings of the Royal Society B: Biological Sciences | volume = 285 | issue = 1871 | page = 1871 | date = 2018 | doi = 10.1098/rspb.2017.2630| pmid = 29367400 | pmc = 5805951 }}</ref> and their ecology is extremely diverse, falling into at least 16 groups, including [[detritivore]]s, [[Planktivore|zooplanktivores]], [[insectivore]]s, prawn-eaters, [[molluscivore]]s and [[piscivore]]s.<ref name="Lowe2009"/> As a result of predation by the introduced [[Nile perch]], [[eutrophication]] and other changes to the ecosystem, it is estimated that at least 200 species (about 40 percent) of Lake Victoria haplochromines have become extinct,<ref name="DeWeerdt2004"/><ref name="Lowe2009"/><ref name="Rijssel2013">{{cite journal |last1=van Rijssel |last2=Witte |year=2013 |title=Adaptive responses in resurgent Lake Victoria cichlids over the past 30 years |journal=Evol. Ecol. |volume=27 |issue= 2|pages=253–67 |doi=10.1007/s10682-012-9596-9 |bibcode=2013EvEco..27..253V |s2cid=2291741 }}</ref> including more than 100 undescribed species.<ref name="Sayer2018"/> Initially it was feared that this number was even higher, by some estimates 65 percent of the total species,<ref>{{cite journal |last1=Goldschmidt |last2=Witte |last3=Wanink |year=1993 |title=Cascading Effects of the Introduced Nile Perch on the Detritivorous/Phytoplanktivorous Species in the Sublittoral Areas of Lake Victoria |journal=Conservation Biology |volume=7 |issue=3 |pages=686–700 |doi=10.1046/j.1523-1739.1993.07030686.x |bibcode=1993ConBi...7..686G }}</ref> but several species that were feared extinct have been rediscovered after the Nile perch started to decline in the 1990s.<ref name="Lowe2009"/><ref name="IUCNef">IUCN Red Lists: [http://www.iucnredlist.org/initiatives/freshwater/eastafrica/geographicpatternsea Geographic Patterns]. Eastern Africa. Retrieved 25 March 2017.</ref> Several of the remaining species are seriously threatened and additional extinctions are possible.<ref name="Fiedler1998">Fiedler, P.L. and P M. Kareiva, editors (1998). Conservation Biology: For the Coming Decade. 2nd edition. pp. 209–10. {{ISBN|978-0-412-09661-7}}</ref> Some species have survived in nearby small satellite lakes,<ref name="IUCNef"/> have survived in refugias among rocks or [[papyrus sedge]]s (protecting them from the Nile perch),<ref name="Chapman1996">{{cite journal | last1 = Chapman | last2 = Chapman | last3 = Chandler | year = 1996 | title = Wetland ecotones as refugia for endangered fishes | journal = Biological Conservation | volume = 78 | issue = 3| pages = 263–70 | doi = 10.1016/s0006-3207(96)00030-4 | bibcode = 1996BCons..78..263C }}</ref> or have adapted to the human-induced changes in the lake itself.<ref name="Lowe2009"/><ref name="Rijssel2013"/> Such adaptions include a larger [[gill]] area (adaption for oxygen-poor water), changes in the feeding apparatus, changes to the eyes (giving them better sight in turbid water)<ref name="Witte2000"/><ref name="Lowe2009"/> and smaller head/larger [[caudal peduncle]] (allowing faster swimming).<ref>{{cite journal | last1 = Zeeuw | last2 = Westbroek | last3 = van Oijen | last4 = Witte | year = 2013 | title = Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania | journal = ZooKeys | issue = 256 | pages = 1–34 | doi = 10.3897/zookeys.256.3871 | pmid = 23717179| pmc = 3650828| doi-access = free | bibcode = 2013ZooK..256....1D }}</ref> The piscivorous (affected by both predation and competition from Nile perch<ref>{{cite journal | last1 = McGee | last2 = Borstein | last3 = Neches | last4 = Buescher | last5 = Seehausen | last6 = Wainwright | year = 2015 | title = A pharyngeal jaw evolutionary innovation facilitated extinction in Lake Victoria cichlids | journal = Science | volume = 350 | issue = 6264| pages = 1077–79 | doi = 10.1126/science.aab0800 | pmid = 26612951 | bibcode = 2015Sci...350.1077M | doi-access = free }}</ref>), molluscivorous and insectivorous haplochromines were particularly hard hit with many extinctions.<ref name="Lowe2009"/> Others have become extinct in their pure form, but survive as [[Hybrid (biology)|hybrids]] between close relatives (especially among the detritivores).<ref name="DeWeerdt2004"/><ref name="Lowe2009"/> The zooplanktivores have been least affected and in the late 1990s had reached densities similar to, or above, the densities before the drastic declines, although consisting of fewer species and often switching their diet towards [[macroinvertebrate]]s.<ref name="Witte2000"/><ref name="Lowe2009"/> Some of the threatened Lake Victoria cichlid species have captive "insurance" populations in zoos, [[public aquaria]] and among private aquarists, and a few species are [[extinct in the wild]] (only survive in captivity).<ref>Yirka, B. (27 November 2015). [https://phys.org/news/2015-11-evolution-diversification.html Study shows evolution does not always mean more diversification.] Phys.org, press release. Retrieved 28 March 2017.</ref><ref>Lévêque, C. (1997). ''Biodiversity Dynamics and Conservation: The Freshwater Fish of Tropical Africa''. p. 358. {{ISBN|978-0-521-57033-6}}</ref><ref>Steeves, G: [http://www.cichlid-forum.com/articles/new_hobby_haps_pt1.php "New to the hobby Haplochromines".] ''Cichlid-Forum''. Retrieved 28 March 2017.</ref><ref>Rizza, D: [http://www.wetwebmedia.com/ca/volume_6/volume_6_3/vic_chichlids.html "Looking At Victoria Cichlids".] ''Conscientious Aquarist Magazine''. Retrieved 28 March 2017.</ref><ref>McAndrews, R. and D.I. Warmolts (25 May 2015). [http://www.bostonaquariumsociety.org/index.php?option=com_content&view=article&id=89:progress-in-breeding-freshwater-fish-by-douglas-i-warmolts-columbus-zoological-gardens-and-russ&catid=42:general&Itemid=74 "Progress in breeding freshwater fish".] Boston Aquarium Society. Retrieved 14 April 2017.</ref>

Before the mass extinction that has occurred among the lake's cichlids in the last 50 years, about 90 percent of the native fish species in the lake were haplochromines.<ref name="Witte1992"/> Disregarding the haplochromines, the only native Victoria cichlids are two [[critically endangered]] tilapia, the [[Singida tilapia]] or ''[[ngege]]'' (''Oreochromis esculentus'') and [[Victoria tilapia]] (''O. variabilis'').<ref>{{Cite iucn | author = Twongo, T.K. | author2 = Bayona, J.D.R. | author3 = Hanssens, M. | name-list-style = amp | title = ''Oreochromis esculentus'' | volume = 2006 | article-number = e.T15457A4587658 | date = 2006 | doi = 10.2305/IUCN.UK.2006.RLTS.T15457A4587658.en | access-date = 14 January 2018}}</ref><ref>{{Cite iucn | author = Twongo, T.K. | author2 = Bayona, J.D.R. | author3 = Hanssens, M. | name-list-style = amp | title = ''Oreochromis variabilis'' | volume = 2006 | article-number = e.T15458A4587788 | date = 2006 | doi = 10.2305/IUCN.UK.2006.RLTS.T15458A4587788.en | access-date = 14 January 2018}}</ref>

In 1927–1928 [[Michael Graham (scientist)|Michael Graham]] conducted the first ever systematic [[Fisheries Survey of Lake Victoria]]. In his official report of the expedition, Graham wrote that "The ngege or satu ''Tilapia esculenta'', is the most important food fish of the lake, whether for native or non-native consumption. No other fish equals it in the quality of the flesh. It is convenient size for trade, travels well and is found in much greater numbers than other important fish, such as semutundu (Luganda), ''Bagrus sp.''".<ref name=":25">Graham M. (1929.) The Victoria Nyanza and Its Fisheries: A Report on the Fish Survey of Lake Victoria 1927–1928 and Appendices. London: Crown Agents for the Colonies. 256pp.</ref> Furthermore, Graham noted that the introduction of the European flax [[gill net]] of 5 inch mesh had undoubtedly caused a diminution in the number of ngege in those parts of the Kavirondo Gulf, the northern shore of the lake, the Sesse Islands and Smith's Sound which are conveniently situated close to markets.<ref name=":25"/> Survey catches in 1927–28 included several [[Haplochromis]] species that are now thought to be extinct, including: ''[[Haplochromis flavipinnis]]'', ''[[Haplochromis gowersii]]'', ''[[Haplochromis longirostris]]'', ''[[Haplochromis macrognathus]]'', ''[[Haplochromis michaeli]]'', ''[[Haplochromis nigrescens]]'', ''[[Haplochromis prognathus]]''.
[[File:The use of boats for transport on lake Victoria uganda.jpg|alt=View at Lake Victoria (Uganda).|thumb|View at Lake Victoria  in Uganda]]
[[File:Nile monitor lizard, Lake Victoria (1) (28017355603).jpg|thumb|Nile monitor lizard, Lake Victoria.]]
As well as being due to the introduction of [[Nile perch]], the extinction of cichlids in the genus ''[[Haplochromis]]'' has also been blamed on the lake's eutrophication. The fertility of tropical waters depends on the rate at which nutrients can be brought into solution. The influent rivers of Lake Victoria provide few nutrients to the lake in relation to its size. Because of this, most of Lake Victoria's nutrients are thought to be locked up in lake-bottom deposits.<ref name="Hickling61" />{{page needed|date = December 2024}}<ref name="Beauchamp54">{{cite journal|author=Beauchamp, R.S.A. |year=1954|title=Fishery research in the lakes of East Africa|journal=East African Agricultural Journal|volume=19|issue=4|pages=203–07|doi=10.1080/03670074.1954.11664909}}</ref> By itself, this vegetative matter decays slowly. Animal flesh decays considerably faster, however, so the fertility of the lake is dependent on the rate at which these nutrients can be taken up by fish and other organisms.<ref name="Beauchamp54" /> There is little doubt that ''Haplochromis'' played an important role in returning detritus and plankton back into solution.<ref name="Lucy Richardson">{{citation|author=Richardson, Lucy |title=The lessons of Lake Victoria Uganda|url=http://www.gulgasht.com/africa/lucy-richardson-story-from-lake-victoria-uganda.html|archive-url=https://web.archive.org/web/20140926071844/http://www.gulgasht.com/africa/lucy-richardson-story-from-lake-victoria-uganda.html|archive-date=2014-09-26}}</ref><ref name="KaufmanOchumba93">{{cite journal|author1=Les Kaufman|author2=Peter Ochumba|year=1993|title=Evolutionary and conservation biology of cichlid fishes as revealed by faunal remnants in northern Lake Victoria|journal=[[Conservation Biology (journal)|Conservation Biology]]|volume=7|issue=3|pages=719–30|doi=10.1046/j.1523-1739.1993.07030719.x|jstor=2386703|bibcode=1993ConBi...7..719K }}</ref><ref name="Goldschmidt93">{{cite journal|author1=Tijs Goldschmidt|author2=Frans Witte|author3=Jan Wanink|year=1993|title=Cascading effects of the introduced Nile perch on the detrivorous/phytoplantivorous species in sublittoral areas of Lake Victoria|journal=[[Conservation Biology (journal)|Conservation Biology]]|volume=7|issue=3|pages=686–700|doi=10.1046/j.1523-1739.1993.07030686.x|jstor=2386700|bibcode=1993ConBi...7..686G }}</ref> With some 80 percent of ''Haplochromis'' species feeding off detritus, and equally capable of feeding off one another, they represented a tight, internal recycling system, moving nutrients and biomass both vertically and horizontally through the water column, and even out of the lake via predation by humans and terrestrial animals. The removal of ''Haplochromis'', however, may have contributed to the increasing frequency of [[algal bloom]]s,<ref name="OchumbaKibaara" /><ref name="KaufmanOchumba93" /><ref name="Goldschmidt93" /> which may in turn be responsible for mass [[fish kill]]s.<ref name="OchumbaKibaara" />

===Other fish===
The non-cichlid native fish include African tetras (''[[Brycinus]]''), cyprinids (''[[Enteromius]]'', ''[[Garra]]'', ''[[Labeo]]'', ''[[Labeobarbus]]'', ''[[Rastrineobola]]'' and ''[[Xenobarbus]]''), airbreathing catfish (''[[Clariallabes]]'', ''[[Clarias]]'' and ''[[Xenoclarias]]''), bagrid catfish (''[[Bagrus]]''), loach catfish (''[[Amphilius]]'' and ''[[Zaireichthys]]''), [[Schilbe intermedius|silver butter catfish]] (''Schilbe intermedius''), ''[[Synodontis]]'' squeaker catfish, ''[[Nothobranchius]]'' killifish, poeciliids (''[[Aplocheilichthys]]'' and ''[[Micropanchax]]''), the spiny eel ''[[Mastacembelus]] frenatus'', elephantfish (''[[Gnathonemus]]'', ''[[Hippopotamyrus]]'', ''[[Marcusenius]]'', ''[[Mormyrus]]'', ''[[Petrocephalus]]'', and ''[[Pollimyrus]]''), the climbing gourami ''[[Ctenopoma]] muriei'' and [[marbled lungfish]] (''Protopterus aethiopicus'').<ref name="FishBaseList">FishBase: [http://www.fishbase.org/TrophicEco/FishEcoList.php?ve_code=3 Fish Species in Victoria.] Retrieved 25 March 2017.</ref>
[[File:Victoria Nyanza, voyages de MM. J. Jackson & Gedge et Père Schynse - DPLA - 56a4977fa3409e9beb528ee7ca96e923.jpg|alt=Lake Victoria|left|thumb|Map of Lake Victoria]]
At a genus level, most of these are widespread in Africa, but the very rare ''Xenobarbus'' and ''Xenoclarias'' are endemic to the lake, and the common ''Rastrineobola'' is near-endemic.<ref name="FishBaseList"/>

===Crustaceans===
Four species of [[freshwater crab]]s are known from Lake Victoria: ''[[Potamonautes niloticus]]'' is widespread in the lake and ''[[Potamonautes emini|P. emini]]'' has been recorded from the vicinity of [[Bukoba]] in Tanzania, but both are also found elsewhere in Africa.<ref>Cumberlidge, N. (2009). "Freshwater Crabs and Shrimps (Crustacea: Decapoda) of the Nile Basin". Chapter 27, pp. 547–61 in : Dumony, H.J. (editor). ''The Nile. Origin, Environments, Limnology and Human Use. Monographiae Biologicae'', Vol. 89. Springer, New York. {{ISBN|978-1-4020-9726-3}}.</ref><ref>{{Cite iucn | author = Cumberlidge, N. | title = ''Potamonautes emini'' | volume = 2016 | article-number = e.T44523A84352263 | date = 2016 | doi = 10.2305/IUCN.UK.2016-3.RLTS.T44523A84352263.en | access-date = 14 January 2018}}</ref> The last were first scientifically described in 2017 and very little is known about them: ''[[Potamonautes entebbe|P. entebbe]]'' is only known from near [[Entebbe]] (the only known specimen was collected in 1955 and it is unknown if it was in or near the lake) and ''[[Potamonautes busungwe|P. busungwe]]'' only at Busungwe Island in the northwestern part of the lake. The latter likely is the smallest African freshwater crab with a carapace width up to about {{cvt|1.6|cm|in|1}}, although ''[[Potamonautes kantsyore|P. kantsyore]]'' of [[Kagera River]], and ''[[Platythelphusa]] maculata'' and ''P. polita'' of Lake Tanganyika are almost as small.<ref>{{cite journal | last1 = Cumberlidge | first1 = N. | last2 = Clark | first2 = P.F. | year = 2017 | title = Description of three new species of Potamonautes MacLeay, 1838 from the Lake Victoria region in southern Uganda, East Africa (Brachyura: Potamoidea: Potamonautidae) | journal = European Journal of Taxonomy | issue = 371| pages = 1–19 | doi = 10.5852/ejt.2017.371 | doi-access = free | hdl = 10141/622400 | hdl-access = free }}</ref>
[[File:Lake Victoria IMG 20200202 145633.jpg|alt=Lake Victoria.|thumb|Lake Victoria from a wider angle.]]
The only shrimp/prawn is ''[[Caridina nilotica]]'',<ref>{{cite journal | last1 = Goudswaard | first1 = K. | last2 = Witte | first2 = F. | last3 = Wanink | first3 = J.H. | year = 2006 | title = The shrimp Caridina nilotica in Lake Victoria (East Africa), before and after the Nile perch increase | journal = Hydrobiologia | volume = 563 | issue = 1| pages = 31–44 | doi = 10.1007/s10750-005-1385-9 | bibcode = 2006HyBio.563...31G | s2cid = 40935454 }}</ref> which is common and widespread in Lake Victoria.<ref name="Lowe2009"/>

===Molluscs===
Lake Victoria is home to 28 species of [[freshwater snail]]s (e.g., ''[[Bellamya (gastropod)|Bellamya]]'', ''[[Biomphalaria]]'', ''[[Bulinus]]'', ''[[Cleopatra (gastropod)|Cleopatra]]'', ''[[Gabbiella]]'', and ''[[Melanoides]]''), including 12 endemic species/subspecies.<ref name="Darwall2011">{{Cite book | editor1=Darwall, W. | editor2=Smith, K. | editor3=Allen, D. | editor4=Holland, R. | editor5=Harrison, I. | editor6=Brooks, E. | year=2011 | title=The Diversity of Life in African Freshwaters: Under Water, Under Threat. An Analysis of the Status and Distribution of Freshwater Species Throughout Mainland Africa | author1=Seddon, M. | author2=Appleton, C. | author3=Van Damme, D. | author4=Graf, D. | chapter=Freshwater Molluscs of Africa: Diversity, Distribution, and Conservation | pages=92–119 | isbn=978-2-8317-1345-8 }}</ref><ref>Brown, D. (1994). ''Freshwater Snails of Africa and Their Medical Importance.'' 2nd edition. {{ISBN|0-7484-0026-5}}{{full|date = December 2024}}</ref>{{page needed|date = December 2024}} There are 17 species of [[bivalve]]s (''[[Corbicula]]'', ''[[Coelatura]]'', ''[[Sphaerium]]'', and ''[[Byssanodonta]]''), including 6 endemic species and subspecies.<ref name="Darwall2011"/><ref>{{cite journal | last1 = Mwambungu | first1 = J.A. | year = 2004 | title = The diversity of benthic molluscs of Lake Victoria and Lake Burigi | journal = Tanzania Journal of Science| volume = 30 | issue = 1| pages = 21–32 | doi = 10.4314/tjs.v30i1.18384 | doi-access = free }}</ref> It is likely that undescribed species of snails remain. Conversely, genetic studies indicate that some [[Morphology (biology)|morphologically]] distinctive populations, traditionally regarded as separate species, may only be variants of single species.<ref name="Sayer2018"/> Two of the snail genera, ''Biomphalaria'' and  ''Bulinus'',  are [[intermediate host]]s of the parasite that causes [[bilharzia]] (schistosomiasis). Human infections by this parasite are common at Lake Victoria.<ref>{{cite news |author=Senthilingam, M. |date=9 February 2016 |title=The Snails Spreading Fever Across Africa | url=https://edition.cnn.com/2016/02/09/health/snails-spread-schistosomiasis-in-africa/index.html | publisher=CNN | access-date=16 May 2018}}</ref> This may increase as a result of the spread of the invasive water hyacinth (an optimum snail habitat),<ref>{{cite web |author=Chege, N. |date=1995 |title=Lake Victoria: A Sick Giant |url=http://faculty.fgcu.edu/twimberley/EnviroPhilo/LakeVictoriaCrisis.pdf |publisher=People & the Planet |access-date=16 May 2018 |archive-date=17 May 2018 |archive-url=https://web.archive.org/web/20180517153755/http://faculty.fgcu.edu/twimberley/EnviroPhilo/LakeVictoriaCrisis.pdf }}</ref> and the loss of many snail-eating cichlids in the lake.<ref>{{cite web |author=Pomerantz, J. |date=19 September 2015 |title=Haplochromine Cichlids of Lake Victoria |url=https://www.ecologycenter.us/natural-history-2/haplochromine-cichlids-of-lake-victoria.html |publisher=ecologycenter.us |access-date=16 May 2018 |archive-date=4 August 2018 |archive-url=https://web.archive.org/web/20180804140824/https://www.ecologycenter.us/natural-history-2/haplochromine-cichlids-of-lake-victoria.html }}</ref>

===Spiders===
''[[Evarcha culicivora]]'' is a species of jumping spider (family [[Salticidae]]) found only around Lake Victoria in Kenya and Uganda. It feeds primarily on female mosquitos.<ref>{{Cite journal|last1=Nelson|first1=Ximena J.|last2=Jackson|first2=Robert R.|last3=Sune|first3=Godfrey|date=2005|title=Use of Anopheles-Specific Prey-Capture Behavior by the Small Juveniles of Evarcha culicivora, a Mosquito-Eating Jumping Spider|journal=The Journal of Arachnology|volume=33|issue=2|pages=541–548|doi=10.1636/05-3.1|issn=0161-8202|jstor=4129852|s2cid=55244513|url=https://www.biodiversitylibrary.org/part/228863}}</ref>

==Fisheries==
[[File:Ugandan fishing boats.jpg|thumb|Fishers and their boats on the shore of Lake Victoria]]
{{Main|Fishing on Lake Victoria}}
Lake Victoria supports Africa's largest inland [[fishery]] (as of 1997).<ref name="Geheb97">{{cite thesis |author=Kim Geheb |year=1997 |title=The Regulators and the regulated: fisheries management, options and dynamics in Kenya's Lake Victoria Fishery |degree=[[PhD]] |publisher=[[University of Sussex]] |url=http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.336275 |archive-date=7 October 2011 |access-date=12 October 2010 |archive-url=https://web.archive.org/web/20111007142331/http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.336275 }}</ref> Initially the fishery involved native species, especially tilapia and haplochromine cichlids, but also catfish (''Bagrus'', ''Clarias'', ''Synodontis'' and silver butter catfish), elephantfish, [[ningu]] (''Labeo victorianus'') and marbled lungfish (''Protopterus aethiopicus'').<ref name="LVFO2016">Lake Victoria Fisheries Organization (2016). {{cite web |url=http://www.lvfo.org/index.php/lvfo/lvfo-secretariat/5-lake-victoria-fisheries-an-introduction |title=Lake Victoria Fisheries: An introduction |access-date=2017-03-27 |archive-url=https://web.archive.org/web/20160915061916/http://www.lvfo.org/index.php/lvfo/lvfo-secretariat/5-lake-victoria-fisheries-an-introduction |archive-date=15 September 2016 }}</ref><ref name="Njiru2005">{{cite journal | last1 = Njiru | last2 = Waithaka | last3 = Muchiri | last4 = van Knaap | last5 = Cowx | year = 2005 | title = Exotic introductions to the fishery of Lake Victoria: What are the management options? | journal = Lakes & Reservoirs: Research and Management | volume = 10 | issue = 3 | pages = 147–55 | doi = 10.1111/j.1440-1770.2005.00270.x | bibcode = 2005LRRM...10..147N | url = http://karuspace.karu.ac.ke/handle/20.500.12092/2060 | archive-date = 2 February 2021 | access-date = 20 December 2020 | archive-url = https://web.archive.org/web/20210202102022/https://karuspace.karu.ac.ke/handle/20.500.12092/2060 }}</ref> Some of these, including tilapia and ningu (''Labeo victorianus''), had already declined in the first half of the 20th century due to [[overfishing]].<ref name="Lowe2009"/><ref>{{Cite iucn | author = FishBase team RMCA & Geelhand, D. | title = ''Labeo victorianus'' | volume = 2016 | article-number = e.T60318A47182908 | date = 2016 | doi = 10.2305/IUCN.UK.2016-3.RLTS.T60318A47182908.en | access-date = 14 January 2018}}</ref> To boost fishing, several species of non-native tilapia and Nile perch were introduced to the lake in the 1950s. Nevertheless, the natives continued to dominate fisheries until the 1970s where their decline meant that there was a strong shift towards the non-native [[Nile tilapia]] (now 7 percent of catches), non-native Nile perch (60 percent) and the native [[Lake Victoria sardine]] (30 percent).<ref name="Lowe2009"/><ref name="Njiru2005"/> Because of its small size, the abundant open-water Lake Victoria sardine only supported minor fisheries until the decline of other natives.<ref name="Njiru2005"/> At the peak in the early 1990s, {{convert|500000|t}} of Nile perch were landed annually in Lake Victoria, but this has declined significantly in later years.<ref name="Lowe2009"/>

==Environmental issues==
A number of [[environmental issue]]s are associated with Lake Victoria and the complete disappearance of many endemic cichlid species has been called the "most dramatic example of human-caused extinctions within an ecosystem".<ref name="Fiedler1998"/>

===Invasive fish===
Starting in the 1950s, many species have been [[Introduced species|introduced]] to Lake Victoria where they have become [[Invasive species|invasive]] and a prime reason for the extinction of many [[endemic]] [[haplochromine]] cichlids.<ref name="Witte1992"/> Among the introductions are several [[tilapia]]s: [[Redbreast tilapia|redbreast]] (''Coptodon rendalli''), [[Redbelly tilapia|redbelly]] (''C. zillii''),  Nile (''Oreochromis niloticus'') and [[Oreochromis leucostictus|blue-spotted tilapias]] (''O. leucostictus'').<ref name="Lowe2009"/><ref name="Njiru2005"/><ref name="Pringle2005">Pringle, R.M. (2005). [https://academic.oup.com/bioscience/article/55/9/780/286121/The-Origins-of-the-Nile-Perch-in-Lake-Victoria The Origins of the Nile Perch in Lake Victoria.] BioScience 55 (9): 780–787.</ref> Although these have contributed to the extinction of native fish by causing significant changes to the [[ecosystem]], outcompeted natives and (in the case of the Nile tilapia) possibly hybridized with the highly threatened native tilapias, the most infamous introduction was the large and highly predatory [[Nile perch]] (''Lates niloticus'').<ref name="Witte1992"/><ref name="Lowe2009"/><ref name="Njiru2005"/>

[[File:Lates niloticus 2.jpg|thumb|upright|The [[Nile perch]] was introduced to Lake Victoria for fishing, and can reach up to {{convert|2|m|ft|abbr=on}} and {{convert|200|kg|lb|abbr=on}}.<ref>{{FishBase | genus = Lates | species = niloticus  | month = March| year = 2017}}</ref>]]
As early as the 1920s, it was proposed to introduce a large pelagic predator such as the Nile perch to improve the fisheries in the lake. At the same time it was warned that this could present a serious danger to the native fish species and required extensive research into possible ecological effects before done.<ref name="Pringle2005"/> These warnings primarily concerned the native tilapia ''O. esculentus'', as the smaller haplochromine cichlids (despite playing an important role in local fisheries) were regarded as "trash fish" by the colonial government.<ref name="Pringle2005"/> In the following decades, the pressure to introduce the Nile perch continued, as did warnings about the possible effects of doing it.<ref name="Pringle2005"/> The first introduction of Nile perch to the region, done by the [[Uganda Game and Fisheries Department]] (then part of the colonial government) and local African fish guards, happened upstream of Murchison Falls directly after the completion of the Owen Falls Dam in 1954. This allowed it to spread to Lake Kyoga where additional Nile perch were released in 1955, but not Victoria itself.<ref name="Pringle2005"/> Scientists argued that further introduction should wait until research showed the effect of the introduction in Kyoga, but by the late 1950s, Nile perch began being caught in Lake Victoria.<ref name="Pringle2005"/> As the species was already present, there were few objections when more Nile perch were transferred to Victoria to further bolster the stock in 1962–63.<ref name="Pringle2005"/> 

The origin of the first Victoria introductions in the 1950s is not entirely clear and indisputable evidence is lacking. Uganda Game and Fisheries Department (UGFD) officials denied that they were involved, but circumstantial evidence suggests otherwise and local Africans employed by UGFD have said that they introduced the species in 1954–55 under the directive of senior officials.<ref name="Pringle2005"/> UGFD officials argued that Nile perch must have spread to Lake Victoria by themselves by passing through the Owen Falls Dam when shut down for maintenance, but this is considered highly unlikely by many scientists.<ref name="Pringle2005"/> The Nile perch had spread throughout the lake by 1970.<ref name="Lowe2009"/> Initially the population of the Nile perch was relatively low, but a drastic increase happened, peaking in the 1980s, followed by a decline starting in the 1990s.<ref name="Lowe2009"/>

===Water hyacinth invasion===
{{Main|Water hyacinth in Lake Victoria}}
[[File:NdereIsland3.jpg|right|thumb|A [[Water hyacinth|hyacinth]]-choked lakeshore at [[Ndere Island]], Lake Victoria, [[Kenya]].]]
The [[water hyacinth]] has become a major [[invasive plant species]] in Lake Victoria.

The release of large amounts of untreated wastewater (sewage) and agricultural and industrial runoff directly into Lake Victoria over the past 30 years has greatly increased the nutrient levels of nitrogen and phosphorus in the lake "triggering massive growth of exotic water hyacinth, which colonised the lake in the late 1990s".<ref name="Luilo">Luilo, G.B. (August 01, 2008). Lake Victoria water resources management challenges and prospects: a need for equitable and sustainable institutional and regulatory frameworks ''African Journal of Aquatic Science'' 33, 2, 105–13.</ref><ref>{{cite journal | last1 = Muli | first1 = J. | last2 = Mavutu | first2 = K. | last3 = Ntiba | first3 = J. | year = 2000 | title = Micro-invertebrate fauna of water hyacinth in Kenyan waters of Lake Victoria | journal = International Journal of Ecology and Environmental Science | volume = 20 | pages = 281–302 }}</ref> This invasive weed creates anoxic (total depletion of oxygen levels) conditions in the lake, inhibiting decomposing plant material, raising toxicity and disease levels to both fish and people. At the same time, the plant's mat or "web" creates a barrier for boats and ferries to maneuver, impedes access to the shoreline, interferes with hydroelectric power generation, and blocks the intake of water for industries.<ref name="Luilo"/><ref name="Kateregga, E. & Sterner, T.">Kateregga, E., & Sterner, T. (January 01, 2009). "Lake Victoria Fish Stocks and the Effects of Water Hyacinth". ''Journal of Environment & Development'', 18, 1, 62–78.</ref><ref>Mailu, A.M., G.R.S. Ochiel, W. Gitonga and S.W. Njoka. 1998. ''Water Hyacinth: An Environmental Disaster in the Winam Gulf of Lake Victoria and its Control'', pp. 101–05.</ref><ref>{{cite journal | last1 = Gichuki | first1 = J. | last2 = Guebas | first2 = F. Dahdouh | last3 = Mugo | first3 = J. | last4 = Rabour | first4 = C.O. | last5 = Triest | first5 = L. | last6 = Dehairs | first6 = F. | year = 2001 | title = Species inventory and the local uses of the plants and fishes of the Lower Sondu Miriu wetland of Lake Victoria, Kenya | journal = Hydrobiologia | volume = 458 | issue = 1–3 | pages = 99–106 | doi = 10.1023/A:1013192330498 | bibcode = 2001HyBio.458...99G | s2cid = 34576879 }}</ref><ref name="Albright2004">Albright, T.P., Moorhouse, T.G., & McNabb, T.J. (January 1, 2004). "The Rise and Fall of Water Hyacinth in Lake Victoria and the Kagera River Basin, 1989-2001". ''Journal of Aquatic Plant Management'', 42, 73–84.</ref> On the other hand, water hyacinth mats can potentially have a positive effect on fish life in that they create a barrier to overfishing and allow for fish growth, there has even been the reappearance of some fish species thought to have been extinct in recent years. The overall effects of the water hyacinth, however, are still unknown.<ref name="Kateregga, E. & Sterner, T."/><ref>Jäger, J., Bohunovsky, L., Radosh, L., & Sustainability Project. (2008). ''Our planet: How much more can earth take?''. London: Haus.</ref>

Growth of the water hyacinth in Lake Victoria has been tracked since 1993, reaching its maxima biomass in 1997 and then declining again by the end of 2001.<ref name="Kateregga, E. & Sterner, T."/> Greater growth was observed in the northern part of the lake, in relatively protected areas, which may be linked to current and weather patterns and could also be due to the climate and water conditions, which are more suitable to the plants growth (as there are large urban areas to the north end of the lake, in Uganda).<ref name="Albright2004"/> The invasive weed was first attempted to be controlled by hand, removed manually from the lake; however, re-growth occurred quickly. Public awareness exercises were also conducted.<ref name="Albright2004"/> More recently, measures have been used such as the introduction of natural insect predators, including two different water hyacinth weevils and large harvesting and chopping boats, which seem to be much more effective in eliminating the water hyacinth.<ref name="Albright2004"/><ref>Ochiel, G.S., A.M. Mailu, W. Gitonga and S.W. Njoka. 1999. ''Biological Control of Water Hyacinth on Lake Victoria, Kenya'', pp. 115–18.</ref><ref>Mallya, G.A. 1999. ''Water hyacinth control in Tanzania'', pp. 25–29.</ref><ref>United Nations Environment Programme & Belgium. (2006). ''Africa's lakes: Atlas of our changing environment''. Nairobi, Kenya: UNEP.</ref> A green power plant that uses harvested water hyacinth (but also can use other degradable waste) was constructed in [[Kisumu County]] in 2013. In addition to the [[biogas]] it produces, its by-product can be used as [[fertilizer]].<ref name="Sayer2018"/>

Other factors which may have contributed to the decline of the water hyacinth in Lake Victoria include varying weather patterns, such as El Niño during the last few months of 1997 and first six months of 1998 bringing with it higher levels of water in the lake and thus dislodging the plants. Heavy winds and rains along with their subsequent waves may have also damaged the plants during this same time frame. The plants may not have been destroyed, instead merely moved to another location. Additionally, the water quality, nutrient supply, temperature, and other environmental factors could have played a role. Overall, the timing of the decline could be linked to all of these factors and perhaps together, in combination, they were more effective than any one deterrent would have been by itself.<ref name="Albright2004"/> The water hyacinth is in remission and this trend could be permanent if control efforts are continued.<ref>Crisman, T.L., Chapman, Lauren J., Chapman, Colin A., & Kaufman, Les S. (2003). ''Conservation, ecology, and management of African fresh waters''. Gainesville: University Press of Florida.</ref>

=== Pollution ===
[[File:Density evolution Victoria.png|thumb|upright=1.25|Population density around Lake Victoria]]
Pollution of Lake Victoria is mainly due to discharge of [[raw sewage]] into the lake, dumping of domestic and industrial waste, and fertiliser and chemicals from farms.

The Lake Victoria basin, while generally rural, has many major centres of population. Its shores are dotted with key cities and towns, including [[Kisumu]], [[Kisii, Kenya|Kisii]], and [[Homa Bay]] in Kenya; [[Kampala]], [[Jinja, Uganda|Jinja]] and Entebbe in Uganda; and Bukoba, [[Mwanza]], and [[Musoma]] in Tanzania. These cities and towns are also home to many factories that discharge some chemicals directly into the lake or its influent rivers. The set up of small beaches and local authorities around the lake lack proper sewage treatment facilities allowing pollutants to find their way into the water.<ref>{{Cite web|url=https://www.nation.co.ke/nationprime/poisons-lake-victoria-kenya/5279428-5458326-xlnisn/index.html|title=Toxic dump: The poisons killing lake Victoria|website=Daily Nation|language=en|access-date=2020-02-18}}</ref><ref>{{Cite journal|last1=Nantaba|first1=Florence|last2=Wasswa|first2=John|last3=Kylin|first3=Henrik|last4=Palm|first4=Wolf-Ulrich|last5=Bouwman|first5=Hindrik|last6=Kümmerer|first6=Klaus|date=January 2020|title=Occurrence, distribution, and ecotoxicological risk assessment of selected pharmaceutical compounds in water from Lake Victoria, Uganda|journal=Chemosphere|volume=239|article-number=124642|doi=10.1016/j.chemosphere.2019.124642|pmid=31521936|bibcode=2020Chmsp.23924642N|s2cid=202581465|issn=0045-6535|url=http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-161909}}</ref>  Large parts of these urban areas also discharge untreated (raw) sewage into the river, increasing its [[eutrophication]] that in turn is helping to increase the invasive water hyacinth.<ref name="earthobservatory.nasa.gov">{{cite news |url=http://earthobservatory.nasa.gov/IOTD/view.php?id=7426 |title=Water Hyacinth Re-invades Lake Victoria |publisher=[[NASA]] |date=February 21, 2007 |work=Image of the Dat}}</ref> Increased [[logging]] and act of [[deforestation]] has led to [[environmental degradation]] around the region reducing the absorption of polluting chemicals and deteriorating the water quality.<ref>{{Cite web|url=https://www.standardmedia.co.ke/article/2001249889/scientists-raise-concerns-over-pollution-of-lake-victoria|title=Scientists raise concerns over pollution of Lake Victoria|last=Odhiambo|first=Harold|website=The Standard|language=en|access-date=2020-02-18}}</ref>

=== Environmental data ===
As of 2016, an environmental data repository exists for Lake Victoria.<ref>{{Cite web|title=LakeVicFish Dataverse|url=https://dataverse.harvard.edu/dataverse/LakeVicFish|website=dataverse.harvard.edu|language=en|access-date=2020-05-27}}</ref> The repository contains shoreline, bathymetry, pollution, temperature, wind vector, and other important data for both the lake and the wider Basin.

== History and exploration ==
[[File:The National Archives UK - CO 1069-3-183.jpg|thumb|Bismarck Rock]]
The first recorded information about Lake Victoria comes from [[Arab]] traders plying the inland routes in search of [[gold]], [[ivory]], other precious commodities, and [[slave]]s.

[[File:Africa Lake Victoria 10 006.jpg|left|thumb|The lake as seen from the shores of the Speke Resort in Kampala, Uganda]]

Many Africans tribes lived in the catchment area around the lake. It was first sighted by a [[European ethnic groups|European]] in 1858 when the [[British people|British]] explorer [[John Hanning Speke]] reached its southern shore while on his journey with [[Richard Francis Burton]] to explore central Africa and locate the Great Lakes. Believing he had found the source of the Nile on seeing this "vast expanse of open water" for the first time, Speke named the lake after Queen Victoria. Burton, who had been recovering from illness at the time and resting further south in Kazeh (near present-day [[Tabora]]),<ref>{{Cite book |last=Millard |first=Candice |title=River of the Gods |publisher=Knopf Doubleday Publishing Group}}{{full|date = December 2024}}</ref>{{page needed|date = December 2024}} was outraged that Speke claimed to have proved his discovery to have been the true source of the Nile River, which Burton regarded as still unsettled. A very public quarrel ensued, which not only sparked a great deal of intense debate within the scientific community of the day, but also much interest by other [[List of explorers|explorers]] keen to either confirm or refute Speke's discovery.<ref name = "DNB">{{DNB Cite|wstitle=Speke, John Hanning}}</ref>
[[File:View at Lake Victoria (Uganda).jpg|thumb|Motorboat on Lake Victoria, near the Ugandan shore]]
In the late 1860s, the famous Scottish [[explorer]] and [[missionary]] [[David Livingstone]] failed in his attempt to verify Speke's discovery, instead pushing too far west and entering the [[River Congo]] system instead.<ref>{{cite web| url=http://www.jambokenya.com/jambo/location/victoria.htm| archive-url=https://archive.today/19970617231906/http://www.jambokenya.com/jambo/location/victoria.htm| archive-date=17 June 1997| title=Kenya, Africa – Lake Victoria in Kenya| publisher=Jambo Kenya Network| access-date=14 July 2008}}</ref> Ultimately, the British-American explorer [[Henry Morton Stanley]], on an expedition funded by the ''[[New York Herald]]'' newspaper, confirmed the truth of Speke's discovery, circumnavigating the lake and reporting the great outflow at [[Ripon Falls]] on the lake's northern shore.

== Water use ==
Many towns and cities are reliant on Lake Victoria for their water supplies, for farming and other uses.<ref>{{Cite web|title=Lake Victoria {{!}} Size, Map, Countries, & Facts|url=https://www.britannica.com/place/Lake-Victoria|access-date=2020-08-24|website=Encyclopedia Britannica|language=en}}</ref>

=== Lamadi water scheme ===
The Lamadi water scheme is a water and sanitation project that serves Mwanza and the satellite towns of Lamadi, Misungwi, Magu, Bukoba, and Musoma on the bank of Lake Victoria.  European Investment Bank started the project in 2013 with the aim of protecting the environmental health of the lake, through improved water and sanitation to the towns whose pollution is part of the degradation of the lake. The project aims to provide safe drinking water for an estimated one million people and improved sanitation for 100 000 people. Sediment and suspended solids are filtered out using sand, which acts like a sieve. The water is then ready to be chlorinated or treated in another way. The sand filtration helps reduce water-borne diseases and is based on the use of the local environment.<ref>{{Cite web|title=Development Solutions: Creative flow|url=https://www.eib.org/en/essays/creative-development-solutions|access-date=2020-08-24|website=European Investment Bank|language=en}}</ref>

===Nalubaale Dam===
{{Main|Nalubaale Power Station}}
[[File:From top of Nalubaale Power Station.jpg|thumb|right|The [[Nalubaale Hydroelectric Power Station]] in [[Njeru]], Uganda.]]
The only outflow for Lake Victoria is at Jinja, Uganda, where it forms the Victoria Nile. The water for at least 12,000 years has drained across a natural rock weir. In 1952, engineers acting for the government of [[British Uganda|Colonial Uganda]] blasted out the weir and reservoir to replace it with an artificial barrage to control the level of the lake and reduce the gradual erosion of the rock weir. A standard for mimicking the old rate of outflow called the "agreed curve" was established, setting the maximum flow rate at 300 to 1,700 [[Cubic metre per second|cubic metres per second]] (392–2,224 [[cubic yard|cu&nbsp;yd]]/sec) depending on the lake's water level.

In 2002, Uganda completed a second [[hydroelectric]] complex in the area, the [[Kiira Hydroelectric Power Station]], with [[World Bank]] assistance. By 2006, the water levels in Lake Victoria had reached an 80-year low, and Daniel Kull, an independent hydrologist living in [[Nairobi]], Kenya, calculated that Uganda was releasing about twice as much water as is allowed under the agreement,<ref>{{cite journal |url=https://www.newscientist.com/article.ns?id=mg18925384.100 |title=Uganda pulls plug on Lake Victoria |journal=[[New Scientist]] |date=9 February 2006 |author=Fred Pearce |volume=2538 |page=12 |access-date=2 September 2017 |archive-date=13 October 2008 |archive-url=https://web.archive.org/web/20081013113221/http://www.newscientist.com/article.ns?id=mg18925384.100 }}</ref> and was primarily responsible for recent drops in the lake's level.

==Transport==
[[File:Ukerewe-Mwanza Ferry.jpg|thumb|Ukerewe-Mwanza Ferry.]]<!--[[File:Lake Victoria SPOT 1128.jpg|thumb|right|Baumann Gulf in the Tanzanian portion of Lake Victoria]]-->
{{main|Lake Victoria ferries}}

Since the 1900s, [[Lake Victoria ferries]] have been an important means of transport between Uganda, Tanzania, and Kenya. The main ports on the lake are Kisumu, Mwanza, Bukoba, [[Entebbe]], [[Port Bell]], and Jinja. Until 1963, the fastest and newest ferry, [[MV Victoria (1959)|MV ''Victoria'']], was designated a [[Royal Mail Ship]]. In 1966, [[train ferry]] services between Kenya and Tanzania were established with the introduction of {{MV|Uhuru}} and {{MV|Umoja}}. The ferry [[MV Bukoba|MV ''Bukoba'']] sank in the lake on 21 May 1996 with a loss of between 800 and 1,000 lives, making it one of Africa's worst maritime disasters.<ref>{{cite news|url=https://newspaperarchive.com/panama-city-news-herald-sep-29-2002-p-8/|title=Diver's recover 180 bodies from Africa's worst ferry disaster|date=29 September 2002|work=Panama City News Herald|location=Panama city, Florida|page=8|url-access=subscription |via=Newspaperarchive.com|quote=The tragedy was one of Africa's deadliest maritime disasters. On May 21st 1996, at least 500 people died in the sinking of the MV Bukova on Lake Victoria.|last=Harris|first=Edward|access-date=6 April 2018}}</ref> Another tragedy occurred recently on 20 September 2018 that involved the passagers ferry [[Sinking of MV Nyerere|MV Nyerere]] from [[Tanzania]] that caused the deaths of over 200 people.<ref>{{Cite web|url=https://www.theeastafrican.co.ke/news/ea/Tanzania-ferry-tragedy-Mv-Nyerere-lake-victoria/4552908-4770298-j9es0f/index.html|title=Ferry tragedy: More than 200 feared dead in Tanzania|website=The East African|language=en|access-date=2020-02-18}}</ref>

On 6 November 2022, Lake Victoria was the site of a commercial passenger aircraft crash. [[Precision Air Flight 494]], an [[ATR 42|ATR 42–500]] carrying 39 passengers and four crew, crashed while approaching [[Bukoba Airport]], resulting in 19 fatalities.<ref>{{cite news|url=https://www.cnn.com/2022/11/06/africa/tanzania-plane-crash-intl |title=19 dead after commercial aircraft crashes into Lake Victoria in Tanzania |date=6 November 2022| first1=Idris |last1=Mukhtar |first2=Lauren |last2=Said-Moorhouse |first3=Larry |last3=Madowo |work=[[CNN]] |access-date=6 November 2022}}</ref><ref>{{cite news|url=https://www.reuters.com/world/africa/precision-air-plane-crashes-into-lake-victoria-tanzania-state-media-2022-11-06/|title=Passenger plane crashes into Lake Victoria in Tanzania, 19 dead| first=Nuzulack |last=Dausen |date=6 November 2022| work=[[Reuters]] |access-date=6 November 2022}}</ref>

==See also==
{{Portal|Lakes|Africa|Geography|Kenya}}
* ''[[Darwin's Nightmare]]''
* [[Kishanda]]

{{Clear}}

== References ==
{{Reflist}}

== External links ==
{{Commons category|Lake Victoria}}
{{EB1911 Poster|Victoria Nyanza|Lake Victoria}}
* [http://www.ugpulse.com/articles/daily/homepage.asp?ID=306 Decreasing levels of Lake Victoria Worry East African Countries]
* [https://www.newscientist.com/article.ns?id=mg18925384.100 New Scientist article] {{Webarchive|url=https://web.archive.org/web/20081013113221/http://www.newscientist.com/article.ns?id=mg18925384.100 |date=13 October 2008 }} on Uganda's violation of the agreed curve for hydroelectric water flow.
* [http://internationalrivers.org/en/node/1056 Dams Draining Lake Victoria] {{Webarchive|url=https://web.archive.org/web/20120310044431/http://internationalrivers.org/en/node/1056 |date=10 March 2012 }}
* [https://archive.org/details/naturalistonlake00carp ''A Naturalist on Lake Victoria, with an Account of Sleeping Sickness and the Tse-tse Fly''] (1920). T.F. Unwin Ltd, London; Biodiversity Archive
* [https://www.youtube.com/watch?v=v9VJ6cezlnU Video of Lake Victoria]
* Institutions of the East African Community: [https://web.archive.org/web/20120213132137/http://www.lvfo.org/ Lake Victoria Fisheries Organisation]

{{African Great Lakes}}
{{Lakes of Tanzania}}
{{Lakes of Kenya}}
{{Hydrography of Uganda}}

{{Authority control}}

{{DEFAULTSORT:Victoria}}
[[Category:Lake Victoria| ]]
[[Category:African Great Lakes]]
[[Category:Lakes of Kenya]]
[[Category:Lakes of Tanzania]]
[[Category:Lakes of Uganda]]
[[Category:Geography of Kampala]]
[[Category:Nile]]
[[Category:Kenya–Uganda border]]
[[Category:Kenya–Tanzania border]]
[[Category:Tanzania–Uganda border]]
[[Category:International lakes of Africa]]
[[Category:Border tripoints]]
[[Category:Geography of Kagera Region]]
[[Category:Geography of Mwanza Region]]
[[Category:Geography of Mara Region]]
[[Category:Kisumu County]]
[[Category:Homa Bay County]]