{{Short description|Lake in Uganda}} {{Infobox body of water | name = Lake Bisina | image = Kyoga Lake Complex OSM.jpg | alt = | caption = Kyoga Lake Complex with the Bisina (right) | image_bathymetry = | alt_bathymetry = | caption_bathymetry = | pushpin_map = Uganda | location = | coords = {{coord|1|36|28|N|33|57|43|E|region:UG_type:waterbody|display=inline,title}} | type = | inflow = Apedura River floodplain and seasonal streams from the surrounding catchment<ref name="NU2009intro">{{cite report |last=Odull |first=Michael Opige |last2=Byaruhanga |first2=Achilles |title=Ecological Baseline Surveys of Lake Bisina, Lake Opeta, Lake Mburo and Nakivali Wetlands Systems |publisher=NatureUganda (The East Africa Natural History Society) |year=2009 |url=https://nru.uncst.go.ug/bitstreams/ee4e416b-eb8d-4ae3-bf41-981de1adeae7/download |access-date=2025-12-18}}</ref> | outflow = Drains westwards toward Lake Kyoga through swampy margins and channels<ref name="NU2009birds">{{cite report |last=Odull |first=Michael Opige |last2=Byaruhanga |first2=Achilles |title=Ecological Baseline Surveys of Lake Bisina, Lake Opeta, Lake Mburo and Nakivali Wetlands Systems |publisher=NatureUganda (The East Africa Natural History Society) |year=2009 |url=https://nru.uncst.go.ug/bitstreams/ee4e416b-eb8d-4ae3-bf41-981de1adeae7/download |access-date=2025-12-18 |pages=44–45}}</ref> | catchment = | basin_countries = Uganda | agency = | date-built = <!-- {{Start date|YYYY|MM|DD}} For man-made and other recent lakes --> | date-flooded = <!-- {{Start date|YYYY|MM|DD}} For man-made and other recent lakes --> | length = {{convert|32|km|mi}}<ref name="NU2009plants">{{cite report |last=Odull |first=Michael Opige |last2=Byaruhanga |first2=Achilles |title=Ecological Baseline Surveys of Lake Bisina, Lake Opeta, Lake Mburo and Nakivali Wetlands Systems |publisher=NatureUganda (The East Africa Natural History Society) |year=2009 |url=https://nru.uncst.go.ug/bitstreams/ee4e416b-eb8d-4ae3-bf41-981de1adeae7/download |access-date=2025-12-18 |page=68}}</ref> | width = {{convert|6|km|mi}}<ref name="NU2009plants" /> | area = | depth = | max-depth = {{convert|5.0|m}} (recorded at sampling locations, 2008–2009)<ref name="Gidudu2011">{{cite journal |last=Gidudu |first=Brian |last2=Copeland |first2=R. S. |last3=Wanda |first3=F. |last4=Ochaya |first4=H. |last5=Cuda |first5=J. P. |last6=Overholt |first6=W. A. |title=Distribution, interspecific associations and abundance of aquatic plants in Lake Bisina, Uganda |journal=Journal of Aquatic Plant Management |volume=49 |year=2011 |pages=19–27 |url=https://apms.org/wp-content/uploads/japm-49-01-009.pdf |access-date=2025-12-18}}</ref> | volume = | residence_time = | shore = | elevation = {{convert|1,050|m}} a.s.l.<ref name="NU2009birds" /> | frozen = | islands = | cities = Mbale | reference = | extra = {{Designation list | embed = yes | designation1 = Ramsar | designation1_offname = Lake Bisina Wetland System | designation1_date = 15 September 2006 | designation1_number = 1633<ref>{{Cite web|title=Lake Bisina Wetland System|website=Ramsar Sites Information Service|url=https://rsis.ramsar.org/ris/1633|access-date=25 April 2018}}</ref>}} | other_name = Lake Salisbury, Lake Bisinia }} '''Lake Bisina''', also known as '''Lake Salisbury''' and '''Lake Bisinia''', is a freshwater lake in eastern Uganda. It is a satellite lake of Lake Kyoga, which it drains into, and the two are to some extent directly connected by papyrus swamps.<ref name=Green2009>{{cite book| author=Green, J. | year=2009 | chapter=The Kyoga Catchment | pages=205–214 | editor=H.J. Dumont | title=The Nile | series=Monographiae Biologicae | volume=89 | publisher=Springer Science + Business Media B.V | isbn=978-1-4020-9725-6 }}</ref> During the high-water rainy season, Lake Bisina can be up to {{cvt|6|m}} deep and often directly connects with the smaller Lake Opeta, but during the dry season the two are clearly separated.<ref name=Mbabazi2009>{{cite book | author= Mbabazi, D. | year=2009 | chapter=Rapid assessment of the fish biodiversity of the Mburo-Nakivali wetland systems and Opeta-Bisina wetland systems, Uganda | pages=75–84 | editor1=M.O. Opige | editor2=A. Byaruhanga | title=Ecological baseline surveys of Lake Bisina, Lake Opeta, Lake Mburo and Nakivali wetlands systems | publisher=Kampala, Uganda, Nature Uganda }}</ref>
==Conservation and ecology== Lake Bisina is one of Uganda's 33 Important Bird Areas and since 2006 a Ramsar-listed wetland of international importance.<ref name="Ramsar 12">{{cite web|last=Ramsar Convention on Wetlands |title=The Annotated Ramsar List: Uganda |url=http://www.ramsar.org/cda/en/ramsar-pubs-notes-annotated-ramsar-15873/main/ramsar/1-30-168%5E15873_4000_0__ |accessdate=28 June 2012 |url-status=dead |archiveurl=https://web.archive.org/web/20130107023855/http://www.ramsar.org/cda/en/ramsar-pubs-notes-annotated-ramsar-15873/main/ramsar/1-30-168%5E15873_4000_0__ |archivedate= 7 January 2013 }}</ref>
The lake is important for fish, notably several threatened haplochromine cichlids like ''Haplochromis orthostoma'',<ref>{{FishBase| genus=Haplochromis | species=orthostoma | month=September | year=2019 }}</ref> ''H. argenteus'' (appears to have disappeared from its main range in Lake Victoria), ''H. latifasciatus'', ''H. lividus'', ''H. martini'' (appears to have disappeared from its main range in Lake Victoria), ''H. maxillaris'', ''H. nubilus'', ''H. parvidens'', ''H. phytophagus'' and a number of undescribed species.<ref name=Wanda2011>{{cite journal | author1=Wanda, F. | author2=B. Gidudu | author3=S. Wandera | author4=R.S. Copeland | author5=J.P. Cuda | author6=W.A. Overholt | year=2011 | title=Herbivory of Hydrilla verticillata by Cichlid Fish in Lake Bisina, Uganda | journal=Journal of East African Natural History | volume=100 | issue=1&2 | pages=113–121 }}</ref> Although Nile perch was introduced to Lake Bisina in the early 1970s, recent surveys have not detected this species, which has been implicated in the extinctions of many haplochromine cichlids elsewhere.<ref name=Mbabazi2009/> A few tilapia species have also been introduced to Lake Bisina and they are still present, along with the native Singida and Victoria tilapias.<ref name=Mbabazi2009/><ref name=Wanda2011/> Other, more widespread fish species found in Lake Bisina include marbled lungfish, and various species of catfish, African tetras and elephantfish.<ref name=Mbabazi2009/> alt=Lake Bisinia along Soroti Mbale Highway,|thumb|'''Lake Bisinia along Soroti Mbale Highway'''
Surveys of Lake Bisina’s aquatic plants recorded 15 vascular aquatic plant species plus ''Chara'' spp. (a multicellular green algae).<ref name="Gidudu2011" /> The same study mapped aquatic plant patterns across the lake and reported plant communities associated with depth and water clarity gradients.<ref name="Gidudu2011" />
Lake Bisina’s wetlands support specialist wetland birds. NatureUganda surveys note breeding activity and the conservation importance of papyrus and seasonally flooded wetland habitats in the Bisina catchment.<ref name="NU2009intro" /> A targeted survey report records the Fox’s Weaver (''Ploceus spekeoides'') as a highly range-restricted species linked to seasonally flooded wetlands in north-eastern Uganda, including Lake Bisina’s catchment and fringes.<ref name="FoxWeaver2019">{{cite report |title=Fox’s Weaver Survey Report (2019) |publisher=NatureUganda |year=2019 |url=https://natureuganda.org/wp-content/uploads/2023/06/Foxs-Weaver-Survey-Report-2019.pdf |access-date=2025-12-18 |page=2}}</ref>
NatureUganda baseline reporting highlights pressures from cultivation, grazing, wetland conversion and sedimentation as key risks to wetland functions and biodiversity in the Bisina–Opeta wetland system.<ref name="NU2009plants" /> Species-focused field reports also point to habitat loss and modification in seasonally flooded wetlands as a core threat for restricted-range wetland birds recorded in the wider Lake Bisina catchment.<ref name="FoxWeaver2019" />
== Geography and hydrology == Lake Bisina lies about 15 km north of Kumi town and about 20 km east of Soroti.<ref name="NU2009birds" /> The lake covers about 192 km2 and sits around 1,050 m above sea level.<ref name="NU2009site">{{cite report |last=Odull |first=Michael Opige |last2=Byaruhanga |first2=Achilles |title=Ecological Baseline Surveys of Lake Bisina, Lake Opeta, Lake Mburo and Nakivali Wetlands Systems |publisher=NatureUganda (The East Africa Natural History Society) |year=2009 |url=https://nru.uncst.go.ug/bitstreams/ee4e416b-eb8d-4ae3-bf41-981de1adeae7/download |access-date=2025-12-18 |page=16}}</ref><ref name="NU2009birds" /> It is surrounded by papyrus swamp and a broad floodplain linked to the Apedura River, which drains parts of Karamoja toward the lake system.<ref name="NU2009birds" />
The lake is shallow. In field sampling between February 2008 and August 2009, depths at sampling locations ranged from 0.6 to 5.0 m, with an average of 2.89 m.<ref name="Gidudu2011" />
== Ramsar and Important Bird Area status == The '''Lake Bisina Wetland System''' was designated a Ramsar Site on 15 September 2006. The Ramsar Site covers 54,229 ha and is listed for Kumi, Katakwi and Soroti districts.<ref name="RamsarList2024">{{cite report |title=The List of Wetlands of International Importance (Ramsar Sites) |publisher=Ramsar Convention Secretariat |date=2024-11-22 |url=https://medwet.org/wp-content/uploads/2025/01/RamsarSitesList_22November2024.pdf |access-date=2025-12-18 |page=50}}</ref> Lake Bisina and the wider Bisina–Opeta wetland complex are also described as Important Bird Areas in Uganda’s site-based conservation work.<ref name="NU2009intro" />
== People and livelihoods == Communities around the Bisina–Opeta system rely on wetland resources. Local uses documented in baseline work include fishing, livestock watering, and harvesting of wetland materials, alongside expanding settlement and cultivation on marginal wetland areas.<ref name="NU2009intro" /> Baseline reporting also links increased siltation and reduced flood-buffer functions to land and catchment pressures, including degradation in upstream catchments feeding the system.<ref name="NU2009plants" />
==See also== *alt=Lake Bisinia|thumb|Photo of Lake Bisinia SwampKapir Atiira, village located near Lake Bisina *Lake Kyoga *Lake Opeta
== External links ==
*NatureUganda (2009) baseline report (PDF): https://nru.uncst.go.ug/bitstreams/ee4e416b-eb8d-4ae3-bf41-981de1adeae7/download
*Ramsar Sites List (22 November 2024) (PDF): https://medwet.org/wp-content/uploads/2025/01/RamsarSitesList_22November2024.pdf
==References== {{Reflist}}
{{Hydrography of Uganda}} {{Protected Areas of Uganda}}
{{DEFAULTSORT:Bisina}} Bisina Category:Ramsar sites in Uganda Category:Important Bird Areas of Uganda Category:Lakes of Uganda