It has declined in some rivers in southern Africa due to pollution, water abstraction and obstructions that prevent passage, such as dams and weirs. Unregulated gillnet fisheries locally threaten the species. Juveniles form an increasing component of the catches of fishers as other more valuable food fishes are fished out, most notably on the Barotse floodplains (D. Tweddle pers. obs. 2017). East African populations are threatened by heavy fishing pressure, silt loading due to agricultural activities or deforestation, and pollution due to pesticides for agricultural use. Threats in other regions are not known.
Name
Emma Hemmerlé
Scientific Name
Hydrocynus vittatus
Common Name(s)
Tigerfish
Type of Use
Non-Extractive
Are specific characteristics/traits being targeted?
Unknown/not recorded
Purpose of Use
Recreational
Additional Details (if available)
Hydrocynus vittatus is not popular as an eating fish and is generally not kept by recreational fisherman; however, it does form the basis of the catch-and-release (C&R) fishery in the Okavango Delta.
What is the main end use for any living organisms, parts or products taken/extracted?
In Botswana a recreational angling licence is a requirement for anglers visiting the area. The license stipulates that only five fish, regardless of species, may be kept daily. The remainder (including all juvenile and undersized fish) must be released.
The Okavango Delta is a subtropical floodplain, situated at the northern end of the Kalahari Desert in Botswana (Figure 1). During the seasonal floods, the delta fluctuates between 12 000–15 000 km2, and during the dry season between 6 000–8 000 km2 (Merron and Mann 1995). The study area (Figure 1) was situated in the panhandle region of the Okavango, just north of the Delta itself, close to the town of Shakawe and is characterised by slow-flowing, meandering water.
Local people (e.g., individuals, communities, co-operatives)
National external (individual, groups. e.g., hunters, anglers, photographers, tourists)
International external (individual, groups. e.g., hunters, anglers, photographers, tourists)
Is the use part of a strategy to generate conservation incentives, to finance conservation, or to improve tolerance/stewardship?
Unknown/not recorded
Is there evidence that the use is affecting the conservation status of the species? HIDE
No – no clear evidence of the impact of use compared to other factors influencing
Is there evidence that the use is affecting natural selection?
Unknown/not recorded
Is there evidence that the use is affecting poaching of illegal wildlife trade?
Unknown/not reported
Is there any evidence that this use of the species is having a knock-on effect on the status of non-target species
Unknown/not recorded
Unknown/not recorded
Details of assessment carried out
Angling and handling times along with nutritional status were likely influential factors in the range of glucose, cortisol and especially lactate levels in this study. These data suggest that C&R causes physiological stress to tigerfish, but could nonetheless be a valuable fisheries management tool, ensuring the sustainability of fish populations.
Has a valuation of financial flows from this use at the site/national/international level been recorded
Gerber, R., Howatson, G., Greenfield, R., Wagenaar, I., & Smit, N. (2017). Physiological response to angling of Africa’s premier freshwater angling species, the tigerfish Hydrocynus vittatus. African Zoology, 52(2), 91-98. doi: 10.1080/15627020.2017.1300069
Threats/pressures impacting the species at the scale of this record