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Location Tunisia, Sfax
Central coordinates 10o 19.00' East  34o 24.00' North
IBA criteria A3, A4i, A4iii
Area 5,850 ha
Altitude 0 - 3m
Year of IBA assessment 2001

Association "Les Amis des Oiseaux"

Site description Located 50 km south of the town of Sfax and 25 km south-east of Mahares, Kneiss is a large area of wetland in the Gulf of Gabès. The site includes the surrounding semi-desert grasslands, the shoreline, intertidal flats and five offshore islands. The vegetation of the main island of Djeziret Bessila (650 ha) is composed of halophytic species including Halocnemum, Arthrocnemum and Suaeda species.

Key Biodiversity See Box and Table 2 for key species. The Gulf of Gabès in general, with its tidal range of up to two metres and its extensive mudflats at low water, is one of the most important sites in Tunisia for waders and piscivorous waterbirds, both on migration and in winter. The Kneiss islands and the shoreline opposite at Oued Maltine, is the ornithological centre-point of the Gulf of Gabès, but many of the typical species may also be found at other sites in the Gulf such as Kerkennah (site TN026), Thyna (TN027), Akarit (TN034), Bordj Kastil (TN036), Gourine (TN037) and Boughrara (TN038). The tidal mudflats provide habitat for wader species that otherwise occur only in small numbers in the Mediterranean, such as Ostralegus haematopus, Arenaria interpres, Pluvialis squatarola, Numenius arquata, Limosa lapponica, Calidris canuta and Limicola falcinellus, some of which have their only major Mediterranean wintering grounds in the Gulf. Some waders breed, notably Charadrius alexandrinus, Recurvirostra avosetta, Himantopus himantopus and Tringa totanus; the latter is particularly interesting since it scarcely breeds at all in northern and central Tunisia, and thus the breeding population in the Gulf of Gabès is isolated from others further north. Other trans-Saharan migrant waders such as Calidris minuta, C. alba and C. ferruginea occur in large numbers on passage, and some stay to winter; this is the only area in the Mediterranean with considerable numbers of wintering C. ferruginea.The Gulf of Gabès is also notable for its wintering Platalea leucorodia (most of the central European breeding population winters here), and for wintering Casmerodius albus, Ardea cinerea and Egretta garzetta. There are ground-nesting colonies of E. garzetta. Among gulls and terns, large numbers of Larus melanocephalus and L. genei, mostly originating from Black Sea colonies, winter and there are some breeding colonies of L. genei. Wintering terns include Sterna sandvicensis and S. caspia in good numbers, with breeding colonies of S. nilotica, S. albifrons and S. hirundo (the latter, like Tringa totanus, only breeds in any numbers in the Gulf of Gabès and is thus isolated from more northerly breeding colonies). S. bengalensis occurs in small numbers on passage, and has been suspected of breeding.The above paragraphs refer to the Gulf of Gabès in general. Kneiss is the most important area, since it has the largest area of mudflats, the most important high-tide wader roosts, and some of the major breeding colonies. It is also the most important wintering area for waders in the Mediterranean, numbers of which can reach 330,000. The islands hold breeding populations of Egretta garzetta, Tringa totanus, Larus cachinnans, Sterna hirundo and S. albifrons. There are also historical records of Numenius tenuirostris.

Non-bird biodiversity: None known to BirdLife International.

Populations of IBA trigger species

Species Season Period Population estimate Quality of estimate IBA Criteria IUCN Category
Greater Flamingo Phoenicopterus roseus winter  600-7,000 individuals  A4i  Least Concern 
Eurasian Spoonbill Platalea leucorodia winter  200-1,000 individuals  A4i  Least Concern 
Haematopus ostralegus winter  10,000-20,000 individuals  A4i  Not Recognised 
Charadrius alexandrinus winter  5,000-10,000 individuals  A4i  Not Recognised 
Grey Plover Pluvialis squatarola winter  1,000-32,500 individuals  A4i  Least Concern 
Common Ringed Plover Charadrius hiaticula winter  3,000-10,000 individuals  A4i  Least Concern 
Common Redshank Tringa totanus winter  40,000 individuals  A4i  Least Concern 
Black-tailed Godwit Limosa limosa winter  2,000-7,000 individuals  A4i  Near Threatened 
Bar-tailed Godwit Limosa lapponica winter  2,000-5,000 individuals  A4i  Near Threatened 
Eurasian Curlew Numenius arquata winter  800-6,000 individuals  A4i  Near Threatened 
Ruddy Turnstone Arenaria interpres winter  600-4,000 individuals  A4i  Least Concern 
Little Stint Calidris minuta winter  5,000-8,000 individuals  A4i  Least Concern 
Dunlin Calidris alpina winter  125,000 individuals  A4i  Least Concern 
Curlew Sandpiper Calidris ferruginea winter  3,000-9,625 individuals  A4i  Near Threatened 
Sterna nilotica breeding  250-400 breeding pairs  A4i  Not Recognised 
Larus cachinnans winter  600-8,000 individuals  A4i  Not Recognised 
Slender-billed Gull Larus genei winter  1,000-2,500 individuals  A4i  Least Concern 
Sandwich Tern Thalasseus sandvicensis winter  1,000-3,000 individuals  A4i  Least Concern 
Red-necked Nightjar Caprimulgus ruficollis breeding  1999  present  A3  Least Concern 
Temminck's Lark Eremophila bilopha resident  1999  present  A3  Least Concern 
Spectacled Warbler Sylvia conspicillata resident  1999  present  A3  Least Concern 
Sardinian Warbler Sylvia melanocephala resident  1999  present  A3  Least Concern 
Spotless Starling Sturnus unicolor resident  1999  present  A3  Least Concern 
Black Wheatear Oenanthe leucura resident  1999  present  A3  Least Concern 
Red-rumped Wheatear Oenanthe moesta resident  1999  present  A3  Least Concern 
Black-eared Wheatear Oenanthe hispanica breeding  1999  present  A3  Least Concern 
A4iii Species group - waterbirds winter  100,000-499,999 individuals  unknown  A4iii   

IBA Monitoring

2009 medium very unfavourable medium
Medium - based upon reliable but incomplete / partially representative data

Biological resource use hunting & collecting terrestrial animals - intentional use (species being assessed is the target) happening now some of area/population (10-49%) slow but significant deterioration medium
Climate change and severe weather drought likely in long term (beyond 4 years) majority/most of area/population (50-90%) slow but significant deterioration medium
Energy production and mining oil and gas drilling likely in short term (within 4 years) some of area/population (10-49%) slow but significant deterioration medium
Human intrusions and disturbance work and other activities happening now some of area/population (10-49%) slow but significant deterioration medium

Phoenicopterus roseus Greater Flamingo 1325 3968 individuals 100 favourable
Platalea leucorodia Eurasian Spoonbill 120 185 individuals 100 favourable
Charadrius alexandrinus 660 3168 individuals 100 favourable
Pluvialis squatarola Grey Plover 2500 3690 individuals 100 favourable
Charadrius hiaticula Common Ringed Plover 730 99 individuals 14 very unfavourable
Tringa totanus Common Redshank 2500 11600 individuals 100 favourable
Limosa lapponica Bar-tailed Godwit 1200 251 individuals 21 very unfavourable
Numenius arquata Eurasian Curlew 8500 2950 individuals 35 very unfavourable
Arenaria interpres Ruddy Turnstone 1500 368 individuals 25 very unfavourable
Calidris minuta Little Stint 2000 18200 individuals 100 favourable
Calidris alpina Dunlin 13300 50800 individuals 100 favourable
Calidris ferruginea Curlew Sandpiper 10000 4580 individuals 46 unfavourable
Larus genei Slender-billed Gull 1700 982 individuals 58 unfavourable

Whole area of site (>90%) covered by appropriate conservation designation  A management plan exists but it is out of date or not comprehensive  Substantive conservation measures are being implemented but these are not comprehensive and are limited by resources and capacity  medium 

Protected areas

Protected area Designation Area (ha) Relationship with IBA Overlap with IBA (ha)  
Iles Kneiss Nature Reserve 5,580 protected area contains site 5,850  

Local conservation groups The local conservation group below is working to support conservation at this IBA.

Name Year formed
AAO/ Sfax Regional Branch 2000

Land use

Land-use Extent (% of site)
nature conservation and research -

References Gaultier (1988a), Groupe Internationale pour Recherche des Oiseaux d’eaux et des Zones Humides (1994), Meininger et al. (1994), Ministère de l’Agriculture, Direction Générale des Forêts (2000), Oueslati (1995), van der Have et al. (1994), van Dijk et al. (1986).

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Recommended citation  BirdLife International (2016) Important Bird and Biodiversity Area factsheet: Kneiss. Downloaded from on 24/10/2016

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