KwaZulu-Natal Mistbelt Grasslands

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General Information

Status:

Global IBA (A1)

Province:

KwaZulu-Natal

Protection:

Unprotected

Size:

29 410 ha

Number:

SA078

Additional Info

  • Site description

    This IBA consists of a series of disconnected grassland patches on farms located in the KwaZulu-Natal Midlands. The total extent of the patches adds up to 29 410 ha. The region is roughly bounded in the west by the Umtamvuna River; in the south and east by the 900-m a.s.l. contour line (below this the climate is too warm and dry for mistbelt grassland); and in the north by high ground above about 1 300 m a.s.l. (where the climate becomes too cold for mistbelt grassland). The terrain is rolling hills dissected by rivers and streams. Soils are often deep, allowing small streams to run underground, and sinkholes are a typical feature. The altitude (of the patches within the IBA, as intervening ground may have lower-lying valleys) ranges from 920 to 1 340 m a.s.l. The principal vegetation is (or was before most of it was transformed) Midlands Mistbelt Grassland. The farms listed support viable units of mistbelt grassland and pairs of Blue Swallows Hirundo atrocaerulea, and are important for the conservation of grassland birds in the district. The climate is temperate. Mist is frequent in summer, as is frost in winter. Rainfall averages 900–1 150 mm p.a.

    Birds

    This area holds one of the highest concentrations of Blue Swallows in the southern African sub-region. At least 30 nests are known, and additional sites are likely in areas that have not yet been properly explored. Denham's Bustard Neotis denhami occurs and two traditional lekking sites are located here. A Southern Bald Ibis Geronticus calvus colony is located on the Umzimkulu cliffs. Blue Crane Anthropoides paradiseus and Grey Crowned Crane Balearica regulorum nest in the district.

    The open grasslands support Secretarybird Sagittarius serpentarius, Black-winged Lapwing Vanellus melanopterus, Corn Crake Crex crex, Black-rumped Buttonquail Turnix nanus and Striped Flufftail Sarothrura affinis.

    IBA trigger species

    The primary reason for the IBA having been declared is its breeding population of globally threatened Blue Swallows, with between 30 and 35 pairs breeding and a total of c. 100–150 individuals. Other globally threatened species are Southern Bald Ibis, with a breeding colony of up to 30 pairs, Martial Eagle Polemaetus bellicosus, Denham's Bustard, Blue Crane (breeding), Grey Crowned Crane, Southern Ground-Hornbill Bucorvus leadbeateri (at least three breeding groups), Secretarybird and Yellow-breasted Pipit Anthus chloris. Regionally threatened species are African Marsh Harrier Circus ranivorus, Striped Flufftail and African Grass Owl Tyto capensis.

    Other biodiversity

    Important mammals include the oribi Ourebia ourebi and the aardvark Orycteropus afer, which Blue Swallows rely on to create nesting holes. The mistbelt chirping frog Anhydrophryne ngongoniensis is a highly localised and Critically Endangered endemic to this habitat and the Endangered long-toed tree frog Leptopelis xenodactylus is also known to occur. Invertebrate life is rich, and two new endemic earthworms – Proandricus bulwerensis and P. adriani – have recently been discovered. Mistbelt grassland is noted for its diversity of flowering plants and their high level of endemism. Rarities typical of, or confined to, the Ixopo area – the heart of the Blue Swallow range in KwaZulu-Natal – include Satyrium rhodanthum, Gerbera aurantiaca, Dierama nixonianum and Helichrysum citricephalum.

    Conservation issues

    Threats

    The area consists of privately owned farmland, communally owned land and forestry land. Because the land was ideal for farming, no provision for formal conservation was made. Nevertheless, the way in which the land was used allowed most wildlife to survive. Cattle grazing, for example, is a land use entirely compatible with the well-being of the Blue Swallow. However, much of the land has been converted to pasture or growing maize to feed dairy cows. In addition, since 1950 timber has been more profitable than dairy farming and the trend towards afforestation has accelerated since the 1980s. The climate and soils of the Midlands Mistbelt are exceptionally favourable for timber and there is great incentive for farm owners to sell their properties, or lease parts of them, to paper mill giants for the growing of plantations. Much of the region has now been converted into timber monoculture. This is the most direct threat to the largest Blue Swallow population remaining in KwaZulu-Natal.

    To a fair extent in practice, objections to planting for reasons of nature conservation are taken seriously. Nevertheless, at most 6% of the original habitat suitable for Blue Swallows in the Ixopo area remains. If strict criteria are used and habitat fragments too small or isolated to be of use are excluded, perhaps only 3% remains. Conversations with older farmers reveal that the areas that are now under timber but are presumed to have been suitable for Blue Swallows did indeed support the species before timber was planted.

    Conversion of old timberlands back to something resembling grassland is a possibility. However, this would be very difficult, given the propensity for alien weeds to invade such degraded habitat. This has not been attempted yet. Another real problem, and one that is only just beginning to be understood, is that most of the holes used by Blue Swallows for nesting are created by aardvarks. Not only are these animals now rare, but their mobility is restricted by roads and alien habitats. So grassland fragments that are apparently suitable for Blue Swallows remain unused because there is no longer a supply of fresh nest holes. Existing holes have a limited life span, generally collapsing after 5–10 years. Natural sinkholes must be rarer than formerly. In addition, timber plantations that use large amounts of water cause stream flow to be reduced or even to cease altogether. New underground channels are therefore not likely to be created. One solution to the shortage of nest holes is for interested landowners to dig substitute holes. This measure has already had some success and may contribute to conserving the Blue Swallow in the short term.

    Apart from the presence of the Blue Swallow, these grasslands merit conservation in their own right. Midlands Mistbelt Grassland is endemic to KwaZulu-Natal, yet its conservation status is one of the poorest of all KwaZulu-Natal veld types. Only 47% of the original extent of this habitat type remains.

    Conservation action

    Conservation activities centring on the Blue Swallow are co-ordinated by the Blue Swallow Working Group, whose members come from BirdLife South Africa, EWT, EKZNW and forestry companies or are private landowners. Through Biodiversity Stewardship initiatives, private landowners are entering into agreements to formally declare land. Most recently, Roselands, which supports 3–4 pairs of Blue Swallows, was designated a nature reserve. A Biodiversity Stewardship officer is also currently working with other landowners in the district. In order to conserve the species, it is imperative that the last remaining habitat where Blue Swallows occur is managed for conservation, and Biodiversity Stewardship is a way to do this. All known Blue Swallow nests are monitored each year by EKZNW, with help from members of the Blue Swallow Working Group. A niche model has also been developed and ground truthing is being undertaken to investigate other areas that may potentially support Blue Swallow.

    Related webpages

    www.kznwildlife.com

    Contact

    If you have any information about the IBA, such as a new threat that could impact on it, please send an e-mail to iba@birdlife.org.za or call BirdLife South Africa +27 (11) 789 1122.

    Page last updated

    Monday, 09 February 2015

    Further Reading

    Combrink L, Little L (eds). 2013. Review of the Blue Swallow International Action Plan and Regional Red List Assessments. International Workshop Summary. Endangered Wildlife Trust.

    Evans SW, Bouwman H. 2009. Habitat selection by blue swallows Hirundo atrocaerulea Sundevall, 1850 breeding in South Africa and its implications for conservation. African Journal of Ecology 48: 871–879.

    Evans SW, Bouwman H. 2010. Historical and current distribution, population size, and possible migration routes of the Blue Swallow Hirundo atrocaerulea in Africa. Bird Conservation International. 20: 1–15.

    Johnson DN, Morford JS, Croft M. 1996. Digging for the Blue Swallow – does it work? Is it ethical? Lammergeyer 44: 46–49.

    Marchant A. 2012. Ezemvelo KZN Wildlife Monitoring Plan: Blue Swallow. Ezemvelo KZN Wildlife.

    Marchant A. 2013. Status of Blue Swallow in KwaZulu-Natal: 2012–2013 breeding season, with comparisons to historical data. Ezemvelo KZN Wildlife.

    Savy C. 2003. Conserving Wattled Crane (Grus carunculatus) on private land in KwaZulu-Natal, South Africa: attitudes, economics and potential incentives. MSc thesis, University of Cape Town, South Africa.

    Scott-Shaw CR, Bourquin O, Porter RN. 1996. The conservation status of Acocks veld types in KwaZulu-Natal. Lammergeyer 44: 50–63.

    Wakelin J. 2006. An investigation to determine the critical habitat requirements of the breeding Blue Swallow Hirundo atrocaerulea. MSc thesis, University of KwaZulu-Natal, South Africa.

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