Invertebrate Specialist Report – December 2014 Reedbeds (Phragmites mauritianus) occur in dense stands along some sections of the Revuboe River (Plates 2.5 & 2.6). It is the preferred habitat for a number of specialised species such as the Lesser Swamp Warbler (Acrocephalus gracilirostris), while also providing important roosting habitat for certain dryland species (e.g. weavers, bishops, swallows). Plate 2.6 Typical reed beds found on site Granite outcrops generally occur on the hills in the region and are characterised by large boulders and a dense woody cover in the form of Closed Zambezian Undifferentiated Woodland (refer to Plates 2.2 & 2.7). It provides important habitat for rupiculous (rock loving) species such as certain birds and reptile species. These habitats will be largely impacted on, as they are located on the hills which will become the mine pits Plate 2.7: Rocky outcrops typically occur on ridges amongst Closed Zambezian Undifferentiated Woodland Coastal & Environmental Services (Pty) Ltd 3 Tete Iron Ore Project Invertebrate Specialist Report – December 2014 Dambos occur as linear open areas of hydrophilic grasslands with rushes and sedges, which contrast with surrounding woodland, in this case the mopane woodlands (Figure 2.1 and Plate 2.8). A Dambo is essentially is a plateau wetland, which is “a seasonally waterlogged, predominantly grass-covered, depression (i.e. vlei)”. They may be substantially dry at the end of the dry season, revealing grey soils or black clays, but unlike flooded grassland, they retain wet lines of drainage through the dry season. They are inundated (waterlogged) in the wet season but not generally above the height of the vegetation and any open water surface is usually confined to streams, rivers and small ponds or lagoons at the lowest point, generally near the centre. Parts of the dambos will be affected unless certain infrastructure is re-located, especially the Ruoni south waste dump, and the TSF (refer to Figure 2.1). Plate 2.8: A typical dambo which can be found on site. Coastal & Environmental Services (Pty) Ltd 4 Tete Iron Ore Project Invertebrate Specialist Report – December 2014 3. METHODS 3.1. Terrestrial Invertebrate sampling methodology 3.1.1. Assessment approach We believe that the core of any environmental/biodiversity assessment must be a rigorous, effective and efficient sampling protocol - no amount of hi-tech equipment, specialised software, complex analysis and fancy presentation can make up for inadequately designed or poorly executed sampling. Our approach is thus: 1) to survey, in a quantified manner and using internationally accepted sampling protocols where available, several invertebrate taxa - such as ants, butterflies, ground beetles, leafhoppers and termites - that are recognised as biodiversity and ecological indicators were used. Some methods may be impractical in certain areas (e.g. wetlands and wetland fringes) and some taxa will occur only in particular habitats, so not all methods and taxa are necessarily covered for each project or site. The data obtained for these groups can then be used as a sound baseline to set rehabilitation targets, against which to measure the success of restoration processes. 2) where appropriate, to survey for red-listed, rare or sensitive species (SCC) in the indicator taxa as well as in other groups such as mygalomorph spiders, scorpions, dragonflies and damselflies. While no standardised protocols exist for sampling several of the indicator taxa we have selected, many years combined experience of ant sampling was brought together under the auspices of the IUCN in the formulation of the Ants of the Leaf Litter (ALL) protocol (Agosti et al. 2000). This provides a defined sampling protocol to be applied worldwide and hence allows meaningful comparisons of the ant fauna of geographically widely separated sites. We have chosen this protocol as the basis for our sampling and, although there are some modifications and additions to the sampling methods to allow effective sampling of other taxa, the ant data produced are compatible with other ALL protocol datasets from around the world. Our protocol is consistent with IFC Performance Standard 6 (IFC 2012) and provides detailed information equally applicable to assessment of relative sensitivities of sites and to monitoring of project impacts or restoration progress over time: for a given level of required confidence in predictions the same level of sampling is required whether communities are being assessed in terms of differences over time or space. 3.1.2. Focal taxa for invertebrate survey A wide range of invertebrate taxa were proposed as invertebrate indicators in the scoping report (Ekoinfo 2012): Scorpions (Arachnida: Scorpiones) Spiders (Arachnida: Araneae) Millipedes (Diplopoda) Damselflies and Dragonflies (Insecta: Odonata) Bugs (Insecta: Hemiptera) Antlions (Insecta: Neuroptera) Beetles (Insecta: Coleoptera) Butterflies (Insecta: Lepidoptera) Ants (Insecta: Hymenoptera – Formicidae) However, given the huge diversity within many of these taxa, it would be prohibitively costly and time-consuming to effectively evaluate all of these in the course of an EIA survey; a more limited subset of these groups was thus selected, based on prior experience of suitability as indicators, Coastal & Environmental Services (Pty) Ltd 5 Tete Iron Ore Project Invertebrate Specialist Report – December 2014 ease of sampling and reliability of identifications. Three groups were omitted entirely from focussed sampling, while a subset of the proposed taxonomic group was selected in the case of another two groups (spiders and bugs). The taxa on which the present surveys were focused were thus: Scorpions (Arachnida: Scorpiones) Mygalomorph Spiders (Arachnida: Araneae, Mygalomorphae) Damselflies and Dragonflies (Insecta: Odonata) Leafhoppers (Insecta: Hemiptera, Cicadellidae) Butterflies (Insecta: Lepidoptera) Ants (Insecta: Hymenoptera – Formicidae) Sampling of other taxa, including groups such as Neuroptera (antlions, owlflies etc), cicadas (Hemiptera: Cicadidae) and beetles (Coleoptera), was carried out on an ad hoc basis when specimens of potential interest were encountered. 3.1.3. Detailed description of sampling methods Site visits A wet season site visit was carried out from 15-27 March 2013, but due to cessation of rain and high temperatures, conditions were drying rapidly so that for many taxa lower activity levels more typical of the dry season were apparent by the end of the surveys and dry season forms of several butterfly species were observed. Unfortunately earlier sampling was not feasible, as access to the site in the rainy season is very challenging, and river crossings impossible. A dry season site visit was carried out from 3-9 September 2013, during which further butterfly and Odonata sampling was carried out as well as focussed follow-up surveys for taxa of importance noted during the wet season survey. An additional late wet season visit was undertaken from 10-17 April 2014, with the main aim being to survey the newly proposed Haul Road 6, although the opportunity was also taken to carry out some additonal surveys on Tenge Hill and in the mopani woodland site (between the proposed ROM and TSF sites) studied in 2013. Sampling protocol The planned sampling of terrestrial invertebrates at the project site aimed at surveying a representative area of each main habitat type using a detailed sampling protocol that would enable both a sensitivity assessment and a baseline measure of biodiversity in key indicator groups to allow monitoring of impacts and rehabilitation. The core of the ALL protocol, from which the sampling was developed, is the collection and analysis of twenty 2-litre leaf litter samples and twenty 48-hour pitfall trap samples collected at 10 metre intervals along a 190 metre transect at each site to be surveyed; this is estimated to generally result in an approximately 70 percent complete inventory of the ant fauna, with sufficient predictive power to reliably estimate the total number of ant species using software such as EstimateS (Colwell 2013). After consideration of the habitats present and in order to allow similar data to be obtained for other indicator taxa in the Baobab Iron Ore Project site, we used the following methods, which included some additions and modifications to the ALL protocol, at each of the four sites that were surveyed in detail during the wet season site visit: Leaf litter samples were omitted due to the extremely stony nature of the soil at three of the four survey sites; standard leaf litter sampling requires chopping of the leaf litter and surface soil layers with a sharp panga (machette) and this was not possible under the conditions encountered. Low daytime surface activity of ants due to the rapidly drying leaf litter layer after the end of the rainy season meant that the alternative of collecting and Coastal & Environmental Services (Pty) Ltd 6 Baobab Resources (Pty) Ltd Invertebrate Specialist Report – December 2014 sifting un-chopped surface litter (which was tested at the Tenge Hill site) did not yield adequate samples. Twenty 48-hour pitfall trap (see Figure 3.1) samples, with traps set at 10 metre intervals along a 190 m transect, Twenty 20-minute hand-collected ant samples, each along a transect of up to 50m in length starting near to one of the pitfall traps, Two full person-days of hand-netting for butterflies, dragonflies and damselflies, Ten 1-day fermenting-banana baited trap (see Figure 2.2) butterfly