Prey manipulation in a grassland community at an inland airport in South Africa

Terrestrial invertebrates and very small vertebrates were collected using pitfall and mouse traps in undisturbed long grass and grass which were kept permanently short over a period of 15 months (March 1994 – May 1995) at the Bloemfontein airport. Numerically insects contributed more than 90% of the overall sample. Twice as many individuals occurred in short grass compared to those in the long grass. The available food source for predominantly insectivorous avifauna at inland airports can thus be effectively reduced (indirectly also bird numbers) by implementing a so-called long grass policy as a control strategy. A significant and sustainable decrease in harvester termite numbers and activities was accomplished by administering bait treated with Gaucho in disturbed grass areas. As an important component in the diet of birds in grassland communities, bird numbers, and hopefully also bird aircraft strikes, can thus be reduced.

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Pacific Salmon: Ecology and Management of Western Alaska’s Populations

Pacific Salmon: Ecology and Management of Western Alaska’s Populations ◽

10.47886/9781934874110.ch4 ◽

2009 ◽

Keyword(s):

Food Source ◽

Driving Forces ◽

Pacific Salmon ◽

Late Summer ◽

Terrestrial Ecosystems ◽

Food Resources ◽

Growth And Survival ◽

Terrestrial Invertebrates ◽

Riverine Ecosystems ◽

Aquatic Food

<em>Abstract.</em>—Much is known about the importance of the physical characteristics of salmonid habitat in Alaska and the Pacific Northwest, with far less known about the food sources and trophic processes within these habitats, and the role they play in regulating salmonid productivity. Freshwater food webs supporting salmonids in Alaska rely heavily on nutrient, detritus, and prey subsidies from both marine and terrestrial ecosystems. Adult salmon provide a massive input of marine biomass to riverine ecosystems each year when they spawn, die, and decompose, and are a critical food source for young salmon in late summer and fall; riparian forests provide terrestrial invertebrates to streams, which at times comprise over half of the food ingested by stream-resident salmonids; up-slope, fishless headwater streams are a year-round source of invertebrates and detritus for fish downstream. The quantity of these food resources vary widely depending on source, season, and spatial position within a watershed. Terrestrial invertebrate inputs from riparian habitats are generally the most abundant food source in summer. Juvenile salmonids in streams consume roughly equal amounts of freshwater and terrestrially-derived invertebrates during most of the growing season, but ingest substantial amounts of marine resources (salmon eggs and decomposing salmon tissue) when these food items are present. Quantity, quality, and timing of food resources all appear to be important driving forces in aquatic food web dynamics, community nutrition, and salmonid growth and survival in riverine ecosystems.

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Rabbit warren distribution in relation to pasture communities in Mediterranean habitats: consequences for management of rabbit populations

Wildlife Research ◽

10.1071/wr04129 ◽

2005 ◽

Vol 32 (8) ◽

pp. 723 ◽

Cited By ~ 16

Author(s):

G. Gea-Izquierdo ◽

J. Muñoz-Igualada ◽

A. San Miguel-Ayanz

Keyword(s):

Spatial Distribution ◽

Selection Index ◽

Wild Rabbit ◽

Grassland Community ◽

Mediterranean Habitats ◽

The Mean ◽

Grassland Communities ◽

Shallow Soils ◽

Deep Soils ◽

The Relationship

Iberian wild rabbit numbers have decreased in the last decades. The management implemented to recover rabbit populations includes several techniques, one of the most common being the construction of artificial rabbit warrens. To optimally distribute the artificial warrens in the field it is essential to understand natural warren microhabitat. Few studies have investigated the relationship between rabbits and grassland communities. In this work we study the spatial distribution and characteristics of rabbit warrens as well as their relation to grasslands in Mediterranean woodlands of central Spain. During the summer of 2001, three 12.5-ha study plots, including the most representative grassland communities of the area, were selected. All rabbit warrens were surveyed and the active and total entrances, shrub cover, grassland community and warren cover type were characterised. A grassland community selection index was calculated and the warren spatial distribution analysed. Ploughed lands and shallow soils were unsuitable for warren establishment. The mean number of burrow entrances per warren was 5.8 (4.4 active), and warren clustering occurred only in ploughed plots. However, pasture communities composed of annual and perennial species growing on unploughed deep sandy soils were preferentially selected. Most warrens (81.4%) were dug under some kind of protection such as shrub roots and rocks. According to our results, when designing rabbit restocking programs that include the provision of artificial warrens, unploughed deep soils with plenty of shrubs and rocks should be preferentially selected to locate the artificial warrens, which should be spaced so there are ~10 warrens per hectare and ~5–6 burrow entrances per warren.

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Composition of the pristine grassland community in the Lowveld National Botanical Garden in Nelspruit, Mpumalanga, South Africa

South African Journal of Botany ◽

10.1016/j.sajb.2018.02.179 ◽

2018 ◽

Vol 115 ◽

pp. 325

Author(s):

T. Nevhutalu ◽

M.P. Tshisikhawe

Keyword(s):

South Africa ◽

Botanical Garden ◽

Grassland Community

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Levels of Elements in Typical Mussels from the Southern Coast of Africa (Namibia, South Africa, Mozambique): Safety Aspect

Water ◽

10.3390/w13223238 ◽

2021 ◽

Vol 13 (22) ◽

pp. 3238

Author(s):

Pavel Nekhoroshkov ◽

Jacques Bezuidenhout ◽

Inga Zinicovscaia ◽

Nikita Yushin ◽

Konstantin Vergel ◽

...

Keyword(s):

South Africa ◽

Food Source ◽

Mytilus Galloprovincialis ◽

Soft Tissues ◽

Hazard Indices ◽

The West ◽

Calculated Risk ◽

Permissible Levels ◽

Main Food Source ◽

Richards Bay

The soft tissues of mussels are often used as the main food source, especially in coastal areas. Neutron Activation Analysis was used to measure the content of 24 macro- and microelements in the soft tissues and 18 elements in the shells of selected sets of mussels of the species Mytilus galloprovincialis. The mussels were collected in 8 polluted and 4 pristine zones, which included Namibia, the west and east coasts of South Africa, and Mozambique. According to factor analysis Co, Ni, Zn, As, Se, Br, I, Sb could have anthropogenic origin. The concentrations of elements such as Cr, As, Se and partly Zn at polluted stations were above the maximum permissible levels for seafood. The concentrations of Sc, V, Cr, Mn, Co, Ni, Sb, Cs, Th, U in shells and soft tissues of the same mussels were at the close levels. Elements such as Al, Cr, Co, As (partly Zn, Se, and I) are considered to be harmful to human health at the levels of mussels consumption of 200 g/week per person and lower in such zones as Swakopmund, East London, Port Shepstone, Richards Bay, Xai-Xai according to calculated risk quotients and target hazard indices.

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The threats posed by the pet trade in alien terrestrial invertebrates in South Africa

Journal for Nature Conservation ◽

10.1016/j.jnc.2020.125831 ◽

2020 ◽

Vol 55 ◽

pp. 125831 ◽

Cited By ~ 2

Author(s):

Takalani Nelufule ◽

Mark P. Robertson ◽

John R.U. Wilson ◽

Katelyn T. Faulkner ◽

Catherine Sole ◽

...

Keyword(s):

South Africa ◽

Pet Trade ◽

Terrestrial Invertebrates

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The karst ecology of the Bakwena Cave (Gauteng)

Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie ◽

10.4102/satnt.v31i1.275 ◽

2012 ◽

Vol 31 (1) ◽

Cited By ~ 5

Author(s):

François Durand ◽

Antoinette Swart ◽

Werner Marais ◽

Candice Jansen van Rensburg ◽

Johan Habig ◽

...

Keyword(s):

South Africa ◽

Habitat Fragmentation ◽

Urban Development ◽

Plant Material ◽

Food Source ◽

Foraging Area ◽

Freshwater Amphipods ◽

Bacteria And Fungi ◽

Predatory Arthropods ◽

Bat Guano

The Bakwena Cave houses a variety of organisms that form an intricate and interdependent food web. This cave is utilised as a permanent roost by a colony of Natal clinging bats. The bat guano and allochthonous plant material that fall into the cave from outside, form the basis of the ecology inside the cave which may be considered a typical example of a detritus ecosystem. Decomposers such as bacteria and fungi are responsible for the decay of the guano and plant detritus which, in turn, are utilised by several organisms, including nematodes and mites, as food source. These animals form the next trophic level which is utilised by predatory arthropods as food source. The Bakwena Cave is one of the few dolomitic caves in South Africa that provide access to the water table. The groundwater houses several types of organisms, including bacteria, fungi and animals – primarily nematodes and crustaceans. The Bakwena Cave is also the type locality for freshwater amphipods in Southern Africa. This unique and sensitive ecosystem is primarily dependent on bat guano. The grassland surrounding the cave is utilised by the bats as foraging area and is currently threatened by urban development and the resulting habitat fragmentation and destruction. A cascade of extinctions of the cave-dwelling organisms will follow if the bats abandon the cave.

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Grassland communities of urban open spaces in Bloemfontein, Free State, South Africa

Koedoe ◽

10.4102/koedoe.v55i1.1075 ◽

2013 ◽

Vol 55 (1) ◽

Cited By ~ 9

Author(s):

Mamokete N.V. Dingaan ◽

Pieter J. Du Preez

Keyword(s):

South Africa ◽

Urban Environments ◽

Urban Vegetation ◽

Open Spaces ◽

Proper Management ◽

Species Analysis ◽

Twinspan Classification ◽

Natural Forms ◽

Grassland Biome ◽

Grassland Communities

Natural vegetation in urban environments is greatly impacted by human activities and it is in constant threat of degradation and destruction as a result of urbanisation. This vegetation, although fragmented, serves an important ecological function and needs to be properly managed and conserved. Studies on urban vegetation are lacking in South Africa, with only a handful having been carried out since the end of the last century. This study was initiated to identify, classify and describe the grassland communities of the urban open spaces in Bloemfontein. Relevés were compiled in 61 sample plots, where species present and habitat information were recorded. Care was taken to restrict sample plots to vegetation in pristine condition, wherever possible, and severely degraded stands were avoided. A two-way indicator species analysis (TWINSPAN) classification, refined by Braun-Blanquet procedures, revealed two distinct major communities, seven communities and four sub-communities. Both detrended and canonical correspondence analyses indicated the vegetation units to be associated with soil texture and pH, although biotic factors such as overgrazing, burning and mowing also influence the composition of the vegetation. The proper management and conservation of urban open spaces requires in-depth knowledge of the spatial distribution, floristic, structural and functional compositions within the major vegetation types in this environment. The present study further contributed towards formulating ways for the proper management, utilisation and functioning of the open spaces within the Bloemfontein area.Conservation implications: The Grassland Biome of South Africa is poorly conserved, mainly because of its status as an agricultural hub of the country. The preservation of natural and semi-natural forms of urban vegetation is important because such vegetation, although often disturbed and degraded, could form dispersal corridors between peri-urban and rural vegetation.

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