scholarly journals The alien invasive land snail Theba pisana in the West Coast National Park: Is there cause for concern?

Koedoe ◽  
2008 ◽  
Vol 50 (1) ◽  
Author(s):  
Lizelle J. Odendaal ◽  
Tanya M. Haupt ◽  
Charles L. Griffiths
Keyword(s):  
West Coast ◽  
National Park ◽  
Feeding Habits ◽  
Activity Patterns ◽  
Average Density ◽  
Land Snails ◽  
Adult Size ◽  
The West ◽  
Theba Pisana ◽  
Very High

The distribution, abundance, size distribution and diurnal activity patterns of invasive land snails, Theba pisana, in the West Coast National Park (WCNP), South Africa, were investigated. The park was divided into 1 km2 grids, within each of which five 1 m2 quadrat counts of live snails were recorded. Of 106 grids sampled, 19% contained live snails. The average density of snails was 4.04 m-2 ± 24.9, significantly lower than in disturbed habitats adjacent to the park (57 m-2 ± 96.25), but very high densities were recorded at two sites. Snails were most abundant along roadsides and densities decreased dramatically with distance from roads. T. pisana in the WCNP appear to have an annual lifecycle, breeding in autumn to winter and growing to adult size of about 14 mm diameter by the end of the following summer. Snails were observed on a wide variety of endemic and introduced plant species and appeared to have a catholic diet. They are active mostly at night and especially during periods of high humidity, irrespective of temperature. Given the very high densities that T. pisana can attain at some sites, plus their apparently catholic feeding habits, their potential impact on the vegetation of the park is cause for concern and should be further investigated. Control of the main colonies should also be considered.

scholarly journals Acrobeles farzanae spec. nov. and Seleborca complexa (Thorne) from the West Coast National Park and Rocher Pan Nature Reserve (Nematoda: ephalobidae)

Koedoe ◽  
1995 ◽  
Vol 38 (2) ◽  
Author(s):  
J. Heyns
Keyword(s):  
South Africa ◽  
New Species ◽  
Body Length ◽  
West Coast ◽  
National Park ◽  
Additional Data ◽  
Nature Reserve ◽  
The West ◽  
Lateral Field

Acrobeles fananae spec. nov. is described from two localities on the west coast of South Africa. The new species is characterised by body length of 0.7-0.8 mm; relatively slender, cylindroid body, abruptly ventrally bent in vulval region; vulva with protruding lips and situated in a sunken area; three incisures in lateral field; and cuticle with an intricate interlocked block-like pattern. Additional data is presented on the morphology of Seleborca complexa (Thorne, 1925) collected in the same area.

Feeding Habits of Pacific cod (Gadus macrocephalus) in the West Coast of Yellow Sea of Korea

2019 ◽  
Vol 31 (2) ◽  
pp. 77-82
Author(s):  
Dong-Hyek Choi ◽  
Myoung-Ho Sohn ◽  
Maeng Jin Kim ◽  
Seung-Jong Lee
Keyword(s):  
West Coast ◽  
Yellow Sea ◽  
Feeding Habits ◽  
Pacific Cod ◽  
The West ◽  
Pacific Cod Gadus Macrocephalus ◽  
Gadus Macrocephalus

A taxonomic revision of Maurocenia (Celastraceae), a Western Cape monotypic endemic

Bothalia ◽  
1998 ◽  
Vol 28 (1) ◽  
pp. 7-10 ◽  
Author(s):  
R. H. Archer ◽  
A. E. Van Wyk
Keyword(s):  
West Coast ◽  
National Park ◽  
Taxonomic Revision ◽  
Western Cape ◽  
Restricted Range ◽  
Monotypic Genus ◽  
The West ◽  
The Past ◽  
Cape Peninsula ◽  
African Genus

A taxonomic account is given of the monotypic genus Maurocenia Mill. Maurocenia frangula Mill, has a restricted range and is endemic to the Cape Peninsula and the West Coast National Park. Western Cape. Maurocenia frangularia (L.)Mill., the species name and author citation widely used in the past, is incorrect. It is characterized by. among others, pendulous ovules and gynodioecy, rare states in the Celastraceae. Maurocenia is apparently most closely related to the southern African genus Lauridia Eckl. Zeyh.

scholarly journals Investigating the effects of management practice on mammalian co-occurrence along the West Coast of South Africa

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8184
Author(s):  
Deborah Jean Winterton ◽  
Nicola J. van Wilgen ◽  
Jan A. Venter
Keyword(s):  
West Coast ◽  
Protected Area ◽  
National Park ◽  
Spatial Information ◽  
Management Practice ◽  
Interspecific Interactions ◽  
Camera Traps ◽  
Sufficient Evidence ◽  
The West ◽  
Cascading Effects

The subtle and cascading effects (e.g., altered interspecific interactions) that anthropogenic stressors have on local ecological assemblages often go unnoticed but are concerning given their importance in ecosystem function. For example, elimination of buffalo from the Serengeti National Park is suggested to have driven increased abundance of smaller antelope as a result of release from competition. The perceived low abundance of small antelope in the contractual Postberg section of the West Coast National Park (the park) has been an ongoing management concern which has been anecdotally attributed to predation by a mesopredator (the caracal, Caracal caracal). However, we hypothesized that the historical overstocking, and consequent overgrazing by larger-bodied managed ungulates would influence small antelope abundance. Using camera traps, we investigated species co-occurrence and temporal activity between small antelope, managed ungulates and caracals in Postberg as well as another part of the park (Langebaan) and a farm outside of the park. Results suggest that small antelope and managed ungulates have a high degree of temporal overlap (Δ = 0.74, 0.79 and 0.86 for the farm, Langebaan and Postberg respectively), while temporal partitioning between small antelope and caracal is apparent (Δ = 0.59). Further, small antelope and managed ungulates appear to occur independently of one another (SIF = 0.91–1 across areas). Managed ungulates were detected almost three times more frequently on fallow lands when compared to the more vegetated sites within the park suggesting that segregated food/cover resources allow for independent occurrence. Small antelope had a much higher probability of occurrence outside of the protected area (e.g., ψ = 0.192 and 0.486 for steenbok at Postberg, Langebaan compared to 0.841 on the farm), likely due to less variable (more intact) habitat outside of the protected area. There is not sufficient evidence to currently warrant management intervention for predators. The small size of the protected area provides limited scope for spatial replication thus reducing possibilities to infer the cause and effect for complex interactions (which would historically have taken place over much larger areas) with negative implications for adaptive management. We recommend continued monitoring over multiple seasons and a wider area to determine the spatial information requirements to inform management of small protected areas.

scholarly journals Coastal Vulnerability of the West Coast of Aceh Besar: A Coastal Morphology Assessment

2021 ◽  
Vol 9 (8) ◽  
pp. 815
Author(s):  
Muhammad Irham ◽  
Ichsan Rusydi ◽  
Haekal A. Haridhi ◽  
Ichsan Setiawan ◽  
Yopi Ilhamsyah ◽  
...  
Keyword(s):  
West Coast ◽  
Geographical Information Systems ◽  
Vulnerability Index ◽  
High Elevation ◽  
Sandy Beaches ◽  
Geographical Information ◽  
Coastal Vulnerability ◽  
The West ◽  
Coastal Morphology ◽  
Very High

The purpose of this study was to determine how vulnerable the west coast of Aceh Besar, Aceh province, Indonesia, is in terms of its coastal morphology. This research was conducted from August to December 2020 and data processing was carried out at the Geographical Information Systems Laboratory, Faculty of Marine Affairs and Fisheries, Syiah Kuala University. The method used was the coastal vulnerability index (CVI) with four geological parameters, namely geomorphological parameters, beach elevation, beach slope and shoreline changes. The results obtained from the CVI method show that 20.60% of the west coast of Aceh Besar, which has a total coastline length of 93.2 km, is in the very high vulnerability category (19.2 km), while 23.18% (21.6 km) is in the high vulnerability category, 8.80% (8.2 km) in the moderate category, 6.44% (6 km) in the low category and 40.99% (38.2 km) in the very low category. Sub-districts classified as having very high vulnerability are Peukanbada (7.94%), Leupung (6.22%), Lhoong (4.94%), and Lhoknga (1.50%). The geomorphology of areas that have very high vulnerability is generally in the form of sandy beaches with a very gentle slope, while, geomorphologically, areas that have very low vulnerability have a high elevation and cliff beaches.

scholarly journals A checklist of land snails from the west coast islands of Sabah, Borneo (Mollusca, Gastropoda)

ZooKeys ◽  
2017 ◽  
Vol 673 ◽  
pp. 49-104 ◽  
Author(s):  
Chee-Chean Phung ◽  
Fred Tuh Yit Yu ◽  
Thor-Seng Liew
Keyword(s):  
West Coast ◽  
Land Snails ◽  
The West

scholarly journals Low to very high temperature thermal energy recycling – 3 case studies

2021 ◽  
Vol 313 ◽  
pp. 09001
Author(s):  
Arne Høeg ◽  
Tor-Martin Tveit
Keyword(s):  
High Temperature ◽  
Heat Source ◽  
Case Studies ◽  
Heat Pump ◽  
Thermal Energy ◽  
West Coast ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
The West ◽  
Very High

In this paper we present three case studies of the installation of a stirling-cycle high temperature heat pump applied to recycling thermal energy including steam generation. Many industries have heat demand at temperatures above 100°C and often the preferred energy carrier is steam. The optimal integration of a heat pump can be determined by investigating the thermal need of the process with pinch technology. For many industries, the pinch temperature is too high for conventional heat pumps. We present a heat pump solution that can recycle thermal energy and deliver this to a heat source up to 200°C, as hot water or steam. The heat pump can be integrated in a thermodynamic efficient way placing the sink and source in-between the pinch temperature. The working medium is a gas throughout the process cycle, with no evaporation or condensation. Thus, the process can auto-adjust to temperature variations and achieve very high efficiencies compared to the Carnot heat pump cycle. The coefficient of performance (COP) of the heat pump vary with the sink/source temperatures as the temperature fraction varies. Another important feature is that the medium has both a global warming potential (GWP) and ozone depletion potential (ODP) of zero. The thermodynamics of the heat pump is explained in more detail in the introduction section. The first installation is at a dairy plant on the west coast of Norway. In this installation, the heat pump provides cooling at 0-5°C and converts this heat into hot water at 120°C. The second installation is also at a dairy in Norway. Here the heat pump cools the ammonia from the cooling compressors at about 25-30°C and converts the heat to hot water at 110C°. The third installation is at a beverage plant on the west coast of Norway. Here the heat pump is providing cooling to compressors and other equipment. The final temperature of the heat source varies from 20-70°C. The heat is converted into steam at 168°C. In the case study sections, the installations are discussed in more details, together with the performance and a discussion of the experiences with the technology.

scholarly journals Distribution and impact of the alien anemone Sagartia ornata in the West Coast National Park

Koedoe ◽  
2015 ◽  
Vol 57 (1) ◽  
Author(s):  
Tamara B. Robinson ◽  
Cheruscha Swart
Keyword(s):  
West Coast ◽  
National Park ◽  
Diet Analysis ◽  
Current Status ◽  
Rocky Shores ◽  
The West ◽  
Sandy Shore ◽  
Conservation Implications ◽  
Invertebrate Diversity ◽  
Density And Biomass

Sagartia ornata is an alien anemone that occurs intertidally within the West Coast National Park (WCNP). Whilst baseline distributional data was gathered in 2001, the range and abundance of this alien has not been reassessed. The present study aimed to determine the current status and distribution of this anemone, to assess its diet so as to establish the role it may play as predator and to investigate its impact on sandy-shore communities. Sagartia ornata was found to be restricted to the WCNP, where it occurred in densities of up to 508 ± 218 individuals per m2 . Within the park the distribution of this anemone had changed. Populations were recorded in Nanozostera capensis seagrass beds for the first time and this alien was absent from two areas in which it had previously occurred. Diet analysis revealed indigenous polychaetes and amphipods as the dominant prey items consumed by S. ornata. This alien was found to significantly alter sandy-shore community structure, with differences caused primarily by increases in the abundance and biomass of the tanaid Anatanais gracilis and the polychaete Orbinia angrapequensis. Additionally, invaded areas supported significantly greater invertebrate diversity, density and biomass. It is concluded that whilst this anemone negatively affects native biota, its current dependence on restricted habitats precludes widespread impacts with the park.Conservation implications: With regard to conservation implications, this invasion should be routinely monitored outside the WCNP as in its native range S. ornata occurs on rocky shores and kelp holdfasts, suggesting a potential for spread along the west coast of South Africa.

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