Relationships between reproduction and environment in the Hippopotamus <i>Hippopotamus Amphibius</i> in the Kruger National Park

Hippopotamus Hippopotamus amphibius reproduction in the Kruger National Park, Republic of South Africa, is described and compared with that of other populations in Africa and with captive reared specimens. Information collected during drought and pluvial periods indicates that adult hippo cows react to adverse environmental conditions (reduced shelter in pools, overcrowding and food scarcity) by marked declines in conception rates (from 36,7 @ 5,6). Indirect evidence indicates that when environmental conditions are unfavourable calf survival is improved by extending the period of lactation and by calves suckling more than one cow. During favourable years some calves mature early (S S, 2 years, and 9 9 5 years) but generally sexual maturity is attained at six and 9-10 years for males and females respectively. The calving interval, when environmental conditions are favourable, is about two years and reproductive senescence and sterility are insignificant factors. The population sex ratio is 1:1. Hippos appear to be typical K-selected species. Environmental constraints have caused them to adopt a low reproductive rate and high survival rate and consequently a close adjustment to the long-term carrying capacity of the environment.

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Long‐term population studies and the development of an integrated management programme for control of Opuntia stricta in Kruger National Park, South Africa

Journal of Applied Ecology ◽

10.1046/j.1365-2664.1998.00283.x ◽

1998 ◽

Vol 35 (1) ◽

pp. 156-160 ◽

Cited By ~ 42

Author(s):

J.H. Hoffmann ◽

V.C. Moran ◽

D.A. Zeller

Keyword(s):

South Africa ◽

National Park ◽

Population Studies ◽

Integrated Management ◽

Management Programme ◽

Kruger National Park

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Population abundance of the common hippopotamus Hippopotamus amphibius in the Haut Niger National Park, Republic of Guinea / Abondance de la population d'hippopotame commun Hippopotamus amphibius dans le Parc National du Haut Niger, République de Guinée

Mammalia ◽

10.1515/mamm.70.1-2.14 ◽

2006 ◽

Vol 70 (1-2) ◽

Author(s):

David Brugière ◽

Bakary Magassouba ◽

Amidou Sylla ◽

Halimou Diallo ◽

Mamadou Sow

Keyword(s):

National Park ◽

Buffer Zone ◽

Wet Season ◽

Republic Of Guinea ◽

Hippopotamus Amphibius ◽

The Status ◽

Grazing Area ◽

The Common ◽

The Republic

AbstractThe Republic of Guinea is thought to contain the largest population of common hippopotamus in West Africa. However, no systematic field survey has been carried out recently and the information available is limited to informal observations. To clarify the status of the common hippopotamus in Guinea, we carried out a biannual population survey along the section of the Niger River (the largest river in Guinea) within the Haut Niger National Park. We counted 93 hippopotamuses in 28 groups in the dry season and 77 hippopotamuses in 23 groups in the wet season. Mean group size and number of neonates did not change between the seasons. Hippopotomuses were more numerous along the river sections bordering uncultivated floodplains. This underlines the significance of this habitat (which is used as a grazing area) for conservation of this species. Haut Niger National Park is the most important protected area in Guinea for conservation of the common hippopotamus. Hippopotamus-human and -cattle conflicts in terms of floodplain use in the park's buffer zone should be closely monitored. Floodplain conversion to rice fields represents one of the most important threats to the long-term conservation of hippopotamus populations in Guinea.

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The dynamics of questing ticks collected for 164 consecutive months off the vegetation of two landscape zones in the Kruger National Park (1988–2002). Part II. Rhipicephalus appendiculatus and Rhipicephalus zambeziensis

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v78i1.233 ◽

2011 ◽

Vol 78 (1) ◽

Cited By ~ 9

Author(s):

Arthur M. Spickett ◽

Gordon J. Gallivan ◽

Ivan G. Horak

Keyword(s):

Population Dynamics ◽

Relative Humidity ◽

National Park ◽

Rhipicephalus Appendiculatus ◽

Kruger National Park ◽

Large Herbivore ◽

Questing Ticks ◽

Over Time

The study aimed to assess the long-term population dynamics of questing Rhipicephalus appendiculatus and Rhipicephalus zambeziensis in two landscape zones of the Kruger National Park (KNP). Ticks were collected by dragging the vegetation monthly in three habitats (grassland, woodland and gully) at two sites in the KNP (Nhlowa Road and Skukuza) from August 1988 to March 2002. Larvae were the most commonly collected stage of both species. More R. appendiculatus were collected at Nhlowa Road than at Skukuza, with larvae being most abundant from May to August, while nymphs were most abundant from August to December. Larvae were most commonly collected in the gullies from 1991 to 1994, but in the grassland and woodland habitats from 1998 onwards. Nymphs were most commonly collected in the grassland and woodland. More R. zambeziensis were collected at Skukuza than at Nhlowa Road, with larvae being most abundant from May to September, while nymphs were most abundant from August to November. Larvae and nymphs were most commonly collected in the woodland and gullies and least commonly in the grassland (p < 0.01). The lowest numbers of R. appendiculatus were collected in the mid-1990s after the 1991/1992 drought. Rhipicephalus zambeziensis numbers declined after 1991 and even further after 1998, dropping to their lowest levels during 2002. The changes in numbers of these two species reflected changes in rainfall and the populations of several of their large herbivore hosts, as well as differences in the relative humidity between the two sites over time.

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Changes in number and distribution of hippoptamus (Hippopotamus amphibius) in the Sabie River, Kruger National Park, during the 1992 drought

Koedoe ◽

10.4102/koedoe.v38i2.320 ◽

1995 ◽

Vol 38 (2) ◽

Cited By ~ 6

Author(s):

P.C. Viljoen

Keyword(s):

Southern Africa ◽

National Park ◽

Dry Season ◽

Kruger National Park ◽

Population Densities ◽

Drought Period ◽

Aerial Surveys ◽

Hippopotamus Amphibius ◽

Reduced Flow

The 1991/92 drought in Southern Africa and the effect of the resultant reduced flow of the Sabie River on hippopotami was investigated. Hippopotami are counted annually in the Kruger National Park's (KNP) major rivers as part of the park's monitoring pro- gramme. Two additional aerial surveys were conducted to document changes in hippopotamus population densities in the Sabie River during the drought period. The hippopotamus population decreased during the drought by 12.6 to 672 animals between July 1991 and October 1992. The highest and lowest hippopotamus densities recorded were 11.6 and 2.2 animals/km river length respectively in different river sections. Only 12 hippopotamus mortalities were recorded at the end of the 1992 dry season (October).

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The dynamics of questing ticks collected for 164 consecutive months off the vegetation of two landscape zones in the Kruger National Park (1988–2002). Part III. The less commonly collected species

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v78i1.41 ◽

2011 ◽

Vol 78 (1) ◽

Cited By ~ 14

Author(s):

Gordon J. Gallivan ◽

Andrea Spickett ◽

Heloise Heyne ◽

Arthur M. Spickett ◽

Ivan G. Horak

Keyword(s):

National Park ◽

Development Stage ◽

Kruger National Park ◽

Ixodid Ticks ◽

Limited Information ◽

Host Seeking ◽

Haemaphysalis Elliptica ◽

Questing Ticks ◽

Landscape Zone

Despite many studies regarding tick ecology, limited information on long-term changes in tick populations exist. This study assessed the long-term population dynamics of the less frequently collected questing ixodid ticks in the Kruger National Park (KNP). From 1988 to 2002, monthly dragging of the vegetation was performed in three habitats (grassland, woodland and gully) at two sites in the KNP (Nhlowa Road, Landscape Zone 17, and Skukuza, Landscape Zone 4). Amblyomma marmoreum and Rhipicephalus evertsi evertsi were collected as larvae most commonly. Most A. marmoreum larvae were collected at Skukuza and numbers peaked from March to July. More R. evertsi evertsi larvae were collected at Nhlowa Road and numbers peaked in summer and in winter, while at Skukuza there was a single peak in spring. Haemaphysalis elliptica, Rhipicephalus simus and Rhipicephalus turanicus were collected as adults most commonly. More Ha. elliptica and R. turanicus were collected at Nhlowa Road than at Skukuza, while R. simus numbers from the two sites were approximately equal. Ha. elliptica were collected most often between February and June, and R. simus and R. turanicus during February and March. All three species were collected more frequently in gullies than in grassland or woodland. Their numbers increased in 1994/1995 following an eruption of rodents, the preferred hosts of the immature stages. The different host-seeking strategies of ticks largely determine the development stage at which they are likely to be collected during vegetation dragging and reflect a complex interaction between ticks, their hosts and the environment.

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Tetanus in a free-living Hippopotamus Hippopotamus Amphibius Capensis from the Kruger National Park

Koedoe ◽

10.4102/koedoe.v23i1.644 ◽

1980 ◽

Vol 23 (1) ◽

Cited By ~ 1

Author(s):

V De Vos ◽

B. D De Klerk

Keyword(s):

National Park ◽

Kruger National Park ◽

Polluted Water ◽

Intraspecific Aggression ◽

Way Of Life ◽

Free Living ◽

Clostridium Tetani ◽

Ample Opportunity ◽

Close Proximity ◽

Hippopotamus Amphibius

Tetanus in a free-living hippopotamus (Hippopotamus amphibius) from the Kruger National Park is described. The animal exhibited the classical tetanus symptomatology, the most salient clinical features being trauma (skin wounds) associated with exaggerated response of voluntary muscles to trivial stimuli, muscular spasms, general muscular rigidity, trismus, prolapsed third eye-lid and the preservation of consciousness. It is conjectured that the hippo's semi-aquatic way of life with its close proximity to dung-polluted water and an innate intraspecific aggression amongst males which often leads to fighting and trauma, should provide ample opportunity for infection with Clostridium tetani.

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The contribution of fire research to fire management: a critical review of a long-term experiment in the Kruger National Park, South Africa

International Journal of Wildland Fire ◽

10.1071/wf06115 ◽

2007 ◽

Vol 16 (5) ◽

pp. 519 ◽

Cited By ~ 61

Author(s):

Brian W. van Wilgen ◽

Navashni Govender ◽

Harry C. Biggs

Keyword(s):

South Africa ◽

National Park ◽

Fire Management ◽

Basic Research ◽

Kruger National Park ◽

Management Policy ◽

Wet Season ◽

Long Term Experiment ◽

Faunal Communities

The present paper reviews a long-term fire experiment in the Kruger National Park, South Africa, established in 1954 to support fire management. The paper’s goals are: (1) to assess learning, with a focus on relevance for fire management; (2) to examine how findings influenced changes in fire management; and (3) to reflect on the experiment’s future. Results show that fire treatments affected vegetation structure and biomass more than species composition. Effects on vegetation were most marked in extreme treatments (annual burning, burning in the summer wet season, or long periods of fire exclusion), and were greater in areas of higher rainfall. Faunal communities and soil physiology were largely unaffected by fire. Since the inception of the experiment, paradigms in savanna ecology have changed to encompass heterogeneity and variability. The design of the experiment, reflecting the understanding of the 1950s, does not cater for variability, and as a result, the experiment had little direct influence on changes in management policy. Notwithstanding this, managers accept that basic research influences the understanding of fundamental ecosystem function, and they recognise that it promotes appropriate adaptive management by contributing to predictive understanding. This has been a major reason for maintaining the experiment for over 50 years.

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Seven decades of institutional learning: managing alien plant invasions in the Kruger National Park, South Africa

Oryx ◽

10.1017/s0030605307001871 ◽

2007 ◽

Vol 41 (2) ◽

pp. 160-167 ◽

Cited By ~ 23

Author(s):

Llewellyn C. Foxcroft ◽

Stefanie Freitag-Ronaldson

Keyword(s):

South Africa ◽

National Park ◽

Invasive Plant ◽

Current Control ◽

Kruger National Park ◽

Plant Management ◽

Plant Interactions ◽

Alien Plant ◽

Invasive Plant Management

AbstractLong-term ecological and economic sustainability will ultimately determine the outcome of any conservation management programme. Invasive alien plants, first recorded in the Kruger National Park, South Africa, in 1937, are now recognized as one of the greatest threats to the biodiversity of this Park. Such plants have been managed in the Park since 1956, with control advancing mainly through a process of trial and error. Refinement of invasive plant management strategies has resulted in an understanding of the target plants' biology and ecology, herbicide use and herbicide-plant interactions, as well as the plant-insect interactions of biological control. Careful integration of different control methods has proved essential to ensure the most appropriate use of techniques to deliver the best possible results from the resources available and achieve long-term sustainability. We outline the development of control efforts and current control programmes and the process of their incorporation into the institutional memory of Kruger National Park over the last 7 decades.

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