2 Wildebeest in the Serengeti: Limits to Exponential Growth
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Serengeti National Park
Serengeti • National Park A Guide Published by Tanzania National Parks Illustrated by Eliot Noyes ~~J /?ookH<~t:t;~ 2:J . /1.). lf31 SERENGETI NATIONAL PARK A Guide to your increased enjoyment As the Serengeti National Park is nearly as big as Kuwait or Northern Ireland no-one, in a single visit, can hope to see Introduction more than a small part of it. If time is limited a trip round The Serengeti National Park covers a very large area : the Seronera valley, with opportunities to see lion and leopard, 13,000 square kilometres of country stretching from the edge is probably the most enjoyable. of the Ngorongoro Conservation Unit in the south to the Kenya border in the north, and from the shores of Lake Victoria in the If more time is available journeys can be made farther afield, west to the Loliondo Game Controlled Area in the east. depending upon the season of the year and the whereabouts of The name "Serengeti" is derived from the Maasai language the wildlife. but has undergone various changes. In Maasai the name would be "Siringet" meaning "an extended area" but English has Visitors are welcome to get out of their cars in open areas, but replaced the i's with e's and Swahili has added a final i. should not do so near thick cover, as potentially dangerous For all its size, the Serengeti is not, of itself, a complete animals may be nearby. ecological unit, despite efforts of conservationists to make it so. Much of the wildlife· which inhabits the area moves freely across Please remember that travelling in the Park between the hours the Park boundaries at certain seasons of the year in search of 7 p.m. -
Modeling Techniques
Appendix A Modeling Techniques A.1 Population Growth Models Using Differential Equations Our main goal here is to introduce a few modeling techniques we use throughout this book. We do not intend however to provide here the fundamentals on modeling, a tutorial or a review. For these, we refer to other sources (DeAngelis et al. 1992; Ford 2009; Grimm et al. 2006; Kuang 1993). This Appendix is rather a refresher as well as an example of why using different modeling techniques for one and the same problem can be beneficial to understand biological processes better. We start with the simple exponential population growth to make modeling accessible even to complete beginners. Biologists generally define a population as a collection of individuals that belong to the same species and can potentially breed with each other. One of the best-known early models on population growth was outlined by Malthus (1798). He famously maintained that the human population is predicted to grow in an exponential manner, but the crucial products needed to sustain the population grow in but a linear manner. He argued that these different types of growths will trigger disasters when the population’s needs are not satisfied. The basic exponential growth model consists of a single positive feedback loop that arises from the fact that every individual (N) is predicted to have a fixed number of offspring (r), regardless of the size of the population, and thus also regardless of the remaining resources in the habitat: dN = rN dt (A.1.1) This exponential growth model had a profound effect on biology such as developing the theory of natural selection (Darwin 1859). -
Serengeti: Nature's Living Laboratory Transcript
Serengeti: Nature’s Living Laboratory Transcript Short Film [crickets] [footsteps] [cymbal plays] [chime] [music plays] [TONY SINCLAIR:] I arrived as an undergraduate. This was the beginning of July of 1965. I got a lift down from Nairobi with the chief park warden. Next day, one of the drivers picked me up and took me out on a 3-day trip around the Serengeti to measure the rain gauges. And in that 3 days, I got to see the whole park, and I was blown away. [music plays] I of course grew up in East Africa, so I’d seen various parks, but there was nothing that came anywhere close to this place. Serengeti, I think, epitomizes Africa because it has everything, but grander, but louder, but smellier. [music plays] It’s just more of everything. [music plays] What struck me most was not just the huge numbers of antelopes, and the wildebeest in particular, but the diversity of habitats, from plains to mountains, forests and the hills, the rivers, and all the other species. The booming of the lions in the distance, the moaning of the hyenas. Why was the Serengeti the way it was? I realized I was going to spend the rest of my life looking at that. [NARRATOR:] Little did he know, but Tony had arrived in the Serengeti during a period of dramatic change. The transformation it would soon undergo would make this wilderness a living laboratory for understanding not only the Serengeti, but how ecosystems operate across the planet. This is the story of how the Serengeti showed us how nature works. -
Influence of Common Eland (Taurotragus Oryx) Meat Composition on Its Further Technological Processing
CZECH UNIVERSITY OF LIFE SCIENCES PRAGUE Faculty of Tropical AgriSciences Department of Animal Science and Food Processing Influence of Common Eland (Taurotragus oryx) Meat Composition on its further Technological Processing DISSERTATION THESIS Prague 2018 Author: Supervisor: Ing. et Ing. Petr Kolbábek prof. MVDr. Daniela Lukešová, CSc. Co-supervisors: Ing. Radim Kotrba, Ph.D. Ing. Ludmila Prokůpková, Ph.D. Declaration I hereby declare that I have done this thesis entitled “Influence of Common Eland (Taurotragus oryx) Meat Composition on its further Technological Processing” independently, all texts in this thesis are original, and all the sources have been quoted and acknowledged by means of complete references and according to Citation rules of the FTA. In Prague 5th October 2018 ………..………………… Acknowledgements I would like to express my deep gratitude to prof. MVDr. Daniela Lukešová CSc., Ing. Radim Kotrba, Ph.D. and Ing. Ludmila Prokůpková, Ph.D., and doc. Ing. Lenka Kouřimská, Ph.D., my research supervisors, for their patient guidance, enthusiastic encouragement and useful critiques of this research work. I am very gratefull to Ing. Petra Maxová and Ing. Eva Kůtová for their valuable help during the research. I am also gratefull to Mr. Petr Beluš, who works as a keeper of elands in Lány, Mrs. Blanka Dvořáková, technician in the laboratory of meat science. My deep acknowledgement belongs to Ing. Radek Stibor and Mr. Josef Hora, skilled butchers from the slaughterhouse in Prague – Uhříněves and to JUDr. Pavel Jirkovský, expert marksman, who shot the animals. I am very gratefull to the experts from the Natura Food Additives, joint-stock company and from the Alimpex-maso, Inc. -
Density Dependence in Demography and Dispersal Generates Fluctuating
Density dependence in demography and dispersal generates fluctuating invasion speeds Lauren L. Sullivana,1, Bingtuan Lib, Tom E. X. Millerc, Michael G. Neubertd, and Allison K. Shawa aDepartment of Ecology, Evolution and Behavior, University of Minnesota, Saint Paul, MN 55108; bDepartment of Mathematics, University of Louisville, Louisville, KY 40292; cDepartment of BioSciences, Program in Ecology and Evolutionary Biology, Rice University, Houston, TX 77005; and dBiology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543 Edited by Alan Hastings, University of California, Davis, CA, and approved March 30, 2017 (received for review November 23, 2016) Density dependence plays an important role in population regu- is driven by reproduction and dispersal from high-density pop- lation and is known to generate temporal fluctuations in popu- ulations behind the invasion front (13–15)]. The conventional lation density. However, the ways in which density dependence wisdom of a long-term constant invasion speed is widely applied affects spatial population processes, such as species invasions, (16, 17). are less understood. Although classical ecological theory suggests In contrast to classic approaches that emphasize a long-term that invasions should advance at a constant speed, empirical work constant speed, there is growing empirical recognition that inva- is illuminating the highly variable nature of biological invasions, sion dynamics can be highly variable and idiosyncratic (18–25). which often exhibit nonconstant spreading speeds, even in sim- There are several theoretical explanations for fluctuations in ple, controlled settings. Here, we explore endogenous density invasion speed (which we define here as any persistent tem- dependence as a mechanism for inducing variability in biologi- poral variability in spreading speed), including stochasticity in cal invasions with a set of population models that incorporate either demography or dispersal (24–28) and temporal or spatial density dependence in demographic and dispersal parameters. -
Sustainable Use of Wildland Resources: Ecological, Economic and Social Interactions
Sustainable Use of Wildland Resources: Ecological, Economic and Social Interactions An Analysis of Illegal Hunting of Wildlife in Serengeti National Park, Tanzania Ken Campbell, Valerie Nelson and Martin Loibooki June 2001 Main Report This report should be cited as: Campbell, K. L. I., Nelson, V. and Loibooki, M. (2001). Sustainable use of wildland resources, ecological, economic and social interactions: An analysis of illegal hunting of wildlife in Serengeti National Park, Tanzania. Department for International Development (DFID) Animal Health Programme and Livestock Production Programmes, Final Technical Report, Project R7050. Natural Resources Institute (NRI), Chatham, Kent, UK. 56 pp. 2 Sustainable Use of Wildland Resources: Ecological, Economic and Social Interactions An Analysis of Illegal Hunting of wildlife in Serengeti National Park, Tanzania FINAL TECHNICAL REPORT, 2001 DFID Animal Health and Livestock Production Programmes, Project R7050 Ken Campbell1, Valerie Nelson2 Natural Resources Institute, University of Greenwich, Chatham, ME4 4TB, UK and Martin Loibooki Tanzania National Parks, P.O. Box 3134, Arusha, Tanzania Executive Summary A common problem for protected area managers is illegal or unsustainable extraction of natural resources. Similarly, lack of access to an often decreasing resource base may also be a problem for rural communities living adjacent to protected areas. In Tanzania, illegal hunting of both resident and migratory wildlife is a significant problem for the management of Serengeti National Park. Poaching has already reduced populations of resident wildlife, whilst over-harvesting of the migratory herbivores may ultimately threaten the integrity of the Serengeti ecosystem. Reduced wildlife populations may in turn undermine local livelihoods that depend partly on this resource. This project examined illegal hunting from the twin perspectives of conservation and the livelihoods of people surrounding the protected area. -
Plant Diversity Increases with the Strength of Negative Density Dependence at the Global Scale
RESEARCH FOREST ECOLOGY predators, pathogens, or herbivores) and/or com- petition for space and resources (2–4, 7). Numer- ous studies have documented the existence of CNDD in one or several plant species (8–12), and Plant diversity increases with the most of these studies explicitly or implicitly as- sume that stronger CNDD maintains higher spe- strength of negative density cies diversity in communities. However, only a handful of studies have explicitly examined dependence at the global scale the link between CNDD and species diversity (4, 11, 13, 14),andnostudyhasexaminedthis relationship across temperate and tropical lat- Joseph A. LaManna,1,2* Scott A. Mangan,2 Alfonso Alonso,3 Norman A. Bourg,4,5 itudes. Despite decades of study, our understand- Warren Y. Brockelman,6,7 Sarayudh Bunyavejchewin,8 Li-Wan Chang,9 ing of how processes at local scales—such as Jyh-Min Chiang,10 George B. Chuyong,11 Keith Clay,12 Richard Condit,13 density-dependent biotic interactions—influence Susan Cordell,14 Stuart J. Davies,15,16 Tucker J. Furniss,17 Christian P. Giardina,14 18 18 19,20 global patterns of biodiversity remains in flux I. A. U. Nimal Gunatilleke, C. V. Savitri Gunatilleke, Fangliang He, 1 15 21 22 23 ( , ). Robert W. Howe, Stephen P. Hubbell, Chang-Fu Hsieh, Both species-specific and more generalized 14 24 25 15,16 Faith M. Inman-Narahari, David Janík, Daniel J. Johnson, David Kenfack, mechanisms can cause CNDD, but only CNDD 3 24 26 17 Lisa Korte, Kamil Král, Andrew J. Larson, James A. Lutz, caused by species-specific mechanisms can main- 27,28 4 29 Sean M. -
"Density Dependence and Independence"
Density Dependence and Advanced article Independence Article Contents . Introduction: Concepts and Importance in Ecology Mark A Hixon, Oregon State University, Corvallis, Oregon, USA . Mechanisms of Density Dependence . Old Debates Resolved Darren W Johnson, Oregon State University, Corvallis, Oregon, USA . Detecting Density Dependence . Future Directions Online posting date: 15th December 2009 Density dependence occurs when the population growth parameter of interest involves population dynamics, rate, or constituent gain rates (e.g. birth and immi- including the population growth rate and the four primary gration) or loss rates (death and emigration), vary caus- demographic (or vital) rates – birth, death, immigration ally with population size or density (N). When these and emigration – although related parameters, such as growth and fecundity, are also investigated. See also: parameters do not vary with N, they are density-inde- Population Dynamics: Introduction pendent. Direct density dependence, where the popu- Use of the words ‘density dependence’ alone normally lation growth rate or gain rates vary as a negative means ‘direct density dependence’ (or compensation): the function of N, or the loss rates vary as a positive function of per capita (proportional) gain rate (population or indi- N, is necessary but not always sufficient for population vidual growth, fecundity, birth or immigration) decreases regulation. The opposite patterns, inverse density as N increases (Figure 1a) or the loss rate (death and/or dependence or the Allee effect, may push endangered emigration) increases as N increases (Figure 1b). The populations towards extinction. Direct density depend- opposite patterns are called inverse density dependence (or ence is caused by competition, and at times, predation. -
Serengeti National Park Tanzania
SERENGETI NATIONAL PARK TANZANIA Twice a year ungulate herds of unrivalled size pour across the immense savanna plains of Serengeti on their annual migrations between grazing grounds. The river of wildebeests, zebras and gazelles, closely followed by predators are a sight from another age: one of the most impressive in the world. COUNTRY Tanzania NAME Serengeti National Park NATURAL WORLD HERITAGE SITE 1981: Inscribed on the World Heritage List under Natural Criteria vii and x. STATEMENT OF OUTSTANDING UNIVERSAL VALUE [pending] INTERNATIONAL DESIGNATION 1981: Serengeti-Ngorongoro recognised as a Biosphere Reserve under the UNESCO Man & Biosphere Programme (2,305,100 ha, 1,476,300 ha being in Serengeti National Park). IUCN MANAGEMENT CATEGORY II National Park BIOGEOGRAPHICAL PROVINCE East African Woodland/Savanna (3.05.04) GEOGRAPHICAL LOCATION In the far north of Tanzania 200 km west of Arusha, adjoining the Ngorongoro Conservation Area, between 1° 30' to 3° 20'S and 34° 00' to 35°15'E. DATES AND HISTORY OF ESTABLISHMENT 1929: Serengeti Game Reserve declared (228,600 ha) to preserve lions, previously seen as vermin; 1940: Declared a Protected Area; 1951: Serengeti National Park created, including Ngorongoro; boundaries were modified in 1959; 1981: Recognised as part of the Serengeti-Ngorongoro UNESCO Biosphere Reserve. LAND TENURE State, in Mara, Arusha and Shinyanga provinces. Administered by the Tanzanian National Parks Authority. AREA 1,476,300ha. It is contiguous in the southeast with Ngorongoro Conservation Area (809,440ha), in the southwest with Maswa Game Reserve (220,000ha), in the west with the Ikorongo-Grumeti Game Reserves (500,000ha), in the north with the Maasai-Mara National Reserve (151,000ha) in Kenya and in the northeast with the Loliondo Game Controlled Area (400,000ha). -
Connochaetes Gnou – Black Wildebeest
Connochaetes gnou – Black Wildebeest Blue Wildebeest (C. taurinus) (Grobler et al. 2005 and ongoing work at the University of the Free State and the National Zoological Gardens), which is most likely due to the historic bottlenecks experienced by C. gnou in the late 1800s. The evolution of a distinct southern endemic Black Wildebeest in the Pleistocene was associated with, and possibly driven by, a shift towards a more specialised kind of territorial breeding behaviour, which can only function in open habitat. Thus, the evolution of the Black Wildebeest was directly associated with the emergence of Highveld-type open grasslands in the central interior of South Africa (Ackermann et al. 2010). Andre Botha Assessment Rationale Regional Red List status (2016) Least Concern*† This is an endemic species occurring in open grasslands in the central interior of the assessment region. There are National Red List status (2004) Least Concern at least an estimated 16,260 individuals (counts Reasons for change No change conducted between 2012 and 2015) on protected areas across the Free State, Gauteng, North West, Northern Global Red List status (2008) Least Concern Cape, Eastern Cape, Mpumalanga and KwaZulu-Natal TOPS listing (NEMBA) (2007) Protected (KZN) provinces (mostly within the natural distribution range). This yields a total mature population size of 9,765– CITES listing None 11,382 (using a 60–70% mature population structure). This Endemic Yes is an underestimate as there are many more subpopulations on wildlife ranches for which comprehensive data are *Watch-list Threat †Conservation Dependent unavailable. Most subpopulations in protected areas are stable or increasing. -
Literature Cited in Lizards Natural History Database
Literature Cited in Lizards Natural History database Abdala, C. S., A. S. Quinteros, and R. E. Espinoza. 2008. Two new species of Liolaemus (Iguania: Liolaemidae) from the puna of northwestern Argentina. Herpetologica 64:458-471. Abdala, C. S., D. Baldo, R. A. Juárez, and R. E. Espinoza. 2016. The first parthenogenetic pleurodont Iguanian: a new all-female Liolaemus (Squamata: Liolaemidae) from western Argentina. Copeia 104:487-497. Abdala, C. S., J. C. Acosta, M. R. Cabrera, H. J. Villaviciencio, and J. Marinero. 2009. A new Andean Liolaemus of the L. montanus series (Squamata: Iguania: Liolaemidae) from western Argentina. South American Journal of Herpetology 4:91-102. Abdala, C. S., J. L. Acosta, J. C. Acosta, B. B. Alvarez, F. Arias, L. J. Avila, . S. M. Zalba. 2012. Categorización del estado de conservación de las lagartijas y anfisbenas de la República Argentina. Cuadernos de Herpetologia 26 (Suppl. 1):215-248. Abell, A. J. 1999. Male-female spacing patterns in the lizard, Sceloporus virgatus. Amphibia-Reptilia 20:185-194. Abts, M. L. 1987. Environment and variation in life history traits of the Chuckwalla, Sauromalus obesus. Ecological Monographs 57:215-232. Achaval, F., and A. Olmos. 2003. Anfibios y reptiles del Uruguay. Montevideo, Uruguay: Facultad de Ciencias. Achaval, F., and A. Olmos. 2007. Anfibio y reptiles del Uruguay, 3rd edn. Montevideo, Uruguay: Serie Fauna 1. Ackermann, T. 2006. Schreibers Glatkopfleguan Leiocephalus schreibersii. Munich, Germany: Natur und Tier. Ackley, J. W., P. J. Muelleman, R. E. Carter, R. W. Henderson, and R. Powell. 2009. A rapid assessment of herpetofaunal diversity in variously altered habitats on Dominica. -
IUCN Briefing Paper
BRIEFING PAPER September 2016 Contact information updated April 2019 Informing decisions on trophy hunting A Briefing Paper regarding issues to be taken into account when considering restriction of imports of hunting trophies For more information: SUMMARY Dilys Roe Trophy hunting is currently the subject of intense debate, with moves IUCN CEESP/SSC Sustainable Use at various levels to end or restrict it, including through increased bans and Livelihoods or restrictions on carriage or import of trophies. This paper seeks to inform SpecialistGroup these discussions. [email protected] Patricia Cremona IUCN Global Species (such as large antlers), and overlaps with widely practiced hunting for meat. Programme It is clear that there have been, and continue to be, cases of poorly conducted [email protected] and poorly regulated hunting. While “Cecil the Lion” is perhaps the most highly publicised controversial case, there are examples of weak governance, corruption, lack of transparency, excessive quotas, illegal hunting, poor monitoring and other problems in a number of countries. This poor practice requires urgent action and reform. However, legal, well regulated trophy Habitat loss and degradation is a primary hunting programmes can, and do, play driver of declines in populations an important role in delivering benefits of terrestrial species. Demographic change for both wildlife conservation and for and corresponding demands for land for the livelihoods and wellbeing of indigenous development are increasing in biodiversity- and local communities living with wildlife. rich parts of the globe, exacerbating this pressure on wildlife and making the need for viable conservation incentives more urgent. © James Warwick RECOMMENDATIONS and the rights and livelihoods of indigenous and local communities, IUCN calls on relevant decision- makers at all levels to ensure that any decisions that could restrict or end trophy hunting programmes: i.