Herd Movements Research Articles

Sudden Shift or Migratory Drift? FulBe Herd Movements to the Sudano-Guinean Region of West Africa

A significant change in the geography of livestock raising over the past 30 years is the southerly movement of FulBe herds into the humid Sudanian and Guinean savannas of West Africa. The literature suggests that the severe droughts of the early 1970s and mid-1980s were the driving force behind this southern expansion of mobile livestock raising. The conventional view is that drought forced herders to seek greener pastures to the south, an area that zebu cattle have previously avoided because of the presence of tsetse flies, the vector of animal sleeping sickness (trypanosomiasis). This “sudden push” hypothesis places Sahelian herds in savanna pastures in a matter of a 1–3 years. This stimulus-response model runs counter to our observations and understanding of the social and ecological processes influencing FulBe herd movements. We challenge the “sudden shift” thesis at the regional scale by arguing that the southerly expansion of FulBe herds has proceeded according to a more complex temporal frame that includes generational, biological, and social historical timeframes and periodicities. We distinguish between short-term shifts (“test movements”) and more permanent shifts (“migration movements”). These mobility patterns are linked to contingent factors such as cattle diseases, drought, and political instability, as well as to more structural and adaptive features such as the establishment of social networks, herding contracts, and cattle cross-breeding. Shifts in livestock ownership and the social differentiation among herders are important variables for understanding changes in herd movements. We conclude that the permanent shift of herds to the humid savannas of West Africa has been preceded by a series of social and agroecological adjustments that operate on decadal and generational time scales.

Rift Valley fever in West Africa: the role of space in endemicity

Rift Valley fever is an endemic vector-borne disease in West Africa, which mainly affects domestic ruminants and occasionally humans. The aetiological mechanisms of its endemicity remain under debate. We used a simple spatially explicit model to assess the possibility of endemicity without wild animals providing a permanent virus reservoir. Our model takes into account the vertical transmission in some mosquito species, the rainfall-driven emergence of their eggs and local and distant contacts because of herd migration. Endemicity without such a permanent virus reservoir would be impossible in a single site except when there is a strictly periodic rainfall pattern; but it would be possible when there are herd movements and sufficient inter-site variability in rainfall, which drives mosquito emergence.

Response of dugongs to boat traffic: The risk of disturbance and displacement

Disturbance from boats has been documented for many species of marine mammals, especially cetaceans, but has never been quantified for dugongs. Dugongs depend on seagrass for food. This food mostly occurs in shallow coastal areas where boat traffic is high. Thus there is potential for boats to alienate dugongs from critical habitat areas. Using an overhead video observation system (‘blimp-cam’), we observed the behaviour of focal dugongs during controlled boat pass experiments and while no boats were present. The percentage of time focal dugongs spent feeding and travelling was unaffected by boat presence, the number of boat passes and whether a pass included a stop and restart (pass continuity). The duration, distance and direction of a focal dugong's subsurface behaviour were unaffected by number, continuity or distance of boat passes. However, focal dugongs were less likely to continue feeding if the boat passed within 50 m, than if the boat passed at a greater distance. Mass movements of dugong feeding herds in response to experimental and opportunistically observed boats were timed on 42 occasions but only lasted an average of 122 s. These movements occurred in response to boats passing at a range of speeds, and at distances of less than 50 m to over 500 m. The levels of boat traffic we observed may reduce dugongs' feeding time budget by a maximum of 0.8–6%. Thus at present boats appear unlikely to be having a substantive effect on the energy intake of dugong populations at our study site on the Moreton Banks near Brisbane, Australia. However, boat traffic is likely to increase in this fast growing region, raising concern about the future impact of boats on this and other dugong populations.

Managing Variability: Herding Strategies in Communal Rangelands of Semiarid Namaqualand, South Africa

Herd mobility is a tool for managing environmental variability in African pastoral systems. This study examines the monthly mobility patterns of 24 herds over six years in the 20,000 ha communal area of Paulshoek, Namaqualand, and assesses the social, economic, and ecological factors affecting the livestock movement of individual herds and all herds combined. When the mobility pattern of all herds was considered, no seasonal or between-year differences in response to rainfall were evident. An analysis of individual herd mobility patterns showed that half of the herds were relatively sedentary over the study period while the other half were regularly mobile. Although herders used mobility to manage their herds in the unpredictable semiarid environment, their daily decisions were often made in response to their social, economic, or personal situations. There was no significant difference in livestock production between herding strategies, but sedentary herders had a greater localized impact on the rangeland than mobile herders. Our analysis suggests that non-environmental factors play a significant role in herd mobility and may consequently affect the efficiency of livestock production and environmental management.

Live Nativity and Brucellosis, Sicily

To the Editor: Worldwide, brucellosis remains a major zoonosis and an important cause of travel-associated illness (1). Brucellosis is transmitted to humans through the consumption of infected, unpasteurized, animal-milk products; direct contact with infected animal parts; or inhalation of infected aerosolized particles. We report an outbreak of brucellosis in a small village of the Ionic coast of Messina province (eastern Sicily). In 2003, health authorities in the Messina province were notified of 29 cases of brucellosis; 18 of the patients were members of 9 different families. All patients had observed a Nativity pantomime that used live animals and was organized by the local population. Nativities in Sicily last ≈1 month, during which the sheep are milked, cheese and are produced, and these products are sold or offered fresh to tourists. All 29 patients had consumed dairy products: tuma cheese by 29 (100%) and tuma and by 16 (55%). No other risk factors for brucellosis were reported. Symptoms appeared after a median of 45 days (range 30–70). Eight patients were children (3 male), and 21 were adults (10 male). The median age of the children was 10.5 years (range 6–13) and of the adults, 42 years (range 16–67). Hospitalization was required for 5 patients. For 2 adults, brucellosis was complicated by spondylitis. The real extent of the outbreak was likely large because in Sicily ≈60% of cases may go unreported. Furthermore, we report only the cases that occurred in the villages of Messina province and that were reported to health authorities; but tourists from many other areas in Italy and some from outside Italy generally attend such events. Southern Italy has commonly been implicated as a venue for travel-associated brucellosis (2). In Italy, the overall incidence of brucellosis has gradually declined in the past 30 years, especially in northern Italy, where the disease is now reported only sporadically. This trend, however, has led to an increase in the percentage of total cases in Italians reported from the southern provinces of Calabria, Campagna, Puglia, and Sicily; of the 520 cases reported in 2003, 488 (93.8%) were reported from 4 southern regions, compared with 63.7% in 1994. Sicily alone reported 57.6% of the 2003 cases and for the past decade has had an average annual incidence of >100 cases per million (1,3). The disease is almost always caused by Brucella melitensis (4). The southern localization of the disease in Italy is obviously related to the relative high prevalence of infections in sheep and goats (5). Ovine and caprine population density is higher in the southern regions of Italy than in the rest of the country (6). The Italian brucellosis eradication plan consists of a test-and-slaughter practice. However, in Sicily a vaccination campaign with B. melitensis Rev.1 strain has been started. In 2003, ≈99% of the stock farms were tested, and ≈18% of them were infected (3). The major problems reside with small flocks that undergo frequent transhumance (seasonal movement of herds between regions with different climates) in isolated regions where testing by veterinarians is difficult or avoided by the owners (a typical drawback of test-and-slaughter practices). Technically, is not a cheese, but rather is a cheese by-product. The name ricotta means cooked again, referencing the production method. Ricotta is made from whey drained from tuma, provolone, and other cheeses. Heat is then used to separate, by precipitation, the remaining albumin from the whey left after making lactic acid/rennet–precipitated cheeses. It is eaten as is or used for food seasoning (e.g., classic Italian lasagna and ravioli). A cream made of sieved and sugar is used to prepare many desserts, like cannoli and cassata cake. Being cooked 2 times, should not contain viable Brucella organisms; however, shepherds sprinkle fresh milk on wicker baskets to refresh the they contain, thereby contaminating the product. Tuma is a typical Sicilian fresh cheese made from sheep's milk. It has a cylindrical appearance and is sold fresh, no more than 2 days old. It has no crust, and the dough is white or ivory-white without holes. The texture is very soft, tender, and wet. It is generally served with ham, wines, and fruits as a table cheese. Tuma cheese should be considered as the major vehicle of B. melitensis infection in Sicily. Although most similar dairy products produced in Sicily are derived from organized dairy companies and have been pasteurized, traditional delicacies from small villages may still cause brucellosis outbreaks.

Exposure of sheep to mosquito bites: possible consequences for the transmission risk of Rift Valley Fever in Senegal.

Rift Valley Fever (RVF) is a growing health problem in West Africa. In northern Senegal, the candidate vectors of this arbovirosis are Aedes (Aedimorphus) vexans Meigen and Culex (Culex) poicilipes Theobald (Diptera: Culicidae). Domestic ruminants are the reservoirs of the virus. A study was undertaken during the 2002 rainy season to assess spatial and temporal variations in exposure to mosquito bites in sheep herds, and to evaluate the possible consequences on the risk of RVF transmission to sheep. Mosquitoes were collected with sheep-baited traps. The number of Ae. vexans females (the predominant species during the 2002 rainy season) trapped per trap-night was the dependent variable in statistical analyses. The trapping periods were divided into six series of two to five consecutive days, from July to November 2002. Three temporary ponds were selected according to their ecological features: depth, bank slope, size and vegetation cover. Traps were laid on the pond bank and in the nearest available compound, close to the sheep night pen. Data were analysed using mixed-effects Poisson models. The explanatory variables were the trapping period, the pond, and the capture site. The exposure to mosquito bites varied according to the pond type, suggesting that the risk of transmission was spatially heterogeneous. However, there was no obvious trend in transmission risk due to the effect of the distance from the compound to the pond. The period with the highest exposure was in October, i.e. when transhumant herds left the Ferlo to relocate to their dry-season settlement. It is thus hypothesized that transhumance, the seasonal movements of herds, plays a significant role in the dissemination of RVF virus in the region.

Area use by white-lipped and collared peccaries ( Tayassu pecari and Tayassu tajacu) in a tropical forest fragment

We present the first long-term radio telemetry study of area use by white-lipped and collared peccaries in a tropical forest fragment. Population densities of both species in a 2178-ha fragment of semideciduous Atlantic forest in southeastern Brazil were similar to estimates from another regional fragment with 16 times the area. The population of 150 (±52) white-lipped peccaries was divided among 3–4 subherds. We observed a high frequency of switching of individuals among subherds and documented periodic subherd fusion. Seven to 22 collared peccary herds (mean herd size, 9) persisted in the main forest fragment. Average home range size for the white-lipped peccaries was 1871 ha (90% HM). This was similar to the few reliable estimates available from continuous tropical forests. Despite supposed area restrictions, white-lipped peccaries maintained distinct seasonal ranges with a minimum of overlap. Within seasons, subherds overlapped spatially, but were separated temporally. Average home range sizes of two radio-tracked collared peccary herds were 305 and 123 ha. Home range boundaries and seasonal ranges of collared peccary herds shifted minimally, and herd subgrouping was short-lived. Spatial overlap between the two peccary species varied seasonally with white-lipped herd movements. We discuss future research needs and management actions for conservation of these species in fragmented landscapes.

Identification of Anthropogenic Burning in the Paleoecological Record of the Northern Prairies: A New Approach

Despite recent interest in the North American fire record, paleoecological evidence for the deliberate burning of grassland by hunter–gatherers has not previously been sought. Through the analysis of grass phytoliths preserved in a sequence of buried soil horizons in the Lauder Sandhills, southwestern Manitoba, Canada, this article reconstructs a local grassland fire record for the past 5,000 years. I propose that an apparent peak in fire frequency shortly after 2,500 14C years b.p. corresponds to the deliberate burning of prairie by Sonota–Besant (Plains Woodland) hunter–gatherers, rather than climatic “forcing.” This practice, which is clearly documented in the historic record, may have functioned as a means of making bison–herd movements more predictable and may have enabled higher human carrying capacities in the Plains Woodland period. This hypothesis is meant to stimulate multidisciplinary discussion on a significant, but neglected, topic.

Multiple introductions from the Iberian peninsula are responsible for invasion of Crupina vulgaris in western North America.

• Crupina vulgaris is a relatively recent invader to grasslands and other open habitats in western North America. Like related Centaurea species, it was introduced from the Mediterranean region, where it does not exhibit ruderal behavior. Determining the number and sources of invasion founders allows fuller interpretation of colonization dynamics and recognition of potential intercontinental carriers, both critical factors for curbing the spread of invasive species. • We chose the molecular technique of random amplified polymorphic DNA (RAPD) to identify the number and sources of invasion founders from the eastern hemisphere, by comparing indigenous and invasive populations. • Our results indicated that the five North American populations derived from three or more successful invasion events whose founders originated in the Iberian peninsula. • Also inferred by the similarity clustering among eastern hemisphere populations is a more ancient origin of the genus to the east of the Mediterranean, a concept supported by the scarcity of suitable nonanthropic habitat in Spain. Its epizoochoric association with migratory movements of domestic herds suggests probable routes of migration first to southern Europe, then later to North America.

The Effects of Livestock Privatisation on Pastoral Land Use and Land Tenure in Post-Socialist Mongolia

Introduction Mongolian pastoralists differ from many pastoral peoples in their political, cultural and economic roles within their state. Pastoralists constitute 20-30 per cent of the total population of Mongolia (with some estimates suggesting they account for as much as 50 per cent), contribute significantly to the nation's GDP (over 30 per cent in 1996), and most belong to the dominant Khalkha Mongol cultural and ethnic group (MBDA and Tacis 1996). Mongolian pastoralists participate in a pastoral economy that has persisted, with apparent ecological and social sustainability, through several major political-economic transitions in the twentieth century. However, the shift in 1990 to a democratic form of government and the ongoing transition to a market economy once again call into question the future of herders' livelihoods and the resources on which they rely. This paper examines how the recent privatisation of livestock and dismantling of socialist herding collectives have affected land-use patterns and property relations among Mongolia's nomadic pastoralists. Prior to privatisation, the state was an all-permeating presence in the pastoral livestock sector. By 1960, all herders were members of herding collectives (negdels), whose territory was contiguous with that of administrative districts (sums). The state, supported by massive subsidies from its Soviet neighbour, undertook a successful rural development campaign centred around the creation of district (sum) centres, which provided social and technical infrastructure to herders (Potkanski 1993), as well as serving as economic engines for rural development by providing consumer goods, services and secure employment to sum residents (Muller 1995). Herding collectives also played a key role in allocating pasture and regulating the seasonal movement of herds. In the process of privatisation, the main influence of the state on herders' livelihoods and herding patterns has been in its sudden and conspicuous absence after decades of dominating every facet of the pastoral economy. Privatisation and the dismantling of collectives led to two major changes in the two districts studied: increasing differentiation between wealthy and poor households, and an influx of new herders to the countryside from settlements and cities. At the same time, the formal institutional structure for regulating pasture use, the collective, ceased to function. Common property theory proposes that as heterogeneity within a community of resource users increases, the likelihood of successful self-regulation of resource use declines, since the interests of community members diverge (Ostrom 1990) and opportunities for multiple interactions that lower the transaction costs of rule-making and enforcement decrease (Mearns 1996, Runge 1992, Taylor and Singleton 1993). Theory thus suggests that the rising heterogeneity in Mongolian herding communities due to increasing wealth differentiation and the influx of herders from towns and cities may influence the capacity of rural communities to organise pasture use among their own members (Mearns 1996). This paper uses data from a household survey conducted in two herding districts in Mongolia to explore how differences in wealth and migrant status affect access to resources, nomadic mobility, and patterns of resource use. Three general hypotheses were tested: (1) Access to productive resources differs among rich and poor herding households and new and old (migrant and long-time local) herding households; (2) differential access to productive resources affects herders' seasonal nomadic movements and resource-use behaviour; (3) new and old herders differ in norms of pasture use as reflected in their resource-use practices. The first section of the paper provides the background to the study, describing broadly the ecological contexts and pastoral production system, including typical patterns of seasonal movement and pasture use norms. …

Archaeozoological evidence for pastoral systems and herd mobility: the remains from Sos Höyük and Büyüktepe Höyük

AbstractCharacterization of pastoral economics in the archaeological record is recognized as being particularly difficult. While architectural evidence may provide ambiguous indicators of nomadism, animal remains afford greater clarity concerning assessment of herd and thus economic mobility. To highlight archaeozoological applications towards the analysis of herd movement as it may relate to the analysis and definition of economic systems, the mobility of the pastoral systems practised at Sos Höyük and Büyüktepe Höyük during the Early Bronze and Iron Age periods was investigated in terms of various facets of archaeozoological evidence. Sedentary occupation of these sites was suggested by the faunal remains on the basis of evidence, including use of seasonally available resources, relative abundance and representation of the main domesticates and dental data. These results suggest that analysis based upon multiple lines of archaeozoological evidence provides the most fruitful means of investigating pastoral mobility. Copyright © 2001 John Wiley & Sons, Ltd.

Environmental Knowledge and Pastoral Migration among the Wod Aabe of South-Eastern Niger

Introduction The present paper describes and analyses environmental knowledge among Wodaabe cattle raisers of West Africa with respect to their organisation of herd management. The Wodaabe pastoral system focuses mainly on raising Zebu cattle (na'i bodeeji) and has two primary aims: first, to guarantee and increase herd reproduction; second, to bring the herd with minimal loss in weight and size through the dry season when fodder is in short supply. For the Wodaabe, herd growth is not so much the outcome of a naturally given fecundity, but rather of proper animal nutrition. Of all measures that a cattle raiser may take to further his herd's prosperity, Wodaabe consider the good nourishment of the animals as the most important. To be taken seriously as a herder, a man has to regularly provide for the best seasonally available fodder, to avoid all influences that could reduce an animal's food intake, and to look out for anything that could stimulate its grazing activity. This orientation of pastoral labour is due to the Wodaabe's economic specialisation: whereas other groups of pastoral Fulani reduce their economic dependency on herds and the need to sell animals--for example by cultivating staples (Bierschenk 1997: 209)--Wodaabe herders concentrate on improving the physical condition of their cattle in order to optimise herd reproduction. By doing this the Wodaabe can sell more animals to obtain money for buying their staple food: millet. It is through high spatial mobility of herd and household together that Wodaabe herders translate their evaluation of the cattle's nutritional needs into practice. They move to combine a whole set of ecological conditions optimally, such as soil quality, relief and species composition; thereby they obtain fodder of the highest nutritional value at any point in the seasonal cycle. Pastoral mobility, therefore, is a means of organising the exploitation of seasonally variable fodder resources to reach the goal of optimising herd reproduction. When making decisions on where and how to feed the animals, though, herders have not only to respond to the cyclic fluctuations of resource availability in the Sahel, they have also to consider their animals' current and anticipated physical condition, which varies seasonally between well nourished and seriously emaciated. After a brief overview of Wodaabe categories of pastoral migration and their meanings in the local context of south-eastern Niger, I shall try to demonstrate the interrelations between: --Wodaabe environmental knowledge --the perceived potential of natural resources with respect to the pastoral aims of conserving and increasing herd fertility --the fact that natural resources as well as the physical condition of the herds are subject to high seasonal variation --herd movement as the principal instrument through which Wodaabe herders control the availability of eagerly sought after resources Data presented here concern a group of herders of the Siiganko'en lineage (taarde) of the Suudu Suka'el clan (lenyol) of the Wodaabe people (sg. Bodaado) (2) living in south-eastern Niger. Ecological knowledge, pastoral practice and use of mobility are not the same among all Wodaabe, and surely some parts of this description will be peculiar to Wodaabe living in the plains of the Lake Chad basin. Nevertheless, this paper is meant as a contribution to a general understanding of Wodaabe culture. Moreover, it seems reasonable to assume that a good deal of Siiganko'en knowledge and practice is understood and even shared by other Wodaabe groups (see Bonfiglioli 1981, 1990, 1991, Bonfiglioli et al. 1984, Dupire 1957, 1996, Stenning 1957, 1959). Hence, the use of the term `Wodaabe' is considered appropriate here. Clearly, even among the Siiganko'en, knowledge is not uniform, stable or uniformly distributed. However, questions of distribution, generation and communication of knowledge go beyond the scope of this paper. …

An Eminent Scapegrace Interviews an Eminent Divine: Stanley Huntley and Henry Ward Beecher, 1880

In 1878 Henry Ward Beecher finished building house tailored to his aspirations on thirty-six acre farm he had purchased some twenty years before, just east of Peekskill. That estate, which Beecher called Boscobel, got fair amount of attention both for agriculture and husbandry on one hand and for that noteworthy structure on other. The Brooklyn Daily Eagle often gave space to Beecher's sermons and to his other activities, so it must have come as no surprise when Eagle provided long, front-page treatment of BEECHER'S NEW HOME in issue of Sunday, June 20, 1880. The man who came sixty miles to interview Beecher had developed reputation for that sort of activity, as well as some others. This native New Yorker had reached thirty five years of age, and he had gained some renown or infamy for journalistic high-jinx. He did that especially in St. Louis stay in early and middle 1870s. On one occasion he exhausted patience of his employer, Stilson Hutchins, so fully that Hutchins fired him. Mollified by an inspired stroke of Huntley's cheekiness, Hutchins re-hired him and, in 1877, took him to Washington, D. C., to help launch Washington Post. There especially, garnered that reputation as an interviewer. Republican President Rutherford B. Hayes and his secretary of state, William M. Evarts, experienced-not very happily-- attentions of this prankish Democratic newsman. The former vfs-a-vfs has interest because in 1879 encountered young woman from Fremont, Ohio, whose family knew Hayes family. Shortly, Florence Chance married Stanley Huntley. In interviewing that member of Hayes cabinet, impish journalist showed well his satiric capacity. The phlegmatic Evarts had little enthusiasm for his visitor, and that interview had more comedy than content. When informed Secretary that he sought his views, Evarts' face assumed expression of an eight-day clock with works made of wood and hands pointing to just about time for me to go. Simply, interviews often had questionable, even bogus quality. ranked high where such suspicion was concerned (Saum, Huntley Interviews). Huntley's finest moment as an interviewer had occurred almost year before his visit with Beecher. The sixty miles to comforts at Peekskill bore little resemblance to his long trek from Bismarck, Dakota Territory, to Milk River country near Canadian border where interviewed Sitting Bull. For an inspired, rococo few months had edited Bismarck Tribune, providing nearly unmatched moment of frontier journalistic frolic. Ending his stay on tripod in Bismarck in spring, 1879, accepted commission from Chicago Tribune to venture into northern Montana country where Sitting Bull's fugitives came back across line to meet northward movement of buffalo herds. Almost exactly three years after Little Big Horn disaster Huntley's interview with Sitting Bull covered most of front page and part of second page of July 4, 1879, Chicago Tribune. Here as elsewhere, not all rushed to believe. The Eagle, for example, noting that originated in Brooklyn, added that he combined a strong imaginative ability with the faculty of usually being at considerable distance from persons and places described (Eagle, July 11, 1879). Later in 1879 began his noteworthy stay at Brooklyn Daily Eagle. Mostly, his contributions came in weekly column, Salad for Sunday. That varied fare became best known for crotchets and splenetics of irascible Mr. Spoopendyke whose outbursts often derived from vacuously innocent misunderstandings of Mrs. Spoopendyke. The Spoopendyke Papers became known throughout country, rightly so. The long interview with Beecher was signed, S. H., and word about that should be offered here. On various occasions beginning in late 1879, six months before Beecher interview, front-page specials in Eagle appearing over those initials admit of no doubt that they came from Huntley. …

Success and failure of reindeer herding in Greenland

Animal husbandry is a recent innovation in Greenland, specifically reindeer husbandry is less than 50 years old. Reindeer husbandry was first established in mid-west Greenland and later in southern Greenland. The Greenland hunter tradition and culture is, however, still dominant in many communities. During the 1980s and 1990s, the incompatibility of these two traditions resulted in the failure of reindeer husbandry in mid-west Greenland. There were neither herding nor seasonal herd movements. Animals remained year round on the winter range, which was destroyed as lichens were trampled every summer. Without seasonal herd movements both sustainable range use and control of the herd were lost. Today, there are just two semi-domestic reindeer herds left, and both are in southern Greenland. One herd is commercially successful, and the other is under development. In mid-west Greenland, semi-domestic reindeer husbandry officially ended in 1998, and a hunt was initiated to remove the remaining population. Possibly, by the year 2000 any animals left in this region will be considered wild caribou.

Lekking, resource defense, and harassment in two subspecies of lechwe antelope

For lek-breeding in ungulate populations to continue, benefits to males defending lck territories and to females visiting leks must outweigh the costs. In this study, Kafue lechwe males on leks gained higher mating rates than nonlekking males, a result of sexually receptive females leaving herds and aggregating on leks. When die numbers of females on leks were experimentally reduced, benefits to males decreased, resulting in males gradually abandoning lek territories. A comparison with a population of nonlekking, resource-defending black lechwe showed that mating attempts by estrous females in herds were disrupted by harassing males eight times more frequently in a population of lek-breeding Kafue lechwe than in the nonlekking black lechwe. Despite the fact that there were fewer Kafue lechwe females on single territories, harassment of estrous females by males was greater on single territories of Kafue lechwe than on leks and greater than on black lechwe resource territories. Females were also absent on Kafue lechwe single territories for long periods because of erratic widespread movements of compact herds resulting from unpredictable distributions of resources. In contrast, black lechwe females were more evenly dispersed over homogeneous resources and for a given territory, females were likely to be present most of the time. Therefore, unlike black lechwe, male Kafue lechwe find it uneconomical to defend resource territories. Thus, costs to estrous females mating off leks and the absence of benefits to males attempting to defend resource-based territories may be important cofactors in the appearance of lek-breeding in some ungulate populations.

Management and demographic factors associated with seropositivity to transmissible gastroenteritis virus in US swine herds, 1989–1990

Serum neutralization testing was used to determine transmissible gastroenteritis (TGE) titers of up to 10 sows per herd (mean 8.7, median 10) for 392 herds that participated in the 3 month monitoring of sows and litters in the National Swine Survey. Of the sampled herds, 101 (25.8%) had sow seroprevalences of at least 80%, 79 (20.1%) had seroprevalences between 10 and 79%, and 212 (54.1%) were seronegative. For evaluation of risk factors for TGE seropositivity, analysis was restricted to herds with at least five tested sows and either 0% or at least 20% seropositive sows. In the logistic regression analysis, a herd was considered seropositive if at least 20% of sampled females had titers of 1: 8 or higher ( n = 160), and a herd was seronegative if all females had titers of under 1: 8 ( n = 178). Factors considered for inclusion in logistic regression models included breeding herd size, biosecurity measures, pig introductions and movements, and access of possible nonporcine reservoirs to the facilities with pigs. After controlling for the effects of season, number of samples tested and TGE vaccination history, large female breeding herd size (at least 500 sows compared with the reference category of 100–199 sows) and purchase of more than 25 pigs from non-specific pathogen free (SPF) herds were associated with significantly ( P<0.05) higher odds of herd seropositivity (odds ratios 4.9 and 3.9, respectively). There was some evidence ( P = 0.08) of an increased risk of seropositivity when there were more than two swine herds within a 3 mile radius of the study herd.

Establishment and early persistence of ten forage legumes under three grazing regimes in southern Mozambique

Leucaena leucocephala, Clitoria ternatea, Macroptilium atropurpureum cv. Siratro, Cassia rotundifolia cv. Wynn, Macrotyloma axillare cv. Archer, Stylosanthes guianensis var. guianensis cv. Graham, S. guianensis var. intermedia cv. Oxley, S. hamata cv. Verano and S. scabra cv. Fitzroy and cv. Seca were screened for their ability to establish at five coastal sites of Maputo province, Mozambique. Three grazing treatments were imposed in strips: continuous access, dry-season-only access and an ungrazed control. Grazing pressure was dependent on the movement of communal cattle and goat herds. Mean seedling emergence ranged from a low of 28% for Graham to a high of 78% for Siratro. First season mean seedling vigour (1-10) differed (P = 0.01) among entries and ranged from 4.0 for Graham to 8.0 for Seca. First-year dry season individual plant vigour showed an interaction (P = 0.1) between grazing treatment and entry with Siratro and Seca plots averaging 3.0 or better. Dry season plot cover likewise showed an interaction (P = 0.002) between treatment and entry with Siratro and Seca averaging over 20%. Second rainy season vigour showed differences (P = 0.03) among species only, with Siratro and Seca having values over 7.0. Plot cover was likewise differentiated only among species (P = 0.0006) with Siratro and Seca both covering 59% of their plots, superior to C. ternatea (19%), L. leucocephala (9%), Archer (7%), Verano (16%), Fitzroy (28%), Graham (29%), and Wynn (4%). Oxley (36%)was undifferentiated from either group. Overall, Siratro and Seca had the best establishment whilst Oxley showed promise. Deferred grazing generally appeared to have little effect on establishment. Keywords: cassia rotundifolia ; clitoria ternatea ; forage; forage banks; forage legumes; grazing pressure; grazing treatments; leucaena leucocephala ; macroptilium atropurpureum ; macrotyloma axillare ; mozambique; persistence; plant vigour; stylosanthes guianensis ; stylosanthes hamata ; stylosanthes scabra ; tropical legumes African Journal of Range & Forage Science , 10(3): pp. 135-139

The commuting system of Serengeti spotted hyaenas: how a predator copes with migratory prey. II. Intrusion pressure and commuters' space use

Abstract. In the Serengeti, Tanzania, spotted hyaenas, Crocuta crocuta Erxleben, regularly left their clan's territory to feed on the nearest migratory herds ('commuting trips'). The mean commuting distance was 40 km. Commuting locations matched the movements of the migratory herds throughout the year. The distribution of commuters was compatible with the hypotheses that commuters (1) minimized contact with resident clans and (2) utilized areas where they were assured of locating migratory herds. The proportion of clan members commuting declined as prey abundance in the clan's territory increased. Territories were visited by non-residents (commuters) throughout the year but the number of foraging commuters increased substantially when large migratory herds entered a territory. During encounters between residents and intruders, residents adjusted their behaviour according to the context of the encounter: residents ignored commuters 'in transit', responded aggressively to commuters at kills, and engaged in prolonged clashes with neighbouring clans. A comparison with the space use systems of other carnivores indicates that the commuting system of spotted hyaenas in the Serengeti is unique. It is hypothesized that the development of the commuting system was contingent on several adaptive behavioural, morphological and physiological specializations.

Seasonal abundances of the harbor seal (Phoca vitulina richardsi Gray 1864), at Punta Banda Estuary (B.C., Mexico)

In order to know the present abundance and seasonal variability of the seals (Phoca vitulina richardsi Gray, 1864) hauling at the inner northwest portion of Punta Banda Estuary (Baja California, Mexico), 40 counts were carried out between November 1988 and August 1990. The average abundance during the study period was 52 individuals, although a significant seasonal variability was noted. The largest mean abundance occurred in spring (X = 69; n = 12; range = 31-110) and it was the best season to assess the number of seals that use the estuary. The lowest abundance was recorded in summer (X = 28; n = 5; range = 2-72) while in autumn the number of seals was lower than in winter and spring (X = 31; n = 8; range = 18-48). The maximum seal counts were noted in winter, although their average abundance was lower than in spring (X = 58; n = 15; range = 18-151) since the herd increased by the occasional presence of pups and juveniles. No relationship was found between the abundance of seals and the sea level. The seasonal variation in the size of the herd was associated with its breeding season which occurs late in winter and with herd movements to other near haul-out sites.

Conservation Practices at an Upper-Elevation Village of West Nepal

Chimkhola, an upper-elevation village located on the southeastern flank of Dhaulagiri Himal, has virtually no irrigated agricultural fields, but large areas of widely dispersed, rain-fed fields and large areas of forest and alpine pastures. Villagers fertilize agricultural fields by taking livestock onto fields for one to several weeks prior to planting so that manure falls directly on the soil. The movement of herds from field to field, and to forest when all fields are planted, determines and coordinates the village subsistence system. Of the 17,035 dry weight kg of forest products collected by the average household each year, 32.8 % is fuelwood for herders, 23.8% is livestock fodder, and 19.2% is fuel for houses. Shortages of forest products have relatively recently begun to affect Chimkhola, and villagers have established a series of regulations designed to conserve forests and needed forest products. These measures, however, seem inadequate to halt the forest degradation process. Unless villagers insure forest regeneration by managing livestock grazing and browsing, a change that seems unlikely, the current communally controlled agro-silvo-pastoral system will probably dissolve into one of individual action, with increasingly intensive agricultural production on fewer, more spatially concentrated holdings and with fewer livestock which are kept close to the house and fed fodder from private trees.