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While protected areas are a centrepiece of conservation, populations of animals in protected areas can still be subject to considerable human influence. Conservation theory suggests that many species should live at lower densities at the periphery of protected areas compared with the core area. Similarly, but more specifically, species subject to exploitation are expected to have lower densities in areas close to human settlements compared with more remote areas. Drawing upon distributional data of eight large African herbivore species (buffalo Syncerus caffer, elephant Loxodonta africana, giraffe Giraffa camelopardalis, impala Aepyceros melampus, topi Damaliscus lunatus, warthog Phacochoerus africanus, waterbuck Kobus ellipsiprymnus and zebra Equus quagga) sampled using ground surveys in 1995 and 1996, and seven large herbivore species (the same species without impala) sampled using aerial surveys from 1987 to 2009, we fitted logistic regression models and used an information theoretic model selection approach to test these two hypotheses in an East African savannah national park subject to illegal hunting from outside. In the vast majority of herbivore species, occupancy was not substantially affected by being close to the edge of the park or in close proximity to human villages. Furthermore, population declines witnessed in this protected area were not reflected in reduced occupancy near park boundaries. We conclude that assumed distributional differences between peripheral and core parts of reserves are not necessarily supported by empirical evidence, and that population declines within reserves do not inevitably proceed from boundaries inwards.

Rates of lightning mortality in communities on the western shore of Lake Malawi are higher than any other reported rate in the world: 419 strike victims per million people per annum and 84 deaths per million per annum. To document the background to this phenomenon, we conducted comprehensive household interviews with surviving victims and witnesses of every case of lightning strike in seven administrative areas around Nkhata Bay, Malawi. We find that the consequential lightning strikes are significantly more common in the rainy season and during the morning. Among those victims struck by lightning, there is an average ratio of approximately one death to four injuries, which is substantially higher than the commonly accepted ratio of 1:10. Children and adults are at equal risk of being struck. If struck, the probability of death is greater when the victim is outside in the open or outside under cover than indoors under a tin or thatched roof, but is unaffected by different kinds of footwear or whether it is raining. Reported explanations for strikes often center on witchcraft or other forms of social conflict. Our findings extend the study of consequential lightning strikes in the developing world and highlight cultural factors associated with this hazard. We end with recommendations for reducing the risk of lightning for rural populations.

Pinnipeds vary in adult pelage color and pattern ranging from uniform white to black or brown and from solid coloration to subtle spotted or bold markings. Moreover, pelage color often differs by sex and age with neonates having radically different color and patterning from those of adults. We explored the functional significance of these patterns in 34 species of pinniped using comparative phylogenetic analyses. We found strong evidence to support the hypothesis of background matching on land because species in which adults or pups have white pelage live in Arctic regions and are subject to terrestrial predation. We also found evidence supporting the hypothesis of background matching at sea because spotted species forage in well-lit shallow waters on-shelf and dark pinnipeds forage in deep dark waters off-shelf. Neonates are black for species lacking terrestrial predators on islands or in caves where selection on crypsis is relaxed. Distinctive markings may be used for intraspecific communication. Sexually dichromatic pinnipeds are highly polygynous and copulate on land, suggesting a role for male coloration in contests for access to females. Functional differences in the coloration of pinnipeds and cetaceans reveal differences in underlying selection pressures, in particular those derived from pinnipeds' amphibious lifestyle.

Several large mammals such as the black and white giant panda Ailuropoda melanoleuca, the mottled giraffe Giraffa camelopardalis, and striped and russet okapi Okapia johnstoni have striking and wel...

IT HAS BECOME COMMONPLACE to remark that humans are now the dominant environmental force on the Earth. The indications are strong and diverse. They range from paleontologists reaching a consensus that humans contributed to megafaunal extinctions on at least two continents, North America and Australia;1 recognition that formerly intact marine ecosystems have changed enormously;2 suggestions that climate has changed sufficiently that no ecosystem is immune from alterations in species composition;3 remarks that pollution is widespread even in Antarctica;4 and arguments that human predation on mammals is pernicious and the principal driver of changes in phenotypic traits of exploited species in many areas.5 Some scientists use geographic data to show that human activities affect almost every terrestrial system (e.g., the human footprint6). Indeed, the current epoch is now being referred to as “the Anthropocene,”7 which has led geologists to formally debate stratigraphic evidence for this new phenomenon and to argue over not if but when it began.8 With the catchword Anthropocene in ascendancy, one might easily come away with the impression that nowhere on Earth is natural, in one of the word’s specific meanings of ecosystems being untouched by humans,9 and indeed it is common to hear the phrase “humans have altered everything.”

Several species of terrestrial carnivores (Mammalia: Carnivora) have bold contrasting color patterns that, in some species, apparently signal possession of noxious anal gland secretions, or even physical strength and great ferocity; yet the evolutionary drivers of both placement and patterning of these contrasting pelage colors on the body, and the ecological selection pressures underlying them, have yet to be systematically examined. Here we explore these issues and find not only that both boldly colored and dichromatic species do indeed often use anal gland secretions for defense, but also that such species are stockier, and live in more exposed habitats where other forms of antipredator defense are limited. We also show that white dorsa are found in sprayers that are primarily nocturnal; that horizontal stripes are found in species that have an ability to spray anal secretions accurately; and that facial stripes are found in burrowing species that typically leave only their heads exposed to attack. Our phylogenetic reconstructions suggest that aposematic coloration has evolved more than once in terrestrial carnivores. We finish by outlining five evolutionary routes for patterns of pelage coloration in this taxon.

Although long-term monitoring is viewed as an essential part of conserving wildlife populations, it is currently carried out in surprisingly few protected areas in Africa. Here, data from a 16-year vehicle transect monitoring programme in Katavi National Park, western Tanzania, are presented. These data provide information on large mammal densities, identify declines in populations of several large mammal species as based on encounter rates, support worrying trends observed in aerial census data and shed light on the effectiveness of recent changes in legal protection. Ground and aerial surveys confirmed that waterbuck, topi, warthog, lion and spotted hyaena populations are all in decline and that this should be a cause for concern. Counting animals by driving vehicle transects is relatively easy and inexpensive to carry out, and data here show that such counts have several pay-offs for conservation managers especially in identifying population declines; counts should be employed more often in East Africa and elsewhere.

Cetaceans show many of the classic mammalian colouration patterns, such as uniform colouration, countershading, and prominent patches of colour, all within one relatively small taxon. We collated all the functional hypotheses for cetacean colouration that have been put forward in the literature and systematically tested them using comparative phylogenetic analyses. We found that countershading is a mechanism by which smaller cetacean species may avoid being seen by their prey. We discovered that prominent markings are associated with group living, fast swimming, and ostentatious behaviour at the surface, suggesting that they function in intraspecific communication. White markings on several parts of the body seem to be involved in the capture of fish, squid, and krill. Therefore, several different selection pressures have shaped the great diversity of skin colouration seen in extant cetaceans, although background matching, disruptive colouration and interspecific communication do not appear to be involved.

Reptiles of Katavi National Park, western Tanzania, are from different biomes Tim Caro*, Owen ‘Squack’ Evans, Emily Fitzherbert, Toby A. Gardner, Kim Howell, Robert Drewes and H. Bradley Shaffer Center for Population Biology and Department of Wildlife, Fish and Conservation Biology, University of California, Davis, CA 95616, U.S.A., Tanzania Wildlife Research Institute, PO Box 661, Arusha, Tanzania, PO Box 345, Usa River, Tanzania, Conservation Science Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, U.K., Department of Zoology and Wildlife Conservation, University of Dar es Salaam, Tanzania, PO Box 35064, Dar es Salaam, Tanzania, California Academy of Sciences, 55 Music Concourse Drive, Golden Gate Park, San Francisco, CA 94118, U.S.A. and Center for Population Biology and Department of Evolution and Ecology, University of California, Davis, CA 95616, U.S.A.

Turtle carapaces clearly function as antipredator adaptations, but their varied structure has rarely been matched to differential predation pressure in nature. In addition, the role of antipredator behaviors, and how they interact with morphological defenses in turtles, is poorly understood. Here we show that a small turtle, Pelusios subniger, is found predominately in pools and watercourses where the Nile crocodile, Crocodylus niloticus, a species that imposes intense predation pressure on them, is absent. Our ecological data are consistent with the interpretation that P. subniger can share the same ecological landscape with C. niloticus through behavioral avoidance.

Tanzania holds most of the remaining large populations of African lions (Panthera leo) and has extensive areas of leopard habitat (Panthera pardus), and both species are subjected to sizable harvests by sport hunters. As a first step toward establishing sustainable management strategies, we analyzed harvest trends for lions and leopards across Tanzania's 300,000 km(2) of hunting blocks. We summarize lion population trends in protected areas where lion abundance has been directly measured and data on the frequency of lion attacks on humans in high-conflict agricultural areas. We place these findings in context of the rapidly growing human population in rural Tanzania and the concomitant effects of habitat loss, human-wildlife conflict, and cultural practices. Lion harvests declined by 50% across Tanzania between 1996 and 2008, and hunting areas with the highest initial harvests suffered the steepest declines. Although each part of the country is subject to some form of anthropogenic impact from local people, the intensity of trophy hunting was the only significant factor in a statistical analysis of lion harvest trends. Although leopard harvests were more stable, regions outside the Selous Game Reserve with the highest initial leopard harvests again showed the steepest declines. Our quantitative analyses suggest that annual hunting quotas be limited to 0.5 lions and 1.0 leopard/1000 km(2) of hunting area, except hunting blocks in the Selous Game Reserve, where harvests should be limited to 1.0 lion and 3.0 leopards/1000 km(2) .

Comparative studies of pelage coloration in mammals suggest that certain prominent markings on an otherwise uniform pelage background serve in communication. We matched the position and coloration of contrasting markings on the bodies of all eventoed ungulates to ecological and social variables in order to ask whether marks are used in communication generally, as a signal to predators, or as a signal to conspecifics. Controlling for phylogeny, we found that many marks are located in prominent visible positions on the body; that flank marks seem to amplify stotting and leaping, which are pursuit deterrent signals; and that front leg marks may amplify foot stamping, an antipredator signal. We found that upper leg markings, particularly markings on the podials, are associated with group living hinting at an intraspecific communicatory function. Surprisingly, we found that contrasting marks do not reliably indicate position of scent glands across this taxon and that many white marks may have a cryptic function. These results extend and contradict those of previous analyses and force us to conclude that contrasting pelage marks have a number of functions in this taxon including pursuit deterrence, intraspecific signaling, and possibly even crypsis. Key words: color patches, intraspecific communication, pursuit deterrence, signals, ungulates. [Behav Ecol]

Connectivity is regarded as vital in conservation planning but the whereabouts of remaining wildlife corridors and dispersal areas in most tropical countries are poorly documented. With local experts, we compiled an annotated list of the most important wildlife corridors remaining on mainland Tanzania, information on the status of each corridor, wildlife using these corridors, and threats to them. We discovered that the concept of a wildlife corridor differs greatly between different people working in the same country, so we divided these into five working categories. The most common categories were those identified by known movements of animals between two protected areas, or simply proposed connections between important habitats. In Tanzania, the majority of documented corridors now seem to be in a critical condition, that is, they may have less than 5 years remaining before they disappear, judging by current rates of land use change. Five corridors are in extreme condition and could disappear within 2 years unless immediate action is taken. These pressing problems – and our experience in Tanzania – indicate that surveys of remaining wildlife corridors may need urgent documentation in other countries too and that collators should maintain loose definitions of corridors, accept data of variable quality and give information to authorities as soon as possible in order to maximize the chances of saving these conservation assets.

Weaponry is ubiquitous in male ungulates and is driven by intrasexual selection, but the mystery surrounding its sporadic presence in females remains unsolved. Female horns are often smaller and shaped differently to male horns, suggesting a different function; indeed, hypotheses explaining the presence of female horns include competition for food, male mollification and defence against predators. Here we use comparative phylogenetic analyses to show that females are significantly more likely to bear horns in bovids that are conspicuous due to large body size and living in open habitats than inconspicuous species living in closed habitats or that are small. An inability to rely on crypsis or take refuge in deep vegetation has apparently driven the evolution of horns for defence against predators in female bovids, a finding supported by many field observations. Typically, exceptions are small species where females are territorial (e.g. duikers) and use horns in intrasexual contests. Furthermore, we suggest that conspicuousness and territoriality hypotheses may explain other instances of female cranial weaponry (i.e. antlers and ossicones) in other horned ruminants. Our phylogenetic reconstruction indicates that the primary function of horns in females is linked to antipredator defence in most clades, but occasionally to intrasexual competition in others.

We apply an age- and stage-structured model incorporating varying harem sizes, paternal care and infanticide to examine the effect of hunting on sustainability of populations. Compared to standard carnivore and herbivore models, these models produce different outcomes for sustainable offtake when either adults, or adult males are harvested. Larger harem size increases sustainable offtake whereas paternal care and infanticide lowers it. Where males are monogamous, populations are vulnerable to male offtake, regardless of paternal care. Surprisingly, an incidental take of 10% of other age–sex-classes has very little effect on these findings. Indiscriminate (subsistence) hunting of all age–sex classes has a dramatic effect on certain populations. Applying these behavior–sensitive models to tourist hunting in the Selous Game Reserve, Tanzania, we find that across the Reserve hunting quotas were generally set at sustainable rates except for leopard (Panthera pardus). In certain hunting blocks within the Reserve, however, quotas for eland (Taurotragus oryx), hartebeest (Alcelaphus buselaphus), lion (Panthera leo), reedbuck (Redunca arundinum), sable antelope (Hippotragus niger), warthog (Phacochoerus aethiopicus) and waterbuck (Kobus ellipsiprymnus) are set at unsustainably high rates. Moreover, particular blocks are consistently awarded high quotas. Behaviorally sensitive models refine predictions for population viability, specify data required to make predictions robust, and demonstrate the necessity of incorporating behavioral ecological knowledge in conservation and management.

Knowledge and attitudes of children towards wildlife and the environment were assessed through questionnaires given to 366 children in 9 schools in southwest Guyana. Children's responses revealed that they had a general knowledge of wildlife but knew few details about specific species. Respondents thought that wildlife was important but were nonetheless tolerant of several forms of environmental exploitation. Visits by conservation organizations, Conservation International and Foster Parrots, were shown to increase appreciation of wildlife and the need to set up more protected areas, but unless programmes were concentrated and sustained they had little effect on attitudes towards environmental utilization and exploitation. Experience of the natural world in terms of owning a domestic animal or pet, having visited a zoo, or being a member of a wildlife club had little impact on children's knowledge of wildlife and did not change attitudes to utilization and exploitation. Surprisingly, Guyanese children did not have particularly positive views about classic flagship species, such as jaguars, giant anteaters and tapirs, when compared to other species. Our findings suggest that zoos, wildlife clubs and conservation organizations could enhance the dissemination of their message through making more frequent and sustained visits, imparting more detailed knowledge, and exposing children to the potential dangers of utilization and exploitation; also that conservation organizations should reassess their use of standard flagship species in South America.

Aim To highlight and examine apparent paradoxes in assessing the effectiveness of different forms of land-use for biodiversity conservation. Location Tanzania. Methods We compare and contrast the findings of two recent and seemingly conflicting studies on the effectiveness of conservation protection strategies in Tanzania. We evaluate these studies in the context of a wider body of evidence relating to the problem of determining protected area performance. Results We highlight the importance of landscape-scale management approaches for biodiversity conservation; establishing clear management and monitoring objectives in advance; the interrelation between the choice of target species and the appropriate spatial scale over which to measure their fate; and differences between snapshot and longitudinal scales in assessing the effectiveness of conservation strategies. Main conclusions Protected area assessments should not promote an isolated focus on particular conservation targets or methods of monitoring and evaluating the effectiveness of conservation strategies. Instead we argue for a more pluralistic approach to evaluating conservation performance that can help to reveal where potential synergies in tackling different objectives exist, and clarifying the trade-offs when they do not.

We review the ecological rationale behind the potential compatibility between top predators and biodiversity conservation, and examine their effectiveness as surrogate species. Evidence suggests that top predators promote species richness or are spatio-temporally associated with it for six causative or noncausative reasons: resource facilitation, trophic cascades, dependence on ecosystem productivity, sensitivity to dysfunctions, selection of heterogeneous sites and links to multiple ecosystem components. Therefore, predator-centered conservation may deliver certain biodiversity goals. To this aim, predators have been employed in conservation as keystone, umbrella, sentinel, flagship, and indicator species. However, quantitative tests of their surrogate-efficacy have been astonishingly few. Evidence suggests they may function as structuring agents and biodiversity indicators in some ecosystems but not others, and that they perform poorly as umbrella species; more consensus exists for their efficacy as sentinel and flagship species. Conservation biologists need to use apex predators more cautiously, as part of wider, context-dependent mixed strategies. Copyright © 2008 by Annual Reviews. All rights reserved.

Intraguild interactions play a prominent role in shaping ecological communities, so over evolutionary time one might expect that species that co-occur with a large number of competitors would evolve morphological and behavioural adaptations to ameliorate risks of intraguild competition and predation. In four different sets of analyses that took account of habitat stratum, habitat type and activity pattern on competition and predation pressure, significant differences were found in the extent to which Ameri can carnivore families potentially encounter other carnivores. Members of largely omnivorous families, Canidae and Ursidae, co-occur with a greater proportion of potential competitors than members of families with more specialized diets. We found that members of the Mustelidae family may reduce competition by being arboreal or aquatic, and that members of the Procyonidae and Mephitidae are potentially under great predation pressure but the former reduce this threat by being arboreal whereas Mephitidae likely reduce predation through advertising noxious secretions. In one analysis, conspicuous species with both contrasting facial and body colouration co-occurred with more potential predators than other less striking species of carnivore suggesting that intraguild predation is an evolutionary driver of contrasting coat colouration in carnivores. These quantitative analyses suggest that several facets of carnivore niche occupation and morphology have evolved in response to intraguild pressures.

We describe tree diversity, forest community composition and vegetation structure in dry forest miombo woodland in the Katavi-Rukwa ecosystem of western Tanzania. Tree diversity was high (45 families, 117 genera, 229 species) and concentrated in the Fabaceae (30 genera, 73 species). A strong majority (75%) of 19,481 sampled trees were aggregated in just 12 genera spread among 11 families, with individuals in the genera Grewia (17.42%), Markhamia (13.20%) and Combretum (13.13%) dominating abundance. Assessing dominance in terms of a combined importance value (IV300, summed relative abundance, basal area and frequency), showed Terminalia sericea , Combretum adenogonium , and C. colinum as the dominant tree species. Thus, woodlands in this region are atypical of the miombo biome in which it is embedded with only six of fifty 0.1 ha quantitative plots dominated by species in one of the classic miombo genera ( Brachystegia , Julbernardia , or Isoberlinia ). Ordination of data from these 50 plots revealed a diffuse structure of communities. Moreover, trees were found to be spatially clumped within, as well as among, plots. By documenting how the Katavi-Rukwa ecosystem is comprised of a patchwork of locally dominant common trees intermixed with a diverse assemblage of less common species, which have few specific associations with particular dominants, our study begins to fill an important gap in understanding composition and structure of dry forests that still occupy so much of southern-central Africa.

Some conservation organizations publish magazines that showcase current conservation and research projects, attract new subscribers and maintain membership, often using flagship species to promote these objectives. This study investigates the nature of flagship species featured on the covers of ten representative US conservation and nature magazines, Defenders, National Wildlife, Wildlife Conservation, Zoonooz, Nature Conservancy, Outdoor America, Sierra, Audubon, California Wild and Natural History. Operationally defining flagship species by diet, taxonomic order, body size and IUCN status, we found that magazines tend to use mammal and bird species rather than invertebrate, fish, amphibian, reptile or plant taxa on their covers. Featured birds were mostly omnivorous or piscivorous, large-bodied and of little conservation concern; featured mammals were mainly carnivorous or herbivorous, large-bodied and of considerable conservation concern. These analyses confirm, for the first time, anecdotal observations about conservation organizations focusing their publicity and programmes on large, charismatic species to raise awareness and funds and raise the spectre that the public may be exposed to only a selected sample of conservation problems.

We sampled small mammals in numerous habitat types throughout the wet and dry seasons in and around Katavi National Park, a remote protected area in western Tanzania consisting of miombo woodland and seasonal floodplains. Although trap success was relatively low (6.6%), a minimum of 23 species were caught in over 11,000 trap nights. These were Crocidura hirta, Crocidura luna, Saccostomus campestris, Dendromus mystacalis, Steatomys pratensis, Tatera boehmi, Tatera leucogaster, Acomys spinosissimus, Aethomys chrysophilus, Aethomys kaiseri, Arvicanthis niloticus, Grammomys dolichurus, Lemniscomys rosalia, Lemniscomys striatus, Mastomys natalensis, Mus musculoides, Mus triton, Pelomys fallax, Graphiurus murinus, Petrodromus tetradactylus and probably Crocidura nanilla, an unidentified species of Mus, and an unidentified rodent species. Overall species richness and abundance did not differ between wet and dry periods of the year. There were few differences in species richness between major habitat types but relative abundance was the highest in cultivated landscapes. Species communities differed between habitats and detailed environmental measures showed that species were more diverse and lived at greater abundance in taller vegetation. Species-specific habitat preferences uncovered here extend a number of findings from several earlier studies in miombo woodland. This study highlights the importance of taking quantitative measures of vegetation at both coarse and fine scales, and the necessity of trapping across a wide variety of habitats.

Scavenging by large-bodied vertebrates is observed in many ecosystems but has rarely been quantified. Here we document the timing and order of scavenger arrival at 639 cheetah kills in Serengeti National Park, Tanzania, focusing on ecological and heterospecific factors that may impact detectability of carcasses. We found that small-, medium- and large-sized vultures, jackals, spotted hyaenas and lions were more likely to be present at the carcasses of large-bodied than small-bodied prey. Lions and spotted hyaenas were less likely to locate kills in tall grass; medium-sized vultures were likely to arrive before both large- and small-sized vultures. Spotted hyaenas and vultures were likely to be present at kills simultaneously. Despite numerous anecdotal accounts, we did not find that hyaenas use alighting vultures as a means of locating food. Our findings show that environmental variables and other scavenger species strongly influence scavenger arrival at carcasses in this ecosystem. Resume Le pillage des carcasses par des vertebres de grande taille s'observe dans de nombreux ecosystemes, mais on l'a rarement quantifie. Nous documentons ici les delais et l'ordre d'arrivee des charognards sur 639 proies tuees par des guepards dans le Parc National de Serengeti, en Tanzanie, en nous focalisant sur les facteurs ecologiques et heterospecifiques qui peuvent influencer la detectabilite des carcasses. Nous avons decouvert que les petits, moyens et grands vautours, les chacals, les hyenes tachetees et les lions etaient plus susceptibles de se retrouver pres de carcasses de grande taille que sur des petites proies. Les lions et les hyenes tachetees etaient moins susceptibles de localiser les proies dans les hautes herbes; les vautours de taille moyenne avaient tendance a arriver avant les grands et les petits vautours. Les hyenes tachetees et les vautours etaient susceptibles d'arriver pres des proies en meme temps. Malgre de nombreuses anecdotes allant dans ce sens, nous n'avons pas trouve que les hyenes utilisaient l'envol des vautours comme moyen de localiser la nourriture. Nos decouvertes montrent que des variables environnementales et les autres especes de charognards influencent fortement l'arrivee des charognards pres des carcasses dans cet ecosysteme.

Considerable controversy surrounds the effectiveness of strictly protected areas that prohibit consumptive resource use. For Tanzania we compared temporal changes in densities of large herbivores among heavily protected national parks and game reserves, partially protected game-controlled areas, and areas with little or no protection. Comparisons based on surveys conducted in the late 1980s and early 1990s versus the late 1990s and early 2000s showed three consistent patterns across the country. First, significant declines in the densities of large herbivores between these two snapshots in time overwhelmingly outnumbered significant increases in all protection categories. Second, more species fared well (increased significantly or showed no significant change) in strictly protected national parks than in areas with partial or no protection and in heavily protected game reserves relative to areas with no protection. Third, significantly more species fared poorly (densities declined or were too low to detect a decline) than fared well in areas with partial or no protection. Our results show that although heavy protection was generally more effective in maintaining large herbivore populations than partial or no protection, continued long-term monitoring is needed in Tanzania to inform managers whether large herbivores are experiencing declining population trends even within heavily protected areas.

We present data on sample richness, relative abundance, and community structure of a leaf litter amphibian assemblage from globally important miombo-mopane woodlands characteristic of western Tanzania. We describe patterns of diversity across major habitat types and between different seasons from an annual pitfall-trapping campaign. We recorded 28 species of amphibians, which is significantly higher than existing richness estimates for other miombo woodland sites elsewhere in sub-Saharan Africa. We found that cultivation of native habitat reduces frog diversity, a conclusion that has important implications in light of the rapid conversion of miombo woodland for agriculture and fuel-wood across much of southern and central Africa. Many species showed strongly ansynchronized patterns of seasonality in relative abundance, which has significant implications for the establishment of successful monitoring programs and biodiversity surveys. These conclusions emphasize the importance of stratified long-term sampling in biodiversity studies and demonstrate that superficial levels of sampling effort can lead to erroneous conclusions regarding patterns of diversity in amphibian communities. The relatively poor focus on herpetofaunal research in African miombo-mopane woodland is out of proportion to its ecological and conservation significance.

The functional significance of the extraordinary black and white stripes of zebras is still mysterious but now an active field of research. Four major hypotheses have been put forward: stripes are an antipredator defence operating through crypsis [1] or confusion of predators [2], are a means of reinforcing social bonds [3], are defence against ectoparasites [4] or are a means of cooling zebras [5]. Now, in the second multifactorial analysis of striping in zebras to date, Larison et al. [6] investigated the environmental factors that explain geographical variation in striping within a single species, the plains zebra ( Equus quagga or Equus burchellii ). They matched variation in striping patterns at 16 sites across its geographical range to a suite of environmental variables as well as tsetse fly (glossinid) distribution and lion ( Panthera leo ) presence. They found that greater intensities of intraspecific striping were associated with warmer temperatures and high precipitation. Last year we published a similar but phylogenetically controlled analysis using all seven species of equids, namely the three striped zebra species, the African wild ass ( Equus africanus ) which has leg stripes but no body stripes, and the unstriped species of equids ( E. hemionus, E. kiang, E. ferus przewalski ), and 20 of their subspecies, and compared several aspects of the four hypotheses [7]. These were camouflage in woodlands, antipredator defence against both lions and spotted hyaenas ( Crocuta crocuta ), social interactions, tsetse fly distribution, tabanid distribution using both temperature and humidity ranges as a proxy for abundance, and temperature isoclines to assess the cooling hypothesis. First we ran univariate tests on individual factors to identify the hypotheses with the strongest predictive ability, then subsequently used AICc model selection procedures to pit the most promising predictors against each other—a …

Surrogate concepts are used in all sub-disciplines of environmental science. However, controversy remains regarding the extent to which surrogates are useful for resolving environmental problems. Here, we argue that conflicts about the utility of surrogates (and the related concepts of indicators and proxies) often reflect context-specific differences in trade-offs between measurement accuracy and practical constraints. By examining different approaches for selecting and applying surrogates, we identify five trade-offs that correspond to key points of contention in the application of surrogates. We then present an 8-step Adaptive Surrogacy Framework that incorporates cross-disciplinary perspectives from a wide spectrum of the environmental sciences, aiming to unify surrogate concepts across disciplines and applications. Our synthesis of the science of surrogates is intended as a first step towards fully leveraging knowledge accumulated across disciplines, thus consolidating lessons learned so that they may be accessible to all those operating in different fields, yet facing similar hurdles.

Functionalist approaches to teaching can be used to great effect in the study of teaching in both human societies and nonhuman species.

Mammalian carnivores are unusual because their primary competitors for food are often their primary predators. This relationship is most evident at persistent kills where dominant competitors are attracted to both the carcass (as a free meal) and to the killers (as potential prey). Cheetahs (Acinonyx jubatus) are frequent victims of kleptoparasitism, and cubs, and sometimes adults, are killed by lions (Panthera leo) or spotted hyenas (Crocuta crocuta). Between 1980 and 2002, we observed 639 kills made by cheetahs in Serengeti National Park, Tanzania. These kills were often visited by scavengers, including relatively innocuous species such as vultures and jackals and potentially dangerous species, like spotted hyenas and lions. We used cheetah behavior at kills to test a number of predictions about how cheetahs should minimize risk at kill sites given they face an increased risk of predation of themselves or their cubs. In particular, we examined the propensity of cheetahs of different age/sex classes to hide carcasses after making a kill, vigilance at kills, and the delay in leaving after finishing feeding with respect to ecological factors and scavenger presence. The behavior of single females at kills did not suggest that they were trying to avoid being killed, but the behavior of males, often found in groups, was in line with this hypothesis. In contrast, the behavior of mother cheetahs at kills appeared to be influenced greatly by the risk of cubs being killed. Our results suggest that cheetahs use several behavioral counterstrategies to avoid interspecific predation of self or cubs.

We collated aerial census data collected during the late 1980s to early 2000s for large herbivore populations in eight large census zones in Tanzania. Of the ungulate populations that showed significant changes in densities at the start versus end of this decade, most declined; very few populations increased significantly. Thomson's gazelle, Grant's gazelle, hartebeest, reedbuck, roan antelope, sable antelope, warthog and zebra, for example, declined in over 50% of the zones where they were surveyed. Interestingly, small-bodied species fared particularly poorly in many census zones, whereas elephant and giraffe generally fared well across the country. Most populations of all herbivores declined in some portions of the country (e.g. Burigi-Biharamulo, Katavi, Greater Ruaha and Tarangire census zones). These surveys suggest that, even in a country renowned for its protected areas and conservation commitment, some large herbivore populations need more conservation attention in order to remain stable. Resume Nous avons rassemble les donnees recoltees entre la fin des annees 1980 et le debut des annees 2000 lors de recensements des populations de grands herbivores dans huit vastes zones de Tanzanie. La plupart des populations d'ongules qui presentaient des changements de densite significatifs entre le debut et la fin de ces recensements avaient diminue; tres peu avaient augmente significativement. La gazelle de Thomson, la gazelle de Grant, le bubale, le cobe des roseaux, l'antilope rouanne, l'antilope sable, le phacochere et le zebre, par exemple, avaient decline dans plusieurs zones. Il est interessant de remarquer que les especes de petite taille avaient des resultats plutot mediocres dans de nombreuses zones de recensement alors que les elephants et les girafes s'en sortaient bien dans tout le pays. La plupart des populations de tous les herbivores ont baisse dans certaines parties du pays (ex. les zones de recensement de Burigi-Biharamulo, Katavi, le Grand Ruaha et Tarangire). Ces etudes montrent que, meme dans un pays renomme pour son engagement envers ses aires protegees et la conservation, certaines populations de grands herbivores ont besoin d'une attention de conservation plus grande pour rester stables.

We sampled butterflies in six different habitat types in and around Katavi National Park, a remote reserve consisting primarily of miombo woodland and seasonal lakes in western Tanzania. Blendon traps set for 531 trap days and 143 h of butterfly netting at 35 sites yielded 186 species from five families over a 4-month period during the wet season. Eight of these species constituted possible range extensions. Butterfly abundance and species richness were low in cultivated habitats but high in open riverine habitats; many butterfly species were found only in seasonally flooded grassland. This study constitutes the first butterfly species inventory from this poorly-known national park, shows that protection of dry season water sources provides an important conservation service for invertebrates as well as large mammals, and that increased cultivation outside miombo parks can reduce local butterfly diversity. Resume Nous avons preleve des echantillons de papillons dans six types d'habitat differents dans, et autour du Parc National de Katavi, une reserve reculee composee principalement de foret de Miombo et de lacs saisonniers, dans l'ouest de la Tanzanie. Des pieges Blendon installes 531 jours/piege, et 143 heures de recolte au filet a 35 sites ont permis de recolter 186 especes appartenant a cinq familles, pendant quatre mois de saison des pluies. Huit de ces especes constituaient des extensions possibles de la repartition. L'abondance de papillons et la richesse en especes etaient faibles dans les habitats cultives, mais elevees dans les habitats riverains ouverts. De nombreuses especes ne se trouvaient que dans les prairies inondees de facon saisonniere. Cette etude constitue le premier inventaire des papillons de ce parc national mal connu; elle montre que la protection des sources d'eau de saison seche est un atout important pour la conservation des invertebres comme des grands mammiferes, et que la culture a l'exterieur des parcs a Miombo peut reduire la diversite locale des papillons.

Pterocarpus angolensis (Fabaceae) is a leguminous tree species of the miombo region of sub-Saharan Africa that is highly prized for its wood value. We use both experimental exposure to fire, as well as classification of field burned seeds, to predict germination rates in seeds from both husked and unhusked fruits. We find that seed germination and seed persistence in unhusked fruits are maximized by moderate exposure to fire. Germinating seeds had heavier fruit and seeds than those that did not. Finally, seeds without husks persisted in the soil yet continued to germinate even after 18 months in wet soil, indicating potentially long soil longevity. Using these results, we support an intermediate fire exposure model wherein repeated moderate exposure to fire enhances the capability of seeds to emerge from fruits. Seeds from unburned and unhusked fruits were never observed to germinate and had poorer soil longevity than those exposed to moderate fire. Similarly, extreme exposure to fire resulted in poor seed germination rates, often as a consequence of direct fire mortality of seeds. We suggest that early burning resulting in cool fires may augment germination and recruitment in wild populations.

Fully protected areas such as National Parks are often assumed to be the best way to conserve plant diversity and maintain intact forest composition and structure. To evaluate this assertion, we sampled trees in areas with four different levels of protection: a National Park, where the protection level is very high, a Game Controlled Area which allows tourist hunting of big game animals, a Forest Reserve which allows selective harvest of trees, and an Open Area where human populations have unrestricted access to forest resources. All four land management areas had healthy size-class distributions with greater numbers of juvenile trees (2–10 cm DBH) than adults. Surprisingly, mean stem density of trees was highest (947 stems ha −1 ) in the Game Controlled Area but was lowest (635 stems ha −1 ) in the National Park. The former had the highest basal area value (24 m 2 ha −1 ) while the human-inhabited Open Area had the lowest (11 m 2 ha −1 ). Species richness in the Forest Reserve and Game Controlled Area was significantly higher than in the other areas. The total number of plots with unique species not found anywhere else was lowest in the National. Our measures of forest structure and composition therefore show that fully protected National Parks do not necessarily conserve the greatest diversity of tree species or unique species, indicating that a suite of different types of protection strategies may be the key to conservation of trees in these African dry tropical forests.

In conservation biology, researchers often want to study the reasons why an endangered population is faring poorly but are unable to study it directly for logistical or political reasons. Instead they study a species that substitutes for the one of concern in the hope that it will cast light on the conservation problem. Here we outline the assumptions underlying this approach. Substitutes can be different populations or species and may be chosen because they are similar biologically to the target or representatives of a constellation of species of which the target is one. They also may be used to develop a predictive model to which the conservation target can be related. For substitutes to be appropriate, they should share the same key ecological or behavioral traits that make the target sensitive to environmental disturbance and the relationship between population vital rates and level of disturbance should match that of the target. These conditions are unlikely to pertain in most circumstances and the use of substitute species to predict endangered populations' responses to disturbance is questionable.

Pterocarpus angolensis is a hardwood species subject to heavy exploitation throughout miombo woodlands of south-central Africa. Rates of natural recruitment measured in western Tanzania were found to be low, with only a third of parent trees generating any seedlings despite considerable seed production. Although heavily protected areas supported large parent trees, these adults had very few seedlings of >5 cm DBH nearby, possibly suggesting mortality caused by high densities of browsing ungulates. Outside these well protected areas, cutting has removed most large trees and remaining adults are small producing relatively few seeds. Factors affecting recruitment include location and elevation perhaps indicative of higher precipitation, whereas short grass and reduced parent canopy cover are associated with more seedlings suggesting competition for light. Given these recruitment rates, the prognosis for sustainable exploitation of P. angolensis looks bleak.

Despite a growing interest among ethologists in applying their work to conservation, ethologists have yet to convince conservation biologists that the study of animal behaviour is of much use to conservation. In part this is because there are few empirical examples to support their claim. Here I show that mammal species subject to covert human hunting pressure are significantly more wary of observers than species that are less heavily exploited. Thus, an easily observed aspect of behaviour provides an indicator of exploitation that would otherwise be difficult for managers to measure.

We used comparative data to test functional hypotheses for 17 antipredator behaviour patterns in artiodactyls. We examined the literature for hypotheses about auditory and visual signals, defensive behaviour and group-related antipredator behaviour in this taxon and derived a series of predictions for each hypothesis. Next, we documented occurrences of these behaviour patterns and morphological, ecological and behavioural variables for 200 species and coded them in binary format. We then pitted presence of an antipredator behaviour against presence of an independent variable for cervids, bovids and all artiodactyls together using nonparametric tests. Finally, we reanalysed the data using Maddison's (1990, Evolution , 44 , 539–557) concentrated-changes tests and a consensus molecular and taxonomic phylogeny. We found evidence that snorting is both a warning signal to conspecifics and a pursuit-deterrent signal, lack of evidence that whistling alerts conspecifics and indications that foot stamping is a visual signal to warn group members. Evidence suggested that tail flagging was a signal to both conspecifics and predators, that bounding, leaping and stotting were used both as a signal and to clear obstacles and that prancing functioned similarly to foot stamping. Analyses of tail flicking, zigzagging and tacking were equivocal. We confirmed that inspection occurs in large groups, freezing enhances crypticity, and species seeking refuge in cliffs tend to be small. Entering water and attacks on predators had few correlates. Finally, group living, a putative antipredator adaptation, was associated with large body size and species living in open habitats, confirming Jarman's (1974, Behaviour , 48 , 215–267) classic hypothesis. Bunching and group attack apparently deter predators. Despite limitations, comparative and systematic analyses can bolster adaptive hypotheses and raise new functional explanations for antipredator behaviour patterns in general.

Flagship species are charismatic species that serve as a symbol and rallying point to stimulate conservation awareness and action but are often used synonymously as de facto umbrella species to delineate reserve boundaries. We tested the extent to which the presence of a flagship species would protect other ‘background species’ at the local scale at which practical decisions about small reserves are often made. Using long term sightings, we identified four 1 km2 sites that are frequently visited by jaguars and by tapirs (flagship species), and by white-lipped peccaries and spider monkeys (non-flagship species) in neotropical rainforest in Belize. We then made inventories of five vertebrate taxonomic groups at each site. We found no consistent differences in species richness or abundances of frogs, phyllostomid bats, terrestrial mammals, scansorial mammals or birds across the four sites, except that frog diversity and abundance was higher close to a river at the flagship site where tapirs were found. Since these classic Latin American flagship species fail to encompass particularly high numbers or abundances of vertebrate species at a local scale, they appear to be a poor conservation tool when co-opted as umbrella species for delineating the location of very small reserves in the neotropics.

We examined environmental and social factors affecting reproductive success across a 20-year data set of individually known cheetahs on the Serengeti Plains of Tanzania. Because cheetahs are seen infrequently and are not amenable to mark–recapture techniques, we devised a model to estimate time of death for individuals that disappeared from our records. We found that males had markedly lower survival than females. Recruitment was negatively affected by rainfall but positively affected by numbers of Thomson’s gazelles, the cheetahs’ chief prey. There was a negative association between recruitment and numbers of lions, demonstrating that the high rates of predation observed in previous studies have implications for the dynamics of cheetah populations. Recruitment was related to mother’s age, peaking when she reached 6–7 years. Sociality affected survival in two ways. First, adolescents living in temporary sibling groups had higher survival than singletons, particularly males with sisters. Second, adult males living in coalitions had higher survival than singletons in periods when other coalitions were numerous, yet they had lower survival when other coalitions were rare. These results corroborate observations of enhanced prey capture by female adolescents and antipredator benefits for adolescents in groups, as well as competitive advantages for adult males in groups. Furthermore, our findings stress the importance of interactions between environmental and social factors in affecting reproductive success in mammals. Key words: Acinonyx jubatus, age, cheetahs, group living, predator avoidance, predator–prey relationships, reproductive success, sociality. [Behav Ecol 15:11–22 (2004)]

Herein lies the story of Craig Packer's struggle to save lions in the wild. We learn the names and personalities of politicians and decision makers on the international stage and in Tanzania. We gain insights about the hunting industry, especially officials in the Wildlife Division, which oversees hunting in Tanzania, about Safari Club International, about corruption in Tanzania, and about the author himself. There is a lot of science here, too, concerning the function of lion manes, how field experiments are conducted, and why lions become man-eaters.

To examine factors that might influence how people subscribe to different reasons for conserving biological diversity, we modified Ehrenfeld's [American Scientist 64 (1976) 660] classic reasons for conserving species and habitats into consumption, tourism, medicine, science. education, environmental baselines, ecosystem services, intrinsic value, and added another, human cultural heritage. We then explored the opinions of undergraduates enrolled in a classic conservation biology course, or a people and conservation course, about these nine arguments, using a 27-statement questionnaire. By matching responses made before and after each course, we found that students, in general. became more committed to using most of Ehrenfeld's arguments but that this was highly contingent on which conservation course that they had taken. None became committed to the argument that linked wildlife conservation to human culture. however. Course and grade that students attained influenced the extent to which students were sympathetic to different arguments but gender had no effect. These findings show that the type of conservation knowledge imparted to students makes them differentially sympathetic to many of the arguments used to advocate wildlife conservation. (C) 2003 Elsevier Ltd. All rights reserved.

Lagomorph pelage coloration was matched to habitat type, geographical region, altitude and behaviour to explore the adaptive significance of coloration patterns in this little-studied order of mammals. Analyses were conducted with and without taking phylogeny into account. The former analyses were based on a weighted, phylogenetic supertree for all extant species of lagomorphs that we constructed using morphological and molecular data from 146 papers in the literature. Although our analyses represent an initial, somewhat crude investigation, several clear trends are evident. First, overall body coloration across lagomorphs tends to match the background as shown for pale and red coloration and perhaps seasonal pelage change. The case for countershading being a method of concealment is far less strong. Second, ear tips appear to have a communicative role since they are conspicuous in many different habitats. Third, hypotheses for tail tips having a communicative role, for extremities being dark for physiological reasons, and for Gloger's rule received only partial support.

Umbrella species are ‘species with large area requirements, which if given sufficient protected habitat area, will bring many other species under protection’. Historically, umbrella species were employed to delineate specific reserve boundaries but are now used in two senses: (1) as aids to identifying areas of species richness at a large geographic scale; (2) as a means of encompassing populations of co-occuring species at a local scale. In the second sense, there is a dilemma as to whether to maximize the number or viability of background populations; the umbrella population itself needs to be viable as well. Determining population viability is sufficiently onerous that it could damage the use of umbrella species as a conservation shortcut. The effectiveness of using the umbrella-species concept at a local scale was investigated in the real world by examining reserves in East Africa that were gazetted some 50 years ago using large mammals as umbrella species. Populations of these species are still numerous in most protected areas although a few have declined. Populations of other, background species have in general been well protected inside reserves; for those populations that have declined, the causes are unlikely to have been averted if reserves had been set up using other conservation tools. Outside one reserve, Katavi National Park in Tanzania, background populations of edible ungulates and small carnivores are lower than inside the reserve but small rodent and insectivore abundance is higher. While we cannot compare East African reserves to others not gazetted using umbrella species, the historical record in this region suggests that umbrella species have been an effective conservation shortcut perhaps because most reserves were initially large and could encompass substantial populations of background species. It is therefore premature to discard the local-scale umbrella-species concept despite its conceptual difficulties.

Tree regeneration and understory response to selective cutting of Pterocarpus angolensis DC, and Sterculia quinqueloba Sim, was measured outside Katavi National Park, Tanzania. Contrary to expectations, a selective harvest had no effect on tree recruitment for either species in this miombo woodland. In unlogged plots along transects taken at increasing distance from a main road, the stand densities of young trees declined away from the road. Since anthropogenic activity along the road results in a high fire frequency but low native ungulate densities, the increased rate of tree regeneration near the road may result from either reduced grazing and browsing pressure by native ungulates, or reduced fire intensity and severity along roads. These effects appear to mask any possible effect of selective harvest on tree recruitment. Currently, there is no evidence of compensatory recruitment of trees of any species into the canopy to replace logged trees and this will lead to a gradual thinning in overstory stand density. Resume Introduction

The general importance of interspecific competition as an ecological factor for carnivores is unknown and its conservation significance may have been inflated by intensive research conducted on a few vulnerable species. We therefore examined the potential for interspecific competition across carnivores on one continent, Africa, by calculating, for each of 70 carnivore species, the number of other carnivore species that overlapped it in geographic range, habitat, and diet, and that could potentially kill the species in question. The average carnivore in Africa shares some of its geographic range and habitat with 26 other species suggesting competition could be pervasive. More specifically, carnivores may have to share food resources with 22 other carnivore species, on average, although the potential for food stealing is far lower. The average African carnivore may be vulnerable to predation by 15 other species although it is unlikely to be eaten by other carnivores. These analyses indicate that exploitative competition and interspecific killing are of potential widespread importance for a large number of carnivores in Africa, rather than being restricted to a few selected carnivores highlighted in the current literature.

To test the generality of adaptive explanations for coat coloration in even-toed ungulates, we examined the literature for hypotheses that have been proposed for color patterns exhibited by this taxon, and we derived a series of predictions from each hypothesis. Next, we collected information on the color, behavioral, and ecological characteristics of 200 species of even-toed ungulates and coded this in binary format. We then applied chi-square or Fisher’s Exact probability tests that pitted presence of a color trait against presence of an ecological or behavioral variable for cervids, bovids, and all artiodactyls. Finally, we reanalyzed the data by using concentrated-changes tests and a composite molecular and taxonomic phylogeny. Hinging our findings on whether associations persisted after controlling for shared ancestry, we found strong support for hypotheses suggesting even-toed ungulates turn lighter in winter to aid in concealment or perhaps thermoregulation, striped coats in adults and spotted pelage in young act as camouflage, side bands and dark faces assist in communication, and dark pelage coloration is most common in species living in the tropics (Gloger’s rule). Whereas white faces, dark legs, white legs, dark tails, and white tails did not appear to assist in communication alone, legs and tails that were either dark or white (i.e., conspicuous) did seem to be linked with communication. There was moderate support for hypotheses that countershading aids concealment, that white faces are a thermoregulatory device, and that white rumps are used in intraspecific communication. There was weak support for spots in adults and stripes in young providing camouflage and for dark leg markings being a form of disruptive coloration. We found little or no evidence that overall coat color serves as background matching, that side bands are disruptive coloration devices, or that white rumps help in thermoregulation. Concealment appears the principal force driving the evolution of coloration in ungulates with communication, and then thermoregulation, playing less of a role. Key words: bovids, cervids, communication, concealment, countershading, disruptive coloration, pattern blending, phylogeny, thermoregulation, ungulates. [Behav Ecol 14:823–840 (2003)]