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Rainfall exerts a controlling influence on the availability and quality of vegetation and surface water for herbivores in African terrestrial ecosystems. We analyse temporal trends and variation in rainfall in the Maasai Mara ecosystem of East Africa and infer their implications for animal population and biodiversity dynamics. The data originated from 15 rain gauges in the Mara region (1965-2015) and one station in Narok Town (1913-2015), in Kenya's Narok County. This is the first comprehensive and most detailed analysis of changes in rainfall in the region of its kind. Our results do not support the current predictions of the International Panel of Climate Change (IPCC) of very likely increases of rainfall over parts of Eastern Africa. The dry season rainfall component increased during 1935-2015 but annual rainfall decreased during 1962-2015 in Narok Town. Monthly rainfall was more stable and higher in the Mara than in Narok Town, likely because the Mara lies closer to the high-precipitation areas along the shores of Lake Victoria. Predominantly deterministic and persistent inter-annual cycles and extremely stable seasonal rainfall oscillations characterize rainfall in the Mara and Narok regions. The frequency of severe droughts increased and floods intensified in the Mara but droughts became less frequent and less severe in Narok Town. The timings of extreme droughts and floods coincided with significant periodicity in rainfall oscillations, implicating strong influences of global atmospheric and oceanic circulation patterns on regional rainfall variability. These changing rainfall patterns have implications for animal population dynamics. The increase in dry season rainfall during 1935-2015 possibly counterbalanced the impacts of resource scarcity generated by the declining annual rainfall during 1965-2015 in Narok Town. However, the increasing rainfall extremes in the Mara can be expected to create conditions conducive to outbreaks of infectious animal diseases and reduced vegetation quality for herbivores, particularly when droughts and floods persist over multiple years. The more extreme wet season rainfall may also alter herbivore space use, including migration patterns.

In high temperate latitudes, ungulates generally give birth within a narrow time window when conditions are optimal for offspring survival in spring or early summer, and use changing photoperiod to time conceptions so as to anticipate these conditions. However, in low tropical latitudes day length variation is minimal, and rainfall variation makes the seasonal cycle less predictable. Nevertheless, several ungulate species retain narrow birth peaks under such conditions, while others show births spread quite widely through the year. We investigated how within-year and between-year variation in rainfall influenced the reproductive timing of four ungulate species showing these contrasting patterns in the Masai Mara region of Kenya. All four species exhibited birth peaks during the putative optimal period in the early wet season. For hartebeest and impala, the birth peak was diffuse and offspring were born throughout the year. In contrast, topi and warthog showed a narrow seasonal concentration of births, with conceptions suppressed once monthly rainfall fell below a threshold level. High rainfall in the previous season and high early rains in the current year enhanced survival into the juvenile stage for all the species except impala. Our findings reveal how rainfall variation affecting grass growth and hence herbivore nutrition can govern the reproductive phenology of ungulates in tropical latitudes where day length variation is minimal. The underlying mechanism seems to be the suppression of conceptions once nutritional gains become insufficient. Through responding proximally to within-year variation in rainfall, tropical savanna ungulates are less likely to be affected adversely by the consequences of global warming for vegetation phenology than northern ungulates showing more rigid photoperiodic control over reproductive timing.

The escalating illegal wildlife trade (IWT) is one of the most high-profile conservation challenges today. The crisis has attracted over US$350 million in donor and government funding in recent years, primarily directed at increased enforcement. There is growing recognition among practitioners and policy makers of the need to engage rural communities that neighbor or live with wildlife as key partners in tackling IWT. However, a framework to guide such community engagement is lacking. We developed a theory of change (ToC) to guide policy makers, donors, and practitioners in partnering with communities to combat IWT. We identified 4 pathways for community-level actions: strengthen disincentives for illegal behavior, increase incentives for wildlife stewardship, decrease costs of living with wildlife, and support livelihoods that are not related to wildlife. To succeed the pathways, all require strengthening of enabling conditions, including capacity building, and of governance. Our ToC serves to guide actions to tackle IWT and to inform the evaluation of policies. Moreover, it can be used to foster dialogue among IWT stakeholders, from local communities to governments and international donors, to develop a more effective, holistic, and sustainable community-based response to the IWT crisis. El creciente mercado ilegal de vida silvestre (MIVS) es uno de los obstáculos de más alto perfil para la conservación hoy en día. La crisis ha atraído más de US$350 millones en financiamiento por donadores y por el gobierno en los años recientes, principalmente dirigido a un aumento en la aplicación de la ley. Existe un reconocimiento creciente por parte de los practicantes y quienes hacen las políticas de la necesidad de hacer partícipes a las comunidades rurales que colindan o viven con la vida silvestre como compañeros clave para aplacar el MIVS. Sin embargo, se carece de un marco de trabajo para guiar dicha participación comunitaria. Desarrollamos una teoría de cambio (TdC) para guiar a quienes hacen las políticas, los donadores y los practicantes en el asociamiento con las comunidades para combatir el MIVS. Identificamos cuatro vías para las acciones a nivel comunitario: fortalecer los impedimentos para el comportamiento ilegal, incrementar los incentivos para la adopción de la vida silvestre, disminuir los costos de vivir con la vida silvestre y apoyar los sustentos que no están relacionados con la vida silvestre. Para tener éxito, todas las vías requieren fortalecer la activación de las condiciones, incluyendo la capacidad de construcción y de gobemanza. Nuestra TdC sirve para guiar las acciones que impidan el MIVS y para informar a la evaluación de las políticas. Además, puede utilizarse para fomentar el diálogo entre los accionistas del MIVS, desde las comunidades locales hasta los gobiernos y los donadores internacionales, para desarrollar una respuesta basada en la comunidad más efectiva, holística y sustentable a la crisis del MIVS.

Under a new category system based on the contribution of a PA to the conservation of biodiversity, Yellowstone National Park would be ranked (among other criteria) according to the objectives of maintaining self-sustaining populations of the endangered grizzly bear and wolf, and maintaining the natural dynamics of the entire guilds of native carnivores and herbivores. What attributes should be monitored to evaluate the effectiveness of a PA, given its objectives and its ability to counteract threats to achieve these objectives The revision of the IUCN category system will be a key topic at the 4th World Conservation Congress (October 2008) and at several other meetings on PAs organized in 2008 under the umbrella of the Convention on Biological Diversity. [...]the opportunity now presents itself to initiate the process of shifting the focus of the categories from management intent to conservation outcomes, thus making them fully operational tools in biodiversity conservation.

Ripple, W.J., Chapron, G., López-Bao, J.V., Durant, S.M., Macdonald, D.W., Lindsey, P.A., Bennett, E.L., Beschta, R.L., Bruskotter, J.T., Campos-Arceiz, A., Corlett, R.T., Darimont, C.T., Dickman, A.J., Dirzo, R., Dublin, H.T., Estes, J.A., Everatt, K.T., Galetti, M., Goswami, V.R., Hayward, M.W., Hedges, S., Hoffmann, M., Hunter, L.T.B., Kerley, G.I.H., Letnic, M., Levi, T., Maisels, F., Morrison, J.C., Nelson, M.P., Newsome, T.M., Painter, L., Pringle, R.M., Sandom, C.J., Terborgh, J., Treves, A., Van Valkenburgh, B., Vucetich, J.A., Wirsing, A.J., Wallach, A.D., Wolf, C., Woodroffe, R., Young, H., Zhang, L

Natality and recruitment govern animal population dynamics, but their responses to fluctuating resources, competition, predation, shifting habitat conditions, density feedback and diseases are poorly understood. To understand the influences of climatic and land use changes on population dynamics, we monitored monthly changes in births and juvenile recruitment in seven ungulate species for 15 years (1989-2003) in the Masai Mara Reserve of Kenya. Recruitment rates declined for all species but giraffe, likely due to habitat alteration and increasing vulnerability of animals associated with recurrent severe droughts, rising temperatures, unprecedentedly strong and prolonged El Niño-Southern Oscillation (ENSO) episodes, expansion of settlements, cultivation and human population growth in pastoral ranches adjoining the reserve. Birth rate showed strong and humped relationships with moving averages of monthly rainfall, whereas recruitment responded strongly to cumulative past rainfall. Increasing livestock incursions into the reserve depressed recruitment rate for quarter-grown topi. Expansion of pastoral settlements depressed birth rate in impala, zebra and giraffe. Frequent ENSO-related droughts caused progressive habitat desiccation and hence nutritional shortfalls for ungulates. The responses to climatic, land use and resource influences did not reflect body size, migratory or resident lifestyle, dietary guild, digestive physiology or degree of synchrony of breeding of the ungulate species.

We tested the hypothesis that ungulates time and synchronize births to match gestation and lactation with peak food availability and quality in seasonal environments, using ground counts of topi and warthog conducted over 174 months (July 1989-December 2003) in the Mara-Serengeti ecosystem. During this 15-year period, 2,725 newborn and 45,574 adult female topi and 933 newborn and 7,831 adult warthogs were recorded. Births were distinctly synchronized in both species but far less so than in ungulates in temperate regions. Extreme droughts delayed onset and reduced synchrony of calving and natality rates but high rainfall advanced onset and increased synchrony of calving and natality rates in both species, supporting the seasonality hypothesis. Annual shifts in birth peaks were significantly negatively correlated with the preceding wet season rainfall. Varying the timing and synchrony of births and natality rates are widespread but little understood adaptations of ungulates to climatic extremes. Climate change heightens the need for advancing this understanding because increasing frequency and severity of droughts is likely to decouple phenology of breeding in seasonally breeding ungulates from that in their food plants. Similar studies of African ungulates are either extremely rare or non-existent. New approaches to estimating the time of peak births and its confidence limits and the degree of synchrony of breeding are also presented.

Rainfall is a critical component of climate governing vegetation growth and production, forage availability and quality for herbivores. However, reliable rainfall measurements are not always available, making it necessary to predict rainfall values for particular locations through time. Predicting rainfall in space and time can be a complex and challenging task, especially where the rain gauge network is sparse and measurements are not recorded consistently for all rain gauges, leading to many missing values. Here, we develop a flexible Bayesian model for predicting rainfall in space and time and apply it to Narok County, situated in southwestern Kenya, using data collected at 23 rain gauges from 1965 to 2015. Narok County encompasses the Maasai Mara ecosystem, the northern-most section of the Mara–Serengeti ecosystem, famous for its diverse and abundant large mammal populations and spectacular migration of enormous herds of wildebeest, zebra and Thomson’s gazelle. The model incorporates geographical and meteorological predictor variables, including elevation, distance to Lake Victoria and minimum temperature. Salient features of our model are the use of non-stationary covariance structures and the facility to handle excess zeros and many missing observations. We assess the efficiency of the model by comparing it empirically with the established Gaussian process, Kriging, simple linear and Bayesian linear models. We use the model to predict total monthly rainfall and its standard error for all 5 × 5 km grid cells in Narok County for each year from 1965 to 2015. Using the Monte Carlo integration method, we estimate seasonal and annual rainfall and their standard errors for 29 sub-regions of Narok for each of the 51 years spanning 1965–2015. The non-stationary model can handle data from a sparse network of observations with many missing values and performs at least as well as or better than four established and widely used models on the Narok rainfall data set. The model produces rainfall predictions consistent with expectation and in good agreement with blended station and satellite rainfall values. The predictions are precise enough for most practical purposes. The model is very general and applicable to other variables besides rainfall.

A controversy at the 2016 IUCN World Conservation Congress on the topic of closing domestic ivory markets (the 007, or so-called James Bond, motion) has given rise to a debate on IUCN's value proposition. A cross-section of authors who are engaged in IUCN but not employed by the organization, and with diverse perspectives and opinions, here argue for the importance of safeguarding and strengthening the unique technical and convening roles of IUCN, providing examples of what has and has not worked. Recommendations for protecting and enhancing IUCN's contribution to global conservation debates and policy formulation are given.

Knowledge of mammalian diversity is still surprisingly disparate, both regionally and taxonomically. Here, we present a comprehensive assessment of the conservation status and distribution of the world's mammals. Data, compiled by 1700+ experts, cover all 5487 species, including marine mammals. Global macroecological patterns are very different for land and marine species but suggest common mechanisms driving diversity and endemism across systems. Compared with land species, threat levels are higher among marine mammals, driven by different processes (accidental mortality and pollution, rather than habitat loss), and are spatially distinct (peaking in northern oceans, rather than in Southeast Asia). Marine mammals are also disproportionately poorly known. These data are made freely available to support further scientific developments and conservation action.