Late Dry Season Research Articles

Towards meaningful monitoring: A case study of a threatened rodent

AbstractDetecting trends in species’ distribution and abundance are essential for conserving threatened species, and depend upon effective monitoring programmes. Despite this, monitoring programmes are often designed without explicit consideration of their ability to deliver the information required by managers, such as their power to detect population changes. Here, we demonstrate the use of existing data to support the design of monitoring programmes aimed at detecting declines in species occupancy. We used single‐season occupancy models and baseline data to gain information on variables affecting the occupancy and detectability of the threatened brush‐tailed rabbit‐ratConilurus penicillatus(Gould 1842) on the Tiwi Islands, Australia. This information was then used to estimate the survey effort required to achieve sufficient power to detect changes in occupancy of different magnitudes. We found that occupancy varied spatially, driven primarily by habitat (canopy height and cover, distance to water) and fire history across the landscape. Detectability varied strongly among seasons, and was three times higher in the late dry season (July–September), compared to the early dry season (April–June). Evaluation of three monitoring scenarios showed that conducting surveys at times when detectability is highest can lead to a substantial improvement in our ability to detect declines, thus reducing the survey effort and costs. Our study highlights the need for careful consideration of survey design related to the ecology of a species, as it can lead to substantial cost savings and improved insight into species population change via monitoring.

Characteristics of Human-Wildlife Conflicts in Kenya: Examples of Tsavo and Maasai Mara Regions

Human-wildlife conflict (HWC) is a widespread and persistent challenge to conservation. However, relatively few studies have thus far examined long-term monitoring data to quantify how the type, and severity of HWC varies across species, seasons, years and ecosystems. Here, we examine human-wildlife conflicts in Tsavo and Maasai Mara, two premier wildlife conservation areas in Kenya. Using Kenya Wildlife Service (KWS) data (2001-2016), we show that both the type and severity of conflicts vary among species such that the African elephant (Loxodonta africana), is the leading conflict species in both the Tsavo (64.3%, n= 30664) and Mara (47.0%, n=12487) ecosystems. The next four most notorious conflict animals, in decreasing order, are nonhuman primates (Tsavo 11.4%, n=3502; Mara 11.8%, n=1473), African buffalo (Syncerus caffer, Tsavo 5.5%, n=1676; Mara 11.3%, n=1410), lion (Panthera leo,Tsavo 3.6%, n=1107; Mara 3.3%, n=416) and spotted hyena (Crocuta crocuta, Tsavo 2.4%, n=744; Mara 5.8%, n=729). We group the observed conflict incidences (n= 43,151) into four major conflict types, including crop raiding, the most common conflict type, followed by human and livestock attacks and property damage. The severity of conflicts also varies markedly seasonally and inter-annually. Crop raiding peaks in May-July, during and at the end of the wet season when crops are maturing but is lowest in November during the late dry season and beginning of the early rains. Attacks on humans and livestock increased more than other conflict types in both Tsavo (from 2001) and Mara (from 2013). Relatively fewer people in Mara (7.2%, n=901) than in Tsavo (38.2%, n = 11714) felt threatened by wildlife, suggesting that the Maasai people are more tolerant of wildlife. Minimizing HWC is tightly linked to successfully resolving the broader conservation challenges, including enhancing ecosystem connectivity, community engagement and conservation benefits to communities.

Patterns of flow, leaf litter and shredder abundance in a tropical stream

The seasonal dynamics of leaf litter and associated consumers (“shredders”) in tropical streams are not well documented. We investigated the occurrence of litter (density and age composition) and shredders through late dry, wet and early dry seasons in an Australian rainforest stream. Leaf litter packs of varying density and leaf age covered most of the stream bed in the late dry season, but a one-in-one-year flood removed a substantial proportion of the sparse packs and much of the intermediate-aged litter, with green litter becoming more prevalent. Shredder abundances declined accordingly, but recovery was rapid, demonstrating substantial resilience to the disturbance. In a 36-day field experiment using fine- and coarse-mesh bags, green litter was decomposed more rapidly than intermediate and aged litter by both microbes and shredders, an unexpected and important result, given the abundance of green litter in the study stream. The resilience of shredders to moderate flood, their ability to process green leaves and their continued presence across seasons contribute to seasonal consistency in detrital-based food webs in the study stream except, perhaps, after extreme floods. This study demonstrates the need to consider the temporal changes in litter composition and decomposition in determining the nature of trophic processes in streams.

Atmospheric Dust, Early Cases, and Localized Meningitis Epidemics in the African Meningitis Belt: An Analysis Using High Spatial Resolution Data.

Background:Bacterial meningitis causes a high burden of disease in the African meningitis belt, with regular seasonal hyperendemicity and sporadic short, but intense, localized epidemics during the late dry season occurring at a small spatial scale [i.e., below the district level, in individual health centers (HCs)]. In addition, epidemic waves with larger geographic extent occur every 7–10 y. Although atmospheric dust load is thought to be an essential factor for hyperendemicity, its role for localized epidemics remains hypothetic.Objectives:Our goal was to evaluate the association of localized meningitis epidemics in HC catchment areas with the dust load and the occurrence of cases in the same population early in the dry season.Methods:We compiled weekly reported cases of suspected bacterial meningitis at the HC resolution for 14 districts of Burkina Faso for the period 2004–2014. Using logistic regression, we evaluated the association of epidemic HC-weeks with atmospheric dust [approximated by the aerosol optical thickness (AOT) satellite product] and with the observation of early meningitis cases during October–December.Results:Although AOT was strongly associated with epidemic HC-weeks in crude analyses across all HC-weeks during the meningitis season [odds ratio (OR) ; 95% CI: 4.90, 9.50], the association was no longer apparent when controlling for calendar week (OR ; 95% CI: 0.60, 1.50). The number of early meningitis cases reported during October–December was associated with epidemic HC-weeks in the same HC catchment area during January–May of the following year (OR for each additional early case ; 95% CI: 1.06, 1.21).Conclusions:Spatial variations of atmospheric dust load do not seem to be a factor in the occurrence of localized meningitis epidemics, and the factor triggering them remains to be identified. The pathophysiological mechanism linking early cases to localized epidemics is not understood, but their occurrence and number of early cases could be an indicator for epidemic risk. https://doi.org/10.1289/EHP2752

Season affects fire behavior in annually burned humid savanna of West Africa

BackgroundFire is important for the maintenance of African savanna ecosystems, particularly humid savanna. Despite the importance of fire behavior to our understanding of fire’s ecological effects, few studies have documented fire behavior and its determinants in humid West African savannas and, in particular, whether fire behavior depends on season of the year. We analyzed fire behavior in the Guinean savanna of Lamto (Ivory Coast) during a 4-year field experiment. The fire regimes tested consisted of three different burning seasons: early-season fire, mid-season fire, and late-season fire. Nine 0.5 ha plots were burned annually to determine the rate of spread and fire intensity. Fuel characteristics and weather conditions were measured to assess their impact on fire behavior.ResultsUnderstory grass height, total fresh fuel load, and moisture content had greater values in early-season fire than in mid-season and late-season fire. The rate of spread and intensity of both mid-season fire (0.14 ± 0.03 m s−1 and 3920 ± 740 kW m−1, respectively) and of late-season fire (0.12 ± 0.02 m s−1 and 3134 ± 482 kW m−1, respectively) were significantly greater than those of early-season fire (0.04 ± 0.01 m s−1 and 1416 ± 252 kW m−1, respectively). The best predictors of fire behavior were fuel moisture content and air humidity; these two explanatory variables were the sole significant predictors for fire intensity, rate of fire spread, and flame height.ConclusionsGiven that there is no difference between intensity of mid-season and late-season fire, we suggest that the generally reported higher impact of late-season fire on trees in the West African humid savannas is due not to fire intensity per se, but rather to a more sensitive phenological stage of trees (e.g., leafless in mid-season), and to a longer time of exposure to lethal temperatures (> 60 °C) in the late dry season. These data provide important insights into fire behavior in the Guinean savanna−forest mosaic ecoregion, informing fire management.

Incentivising fire management in Pindan (Acacia shrubland): A proposed fuel type for Australia's Savanna burning greenhouse gas emissions abatement methodology

SummaryThe Australian Government has sanctioned development of greenhouse gas emissions (GHG) abatement methodologies to meet international emissions reduction obligations. Savanna burning emissions abatement methodologies have been available since 2012, and there are currently 72 registered projects covering approximately 32 million ha. Abatement to date has exceeded 4 million tonnes of carbon dioxide equivalent (CO2‐e) principally through the application of low intensity early dry season fire management to reduce the amount of biomass combusted in higher intensity late dry season (LDS) fires. Savanna burning projects can only be conducted on areas with eligible fire‐prone vegetation fuel types where implementing the improved fire management regime is considered ecologically appropriate. This study assesses the suitability of including tall Acacia shrublands (‘Pindan’) as a new eligible fuel type. These shrublands make up 12% (~2 million ha) of the Kimberley region, Western Australia, where, on average, 32% is fire affected annually, mostly in the LDS. A standard assessment protocol was applied to describe vegetation fuel type structural and pyrolysis characteristics. We show that Pindan (i) can be identified and mapped as a unique tall Acacia shrubland vegetation fuel type, (ii) characterised by a significantly greater shrubby fuel load biomass, and (iii) the conservation status of which would benefit from imposition of strategic prescribed burning programme. Savanna burning projects in the Pindan fuel type could potentially abate up to 24.43 t.CO2‐e/km2 per year, generating significant income and employment opportunities for predominantly Indigenous land managers in the region.

Fuel load mapping in the Brazilian Cerrado in support of integrated fire management

The Brazilian Cerrado is considered to be the most species-rich savannah region in the world, covering ~2 million km2. Uncontrolled late season fires promote deforestation, produce greenhouse gases (~25% of Brazil's land-use related CO2 emissions between 2003 and 2005) and are a major threat to the conservation of biodiversity in protected areas. Governmental institutions therefore implemented early dry season (EDS) prescribed burnings as part of integrated fire management (IFM) in protected areas of the Cerrado, with the aim to reduce the area and severity of late dry season (LDS) fires. The planning and implementation of EDS prescribed burning is supported by satellite-based geo-information on fuel conditions, derived from Landsat 8 and Sentinel-2 data. The Mixture Tuned Matched Filtering algorithm was used to analyse the data, and the relationship between the resulting matched fractions (dry vegetation, green vegetation and soil) and in situ surface fuel samples was assessed. The linear regression of in situ data versus matched filter scores (MF scores) of dry vegetation showed an r2 of 0.81 (RMSE = 0.15) and in situ data versus MF scores of soil showed an r2 of 0.65 (RMSE = 0.38). To predict quantitative fuel load, a multiple linear regression analysis was carried out with MF scores of NPV and soil as predictors (adjusted r2 = 0.86; p < 0.001; standard error = 0.075). The fuel load maps were additionally evaluated by fire managers while planning EDS prescribed burning campaigns. The fuel load mapping approach has proven to be an effective tool for integrated fire management by improving the planning and implementation of prescribed burning, promoting pyrodiversity, prioritising fire suppression and evaluating fire management efforts to meet overall conservations goals. National and state level authorities have successfully institutionalized the approach and it was incorporated into IFM policies in Brazil.

Reproductive Ecology of Wrinkle-Lipped Free-Tailed Bats Chaerephon plicatus (Buchannan, 1800) in Relation to Guano Production in Cambodia

Wildlife populations in Southeast Asia are subject to increasing pressure from climate change, habitat loss and human disturbance. Cave-roosting bats are particularly vulnerable to all three factors. Because of the ecological services they provide, it is important to assess specific vulnerabilities to inform their conservation management. We evaluated the reproductive phenology and body condition of Chaerephon plicatus for 14 months in 2015–2016 and quantified guano harvesting at the largest colony in Cambodia in 2011–2016. As in Thailand and Myanmar, two annual breeding cycles were recorded, characterized as continuous bimodal polyoestry, with parturition primarily occurring in April and October. Significant declines occurred in body condition between the late wet season and the late dry season, suggesting that bats experience increasing energetic stress as the dry season progresses. Annual guano harvests increased over the study period but could not be used as a proxy for monitoring population size due to the loss of unknown amounts during the wet season and unquantified movements of bats between C. plicatus colonies in the region. We recommend studies to determine the scale and drivers of such movements and creation of sustainable guano harvesting and population monitoring initiatives to ensure the conservation of C. plicatus colonies in Cambodia.

Ectoparasite communities of small-bodied Malagasy primates: seasonal and socioecological influences on tick, mite and lice infestation of Microcebus murinus and M. ravelobensis in northwestern Madagascar

BackgroundEctoparasitic infections are of particular interest for endangered wildlife, as ectoparasites are potential vectors for inter- and intraspecific pathogen transmission and may be indicators to assess the health status of endangered populations. Here, ectoparasite dynamics in sympatric populations of two Malagasy mouse lemur species, Microcebus murinus and M. ravelobensis, were investigated over an 11-month period. Furthermore, the animals’ body mass was determined as an indicator of body condition, reflecting seasonal and environmental challenges. Living in sympatry, the two study species experience the same environmental conditions, but show distinct differences in socioecology: Microcebus murinus sleeps in tree holes, either solitarily (males) or sometimes in groups (females only), whereas M. ravelobensis sleeps in mixed-sex groups in more open vegetation.ResultsBoth mouse lemur species hosted ticks (Haemaphysalis sp.), lice (Lemurpediculus sp.) and mites (Trombiculidae gen. sp. and Laelaptidae gen. sp.). Host species, as well as temporal variations (month and year), were identified as the main factors influencing infestation. Tick infestation peaked in the late dry season and was significantly more often observed in M. murinus (P = 0.011), while lice infestation was more likely in M. ravelobensis (P < 0.001) and showed a continuous increase over the course of the dry season. Genetic analyses identified Lemurpediculus sp. infesting both mouse lemur species. Ticks morphologically conform to H. lemuris, but genetic analysis showed a clear differentiation of the specimens collected in this study, suggesting a potentially new tick species. Host body mass decreased from the early to the late dry season, indicating nutritional stress during this period, which may render individuals more susceptible to parasitic infections.ConclusionsSeasonal differences and species-specific variations in sleeping site ecology in terms of sleeping site type and sociality were determined as key factors influencing ectoparasitism in M. murinus and M. ravelobensis. This needs to be taken into account when evaluating ectoparasite infestations at a given time point. The detection of the same parasite species on two closely related and sympatric host species furthermore indicates a potential pathway for disease transmission, not only within but also between lemur species.

Microclimate in understories of a mango orchard and a degraded area in the Eastern Amazon

Changes in land use alter regional microclimate. This study compared the microclimate in understories of a mango orchard and a degraded area in the municipality of Salinópolis, in the northeast of the Brazilian State Pará, eastern Amazon. In both environments, the microclimate was monitored through collecting data on the following variables: maximum, minimum and average air temperature, air thermal amplitude and vapor pressure deficit. The microclimate was monitored daily during four seasons: early rainy season, late rainy season, early dry season and late dry season, between December 2015 and November 2016. Vegetation coverage was the most important factor to soften maximum and average air temperature in the understories. Lower values of meteorological variables were observed in the mango orchard understory, especially during late rainy season and late dry season, except for minimum air temperature, which was lower in the understory of the degraded area, especially during the late rainy season. The microclimate in the understory differed between both environments, and mango orchards may ameliorate the understory microclimate more efficiently than degraded areas; therefore, the mango orchard can be used as an alternative for the rehabilitation of degraded areas.

Arthropod pest complex and associated damage in field-grown tomato in Senegal

AbstractBiotic factors (including insect pests) constrain field-grown tomato production in Senegal. However, little information is available on the identity and life system of key pests. The objectives of this study were to: (i) update key pest records of field-grown tomato in the central vegetable-producing area along the northern coast of Senegal, known as the Niayes area; (ii) map their spatial and temporal incidence and (iii) understand insecticide use by growers to control the pests. A total of 98 tomato fields distributed in three zones along a north–south transect in the Niayes area were monitored over four crop cycles from 2012 to 2014. As expected, the tomato fruitworm Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) was the most destructive pest with an occurrence of 92% in sampled fields (90/98) and up to 38% damaged fruits in one field at the time of sampling. The proportion of damaged fruits did not differ among zones, but was significantly higher in the early dry season compared to the late dry season. The invasive tomato leafminer Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) was detected in 53% of sampled fields (52/98), mainly in the south of the Niayes area in the late dry season. Because of their ability to adapt to unstable environment and insecticides, this insect pest assemblage is a new challenge that farmers have to deal with while decreasing their use of broad-spectrum insecticides.

Use of resources and microplastic contamination throughout the life cycle of grunts (Haemulidae) in a tropical estuary

The distribution, feeding ecology and microplastic contamination were assessed in different ontogenetic phases of Haemulidae species inhabiting the Goiana Estuary, over a seasonal cycle. Pomadasys ramosus and Haemulopsis corvinaeformis are estuarine dependent species that use habitats with specific environmental conditions each season. Pomadasys ramosus was found in the upper and middle estuaries during the rainy season, when salinity showed the lowest values. Haemulopsis corvinaeformis was found in the lower estuary during the dry season, when salinity increased in the estuary. Juveniles of P. ramosus are zooplanktivores, feeding mainly on calanoid copepods. Sub-adults and adults are zoobenthivores, feeding on invertebrates associated to the bottom, mainly Polychaeta. Juveniles of H. corvinaeformis were not found in the main channel, but sub-adults and adults showed a zoobenthivore habit, feeding mainly on Anomalocardia flexuosa (Mollusca: Bivalvia). Dietary shifts along the life cycle and the spatio-temporal relationship between their distribution and the availability of microplastics along the estuary seem to have a strong influence in the ingestion of microfilaments. The highest average ingestion of microfilaments by P. ramosus coincided with the peak of ingestion of Polychaeta by sub-adults in the upper estuary during the late rainy season. For H. corvinaeformis the highest ingestion of microfilaments coincided with the peak of ingestion of A. flexuosa by adults in the lower estuary during the late dry season. Such contamination might be attributed to the time when these phases shifted to a more diverse diet and began to forage on benthic invertebrates. Research on microplastic contamination must consider species-specific behaviour, since the intake of microplastics is dependent on patterns of distribution and trophic guild within fish assemblages.

Flowering and Fruiting Phenology of Woody Trees in the Tropical-Seasonal Rainforest, Southwestern China

The reproductive phenology of tropical plants is potentially driven by a number of abiotic and biotic factors. However, it is still unclear as to which climatic factors and biotic interactions drive the reproductive phenology of woody trees in the tropical seasonal rainforest of Xishuangbanna region in Southwest China. We conducted observations on woody plants (including trees and shrubs) phenology between November 2004 and October 2007 at bi-weekly intervals in the one hectare permanent plot of tropical seasonal rainforest in Southwest China. A total of 357 individuals of 76 species (70 genera, 37 families),comprising of 59 (78%) woody trees and 17(22%) shrub species were observed. Our results demonstrate that flowering an fruiting frequencies show slight temporal variation between years. Flowering was significantly correlated with day-length, temperature and rainfall and fruiting was significantly correlated with rainfall and temperature. This finding indicates that woody tree reproductive phenology was primarily associated with temperature and rainfall and to a lesser extent with day-length. Reproductive phenology is also linked to seasonal patterns with flowering peaking in the late dry season and fruiting peaking in the late wet season. Moreover, reproductive phenology is also significantly associated with reproductive ecological guilds such as pollination types and dispersal modes. Community reproductive phenology is associated with climatic seasonality and biotic interactions. It also suggests that seasonal phenology patterns may play a fundamental role in community reproductive success in the tropical seasonal rainforest of Xishuangbanna region of South-west China.

Accuracy assessment of the latest generations of MODIS burned area products for mapping fire scars on a regional scale over Campos Amazônicos Savanna Enclave (Brazilian Amazon)

This article aims to analyze the accuracy of the latest versions of burned area (BA) products derived from Moderate Resolution Imaging Spectroradiometer (MODIS) series (MCD45A1 v051, MCD64A1 v051, and MCD64A1 v006), quantifying their progression in the annual/seasonal mapping of fire scars on a regional scale over tropical savanna environments. To this end, a validation was processed comparing each product with a BA reference covering the period of 2001 to 2016, available for one of the largest savanna vegetation enclaves located in the southern Brazilian Amazon, the Campos Amazonicos Savanna Enclave. Three indices derived from cross-tabulated error matrices were used in the comparison [commission error, omission error (Oe), and Dice coefficient]. Pareto boundaries were also computed to explore the influence of the spatial resolution of the MODIS products on detecting BAs. The overall assessment found a clear decrease in Oes, varying from 0.797 and 0.499 in the MCD45A1 v051 and MCD64A1 v051, respectively, to a value of 0.280 in the MCD64A1 v006. Improvements obtained with MCD64A1 v006 in the middle and late dry season periods were significant. The results validate the higher performance of MCD64A1 v006 and confirm it as a useful instrument for the regional mapping of BAs over tropical savanna areas.

Multiple uses of small reservoirs in crop-livestock agro-ecosystems of Volta basin: Implications for livestock management

Small reservoirs (SR) are structures that capture and store run-off from upstream catchment area for multiple uses including irrigation, fishing, livestock watering, domestic purpose and groundwater recharge. Though livestock watering is one of the major uses of small reservoirs in the Volta River basin of West Africa, there is limited information on how livestock management practices co-exist with other use of SRs. This study was carried out in a typical Sudano-Sahelian zone within the Volta basin in Burkina Faso, covering five reservoirs to 1) document multiple uses of the reservoirs with a focus on their utilization for livestock production. 2) identify proximate and long-term causes of livestock-related conflicts with regard to multiple uses of the water infrastructure and 3) explore strategies to manage the SR equitably for various uses. Adult males and boys accounted for at least 60% of the users of small reservoirs in our study. Livestock watering was done mainly by adult males. In addition to provision of water for livestock, small reservoirs also contributed to feed resources for animals by providing green forage (pasture grown on residual moisture) in the dry season which accounted for at least 5% of the total dry matter diet of cattle and small ruminant in late dry season. None of the 5 small reservoirs we studied was used for irrigated fodder production. Increased competitions over the use of small reservoirs, damage to irrigated crops by the animals, and increased number of livestock using the small reservoirs were ranked as the most important causes of conflict in the communities. Peaceful co-habitation of the use of the small reservoirs for irrigated vegetable production and livestock watering are essential for reduction of the incidence of conflict.

HUBUNGAN CUACA DAN KONSENTRASI PM10 (STUDI KASUS DI KOTA BANJARBARU)

This research’s aim was to identify the relationship between weather element with PM10 concentration in Banjarbaru both during normal condition and during smoke fog (smog) condition, to study the condition’s effect afflicts to weather element and PM10 concentration in ambient air and to determine standard quality concentration PM10’s threshold in ambient air during smog condition. The data were 10 minute PM10, humidity, and temperature and daily weather of 2015 that obtained from Banjarbaru Climatology Station meanwhile data of hotspot’s in South Kalimantan at 2015 was taken from MODIS satellite of Terra Aqua owned by NOAA. The 10 minutes data has been clustered using K-means method and the daily weather element relationship with PM10 concentration obtained based on regression analysis. When normal conditions, only temperature, and duration of irradiance were significantly has positively correlated with PM10 concentration, air humidity and significant rainfall are negatively correlated, the remain is not significant in effect, while during smog conditions; temperature, duration of irradiation, air pressure, average wind velocity, and maximum significant wind speed are positively correlated, air humidity, and rainfall significantly negatively correlated. Based on the results of K-means clustering analysis of PM10 concentration, there was higher humidity, higher temperature, and PM10 concentrations were below the standard quality threshold under normal conditions while in the case of smog conditions, lower humidity, lower temperature, and PM10 concentrations were above the quality standard threshold. PM10 concentration during smog condition reaches dangerous status/above the standard quality threshold before dry season until late dry season at 02.20 is in the dusk until 12.30 pm.

Fire management in the Brazilian savanna: First steps and the way forward

Abstract Several decades of frustrated attempts to prevent fires in the Brazilian Savanna (Cerrado) have led to deleterious ecological and management consequences. In 2014, the first Integrated Fire Management (IFM) programme was launched in three protected areas (PAs). The IFM programme considers local practices, ecological information, management options and aims to create landscape mosaics of different fire histories to conserve biodiversity, reduce the prevalence of late‐dry season (LDS) wildfires, protect fire‐sensitive vegetation and reduce conflicts between PA managers and local communities. The first 3 years of imposed fire management regimes led to 40%–57% reduction in LDS fires, improved dialogue between researchers, managers and local communities, generating fire management learning communities. Synthesis and applications. This Integrated Fire Management programme represents a major advance in Cerrado management and conservation, by actively managing fires and decreasing the proportion of areas burnt by late‐dry season wildfires. It can contribute to PAs’ management in the Cerrado and other South American fire‐prone ecosystems. Long‐term monitoring and research are essential to understand the ecological implications and to improve fire management practices.

Seasonal variation in the abundance and distribution of Anomalocardia flexuosa (Mollusca, Bivalvia, Veneridae) in an estuarine intertidal plain.

Spatial and temporal density and biomass of the infaunal mollusk Anomalocardia flexuosa (Linnaeus, 1767) evaluated a tidal plain at Goiana estuary (Northeast Brazil). Three hundred and sixty core samples were taken during an annual cycle from three intertidal habitats (A, B and C). Shell ranged from 2.20 to 28.48 mm (15.08 ± 4.08 mm). Recruitment occurred more intensely from January to March. Total (0–1,129 g m−2) differed seasons (rainy and dry), with highest values in the early rainy season (221.0 ± 231.44 g m−2); and lowest values in the late dry season (57.34 ± 97 g m−2). The lowest occurred during the late rainy (319 ± 259 ind m−2) and early dry (496 ± 607 ind m−2) seasons. Extreme environmental situations (e.g., river flow, salinity and water temperature) at the end of each season also affected density ranges (late dry: 0–5,798 ind m−2; late rainy: 0–1,170 ind m−2). A. flexuosa in the Goiana estuary presented a dominance of juvenile individuals (shell length < 20 mm), with high biomass main the recruitment period. Average shell length, density and biomass values suggest overfishing of the stock unit. A. flexuosa is an important food and income resource along its whole distribution range. The species was previously also known as Anomalocardia brasiliana (Gmelin, 1791).

Remote sensing of mangrove forest phenology and its environmental drivers

Mangrove forest phenology at the regional scale have been poorly investigated and its driving factors remain unclear. Multi-temporal remote sensing represents a key tool to investigate vegetation phenology, particularly in environments with limited accessibility and lack of in situ measurements. This paper presents the first characterisation of mangrove forest phenology from the Yucatan Peninsula, south east Mexico. We used 15-year time-series of four vegetation indices (EVI, NDVI, gNDVI and NDWI) derived from MODIS surface reflectance to estimate phenological parameters which were then compared with in situ climatic variables, salinity and litterfall. The Discrete Fourier Transform (DFT) was used to smooth the raw data and four phenological parameters were estimated: start of season (SOS), time of maximum greenness (Max Green), end of season (EOS) and length of season (LOS). Litterfall showed a distinct seasonal pattern with higher rates during the end of the dry season and during the wet season. Litterfall was positively correlated with temperature (r=0.88, p<0.01) and salinity (r=0.70, p<0.01). The results revealed that although mangroves are evergreen species the mangrove forest has clear greenness seasonality which is negatively correlated with litterfall and generally lagged behind maximum rainfall. The dates of phenological metrics varied depending on the choice of vegetation indices reflecting the sensitivity of each index to a particular aspect of vegetation growth. NDWI, an index associated to canopy water content and soil moisture had advanced dates of SOS, Max Green and EOS while gNDVI, an index primarily related to canopy chlorophyll content had delayed dates. SOS ranged between day of the year (DOY) 144 (late dry season) and DOY 220 (rainy season) while the EOS occurred between DOY 104 (mid-dry season) to DOY 160 (early rainy season). The length of the growing season ranged between 228 and 264days. Sites receiving a greater amount of rainfall between January and March showed an advanced SOS and Max Green. This phenological characterisation is useful to understand the mangrove forest dynamics at the landscape scale and to monitor the status of mangrove. In addition the results will serve as a baseline against which to compare future changes in mangrove phenology due to natural or anthropogenic causes.

The diet of open-habitat chimpanzees (Pan troglodytes schweinfurthii) in the Issa valley, western Tanzania

Comparative data on the diets of extant primates inform hypotheses about hominin resource use. Historically, data describing chimpanzee diets stem primarily from forest-dwelling communities, and we lack comparative data from chimpanzees that live in mosaic habitats that more closely resemble those reconstructed for Plio-Pleistocene hominins. We present data on the diet of a partially-habituated community of open habitat chimpanzees (Pan troglodytes schweinfurthii) from the Issa valley, western Tanzania, collected over a four-year period. Based mostly on macroscopic faecal analysis, Issa chimpanzees consumed a minimum of 69 plant species. There was no relationship between plant consumption and either fruit availability or feeding tree density; the most frequently consumed plant species were found in riverine forests, with woodland species consumed more frequently during the late dry season. We conclude by contextualising these findings with those of other open-habitat chimpanzee sites, and also by discussing how our results contribute towards reconstructions of early hominin exploitation of mosaic landscapes.