MASTREE+: Time-series of plant reproductive effort from six continents.

Significant gaps remain in understanding the response of plant reproduction to environmental change. This is partly because measuring reproduction in long-lived plants requires direct observation over many years and such datasets have rarely been made publicly available. Here we introduce MASTREE+, a data set that collates reproductive time-series data from across the globe and makes these data freely available to the community. MASTREE+ includes 73,828 georeferenced observations of annual reproduction (e.g. seed and fruit counts) in perennial plant populations worldwide. These observations consist of 5971 population-level time-series from 974 species in 66 countries. The mean and median time-series length is 12.4 and 10 years respectively, and the data set includes 1122 series that extend over at least two decades (≥20 years of observations). For a subset of well-studied species, MASTREE+ includes extensive replication of time-series across geographical and climatic gradients. Here we describe the open-access data set, available as a.csv file, and we introduce an associated web-based app for data exploration. MASTREE+ will provide the basis for improved understanding of the response of long-lived plant reproduction to environmental change. Additionally, MASTREE+ will enable investigation of the ecology and evolution of reproductive strategies in perennial plants, and the role of plant reproduction as a driver of ecosystem dynamics

The importance of anthropogenic effects in habitat use and territory size of Northern Anteater-chats Myrmecocichla aethiops near Amurum Forest Reserve, Jos-Plateau, Nigeria

Occurrence of animals in an area and the size of territories they occupy is a function of resource availability and the environmental conditions in that area. Territory location in birds is often determined by availability of nesting habitat and we investigate whether this is the case for the little-studied Northern Anteater-chat Myrmecocichla aethiops. Territory size and location were mapped over two months in 2012 at 25 different sites where the birds occurred in central Nigeria and compared to 25 random sites where they did not, 500 m away. Vegetation variables, invertebrate abundance indicators, anthropogenic variables (availability of nest sites) and bird community components were measured and compared with adjoining areas (500 m away) from which the birds were absent in order to determine important factors determining territory location and size. Territories were 1.23 ha (SE 0.14) in size and were widely separated and so non-contiguous. Increasing numbers of abandoned wells, ant nests and termite mounds increased the probability of territory occupation. Territory size increased with the number of anteater-chats but decreased with increasing number of ant nests and overall bird diversity that were probably proxies for habitat quality. Overall, choice of preferred areas for the Northern Anteater-chat was centred on nesting sites and then habitat quality and group size probably determined territory size.PostprintPeer reviewe

Aspects of the behaviour of African giant pouched rats (Cricetomys sp. nov) which impacts seed dispersal of large-seeded tree species in a West African montane forest landscape.

The loss of megafaunal vertebrate dispersers in tropical forests is strongly associated with seed dispersal limitation of large-seeded species. In the Neotropics, large scatterhoarding rodents such as agoutis and acouchies (Dasyproctidae) have been shown to be substitute dispersers of large-seeded species. In Afrotropical forests, the African giant pouched rat (Cricetomys spp) has the potential to disperse large-seeded species through scatterhoarding behaviour, but little was known about its behaviour in the forest. In this study, I investigated the behaviour of Cricetomys sp. nov in a Nigerian montane forest—Ngel Nyaki Forest Reserve (NNFR). NNFR comprises of Continous forests, forest fragments and grasslands. The main objectives of my study were to determine: i) the distribution of Cricetomys in relation to habitat ii) the distribution Cricetomys in relation to large-seeded species iii) the perception of Cricetomys’ predation risk in different microhabitats and iv) the foraging behaviour of Cricetomys in relation to seed traits, fruit abundance and seasonal aridity. Using both live and camera trapping methods, I found that Cricetomys is mostly restricted to the forest core, less abundant in the forest edges and forest fragments, and almost totally absent from grasslands of NNFR. Within the forest core, I found that the density of Cricetomys varied markedly among patches. Although there was no relationship between the actual density of Cricetomys and large-seeded tree species, I found a significant positive correlation between the density of Cricetomys burrows and the abundance of large-seeded species. In contrast to many predation risk studies of small mammals, a combination of ‘giving up density’ (GUD) and a spool-and-line methods used in the forest revealed that Cricetomys did not perceive microhabitats with dense understories as safer sites. Using the classic thread-tagging technique for seed removal experiments, I found that seed nutrient content (especially fat) rather than seed size has a significant effect on seed fate. Seeds with higher fat content were more prone to predation while seeds with higher fibre content had a slightly higher probability of being dispersed. The use of artificial seeds across the wet and dry seasons revealed that fruit abundance rather than seasonal aridity had a significant effect on the fate of seeds removed by Cricetomys in NNFR because the frequency of seed removal was only altered by the availability of background seeds. The findings from this study suggest that seed recruitment patterns of large-seeded species may vary in different patches of montane forests. They also suggest that an increase in the population of Cricetomys may have negative impacts on nutrient-rich large-seeded speeded species, while nutrient-poor large-seeded species may potentially have higher chances of being dispersed by Cricetomys. Overall, this study has shown that Cricetomys may have a significant effect in seed-recruitment patterns of tropical montane forests

Low fruit-crop years of Carapa oreophila drive increased seed removal and predation by scatterhoarding rodents in a West African forest

International audienc

Size doesn't matter: Larger Carapa seeds are not dispersed farther by African rodent community

International audienc

Landscape structure mediates zoochorous-dispersed seed rain under isolated pasture trees across distinct tropical regions

Context: Isolated pasture trees play an important role in forest recovery within fragmented tropical landscapes by attracting seed dispersers and facilitating seedling growth. However, studies with conflicting results have led to confusion about what drives variation in zoochorous-dispersed seed rain patterns under isolated tree canopies. Objectives: To assess the role of landscape and biological factors impacting zoochorous-dispersed seed rain under isolated pasture trees across three tropical regions of the world. Methods: We measured seed dispersal under 144 isolated pasture trees found in 12 fragmented tropical and sub-tropical landscapes in Australia, Colombia and Nigeria. Using linear mixed effect models, we modeled seed diversity, abundance, richness and evenness as functions of the biological features and landscape context of isolated trees. Results: Throughout all regions, the amount of woody vegetation surrounding trees in pastures was negatively related to rainforest seed diversity, evenness and abundance. Seed diversity and evenness increased significantly with the distance of isolated trees to forest fragments in the Australian sub-tropics, but elsewhere, seed diversity and evenness tended to decline with distance to forest, though not significantly. Conclusions: Our results suggest that the tree composition of landscapes surrounding isolated pasture trees is important for influencing zoochorous-dispersed seed rain, regardless of the region studied. Our study highlights the prominent role of landscape-scale, rather than local-scale factors on seed dispersal to isolated pasture trees, while providing strong evidence that early stage successional processes involving isolated pasture trees are similar throughout global tropical regions