4d: Species traits

4d:     Species traits

Conveners:     Dr. Emilia Hannula (Leiden University)

                       Dr. Fons van der Plas (Wageningen University)

                       Dr. Arnaud Louchart (Netherlands Institute of Ecology)

1. Rooting for function: Community-level fine-root traits relate to many ecosystem functions

Kathryn Barry, Utrecht University

Humans are driving unprecedented biodiversity change which will likely affect how ecosystems function. These biodiversity changes will alter the functional traits of the community and thereby potentially how ecosystems function. We test mechanistic hypotheses for how fine root traits related to resource use (specific root length, root diameter, root tissue density, and root nitrogen) and nine belowground ecosystem functions as well as aboveground biomass in a dataset of 777 plant communities across systems. We found that the community-based trait coordination did not fully match the species root economics space: we found strong evidence for a collaboration gradient but no conservation gradient. Yet, links between community-level root traits and ecosystem functioning are more common than we expected from the literature. These findings suggest that when biodiversity loss is characterized by changes in the relative abundance of species and their root traits, this may have consequences for many ecosystem functions belowground.

2. Host species traits shaping feather and preen gland bacteriomes and their functional properties

I. Maureen Baars, Veronika Gvoždíková Javůrková, Maurine W. Dietz, Joana Falcao Salles, B. Irene Tieleman, University of Groningen

Bacteria found in the preen gland and on feathers of birds are hypothesized to synthesize volatile organic compounds (VOCs), contributing to bird olfactory communication and antimicrobial defence against keratinolytic bacteria. Given these functional roles, we expected that preen gland bacteriomes are shaped by their host ecological factors, including high habitat humidities and different social systems. We aimed to determine the composition of feather and preen gland bacteriomes, and preen oil VOC profiles, in relation to host phylogeny and differences in sociality and habitat humidity. Therefore, we sampled feathers and preen oil from 530 individuals of 40 temperate bird species varying in degrees of sociality and habitat humidity conditions. We found that preen oil bacteriome, preen oil VOC and feather bacteriome diversity and composition vary significantly among bird species. We also found that the host species traits sociality and habitat humidity do not affect preen oil bacteriome and VOC diversity.

3. Trait-based approaches to understand biodiversity change in Carabid beetle communities along land use gradients.

Lianne C. Woudstra, Matty P. Berg, Jacintha Ellers, Vrije Universiteit Amsterdam

Land use gradients present an opportunity to investigate how anthropogenic pressures reshape biodiversity. This study explores carabid beetle communities along ditch borders in lowland peat meadows, with varying land use intensities. We use both classical biodiversity metrics—such as total abundance and species richness—and   functional traits to examine mechanisms underlying biodiversity change and community shifts. Land use was not correlated with species richness or total abundance, however, community composition shifted significantly, with community-weighted means of body size, habitat specialization and flight capability responding to land use intensity.  By comparing these metrics, we assess their relative value in capturing biodiversity responses to land use. Our findings demonstrate that traits can provide mechanistic insights into community dynamics that are often obscured by traditional metrics alone. The study highlights the promise and limitations of various biodiversity metrics, offering guidance on effectively monitoring biodiversity shifts in response to land use changes..

4. What’s on the menu? Interactions between deer herbivory, forage apparency and nutritional traits in a human-dominated tiger landscape.

Sciumbata Matteo, Palimar Rao Sakshi, Chaudhary Ram Raj, Aerts Rien, Cornelissen Hans, Vrije Universiteit Amsterdam

Following conservation efforts, tiger populations have increased in some human-dominated landscapes, heightening human-wildlife conflicts as tigers target domestic animals and humans when natural prey is scarce. Forage availability and quality restrain prey numbers, yet how these constraints interact with herbivory is unclear. We study these interactions by assessing deer herbivory, plant cover and nutritional traits in lowland forests and grasslands of Nepal. We show that, whereas deer prefer some highly nutritious plants, these are sparse and thus less targetable. Grasses, though readily accessible—especially in grasslands—show low nutritional value; conversely, forbs and saplings—predominant in forests—are generally less available but more nutritious plants. Thus, contrasting current beliefs, deer display a diverse diet comprising plants differing in apparency and nutritional traits. These results provide insights for vegetation management policies in South Asia, highlighting that, besides grasslands, forests play a crucial role in the diet of deer, which are vital prey for tigers. 

5. Synthesis of animal trait data across the tree of life with sharetrait: problems, pitfalls and possibilities

Wilco Verkerk, Matty Berg, Iris van de Pol, Jacintha Ellers, Vrije Universiteit Amsterdam

Here we present ShareTrait, a user-friendly platform that makes animal trait data not only Findable and Accessible, but also Interoperable and Reusable, thus embracing FAIR principles. To date, the ShareTrait database holds over 30,000 records on three traits universal to animal life: metabolic rate, development time and fecundity. A key feature is the wealth of metadata that is included in a standardized manner, which we demonstrate greatly enhances data interoperability and reusability. For instance, after accounting for differences in common covariates such as size and temperature, intraspecific trait variation was similar to variation in traits across species for both fecundity and metabolic rate, while variation in development rates was ~3 fold smaller within species, compared to across species. This makes ShareTrait a valuable resource for researchers collaborating in large-scale syntheses projects, which are urgently needed to address the complex, global environmental challenges of our time.