Spotlight on the SLOO

Another very good paper from our group today in Global Ecology and Biogeography on how to deal with spatially autocorrelated variables.

Check the paper here:

http://onlinelibrary.wiley.com/doi/10.1111/geb.12161/full

Congrats Kevin! 

New paper in Proceding Royal Society B

A new paper from our group is making the cover of Proceedings of the Royal Society B this month.

Congrats to Florian!

Barnier F., Valeix M., Duncan P., Chamaillé-Jammes S., Barre P., Loveridge A.J., Macdonald D. W., Fritz H. (in press). Diet quality in a wild grazer declines under the threat of an ambush predator. Proc.Roy.Soc.B 281: 20140446. http://dx.doi.org/10.1098/rspb.2014.0446 

Cover image:A herd of Plains zebras grazing early in the morning during the wet season in Hwange National Park, Zimbabwe. See the paper “Diet quality in a wild grazer declines under the threat of an ambush predator” by Barnier et al.published in Proceedings of the Royal Society B(http://dx.doi.org/10.1098/rspb.2014.0446). Photo Credit: Florian Barnier.

 

Here is the abstract

Predators influence prey populations not only through predation itself, but also indirectly through prompting changes in prey behaviour. The behavioural adjustments of prey to predation risk may carry nutritional costs, but this has seldom been studied in the wild in large mammals. Here, we studied the effects of an ambush predator, the African lion (Panthera leo), on the diet quality of plains zebras (Equus quagga) in Hwange National Park, Zimbabwe. We combined information on movements of both prey and predators, using GPS data, and measurements of faecal crude protein, an index of diet quality in the prey. Zebras which had been in close proximity to lions had a lower quality diet, showing that adjustments in behaviour when lions are within short distance carry nutritional costs. The ultimate fitness cost will depend on the frequency of predator–prey encounters and on whether bottom-up or top-down forces are more important in the prey population. Our finding is the first attempt to our knowledge to assess nutritionally mediated risk effects in a large mammalian prey species under the threat of an ambush predator, and brings support to the hypothesis that the behavioural effects of predation induce important risk effects on prey populations.

Séminaire Carine Prêcheur

Carine Prêcheur, Vendredi 8 novembre 2013

Titre: Processus démographiques influant sur une colonie de petite taille d’un oiseau marin tropical :colonie de puffins d’Audubon en Martinique.  

Dans un contexte de changement climatique, il devient nécessaire d’établir des modèles de prévision afin d’évaluer l’effet du climat et des facteurs météorologiques sur la démographie et le comportement des populations naturelles ainsi que ses conséquences sur l’équilibre des écosystèmes.  Dans des problématiques de gestion et de conservation, ces modèles nous permettraient d’évaluer le risque potentiel d’extinction et analyser les facteurs qui pourraient réduire ce risque.

De par leur position dans la chaine trophique, les prédateurs marins supérieurs peuvent constituer de bons indicateurs des variations climatiques.

Ici, nous nous intéresserons aux processus démographiques d’une colonie de petite taille d’un oiseau marin tropical. 

Summer Friday Talk

Hi All,

Luca is gone for greener grass:

where he will have a lots of new things to do:

For us Friday seminar will continue this summer with three different sessions:

Friday August 2nd

11.30 am Aurélie Dupeyron:

Community structure of carabid beetles in agricultural landscape

Friday August 9th

11.00 am Laura Henckel & Hélène Deraison

 INTECOL seminar

Friday September 13th

Ronan Marrec
European Carabidologist Meeting Seminar




have a good one,

Nico

AgriPop Friday Talks

Friday's Agripop Talk

28 June 2013 - 11:30 - 12:30 Salle Ragondin
2 Master student project presentations

1. Bees and their landscape: 
Mapping the distribution of floral resources in agricultural landscapes and their use by wild bees

Lindy Mary Corredores Hurtado

Centre d’Etudes Biologiques de Chizé & Universidad Javeriana (Colombia)

 &

2. Rôle des adventices dans l’écologie de l’abeille domestique en plaine agricole

Yoanna Marescot

Centre d’Etudes Biologiques de Chizé

 You know, on average one in every three bites of food eaten by humans worldwide depends on bees and other pollinators for a succesful harvest (see here) and our markets and grocery stores would look quite empty without their services:

Source: http://io9.com/if-bees-go-extinct-this-is-what-your-supermarket-will-513604512

and see also this very interesting post on the story of hand pollination in China by Bug_Girl, a researcher in entomology and famous blogger about insects.

Bus so, why are bees declining worldwide? This is actually a tricky question, as there appear to be multiple causes at work (e.g. see here and here) and multiple stressors may be at work, such as parasites or pesticides. In intensive agricultural landscapes, however, one important problem appears also to be the supply of sufficient floral resources over the season. For example, where should bees go to once these massive blooms of rapeseed fields have disappeared after only few weeks and it will take several more weeks before the sunflowers start to open up? 

This is the problem tackeld by the projects of today's speakers, Lindy and Yoanna. 

Lindy will present us her results of an intensive mapping effort wild flower resources in our study area and the use of these resources by domestic bees. Yoanna has investigated the feeding ecology of the domestic bee in our study area, investigating how the bees can manage to cover the period without massive supply of flowers from the crops (rapeseed and sunflower). 

As this will be the first time you see Yoanna's project, here a short abstract, too:

Depuis la modernisation de l’agriculture, les paysages agricoles sont modifiés, s’appauvrissent en diversité écologique alors même qu’ils ont longtemps abrité une grande richesse spécifique, notamment au niveau de la flore herbacée des champs cultivés. Il s’agit plus précisément des adventices, qui voient, comme tant d’autres groupes végétaux ses populations régressées. Pourtant les adventices joueraient un rôle important comme apport alimentaire aux pollinisateurs et plus particulièrement à l’abeille domestique. Nous étudions ici le rôle des adventices  au sein d’une plaine agricole de Poitou-Charentes, caractérisée par deux périodes où les ressources pour l’abeille se trouvent en excès, floraison du colza puis celle du tournesol, et entre les deux: une période d’insuffisance alimentaire.

So, please come, listen, and discuss!

Agripop Friday talks

Friday's Agripop Talk

14 June 2013 - 11:00 - 12:00 Salle Seminaire

Relations plantes-criquets en milieu agricole: 
étude du lien entre l’abondance des criquets et les traits fonctionnels des plantes

Gaëtane Le Provost

Centre d’Etudes Biologiques de Chizé & Université Paris Sud XI

 

Photo by Richard Seaman. Downloaded from http://richard-seaman.com/Arthropods/Russia/

Exciting times - Gaetanne, our master student (M2) has submitted her thesis this week! But now the viva is looming -- it'll be next Monday! You better get prepared ... hence Gaetanne will do a mock talk tomorrow to receive feedback. Please all of you, do come along!

 Here a summary of her thesis:

Agricultural intensification has caused a dramatic loss of perennial lands, which has resulted in strong declines of plant diversity and invertebrate populations, leading to cascade effects at many trophic levels. Understanding the mechanisms involved in the structuring of communities is crucial to understand ecosystem responses to global change. 

In this context, applying the “Holy Grail” hypothesis and the “Response-effect” framework to the study of multitrophic systems will improve our ability to understand the underlying processes implicated in the relationship between functional diversity and ecosystem functioning. By studying the link between plants and grasshoppers in agroecosystems, we want to quantify the relative effects of land use on the functional composition of grasslands and on invertebrate herbivore communities. 

Through analyses of several plant traits and their impact on grasshopper abundance, we have identified the effect of different land use components and plant functional diversity on the relationship between plants and herbivores in grasslands. This work proposes that response traits of plants to land use change the abundance of different grasshopper species. Our results confirm the existence of a functional structure in plant communities in response to land use, affecting grasshopper communities.

 Ah, no, not THIS quest for the holy grail ...:

It refers to a work by Sandra Lavorel and collegues (e.g. see here) ...

Hence, please come all - if you ask nicely you might even get some precious tips about secret spots to do nice "sorties naturalistes" in the surrounding areas ... ;-)