Our analyses

Simple faunistic inventories

From a sampling of the entomofauna in the field by a set of methods appropriate to each study, a minimum list of arthropod species present is established. This list is enriched with information on the status of species, such as their endemicity or their ecological heritage character.
In the absence of a complete identification up to the species, a morphotype is assigned to each specimen. This method makes it possible to obtain within a reasonable time a representative inventory of the bioviversity actually present and to use all the faunistic information available to produce an ecological diagnosis.

Qualitative ecological indicators

In oceanic islands, the proportion of endemic species is positively correlated with altitude and the level of habitat preservation. The proportions of native species linked to preserved habitats are also, in Réunion, good indicators of the degree of conservation of native habitats. The presence of anthropogenic species is, on the other hand, an indicator of disturbance or transformation of the habitat, even at a small scale.
These proportions are not simple percentages but are calculated with their confidence interval and can thus be broken down by site, by station or by sampled plant species.

Relationships and specificities between arthropods, plants, sites and habitats

Particular attention is paid to the relationships between arthropod species and the plants on which they are sampled. The plants which home a greater number of arthropod species specifically associated with them are thus identified as having a major ecological role for the arthropofauna; these relationships are often linked to the native status of the species at stake.
The same qualitative approach can be applied by site and by habitat.

Descriptors of arthropod communities

When the sample is standardized, the descriptors of arthropod communities, namely abundance (number of individuals), richness (number of species) and diversity (relative share of the different species in the richness) are excellent variables for measuring the effects of environmental factors (see next point).
It is also necessary to take into account the combination of these three variables: thus (example opposite), the increase in the abundance and richness of arthropods with the degradation of habitats may be accompanied by a collapse in diversity which reflects the proliferation of certain species while others are becoming scarce.

Effects of environmental factors, search for indicator species

Correlations between arthropod species and plants (or stations), or arthropods and environmental factors, can be highlighted by multivariate statistics (opposite).
When sampling is standardized, these correlations can be quantified and the effects of environmental factors (altitude, time since disturbance, etc.) on community descriptors (abundance, richness and diversity) can be quantified by hypothesis tests.

Population counts and dynamics

Sometimes it is necessary to measure the population density of certain particular species of arthropods, in time (population dynamics) or in space. Rapid visual counting methods can be developed on a case-by-case basis to assess the densities of populations present.
Population dynamics are then described and analyzed in relation to a set of potentially explanatory environmental parameters chosen a priori (climatic parameters, treatments, cultivation practices, habitat, ...).

Miscellaneous data analysis

Beyond ecological inventories and assessments, we can carry out "à la carte" a wide range of statistical analysis of experimental and environmental data, and advise on protocols prior to experimentation and data collection: population monitoring, adapted counting methods, effects of environmental practices, survival analysis ...